1
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Mishra V, Adlakha N. Numerical simulation of calcium dynamics dependent ATP degradation, IP 3 and NADH production due to obesity in a hepatocyte cell. J Biol Phys 2023; 49:415-442. [PMID: 37410245 PMCID: PMC10651622 DOI: 10.1007/s10867-023-09639-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Accepted: 06/03/2023] [Indexed: 07/07/2023] Open
Abstract
Calcium (Ca[Formula: see text]) signals have a crucial role in regulating various processes of almost every cell to maintain its structure and function. Calcium dynamics has been studied in various cells including hepatocytes by many researchers, but the mechanisms of calcium signals involved in regulation and dysregulation of various processes like ATP degradation rate, IP[Formula: see text] and NADH production rate respectively in normal and obese cells are still poorly understood. In this paper, a reaction diffusion equation of calcium is employed to propose a model of calcium dynamics by coupling ATP degradation rate, IP[Formula: see text] and NADH production rate in hepatocyte cells under normal and obese conditions. The processes like source influx, buffer, endoplasmic reticulum (ER), mitochondrial calcium uniporters (MCU) and Na[Formula: see text]/Ca[Formula: see text] exchanger (NCX) have been incorporated in the model. Linear finite element method is used along spatial dimension, and Crank-Nicolson method is used along temporal dimension for numerical simulation. The results have been obtained for the normal hepatocyte cells and for cells due to obesity. The comparative study of these results reveal significant difference caused due to obesity in Ca[Formula: see text] dynamics as well as in ATP degradation rate, IP[Formula: see text] and NADH production rate.
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Affiliation(s)
- Vedika Mishra
- Department of Mathematics, SVNIT, Surat, 395007, Gujarat, India.
| | - Neeru Adlakha
- Department of Mathematics, SVNIT, Surat, 395007, Gujarat, India
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2
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Tassone A, Meringolo M, Ponterio G, Bonsi P, Schirinzi T, Martella G. Mitochondrial Bioenergy in Neurodegenerative Disease: Huntington and Parkinson. Int J Mol Sci 2023; 24:ijms24087221. [PMID: 37108382 PMCID: PMC10138549 DOI: 10.3390/ijms24087221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 04/10/2023] [Accepted: 04/11/2023] [Indexed: 04/29/2023] Open
Abstract
Strong evidence suggests a correlation between degeneration and mitochondrial deficiency. Typical cases of degeneration can be observed in physiological phenomena (i.e., ageing) as well as in neurological neurodegenerative diseases and cancer. All these pathologies have the dyshomeostasis of mitochondrial bioenergy as a common denominator. Neurodegenerative diseases show bioenergetic imbalances in their pathogenesis or progression. Huntington's chorea and Parkinson's disease are both neurodegenerative diseases, but while Huntington's disease is genetic and progressive with early manifestation and severe penetrance, Parkinson's disease is a pathology with multifactorial aspects. Indeed, there are different types of Parkinson/Parkinsonism. Many forms are early-onset diseases linked to gene mutations, while others could be idiopathic, appear in young adults, or be post-injury senescence conditions. Although Huntington's is defined as a hyperkinetic disorder, Parkinson's is a hypokinetic disorder. However, they both share a lot of similarities, such as neuronal excitability, the loss of striatal function, psychiatric comorbidity, etc. In this review, we will describe the start and development of both diseases in relation to mitochondrial dysfunction. These dysfunctions act on energy metabolism and reduce the vitality of neurons in many different brain areas.
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Affiliation(s)
- Annalisa Tassone
- Laboratory of Neurophysiology and Plasticity, IRCCS Fondazione Santa Lucia, 00143 Rome, Italy
| | - Maria Meringolo
- Laboratory of Neurophysiology and Plasticity, IRCCS Fondazione Santa Lucia, 00143 Rome, Italy
- Saint Camillus International University of Health and Medical Sciences, 00131 Rome, Italy
| | - Giulia Ponterio
- Laboratory of Neurophysiology and Plasticity, IRCCS Fondazione Santa Lucia, 00143 Rome, Italy
| | - Paola Bonsi
- Laboratory of Neurophysiology and Plasticity, IRCCS Fondazione Santa Lucia, 00143 Rome, Italy
| | - Tommaso Schirinzi
- Unit of Neurology, Department of Systems Medicine, Tor Vergata University of Rome, 00133 Rome, Italy
| | - Giuseppina Martella
- Laboratory of Neurophysiology and Plasticity, IRCCS Fondazione Santa Lucia, 00143 Rome, Italy
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3
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Voglhuber J, Holzer M, Radulović S, Thai PN, Djalinac N, Matzer I, Wallner M, Bugger H, Zirlik A, Leitinger G, Dedkova EN, Bers DM, Ljubojevic-Holzer S. Functional remodelling of perinuclear mitochondria alters nucleoplasmic Ca 2+ signalling in heart failure. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210320. [PMID: 36189813 PMCID: PMC9527904 DOI: 10.1098/rstb.2021.0320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 01/23/2022] [Indexed: 11/12/2022] Open
Abstract
Mitochondrial dysfunction in cardiomyocytes is a hallmark of heart failure development. Although initial studies recognized the importance of different mitochondrial subpopulations, there is a striking lack of direct comparison of intrafibrillar (IF) versus perinuclear (PN) mitochondria during the development of HF. Here, we use multiple approaches to examine the morphology and functional properties of IF versus PN mitochondria in pressure overload-induced cardiac remodelling in mice, and in non-failing and failing human cardiomyocytes. We demonstrate that PN mitochondria from failing cardiomyocytes are more susceptible to depolarization of mitochondrial membrane potential, reactive oxygen species generation and impairment in Ca2+ uptake compared with IF mitochondria at baseline and under physiological stress protocol. We also demonstrate, for the first time to our knowledge, that under normal conditions PN mitochondrial Ca2+ uptake shapes nucleoplasmic Ca2+ transients (CaTs) and limits nucleoplasmic Ca2+ loading. The loss of PN mitochondrial Ca2+ buffering capacity translates into increased nucleoplasmic CaTs and may explain disproportionate rise in nucleoplasmic [Ca2+] in failing cardiomyocytes at increased stimulation frequencies. Therefore, a previously unidentified benefit of restoring the mitochondrial Ca2+ uptake may be normalization of nuclear Ca2+ signalling and alleviation of altered excitation-transcription, which could be an important therapeutic approach to prevent adverse cardiac remodelling. This article is part of the theme issue 'The cardiomyocyte: new revelations on the interplay between architecture and function in growth, health, and disease'.
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Affiliation(s)
- Julia Voglhuber
- Department of Cardiology, Medical University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
| | - Michael Holzer
- BioTechMed-Graz, Graz, Austria
- Division of Pharmacology, Otto-Loewi Research Centre, Medical University of Graz, Graz, Austria
| | - Snježana Radulović
- Research Unit Electron Microscopic Techniques, Division of Cell Biology, Histology and Embryology, Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | - Phung N. Thai
- Department of Internal Medicine, Cardiovascular Medicine, University of California Davis, Davis, CA, USA
| | - Natasa Djalinac
- Department of Cardiology, Medical University of Graz, Graz, Austria
| | - Ingrid Matzer
- Department of Cardiology, Medical University of Graz, Graz, Austria
| | - Markus Wallner
- Department of Cardiology, Medical University of Graz, Graz, Austria
- Lewis Katz School of Medicine, Temple University, Cardiovascular Research Center, Philadelphia, PA, USA
| | - Heiko Bugger
- Department of Cardiology, Medical University of Graz, Graz, Austria
| | - Andreas Zirlik
- Department of Cardiology, Medical University of Graz, Graz, Austria
| | - Gerd Leitinger
- Research Unit Electron Microscopic Techniques, Division of Cell Biology, Histology and Embryology, Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | - Elena N. Dedkova
- Department of Pharmacology, University of California Davis, Davis, CA, USA
- Department of Molecular Biosciences, University of California Davis, Davis, CA, USA
| | - Donald M. Bers
- Department of Pharmacology, University of California Davis, Davis, CA, USA
| | - Senka Ljubojevic-Holzer
- Department of Cardiology, Medical University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
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4
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Darbandi S, Darbandi M, Khorram Khorshid HR, Sengupta P. Electrophysiology of Human Gametes: A Systematic Review. World J Mens Health 2022; 40:442-455. [PMID: 35021309 PMCID: PMC9253800 DOI: 10.5534/wjmh.210107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 09/05/2021] [Accepted: 09/14/2021] [Indexed: 11/15/2022] Open
Abstract
PURPOSE Oocytes and spermatozoa are electrogenic cells with the ability to respond to electrical stimuli and modulate their electrical properties accordingly. Determination of the ionic events during the gamete maturation helps to design suitable culture media for gametes in assisted reproductive technology (ART). The present systematic review focuses on the electrophysiology of human gametes during different stages of maturation and also during fertilization. MATERIALS AND METHODS The reports published in the English language between January 2000 and July 2021 were extracted from various electronic scientific databases following the PRISMA checklist using specific MeSH keywords. RESULTS Subsequent to the screening process with defined inclusion and exclusion criteria, 60 articles have been included in this review. Among them, 11 articles were directly related to the electrophysiology of human oocytes and 49 physiology department to the electrophysiology of human spermatozoa. CONCLUSIONS Gametes generate electrical currents by ionic exchange, particularly Na+, K+, Cl-, H+, Zn2+, Cu2+, Se2+, Mg2+, HCO3-, and Ca2+ through specific ion channels in different stages of gamete maturation. The ionic concentrations, pH, and other physicochemical variables are modulated during the gametogenesis, maturation, activation, and the fertilization process following gamete function and metabolism. The electrical properties of human gametes change during different stages of maturation. Although it is demonstrated that the electrical properties are significant regulators of cell signaling and are fundamental to gamete maturation and fertilization, their exact roles in these processes are still poorly understood. Further research is required to unveil the intricate electrophysiological processes of human gamete maturation.
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Affiliation(s)
- Sara Darbandi
- Fetal Health Research Center, Hope Generation Foundation, Tehran, Iran
| | - Mahsa Darbandi
- Fetal Health Research Center, Hope Generation Foundation, Tehran, Iran
| | - Hamid Reza Khorram Khorshid
- Gene Therapy and Regenerative Medicine Research Center, Hope Generation Foundation, Tehran, Iran
- Personalized Medicine and Genometabolomics Research Center, Hope Generation Foundation, Tehran, Iran
| | - Pallav Sengupta
- Department of Physiology, Faculty of Medicine, Biosciences and Nursing, MAHSA University, Jenjarom, Selangor, Malaysia
- School of Medical Sciences, Bharath Institute of Higher Education and Research (BIHER), Chennai, India.
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Verma M, Lizama BN, Chu CT. Excitotoxicity, calcium and mitochondria: a triad in synaptic neurodegeneration. Transl Neurodegener 2022; 11:3. [PMID: 35078537 PMCID: PMC8788129 DOI: 10.1186/s40035-021-00278-7] [Citation(s) in RCA: 125] [Impact Index Per Article: 62.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 12/29/2021] [Indexed: 02/08/2023] Open
Abstract
Glutamate is the most commonly engaged neurotransmitter in the mammalian central nervous system, acting to mediate excitatory neurotransmission. However, high levels of glutamatergic input elicit excitotoxicity, contributing to neuronal cell death following acute brain injuries such as stroke and trauma. While excitotoxic cell death has also been implicated in some neurodegenerative disease models, the role of acute apoptotic cell death remains controversial in the setting of chronic neurodegeneration. Nevertheless, it is clear that excitatory synaptic dysregulation contributes to neurodegeneration, as evidenced by protective effects of partial N-methyl-D-aspartate receptor antagonists. Here, we review evidence for sublethal excitatory injuries in relation to neurodegeneration associated with Parkinson's disease, Alzheimer's disease, amyotrophic lateral sclerosis and Huntington's disease. In contrast to classic excitotoxicity, emerging evidence implicates dysregulation of mitochondrial calcium handling in excitatory post-synaptic neurodegeneration. We discuss mechanisms that regulate mitochondrial calcium uptake and release, the impact of LRRK2, PINK1, Parkin, beta-amyloid and glucocerebrosidase on mitochondrial calcium transporters, and the role of autophagic mitochondrial loss in axodendritic shrinkage. Finally, we discuss strategies for normalizing the flux of calcium into and out of the mitochondrial matrix, thereby preventing mitochondrial calcium toxicity and excitotoxic dendritic loss. While the mechanisms that underlie increased uptake or decreased release of mitochondrial calcium vary in different model systems, a common set of strategies to normalize mitochondrial calcium flux can prevent excitatory mitochondrial toxicity and may be neuroprotective in multiple disease contexts.
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Affiliation(s)
- Manish Verma
- grid.21925.3d0000 0004 1936 9000Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261 USA ,grid.423286.90000 0004 0507 1326Present Address: Astellas Pharma Inc., 9 Technology Drive, Westborough, MA 01581 USA
| | - Britney N. Lizama
- grid.21925.3d0000 0004 1936 9000Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261 USA
| | - Charleen T. Chu
- grid.21925.3d0000 0004 1936 9000Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261 USA ,grid.21925.3d0000 0004 1936 9000Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261 USA ,grid.21925.3d0000 0004 1936 9000Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261 USA ,grid.21925.3d0000 0004 1936 9000McGowan Institute for Regenerative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261 USA ,grid.21925.3d0000 0004 1936 9000Center for Protein Conformational Diseases, University of Pittsburgh, Pittsburgh, PA 15261 USA ,grid.21925.3d0000 0004 1936 9000Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA 15261 USA
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6
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A non-canonical role for pyruvate kinase M2 as a functional modulator of Ca 2+ signalling through IP 3 receptors. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2022; 1869:119206. [PMID: 35026348 DOI: 10.1016/j.bbamcr.2021.119206] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 12/20/2021] [Accepted: 12/23/2021] [Indexed: 12/22/2022]
Abstract
Pyruvate kinase isoform M2 (PKM2) is a rate-limiting glycolytic enzyme that is widely expressed in embryonic tissues. The expression of PKM2 declines in some tissues following embryogenesis, while other pyruvate kinase isozymes are upregulated. However, PKM2 is highly expressed in cancer cells and is believed to play a role in supporting anabolic processes during tumour formation. In this study, PKM2 was identified as an inositol 1,4,5-trisphosphate receptor (IP3R)-interacting protein by mass spectrometry. The PKM2:IP3R interaction was further characterized by pull-down and co-immunoprecipitation assays, which showed that PKM2 interacted with all three IP3R isoforms. Moreover, fluorescence microscopy indicated that both IP3R and PKM2 localized at the endoplasmic reticulum. PKM2 binds to IP3R at a highly conserved 21-amino acid site (corresponding to amino acids 2078-2098 in mouse type 1 IP3R isoform). Synthetic peptides (denoted 'TAT-D5SD' and 'D5SD'), based on the amino acid sequence at this site, disrupted the PKM2:IP3R interaction and potentiated IP3R-mediated Ca2+ release both in intact cells (TAT-D5SD peptide) and in a unidirectional 45Ca2+ flux assay on permeabilized cells (D5SD peptide). The TAT-D5SD peptide did not affect the enzymatic activity of PKM2. Reducing PKM2 protein expression using siRNA increased IP3R-mediated Ca2+ signalling in intact cells without altering the ER Ca2+ content. These data identify PKM2 as an IP3R-interacting protein that inhibits intracellular Ca2+ signalling. The elevated expression of PKM2 in cancer cells is therefore not solely connected to its canonical role in glycolytic metabolism, rather PKM2 also has a novel non-canonical role in regulating intracellular signalling.
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7
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Yıldızhan K, Nazıroğlu M. Protective role of selenium on MPP + and homocysteine-induced TRPM2 channel activation in SH-SY5Y cells. J Recept Signal Transduct Res 2021; 42:399-408. [PMID: 34583611 DOI: 10.1080/10799893.2021.1981381] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Homocysteine is an intermediate product of biochemical reactions occurring in living organisms. It is known that drugs that increase dopamine synthesis used in Parkinson's disease (PD) cause an increase in the plasma homocysteine level. As the plasma homocysteine level increases, the amount of intracellular free calcium ion ([Ca2+]i) and oxidative stress increase. As a result, it contributes to the excitotoxic effect by causing neurodegeneration. TRPM2 cation channel is activated by high [Ca2+]i and oxidative stress. The role of TRPM2 in the development of neuronal damage due to the increase in homocysteine in PD has not yet been elucidated. In current study, we aimed to investigate the role of the TRPM2 and selenium (Se) in SH-SY5Y neuronal cells treated with homocysteine (HCT) and MPP . SH-SY5Y cells were divided into four groups: control, MPP, MPP + HCT, and MPP + HCT + Se. The results of plate reader assay, confocal microscope imaging, and western blot analyses indicated upregulation of apoptosis, [Ca2+]i, mitochondrial membrane depolarization, caspase activation, and intracellular ROS values in the cells. The MPP + HCT group had considerably higher values than the other groups. The MPP + HCT + Se group had significantly lower values than all the other groups except the control group. In addition, incubation of MPP + HCT and MPP + HCT + Se groups with TRPM2 antagonist 2-APB increased cell viability and reduced intracellular calcium influx and apoptosis levels. It is concluded that the activation of TRPM2 was propagated in HCT and MPP-induced SH-SY5Y cells by the increase of oxidative stress. The antioxidant property of Se regulated the TRPM2 channel activation and neurodegeneration by providing intracellular oxidant/antioxidant balance.
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Affiliation(s)
- Kenan Yıldızhan
- Department of Biophysics, Faculty of Medicine, Van Yuzuncu Yıl University, Van, Turkey
| | - Mustafa Nazıroğlu
- Department of Biophysics, Faculty of Medicine, Suleyman Demirel University, Isparta, Turkey.,Neuroscience Research Center (NOROBAM), Suleyman Demirel University, Isparta, Turkey.,Drug Discovery Unit, BSN Health, Analysis and Innovation Ltd. Inc., Isparta, Turkey
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8
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Ngo J, Osto C, Villalobos F, Shirihai OS. Mitochondrial Heterogeneity in Metabolic Diseases. BIOLOGY 2021; 10:biology10090927. [PMID: 34571805 PMCID: PMC8470264 DOI: 10.3390/biology10090927] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 09/03/2021] [Accepted: 09/08/2021] [Indexed: 11/16/2022]
Abstract
Simple Summary Often times mitochondria within a single cell are depicted as homogenous entities both morphologically and functionally. In normal and diseased states, mitochondria are heterogeneous and display distinct functional properties. In both cases, mitochondria exhibit differences in morphology, membrane potential, and mitochondrial calcium levels. However, the degree of heterogeneity is different during disease; or rather, heterogeneity at the physiological state stems from physically distinct mitochondrial subpopulations. Overall, mitochondrial heterogeneity is both beneficial and detrimental to the cellular system; protective in enabling cellular adaptation to biological stress or detrimental in inhibiting protective mechanisms. Abstract Mitochondria have distinct architectural features and biochemical functions consistent with cell-specific bioenergetic needs. However, as imaging and isolation techniques advance, heterogeneity amongst mitochondria has been observed to occur within the same cell. Moreover, mitochondrial heterogeneity is associated with functional differences in metabolic signaling, fuel utilization, and triglyceride synthesis. These phenotypic associations suggest that mitochondrial subpopulations and heterogeneity influence the risk of metabolic diseases. This review examines the current literature regarding mitochondrial heterogeneity in the pancreatic beta-cell and renal proximal tubules as they exist in the pathological and physiological states; specifically, pathological states of glucolipotoxicity, progression of type 2 diabetes, and kidney diseases. Emphasis will be placed on the benefits of balancing mitochondrial heterogeneity and how the disruption of balancing heterogeneity leads to impaired tissue function and disease onset.
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Affiliation(s)
- Jennifer Ngo
- Department of Medicine, Division of Endocrinology, David Geffen School of Medicine at UCLA, 650 Charles E. Young Drive East, Los Angeles, CA 90095, USA; (J.N.); (C.O.); (F.V.)
- Department of Chemistry and Biochemistry, University of California, 607 Charles E. Young Drive East, Los Angeles, CA 90095, USA
- Metabolism Theme, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Corey Osto
- Department of Medicine, Division of Endocrinology, David Geffen School of Medicine at UCLA, 650 Charles E. Young Drive East, Los Angeles, CA 90095, USA; (J.N.); (C.O.); (F.V.)
- Metabolism Theme, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, 650 Charles E. Young Drive East, Los Angeles, CA 90095, USA
| | - Frankie Villalobos
- Department of Medicine, Division of Endocrinology, David Geffen School of Medicine at UCLA, 650 Charles E. Young Drive East, Los Angeles, CA 90095, USA; (J.N.); (C.O.); (F.V.)
- Department of Integrative Biology and Physiology, University of California, Los Angeles, CA 90095, USA
| | - Orian S. Shirihai
- Department of Medicine, Division of Endocrinology, David Geffen School of Medicine at UCLA, 650 Charles E. Young Drive East, Los Angeles, CA 90095, USA; (J.N.); (C.O.); (F.V.)
- Metabolism Theme, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, 650 Charles E. Young Drive East, Los Angeles, CA 90095, USA
- Molecular Biology Institute, University of California, Los Angeles, CA 90095, USA
- Correspondence:
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9
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Vandenberg GG, Dawson NJ, Head A, Scott GR, Scott AL. Astrocyte-mediated disruption of ROS homeostasis in Fragile X mouse model. Neurochem Int 2021; 146:105036. [PMID: 33785420 DOI: 10.1016/j.neuint.2021.105036] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 03/03/2021] [Accepted: 03/22/2021] [Indexed: 12/19/2022]
Abstract
Astrocytes, glial cells within the brain, work to protect neurons during high levels of activity by maintaining oxidative homeostasis via regulation of energy supply and antioxidant systems. In recent years, mitochondrial dysfunction has been highlighted as an underlying factor of pathology in many neurological disorders. In animal studies of Fragile X Syndrome (FXS), the leading genetic cause of autism, higher levels of reactive oxygen species, lipid peroxidation, and protein oxidation within the brain indicates that mitochondria function is also altered in FXS. Despite their integral contribution to redox homeostasis within the CNS, the role of astrocytes on the occurrence or progression of neurodevelopmental disorders in this way is rarely considered. This study specifically examines changes to astrocyte mitochondrial function and antioxidant expression that may occur in FXS. Using the Fmr1 knockout (KO) mouse model, mitochondrial respiration and reactive oxygen species (ROS) emission were analyzed in primary cortical astrocytes. While mitochondrial respiration was similar between genotypes, ROS emission was significantly elevated in Fmr1 KO astrocytes. Notably, NADPH-oxidase 2 expression in Fmr1 KO astrocytes was also enhanced but only changes in catalase antioxidant enzyme expression were noted. Characterization of astrocyte factors involved in redox imbalance is invaluable to uncovering potential sources of oxidative stress in neurodevelopmental disorders and more specifically, the intercellular mechanisms that contribute to dysfunction in FXS.
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Affiliation(s)
- Gregory G Vandenberg
- Department of Pathology and Molecular Medicine, McMaster University, 1200 Main St. West, Hamilton, Ontario, L8N 3Z5, Canada
| | - Neal J Dawson
- Department of Biology, McMaster University, 1280 Main St. West, Hamilton, Ontario, L8S 4K1, Canada
| | - Alison Head
- Department of Pathology and Molecular Medicine, McMaster University, 1200 Main St. West, Hamilton, Ontario, L8N 3Z5, Canada
| | - Graham R Scott
- Department of Biology, McMaster University, 1280 Main St. West, Hamilton, Ontario, L8S 4K1, Canada
| | - Angela L Scott
- Department of Pathology and Molecular Medicine, McMaster University, 1200 Main St. West, Hamilton, Ontario, L8N 3Z5, Canada.
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10
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Nazıroğlu M, Öz A, Yıldızhan K. Selenium and Neurological Diseases: Focus on Peripheral Pain and TRP Channels. Curr Neuropharmacol 2021; 18:501-517. [PMID: 31903884 PMCID: PMC7457405 DOI: 10.2174/1570159x18666200106152631] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 11/26/2019] [Accepted: 01/04/2020] [Indexed: 12/18/2022] Open
Abstract
Pain is a complex physiological process that includes many components. Growing evidence supports the idea that oxidative stress and Ca2+ signaling pathways participate in pain detection by neurons. The main source of endogenous reactive oxygen species (ROS) is mitochondrial dysfunction induced by membrane depolarization, which is in turn caused by Ca2+ influx into the cytosol of neurons. ROS are controlled by antioxidants, including selenium. Selenium plays an important role in the nervous system, including the brain, where it acts as a cofactor for glutathione peroxidase and is incorporated into selenoproteins involved in antioxidant defenses. It has neuroprotective effects through modulation of excessive ROS production, inflammation, and Ca2+ overload in several diseases, including inflammatory pain, hypersensitivity, allodynia, diabetic neuropathic pain, and nociceptive pain. Ca2+ entry across membranes is mediated by different channels, including transient receptor potential (TRP) channels, some of which (e.g., TRPA1, TRPM2, TRPV1, and TRPV4) can be activated by oxidative stress and have a role in the induction of peripheral pain. The results of recent studies indicate the modulator roles of selenium in peripheral pain through inhibition of TRP channels in the dorsal root ganglia of experimental animals. This review summarizes the protective role of selenium in TRP channel regulation, Ca2+ signaling, apoptosis, and mitochondrial oxidative stress in peripheral pain induction.
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Affiliation(s)
- Mustafa Nazıroğlu
- Neuroscience Research Center, Suleyman Demirel University, Isparta, Turkey.,Department of Biophysics, Faculty of Medicine, Suleyman Demirel University, Isparta, Turkey.,Drug Discovery Unit, BSN Health, Analysis and Innovation Ltd. Inc. Teknokent, Isparta, Turkey
| | - Ahmi Öz
- Department of Biophysics, Faculty of Medicine, Suleyman Demirel University, Isparta, Turkey
| | - Kenan Yıldızhan
- Department of Biophysics, Faculty of Medicine, Suleyman Demirel University, Isparta, Turkey
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11
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Kim E, Lee DM, Seo MJ, Lee HJ, Choi KS. Intracellular Ca 2 + Imbalance Critically Contributes to Paraptosis. Front Cell Dev Biol 2021; 8:607844. [PMID: 33585447 PMCID: PMC7873879 DOI: 10.3389/fcell.2020.607844] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 12/07/2020] [Indexed: 01/04/2023] Open
Abstract
Paraptosis is a type of programmed cell death that is characterized by dilation of the endoplasmic reticulum (ER) and/or mitochondria. Since paraptosis is morphologically and biochemically different from apoptosis, understanding its regulatory mechanisms may provide a novel therapeutic strategy in malignant cancer cells that have proven resistant to conventional pro-apoptotic treatments. Relatively little is known about the molecular basis of paraptosis, but perturbations of cellular proteostasis and ion homeostasis appear to critically contribute to the process. Ca2+ transport has been shown to be important in the paraptosis induced by several natural products, metal complexes, and co-treatment with proteasome inhibitors and certain Ca2+-modulating agents. In particular, the Ca2+-mediated communication between the ER and mitochondria plays a crucial role in paraptosis. Mitochondrial Ca2+ overload from the intracellular Ca2+-flux system located at the ER–mitochondrial axis can induce mitochondrial dilation during paraptosis, while the accumulation of misfolded proteins within the ER lumen is believed to exert an osmotic force and draw water from the cytoplasm to distend the ER lumen. In this process, Ca2+ release from the ER also critically contributes to aggravating ER stress and ER dilation. This review focuses on the role of Ca2+ transport in paraptosis by summarizing the recent findings related to the actions of Ca2+-modulating paraptosis-inducing agents and discussing the potential cancer therapeutic strategies that may effectively induce paraptosis via Ca2+ signaling.
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Affiliation(s)
- Eunhee Kim
- Department of Biological Sciences, Ulsan National Institute Science and Technology, Ulsan, South Korea
| | - Dong Min Lee
- Department of Biochemistry, Ajou University School of Medicine, Suwon, South Korea
| | - Min Ji Seo
- Department of Biochemistry, Ajou University School of Medicine, Suwon, South Korea
| | - Hong Jae Lee
- Department of Biochemistry, Ajou University School of Medicine, Suwon, South Korea
| | - Kyeong Sook Choi
- Department of Biochemistry, Ajou University School of Medicine, Suwon, South Korea
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12
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Georgiadou E, Rutter GA. Control by Ca 2+ of mitochondrial structure and function in pancreatic β-cells. Cell Calcium 2020; 91:102282. [PMID: 32961506 PMCID: PMC7116533 DOI: 10.1016/j.ceca.2020.102282] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 08/25/2020] [Accepted: 08/25/2020] [Indexed: 12/11/2022]
Abstract
Mitochondria play a central role in glucose metabolism and the stimulation of insulin secretion from pancreatic β-cells. In this review, we discuss firstly the regulation and roles of mitochondrial Ca2+ transport in glucose-regulated insulin secretion, and the molecular machinery involved. Next, we discuss the evidence that mitochondrial dysfunction in β-cells is associated with type 2 diabetes, from a genetic, functional and structural point of view, and then the possibility that these changes may in part be mediated by dysregulation of cytosolic Ca2+. Finally, we review the importance of preserved mitochondrial structure and dynamics for mitochondrial gene expression and their possible relevance to the pathogenesis of type 2 diabetes.
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Affiliation(s)
- Eleni Georgiadou
- Section of Cell Biology and Functional Genomics, Department of Metabolism, Digestion and Reproduction, Imperial College London, du Cane Road, London, W12 0NN, UK
| | - Guy A Rutter
- Section of Cell Biology and Functional Genomics, Department of Metabolism, Digestion and Reproduction, Imperial College London, du Cane Road, London, W12 0NN, UK.
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13
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Yang L, Youngblood H, Wu C, Zhang Q. Mitochondria as a target for neuroprotection: role of methylene blue and photobiomodulation. Transl Neurodegener 2020; 9:19. [PMID: 32475349 PMCID: PMC7262767 DOI: 10.1186/s40035-020-00197-z] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 05/06/2020] [Indexed: 12/18/2022] Open
Abstract
Mitochondrial dysfunction plays a central role in the formation of neuroinflammation and oxidative stress, which are important factors contributing to the development of brain disease. Ample evidence suggests mitochondria are a promising target for neuroprotection. Recently, methods targeting mitochondria have been considered as potential approaches for treatment of brain disease through the inhibition of inflammation and oxidative injury. This review will discuss two widely studied approaches for the improvement of brain mitochondrial respiration, methylene blue (MB) and photobiomodulation (PBM). MB is a widely studied drug with potential beneficial effects in animal models of brain disease, as well as limited human studies. Similarly, PBM is a non-invasive treatment that promotes energy production and reduces both oxidative stress and inflammation, and has garnered increasing attention in recent years. MB and PBM have similar beneficial effects on mitochondrial function, oxidative damage, inflammation, and subsequent behavioral symptoms. However, the mechanisms underlying the energy enhancing, antioxidant, and anti-inflammatory effects of MB and PBM differ. This review will focus on mitochondrial dysfunction in several different brain diseases and the pathological improvements following MB and PBM treatment.
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Affiliation(s)
- Luodan Yang
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, 1120 15th Street, Augusta, GA, 30912, USA
| | - Hannah Youngblood
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, 1120 15th Street, Augusta, GA, 30912, USA
| | - Chongyun Wu
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, 1120 15th Street, Augusta, GA, 30912, USA
| | - Quanguang Zhang
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, 1120 15th Street, Augusta, GA, 30912, USA.
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14
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Dey K, Bazala MA, Kuznicki J. Targeting mitochondrial calcium pathways as a potential treatment against Parkinson's disease. Cell Calcium 2020; 89:102216. [PMID: 32473487 DOI: 10.1016/j.ceca.2020.102216] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 05/06/2020] [Accepted: 05/08/2020] [Indexed: 12/14/2022]
Abstract
Parkinson's disease (PD) is a major health problem worldwide affecting millions of people and is a result of neurodegeneration in a small part of the brain known as substantia nigra pars compacta. Aberration in mitochondrial Ca2+ homeostasis plays, among several other factors, an important role for the neuronal loss in PD. Mitochondria are vital for cellular physiology, e.g. for ATP generation, and mitochondrial Ca2+ is a key player in cell functioning and survival. Mitochondrial Ca2+ homeostasis is maintained by a fine balance between the activities of proteins mediating the influx and efflux of Ca2+ across mitochondrial membranes. Malfunctioning of these proteins leading to Ca2+ overload promotes ROS generation, which induces cell death by triggering the opening of mitochondrial permeability transition pore. Till now PD remains incurable and the "gold standard" drug which can only delays the disease progression is l-Dopa from the 1960s and therefore, the situation warrants the search for novel targets for the treatment of the PD patients. In this review, we summarize the current views that suggest mitochondrial Ca2+ regulatory pathways are good candidates for the treatment of PD.
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Affiliation(s)
- Kuntal Dey
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland.
| | - Michal A Bazala
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology, Warsaw, Poland.
| | - Jacek Kuznicki
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology, Warsaw, Poland.
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15
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Wu S, Lu Q, Ding Y, Wu Y, Qiu Y, Wang P, Mao X, Huang K, Xie Z, Zou MH. Hyperglycemia-Driven Inhibition of AMP-Activated Protein Kinase α2 Induces Diabetic Cardiomyopathy by Promoting Mitochondria-Associated Endoplasmic Reticulum Membranes In Vivo. Circulation 2020; 139:1913-1936. [PMID: 30646747 DOI: 10.1161/circulationaha.118.033552] [Citation(s) in RCA: 163] [Impact Index Per Article: 40.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Fundc1 (FUN14 domain containing 1), an outer mitochondrial membrane protein, is important for mitophagy and mitochondria-associated endoplasmic reticulum membranes (MAMs). The roles of Fundc1 and MAMs in diabetic hearts remain unknown. The aims of this study, therefore, were to determine whether the diabetes mellitus-induced Fundc1 expression could increase MAM formation, and whether disruption of MAM formation improves diabetic cardiac function. METHODS Levels of FUNDC1 were examined in the hearts from diabetic patients and nondiabetic donors. Levels of Fundc1-induced MAMs and mitochondrial and heart function were examined in mouse neonatal cardiomyocytes exposed to high glucose (HG, 30 mmol/L d-glucose for 48 hours), and in streptozotocin-treated cardiac-specific Fundc1 knockout mice and cardiac-specific Fundc1 knockout diabetic Akita mice, as well. RESULTS FUNDC1 levels were significantly elevated in cardiac tissues from diabetic patients in comparison with those from nondiabetic donors. In cultured mouse neonatal cardiomyocytes, HG conditions increased levels of Fundc1, the inositol 1,4,5-trisphosphate type 2 receptor (Ip3r2), and MAMs. Genetic downregulation of either Fundc1 or Ip3r2 inhibited MAM formation, reduced endoplasmic reticulum-mitochondrial Ca2+ flux, and improved mitochondrial function in HG-treated cardiomyocytes. Consistently, adenoviral overexpression of Fundc1 promoted MAM formation, mitochondrial Ca2+ increase, and mitochondrial dysfunction in cardiomyocytes exposed to normal glucose (5.5 mmol/L d-glucose). In comparison with nondiabetic controls, levels of Fundc1, Ip3r2, and MAMs were significantly increased in hearts from streptozotocin-treated mice and Akita mice. Furthermore, in comparison with control hearts, diabetes mellitus markedly increased coimmunoprecipitation of Fundc1 and Ip3r2. The binding of Fundc1 to Ip3r2 inhibits Ip3r2 ubiquitination and proteasome-mediated degradation. Cardiomyocyte-specific Fundc1 deletion ablated diabetes mellitus-induced MAM formation, prevented mitochondrial Ca2+ increase, mitochondrial fragmentation, and apoptosis with improved mitochondrial functional capacity and cardiac function. In mouse neonatal cardiomyocytes, HG suppressed AMP-activated protein kinase activity. Furthermore, in cardiomyocytes of Prkaa2 knockout mice, expression of Fundc1, MAM formation, and mitochondrial Ca2+ levels were significantly increased. Finally, adenoviral overexpression of a constitutively active mutant AMP-activated protein kinase ablated HG-induced MAM formation and mitochondrial dysfunction. CONCLUSIONS We conclude that diabetes mellitus suppresses AMP-activated protein kinase, initiating Fundc1-mediated MAM formation, mitochondrial dysfunction, and cardiomyopathy, suggesting that AMP-activated protein kinase-induced Fundc1 suppression is a valid target to treat diabetic cardiomyopathy.
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Affiliation(s)
- Shengnan Wu
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta (S.W., Q.L., Y.D., Y.W., Y.Q., Z.X., M.-H.Z.)
| | - Qiulun Lu
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta (S.W., Q.L., Y.D., Y.W., Y.Q., Z.X., M.-H.Z.)
| | - Ye Ding
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta (S.W., Q.L., Y.D., Y.W., Y.Q., Z.X., M.-H.Z.)
| | - Yin Wu
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta (S.W., Q.L., Y.D., Y.W., Y.Q., Z.X., M.-H.Z.)
| | - Yu Qiu
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta (S.W., Q.L., Y.D., Y.W., Y.Q., Z.X., M.-H.Z.)
| | - Pei Wang
- Mitochondria and Metabolism Center, University of Washington, Seattle (P.W.)
| | - Xiaoxiang Mao
- Wuhan Union Hospital, Huazhong University of Science and Technology, Hubei, China (Z.M., K.H.)
| | - Kai Huang
- Wuhan Union Hospital, Huazhong University of Science and Technology, Hubei, China (Z.M., K.H.)
| | - Zhonglin Xie
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta (S.W., Q.L., Y.D., Y.W., Y.Q., Z.X., M.-H.Z.)
| | - Ming-Hui Zou
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta (S.W., Q.L., Y.D., Y.W., Y.Q., Z.X., M.-H.Z.)
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High-Throughput Screening Using Photoluminescence Probe to Measure Intracellular Calcium Levels. Methods Mol Biol 2019; 1925:1-14. [PMID: 30674012 DOI: 10.1007/978-1-4939-9018-4_1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2023]
Abstract
Aequorin, a 22 kDa protein produced by the jellyfish Aequorea victoria, was the first probe used to measure Ca2+ concentrations ([Ca2+]) of specific intracellular organelles in intact cells. After the binding of Ca2+ to three high-affinity binding sites, an irreversible reaction occurs leading to the emission of photons that is proportional to [Ca2+]. While native aequorin is suitable for measuring cytosolic [Ca2+] after cell stimulation in a range from 0.5 to 10 μM, it cannot be used in organelles where [Ca2+] is much higher, such as in the lumen of endoplasmic/sarcoplasmic reticulum (ER/SR) and mitochondria. However, some modifications made on aequorin itself or on coelenterazine, its lipophilic prosthetic luminophore, and the addition of targeting sequences or the fusion with resident proteins allowed the specific organelle localization and the measurements of intra-organelle Ca2+ levels. In the last years, the development of multiwell plate readers has opened the possibility to perform aequorin-based high-throughput screenings and has overcome some limitation of the standard method. Here we present the procedure for expressing, targeting, and reconstituting aequorin in intact cells and for measuring Ca2+ in the bulk cytosol, mitochondria, and ER by a high-throughput screening system.
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17
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Vicario M, Calì T. Measuring Ca 2+ Levels in Subcellular Compartments with Genetically Encoded GFP-Based Indicators. Methods Mol Biol 2019; 1925:31-42. [PMID: 30674014 DOI: 10.1007/978-1-4939-9018-4_3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
Ca2+ homeostasis is crucial for the entire life of eukaryotic cells from the beginning to the end. Mishandling in Ca2+ homeostasis is indeed linked with a large number of pathological conditions. Thus, the possibility to specifically monitor cellular calcium fluxes in different subcellular compartments represents a key tool to deeply understand the mechanisms involved in cellular dysfunctions. To cope with this need, several Ca2+ indicators have been developed allowing to accurately measure both basal Ca2+ concentration and agonist-induced Ca2+ signals in a wide spectrum of organelles. Among these, the genetically encoded GFP-based indicators are routinely used to measure Ca2+ transients thanks to their ability to change their spectral properties in response to Ca2+ binding. In this chapter, we will describe a protocol that utilizes the GCaMP6f probe targeted to mitochondria (4mtGCaMP) to measure mitochondrial calcium levels in resting conditions in HeLa cells. This method allows to easily and quickly register alterations of mitochondrial Ca2+ homeostasis in different cell populations and experimental settings, representing a precious tool to unravel the pathological pathways leading to pathogenic conditions.
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Affiliation(s)
- Mattia Vicario
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Tito Calì
- Department of Biomedical Sciences, University of Padua, Padua, Italy.
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18
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Su EY, Chu YL, Chueh FS, Ma YS, Peng SF, Huang WW, Liao CL, Huang AC, Chung JG. Bufalin Induces Apoptotic Cell Death in Human Nasopharyngeal Carcinoma Cells through Mitochondrial ROS and TRAIL Pathways. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2019; 47:237-257. [DOI: 10.1142/s0192415x19500125] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Abstract
The aim of this study was to investigate the effects of bufalin on human nasopharyngeal carcinoma NPC-TW 076 cells in vitro. Bufalin is a cardiotonic steroid and a key active ingredient of the Chinese medicine ChanSu. The extracts of Chansu are used for various cancer treatments in China. In the present study, bufalin induced cell morphological changes, decreased total cell viability and induced G2/M phase arrest of cell cycle in NPC-TW 076 cells. Results also indicated that bufalin induced chromatin condensation (cell apoptosis) and DNA damage by DAPI staining and comet assay, respectively. The induced apoptotic cell death was further confirmed by annexin-V/PI staining assay. In addition, bufalin also increased ROS and Ca[Formula: see text] production and decreased the levels of [Formula: see text]. Furthermore, the alterations of ROS, ER stress and apoptosis associated protein expressions were investigated by Western blotting. Results demonstrated that bufalin increased the expressions of ROS associated proteins, including SOD (Cu/Zn), SOD2 (Mn) and GST but decreased that of catalase. Bufalin increased ER stress associated proteins (GRP78, IRE-1[Formula: see text], IRE-1[Formula: see text], caspase-4, ATF-6[Formula: see text], Calpain 1, and GADD153). Bufalin increased the pro-apoptotic proteins Bax, and apoptotic associated proteins (cytochrome c, caspase-3, -8 and -9, AIF and Endo G) but reduced anti-apoptotic protein Bcl-2 in NPC-TW 076 cells. Furthermore, bufalin elevated the expressions of TRAIL-pathway associated proteins (TRAIL, DR4, DR5, and FADD). Based on these findings, we suggest bufalin induced apoptotic cell death via caspase-dependent, mitochondria-dependent and TRAIL pathways in human nasopharyngeal carcinoma NPC-TW 076 cells.
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Affiliation(s)
- En-Yun Su
- Department of Biological Science and Technology, China Medical University, Taichung, Taiwan
| | - Yung-Lin Chu
- Department of Food Science, International College, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - Fu-Shin Chueh
- Department of Food Nutrition and Health Biotechnology, Asia University, Taichung, Taiwan
| | - Yi-Shih Ma
- School of Chinese Medicine for Post-Baccalaureate, I-Shou University, Kaohsiung, Taiwan
- Department of Chinese Medicine, E-Da Hospital, Kaohsiung, Taiwan
| | - Shu-Fen Peng
- Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, Taiwan
| | - Wen-Wen Huang
- Department of Biological Science and Technology, China Medical University, Taichung, Taiwan
| | - Ching-Lung Liao
- College of Chinese Medicine, School of Post-Baccalaureate Chinese Medicine, China Medical University, Taichung, Taiwan
| | - An-Cheng Huang
- Department of Nursing, St. Mary’s Junior College of Medicine, Nursing and Management, Taiwan
| | - Jing-Gung Chung
- Department of Biological Science and Technology, China Medical University, Taichung, Taiwan
- Department of Biotechnology, Asia University, Taichung, Taiwan
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19
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Cardiac-specific Conditional Knockout of the 18-kDa Mitochondrial Translocator Protein Protects from Pressure Overload Induced Heart Failure. Sci Rep 2018; 8:16213. [PMID: 30385779 PMCID: PMC6212397 DOI: 10.1038/s41598-018-34451-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 10/18/2018] [Indexed: 01/17/2023] Open
Abstract
Heart failure (HF) is characterized by abnormal mitochondrial calcium (Ca2+) handling, energy failure and impaired mitophagy resulting in contractile dysfunction and myocyte death. We have previously shown that the 18-kDa mitochondrial translocator protein of the outer mitochondrial membrane (TSPO) can modulate mitochondrial Ca2+ uptake. Experiments were designed to test the role of the TSPO in a murine pressure-overload model of HF induced by transverse aortic constriction (TAC). Conditional, cardiac-specific TSPO knockout (KO) mice were generated using the Cre-loxP system. TSPO-KO and wild-type (WT) mice underwent TAC for 8 weeks. TAC-induced HF significantly increased TSPO expression in WT mice, associated with a marked reduction in systolic function, mitochondrial Ca2+ uptake, complex I activity and energetics. In contrast, TSPO-KO mice undergoing TAC had preserved ejection fraction, and exhibited fewer clinical signs of HF and fibrosis. Mitochondrial Ca2+ uptake and energetics were restored in TSPO KO mice, associated with decreased ROS, improved complex I activity and preserved mitophagy. Thus, HF increases TSPO expression, while preventing this increase limits the progression of HF, preserves ATP production and decreases oxidative stress, thereby preventing metabolic failure. These findings suggest that pharmacological interventions directed at TSPO may provide novel therapeutics to prevent or treat HF.
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20
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Wang P, Fernandez-Sanz C, Wang W, Sheu SS. Why don't mice lacking the mitochondrial Ca 2+ uniporter experience an energy crisis? J Physiol 2018; 598:1307-1326. [PMID: 30218574 DOI: 10.1113/jp276636] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 08/28/2018] [Indexed: 01/15/2023] Open
Abstract
Current dogma holds that the heart balances energy demand and supply effectively and sustainably by sequestering enough Ca2+ into mitochondria during heartbeats to stimulate metabolic enzymes in the tricarboxylic acid (TCA) cycle and electron transport chain (ETC). This process is called excitation-contraction-bioenergetics (ECB) coupling. Recent breakthroughs in identifying the mitochondrial Ca2+ uniporter (MCU) and its associated proteins have opened up new windows for interrogating the molecular mechanisms of mitochondrial Ca2+ homeostasis regulation and its role in ECB coupling. Despite remarkable progress made in the past 7 years, it has been surprising, almost disappointing, that germline MCU deficiency in mice with certain genetic background yields viable pups, and knockout of the MCU in adult heart does not cause lethality. Moreover, MCU deficiency results in few adverse phenotypes, normal performance, and preserved bioenergetics in the heart at baseline. In this review, we briefly assess the existing literature on mitochondrial Ca2+ homeostasis regulation and then we consider possible explanations for why MCU-deficient mice are spared from energy crises under physiological conditions. We propose that MCU and/or mitochondrial Ca2+ may have limited ability to set ECB coupling, that other mitochondrial Ca2+ handling mechanisms may play a role, and that extra-mitochondrial Ca2+ may regulate ECB coupling. Since the heart needs to regenerate a significant amount of ATP to assure the perpetuation of heartbeats, multiple mechanisms are likely to work in concert to match energy supply with demand.
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Affiliation(s)
- Pei Wang
- Mitochondria and Metabolism Center, Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA, 98109, USA
| | - Celia Fernandez-Sanz
- Center for Translational Medicine, Department of Medicine, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Wang Wang
- Mitochondria and Metabolism Center, Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA, 98109, USA
| | - Shey-Shing Sheu
- Center for Translational Medicine, Department of Medicine, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, 19107, USA
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21
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Boeck C, Gumpp AM, Calzia E, Radermacher P, Waller C, Karabatsiakis A, Kolassa IT. The association between cortisol, oxytocin, and immune cell mitochondrial oxygen consumption in postpartum women with childhood maltreatment. Psychoneuroendocrinology 2018; 96:69-77. [PMID: 29908404 DOI: 10.1016/j.psyneuen.2018.05.040] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 04/28/2018] [Accepted: 05/29/2018] [Indexed: 01/03/2023]
Abstract
Childhood maltreatment (CM) is associated with an increased risk for the development of psychiatric and somatic diseases in later life. Individual risk and resilience factors may, however, influence how deep psychological stress gets under the skin. We hypothesized that the stress-related hormone cortisol and the attachment-related hormone oxytocin constitute biological factors that might moderate the biological sequelae and long-term health outcomes associated with CM. As biological outcome, we thereby focused on immunocellular oxygen consumption, which we previously found to be increased with a higher severity of CM experiences. In a study cohort of N = 49 postpartum women, we investigated the interaction between CM experiences, serum cortisol and plasma oxytocin levels, and the cellular oxygen consumption of intact peripheral blood mononuclear cells (PBMC) by high-resolution respirometry. Regression analyses revealed a significant interaction between the severity of CM experiences and cortisol as well as oxytocin on cellular oxygen consumption of PBMC three months postpartum: higher cortisol levels were thereby associated with an increase in oxygen consumption related to basal mitochondrial respiration and ATP turnover, while oxygen consumption related to basal mitochondrial respiration and ATP turnover were reduced with higher oxytocin levels in individuals with higher CM severity. These associations were not seen among women with no or low CM experiences. Together, the results suggest that cortisol and oxytocin might be associated with opposite effects on CM-related alterations in the bioenergetic profile of peripheral immune cells.
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Affiliation(s)
- Christina Boeck
- Clinical & Biological Psychology, Institute of Psychology and Education, Ulm University, Albert-Einstein-Allee 47, 89081, Ulm, Germany.
| | - Anja Maria Gumpp
- Clinical & Biological Psychology, Institute of Psychology and Education, Ulm University, Albert-Einstein-Allee 47, 89081, Ulm, Germany
| | - Enrico Calzia
- Institute of Anesthesiological Pathophysiology and Process Engineering, University Hospital Ulm, Helmholtzstrasse 8/1, 89081, Ulm, Germany
| | - Peter Radermacher
- Institute of Anesthesiological Pathophysiology and Process Engineering, University Hospital Ulm, Helmholtzstrasse 8/1, 89081, Ulm, Germany
| | - Christiane Waller
- Department of Psychosomatic Medicine and Psychotherapy, University Hospital Ulm, Albert-Einstein-Allee 23, 89081, Ulm, Germany; Department of Psychosomatic Medicine and Psychotherapy, Paracelsus Medical University, Nuremberg General Hospital, 90419, Nuremberg, Germany
| | - Alexander Karabatsiakis
- Clinical & Biological Psychology, Institute of Psychology and Education, Ulm University, Albert-Einstein-Allee 47, 89081, Ulm, Germany
| | - Iris-Tatjana Kolassa
- Clinical & Biological Psychology, Institute of Psychology and Education, Ulm University, Albert-Einstein-Allee 47, 89081, Ulm, Germany
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22
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Kim HJ, Kim MR, Park JK, Lee YJ, Park B. Higher Serum Calcium Levels Are Associated with Preclinical Peripheral Arterial Disease among the Apparently Healthy Individuals. Korean J Fam Med 2018; 39:279-283. [PMID: 29972899 PMCID: PMC6166120 DOI: 10.4082/kjfm.17.0035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 07/11/2017] [Indexed: 11/04/2022] Open
Abstract
Background Epidemiological studies suggest that serum calcium levels correlate with cardiovascular events. An ankle-brachial index (ABI) between 0.9 and 1.00 is a surrogate estimation of preclinical peripheral arterial disease (PAD). Prior studies have shown that an ABI of 0.9–1.0 is also associated with endothelial dysfunction. Therefore, we sought to investigate the relationship between serum calcium levels and preclinical PAD in apparently healthy Korean individuals. Methods We evaluated the association between serum calcium levels and preclinical PAD in 596 participants (334 males, 262 females) in a health examination program. Preclinical PAD was defined by an ABI of 0.9–1.0. Multiple logistic regression analysis was used to determine whether the serum calcium level was an independent determinant of preclinical PAD. Results The overall prevalence of preclinical PAD was 14.3%. The mean age was 44.0±12.5 years in the non-PAD group and 48.3±11.4 years in the preclinical PAD group (P=0.001). After adjusting for age, gender, systolic blood pressure, fasting plasma glucose, high-density lipoprotein cholesterol, triglycerides, C-reactive protein, g-glutamyltransferase, uric acid, hypertension medication, diabetes medication, and hyperlipidemia medication, the odds ratio (95% confidence intervals) for preclinical PAD was 2.28 (1.02–5.11) with a 1-mg/dL increase in the serum calcium. Conclusion These findings suggest that increased serum calcium is independently and positively associated with preclinical PAD regardless of the presence of classic cardiovascular risk factors.
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Affiliation(s)
- Hyung-Jin Kim
- Department of Family Medicine, Yonsei University College of Medicine, Seoul, Korea
| | - Mi-Ri Kim
- Department of Family Medicine, Yonsei University College of Medicine, Seoul, Korea
| | - Jin-Kyung Park
- Department of Family Medicine, Yonsei University College of Medicine, Seoul, Korea
| | - Yong-Jae Lee
- Department of Family Medicine, Yonsei University College of Medicine, Seoul, Korea
| | - Byoungjin Park
- Department of Family Medicine, Yonsei University College of Medicine, Seoul, Korea
- Corresponding Author: Byoungjin Park Tel: +82-31-331-8710, Fax: +82-31-331-5551, E-mail:
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23
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Verma M, Wills Z, Chu CT. Excitatory Dendritic Mitochondrial Calcium Toxicity: Implications for Parkinson's and Other Neurodegenerative Diseases. Front Neurosci 2018; 12:523. [PMID: 30116173 PMCID: PMC6083050 DOI: 10.3389/fnins.2018.00523] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 07/12/2018] [Indexed: 12/22/2022] Open
Abstract
Dysregulation of calcium homeostasis has been linked to multiple neurological diseases. In addition to excitotoxic neuronal cell death observed following stroke, a growing number of studies implicate excess excitatory neuronal activity in chronic neurodegenerative diseases. Mitochondria function to rapidly sequester large influxes of cytosolic calcium through the activity of the mitochondrial calcium uniporter (MCU) complex, followed by more gradual release via calcium antiporters, such as NCLX. Increased cytosolic calcium levels almost invariably result in increased mitochondrial calcium uptake. While this response may augment mitochondrial respiration, limiting classic excitotoxic injury in the short term, recent studies employing live calcium imaging and molecular manipulation of calcium transporter activities suggest that mitochondrial calcium overload plays a key role in Parkinson’s disease (PD), Alzheimer’s disease (AD), amyotrophic lateral sclerosis (ALS), and related dementias [PD with dementia (PDD), dementia with Lewy bodies (DLB), and frontotemporal dementia (FTD)]. Herein, we review the literature on increased excitatory input, mitochondrial calcium dysregulation, and the transcriptional or post-translational regulation of mitochondrial calcium transport proteins, with an emphasis on the PD-linked kinases LRRK2 and PINK1. The impact on pathological dendrite remodeling and neuroprotective effects of manipulating MCU, NCLX, and LETM1 are reviewed. We propose that shortening and simplification of the dendritic arbor observed in neurodegenerative diseases occur through a process of excitatory mitochondrial toxicity (EMT), which triggers mitophagy and perisynaptic mitochondrial depletion, mechanisms that are distinct from classic excitotoxicity.
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Affiliation(s)
- Manish Verma
- Department of Pathology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Zachary Wills
- Department of Neurobiology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Charleen T Chu
- Department of Pathology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States.,Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States.,Pittsburgh Institute for Neurodegenerative Diseases, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States.,McGowan Institute for Regenerative Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States.,Center for Protein Conformational Diseases, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States.,Center for Neuroscience, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
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Jang DH, Seeger SC, Grady ME, Shofer FS, Eckmann DM. Mitochondrial dynamics and respiration within cells with increased open pore cytoskeletal meshes. Biol Open 2017; 6:1831-1839. [PMID: 29109116 PMCID: PMC5769657 DOI: 10.1242/bio.029009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The cytoskeletal architecture directly affects the morphology, motility, and tensional homeostasis of the cell. In addition, the cytoskeleton is important for mitosis, intracellular traffic, organelle motility, and even cellular respiration. The organelle responsible for a majority of the energy conversion for the cell, the mitochondrion, has a dependence on the cytoskeleton for mobility and function. In previous studies, we established that cytoskeletal inhibitors altered the movement of the mitochondria, their morphology, and their respiration in human dermal fibroblasts. Here, we use this protocol to investigate applicability of power law diffusion to describe mitochondrial locomotion, assessment of rates of fission and fusion in healthy and diseased cells, and differences in mitochondria locomotion in more open networks either in response to cytoskeletal destabilizers or by cell line. We found that mitochondria within fibrosarcoma cells and within fibroblast cells treated with an actin-destabilizing toxin resulted in increased net travel, increased average velocity, and increased diffusion of mitochondria when compared to control fibroblasts. Although the mitochondria within the fibrosarcoma travel further than mitochondria within their healthy counterparts, fibroblasts, the dependence on mitochondria for respiration is much lower with higher rates ofhydrogen peroxide production and was confirmed using the OROBOROS O2K. We also found that rates of fission and fusion of the mitochondria equilibrate despite significant alteration of the cytoskeleton. Rates ranged from 15% to 25%, where the highest rates were observed within the fibrosarcoma cell line. This result is interesting because the fibrosarcoma cell line does not have increased respiration metrics including when compared to fibroblast. Mitochondria travel further, faster, and have an increase in percent mitochondria splitting or joining while not dependent on the mitochondria for a majority of its energy production. This study illustrates the complex interaction between mitochondrial movement and respiration through the disruption of the cytoskeleton. Summary: We assessed the effect of cytoskeletal inhibitors and the use of a calcium ionophore as an additional stressor on mitochondrial motility and bioenergetic function in fibroblasts and fibrosarcoma cells.
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Affiliation(s)
- David H Jang
- Department of Emergency Medicine, Division of Medical Toxicology and Critical Care Medicine, Perelman School of Medicine, University of Pennsylvania, 3620 Hamilton Walk, John Morgan Building Room 12, Philadelphia, PA 19104, USA
| | - Sarah C Seeger
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Martha E Grady
- Department of Mechanical Engineering, University of Kentucky, 151 RGAN Building, Lexington, KY 40506, USA
| | - Frances S Shofer
- Department of Emergency Medicine, Division of Medical Toxicology and Critical Care Medicine, Perelman School of Medicine, University of Pennsylvania, 3620 Hamilton Walk, John Morgan Building Room 12, Philadelphia, PA 19104, USA
| | - David M Eckmann
- Department of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, 3620 Hamilton Walk, John Morgan Building Room 27B, Philadelphia, PA 19104, USA .,Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA
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25
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Rambold AS, Pearce EL. Mitochondrial Dynamics at the Interface of Immune Cell Metabolism and Function. Trends Immunol 2017; 39:6-18. [PMID: 28923365 DOI: 10.1016/j.it.2017.08.006] [Citation(s) in RCA: 208] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 08/04/2017] [Accepted: 08/11/2017] [Indexed: 12/31/2022]
Abstract
Immune cell differentiation and function are crucially dependent on specific metabolic programs dictated by mitochondria, including the generation of ATP from the oxidation of nutrients and supplying precursors for the synthesis of macromolecules and post-translational modifications. The many processes that occur in mitochondria are intimately linked to their morphology that is shaped by opposing fusion and fission events. Exciting evidence is now emerging that demonstrates reciprocal crosstalk between mitochondrial dynamics and metabolism. Metabolic cues can control the mitochondrial fission and fusion machinery to acquire specific morphologies that shape their activity. We review the dynamic properties of mitochondria and discuss how these organelles interlace with immune cell metabolism and function.
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Affiliation(s)
- Angelika S Rambold
- Center of Chronic Immunodeficiency, Medical Center, Freiburg University, Freiburg, Germany; Department of Developmental Immunology, Max-Planck Institute of Immunobiology and Epigenetics, Stübeweg 51, 79108 Freiburg, Germany.
| | - Erika L Pearce
- Department of Immunometabolism, Max-Planck Institute of Immunobiology and Epigenetics, Stübeweg 51, 79108 Freiburg, Germany
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26
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Gollihue JL, Rabchevsky AG. Prospects for therapeutic mitochondrial transplantation. Mitochondrion 2017; 35:70-79. [PMID: 28533168 DOI: 10.1016/j.mito.2017.05.007] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 03/31/2017] [Accepted: 05/17/2017] [Indexed: 01/11/2023]
Abstract
Mitochondrial dysfunction has been implicated in a multitude of diseases and pathological conditions- the organelles that are essential for life can also be major players in contributing to cell death and disease. Because mitochondria are so well established in our existence, being present in all cell types except for red blood cells and having the responsibility of providing most of our energy needs for survival, then dysfunctional mitochondria can elicit devastating cellular pathologies that can be widespread across the entire organism. As such, the field of "mitochondrial medicine" is emerging in which disease states are being targeted therapeutically at the level of the mitochondrion, including specific antioxidants, bioenergetic substrate additions, and membrane uncoupling agents. New and compelling research investigating novel techniques for mitochondrial transplantation to replace damaged or dysfunctional mitochondria with exogenous healthy mitochondria has shown promising results, including tissue sparing accompanied by increased energy production and decreased oxidative damage. Various experimental techniques have been attempted and each has been challenged to accomplish successful transplantation. The purpose of this review is to present the history of mitochondrial transplantation, the different techniques used for both in vitro and in vivo delivery, along with caveats and pitfalls that have been discovered along the way. Results from such pioneering studies are promising and could be the next big wave of "mitochondrial medicine" once technical hurdles are overcome.
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Affiliation(s)
- Jenna L Gollihue
- University of Kentucky, Department of Physiology and Spinal Cord & Brain Injury Research Center, Lexington, KY 40536-0509, United States
| | - Alexander G Rabchevsky
- University of Kentucky, Department of Physiology and Spinal Cord & Brain Injury Research Center, Lexington, KY 40536-0509, United States.
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Zhang Y, Fang F, Fan K, Zhang Y, Zhang J, Guo H, Yu P, Ma J. Effective cytotoxic activity of OSW-1 on colon cancer by inducing apoptosis in vitro and in vivo. Oncol Rep 2017; 37:3509-3519. [PMID: 28440433 DOI: 10.3892/or.2017.5582] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Accepted: 02/22/2017] [Indexed: 11/05/2022] Open
Abstract
As a natural compound, Ornithogalum caudatum Ait is primarily used as an anti-inflammatory and antitumor agent in Chinese folk medicine. In 1992, OSW-1 was isolated from this compound, which is a new member of cholestane saponin family. In numerous recent studies, OSW-1 has been shown to have powerful cytotoxic anticancer effects against various malignant cells. However, the therapeutic efficacy of OSW-1 on colon cancer and the underlying mechanism are not understood. To explore the mechanism underlying OSW-1 in antitumor therapy, a therapeutic function analysis of OSW-1 on colon cancer was performed in vitro and in vivo. It was shown that with low toxicity on normal colonic cells, OSW-1 suppresses colon cancer cells in vitro and this inhibition was via the intrinsic apoptotic pathway, which increased cellular calcium, changed mitochondrial membrane potential, disrupted mitochondrial morphology, and led to the release of cytochrome c and the activation of caspase-3. Furthermore, in a nude mouse model, OSW-1 had a powerful effect on suppressing colon tumor proliferation without significant side effects through the apoptosis pathway. Taken together, these results demonstrate that OSW-1 is a potential drug for colon cancer treatment.
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Affiliation(s)
- Yanhong Zhang
- Graduate School of Dalian Medical University, Dalian, Liaoning 116044, P.R. China
| | - Fengqi Fang
- The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116011, P.R. China
| | - Kai Fan
- Department of Anatomy, Dalian Medical University, Dalian, Liaoning 116044, P.R. China
| | - Yanli Zhang
- Department of Anatomy, Dalian Medical University, Dalian, Liaoning 116044, P.R. China
| | - Jie Zhang
- The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116011, P.R. China
| | - Huishu Guo
- Centralab, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116044, P.R. China
| | - Peiyao Yu
- The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116011, P.R. China
| | - Jianmei Ma
- Department of Anatomy, Dalian Medical University, Dalian, Liaoning 116044, P.R. China
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28
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Gilda JE, Gomes AV. Proteasome dysfunction in cardiomyopathies. J Physiol 2017; 595:4051-4071. [PMID: 28181243 DOI: 10.1113/jp273607] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 01/13/2017] [Indexed: 12/16/2022] Open
Abstract
The ubiquitin-proteasome system (UPS) plays a critical role in removing unwanted intracellular proteins and is involved in protein quality control, signalling and cell death. Because the heart is subject to continuous metabolic and mechanical stress, the proteasome plays a particularly important role in the heart, and proteasome dysfunction has been suggested as a causative factor in cardiac dysfunction. Proteasome impairment has been detected in cardiomyopathies, heart failure, myocardial ischaemia, and hypertrophy. Proteasome inhibition is also sufficient to cause cardiac dysfunction in healthy pigs, and patients using a proteasome inhibitor for cancer therapy have a higher incidence of heart failure. In this Topical Review we discuss the experimental data which suggest UPS dysfunction is a common feature of cardiomyopathies, with an emphasis on hypertrophic cardiomyopathy caused by sarcomeric mutations. We also propose potential mechanisms by which cardiomyopathy-causing mutations may lead to proteasome impairment, such as altered calcium handling and increased oxidative stress due to mitochondrial dysfunction.
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Affiliation(s)
- Jennifer E Gilda
- Department of Neurobiology, Physiology, and Behaviour, University of California, Davis, CA, 95616, USA
| | - Aldrin V Gomes
- Department of Neurobiology, Physiology, and Behaviour, University of California, Davis, CA, 95616, USA.,Department of Physiology and Membrane Biology, University of California, Davis, CA, 95616, USA
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29
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Zhang Y, Avalos JL. Traditional and novel tools to probe the mitochondrial metabolism in health and disease. WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2017; 9. [PMID: 28067471 DOI: 10.1002/wsbm.1373] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 11/07/2016] [Accepted: 11/09/2016] [Indexed: 02/06/2023]
Abstract
Mitochondrial metabolism links energy production to other essential cellular processes such as signaling, cellular differentiation, and apoptosis. In addition to producing adenosine triphosphate (ATP) as an energy source, mitochondria are responsible for the synthesis of a myriad of important metabolites and cofactors such as tetrahydrofolate, α-ketoacids, steroids, aminolevulinic acid, biotin, lipoic acid, acetyl-CoA, iron-sulfur clusters, heme, and ubiquinone. Furthermore, mitochondria and their metabolism have been implicated in aging and several human diseases, including inherited mitochondrial disorders, cardiac dysfunction, heart failure, neurodegenerative diseases, diabetes, and cancer. Therefore, there is great interest in understanding mitochondrial metabolism and the complex relationship it has with other cellular processes. A large number of studies on mitochondrial metabolism have been conducted in the last 50 years, taking a broad range of approaches. In this review, we summarize and discuss the most commonly used tools that have been used to study different aspects of the metabolism of mitochondria: ranging from dyes that monitor changes in the mitochondrial membrane potential and pharmacological tools to study respiration or ATP synthesis, to more modern tools such as genetically encoded biosensors and trans-omic approaches enabled by recent advances in mass spectrometry, computation, and other technologies. These tools have allowed the large number of studies that have shaped our current understanding of mitochondrial metabolism. WIREs Syst Biol Med 2017, 9:e1373. doi: 10.1002/wsbm.1373 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Yanfei Zhang
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, USA
| | - José L Avalos
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, USA.,Andlinger Center for Energy and the Environment, Princeton University, Princeton, NJ, USA.,Department of Molecular Biology, Princeton University, Princeton, NJ, USA
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30
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Gyulkhandanyan AV, Allen DJ, Mykhaylov S, Lyubimov E, Ni H, Freedman J, Leytin V. Mitochondrial Inner Membrane Depolarization as a Marker of Platelet Apoptosis : Disclosure of Nonapoptotic Membrane Depolarization. Clin Appl Thromb Hemost 2016; 23:139-147. [PMID: 27637909 DOI: 10.1177/1076029616665924] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Availability of universal marker for the diagnosis of platelet apoptosis is an important but currently unresolved goal of platelet physiology investigations. Mitochondrial inner transmembrane potential (▵Ψm) depolarization is frequently used as a marker of apoptosis in nucleated cells and anucleate platelets. Since ▵Ψm depolarization in platelets is also frequently associated with concurrent induction of other apoptotic responses, it may appear that ▵Ψm depolarization is a good universal marker of platelet apoptosis. However, data presented in the current study indicate that this is incorrect. We report here fundamental differences in the effects of potassium ionophore valinomycin and calcium ionophore A23187 on human platelet apoptosis. Although both A23187-triggered and valinomycin-triggered ▵Ψm depolarization are strongly induced, the former is dependent on the opening of mitochondrial permeability transition pore (MPTP) and the latter is MPTP-independent. Furthermore, effects of calcium and potassium ionophores on other apoptotic events are also basically different. A23187 induces caspase-3 activation, proapoptotic Bax and Bak protein expression, phosphatidylserine exposure, and microparticle formation, whereas valinomycin does not induce these apoptotic manifestations. Discovery of targeted ▵Ψm depolarization not associated with apoptosis in valinomycin-treated platelets indicates that this marker should not be used as a single universal marker of platelet apoptosis in unknown experimental and clinical settings as it may lead to a false-positive apoptosis diagnosis.
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Affiliation(s)
- Armen V Gyulkhandanyan
- 1 Toronto Platelet Immunobiology Group, St. Michael's Hospital, Toronto, Ontario, Canada.,2 The Keenan Research Centre for Biomedical Science of St. Michael's Hospital, Toronto, Ontario, Canada
| | - David J Allen
- 1 Toronto Platelet Immunobiology Group, St. Michael's Hospital, Toronto, Ontario, Canada
| | - Sergiy Mykhaylov
- 1 Toronto Platelet Immunobiology Group, St. Michael's Hospital, Toronto, Ontario, Canada
| | - Elena Lyubimov
- 1 Toronto Platelet Immunobiology Group, St. Michael's Hospital, Toronto, Ontario, Canada
| | - Heyu Ni
- 1 Toronto Platelet Immunobiology Group, St. Michael's Hospital, Toronto, Ontario, Canada.,2 The Keenan Research Centre for Biomedical Science of St. Michael's Hospital, Toronto, Ontario, Canada.,3 Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada.,4 Department of Medicine, University of Toronto, Toronto, Ontario, Canada.,5 Canadian Blood Services, Ottawa, Ontario, Canada
| | - John Freedman
- 1 Toronto Platelet Immunobiology Group, St. Michael's Hospital, Toronto, Ontario, Canada.,2 The Keenan Research Centre for Biomedical Science of St. Michael's Hospital, Toronto, Ontario, Canada.,3 Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada.,4 Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Valery Leytin
- 1 Toronto Platelet Immunobiology Group, St. Michael's Hospital, Toronto, Ontario, Canada.,6 Department of Physics, Ryerson University, Toronto, Ontario, Canada
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31
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Zhou J, Dhakal K, Yi J. Mitochondrial Ca(2+) uptake in skeletal muscle health and disease. SCIENCE CHINA-LIFE SCIENCES 2016; 59:770-6. [PMID: 27430885 PMCID: PMC6168075 DOI: 10.1007/s11427-016-5089-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/16/2015] [Accepted: 06/07/2016] [Indexed: 11/09/2022]
Abstract
Muscle uses Ca2+ as a messenger to control contraction and relies on ATP to maintain the intracellular Ca2+ homeostasis. Mitochondria are the major sub-cellular organelle of ATP production. With a negative inner membrane potential, mitochondria take up Ca2+ from their surroundings, a process called mitochondrial Ca2+ uptake. Under physiological conditions, Ca2+ uptake into mitochondria promotes ATP production. Excessive uptake causes mitochondrial Ca2+ overload, which activates downstream adverse responses leading to cell dysfunction. Moreover, mitochondrial Ca2+ uptake could shape spatio-temporal patterns of intracellular Ca2+ signaling. Malfunction of mitochondrial Ca2+ uptake is implicated in muscle degeneration. Unlike non-excitable cells, mitochondria in muscle cells experience dramatic changes of intracellular Ca2+ levels. Besides the sudden elevation of Ca2+ level induced by action potentials, Ca2+ transients in muscle cells can be as short as a few milliseconds during a single twitch or as long as minutes during tetanic contraction, which raises the question whether mitochondrial Ca2+ uptake is fast and big enough to shape intracellular Ca2+ signaling during excitation-contraction coupling and creates technical challenges for quantification of the dynamic changes of Ca2+ inside mitochondria. This review focuses on characterization of mitochondrial Ca2+ uptake in skeletal muscle and its role in muscle physiology and diseases.
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Affiliation(s)
- Jingsong Zhou
- Kansas City University of Medicine and Bioscience, Dybedal Research Center, Kansas City, MO, 64106, USA.
| | - Kamal Dhakal
- Kansas City University of Medicine and Bioscience, Dybedal Research Center, Kansas City, MO, 64106, USA
| | - Jianxun Yi
- Kansas City University of Medicine and Bioscience, Dybedal Research Center, Kansas City, MO, 64106, USA
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32
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Ru Y, Zhou Y, Zhang Y. Transient receptor potential-canonical 3 modulates sperm motility and capacitation-associated protein tyrosine phosphorylation via [Ca2+]i mobilization. Acta Biochim Biophys Sin (Shanghai) 2015; 47:404-13. [PMID: 25910575 DOI: 10.1093/abbs/gmv025] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 02/02/2015] [Indexed: 02/07/2023] Open
Abstract
Ca(2+) signaling is pivotal for sperm maturation, including the processes of motility, capacitation, and the acrosome reaction. As a Ca(2+) conductor, transient receptor potential-canonical 3 (TRPC3) plays an important role in somatic cells. However, the function of TRPC3 in sperm is not well understood. Here, a pharmacological approach was used to investigate the role and mechanism of TPRC3 in sperm function. The TRPC3 antagonist Pyr3 could inhibit sperm motility and accelerate capacitation-associated protein tyrosine phosphorylation in a time- and dose-dependent manner, regardless of the presence or absence of Ca(2+) in the incubation medium. Further investigation revealed that sperm [Ca(2+)]i fell immediately once Pyr3 was added to Ca(2+)-free medium, and then gradually increased and returned to baseline levels. Moreover, the [Ca(2+)]i levels markedly elevated when sperm were incubated for 30 min in the presence of Pyr3; this change was subsequently accompanied by a significant reduction in sperm mitochondrial membrane potential. This study suggested that TRPC3 can modulate sperm function via mobilization of sperm [Ca(2+)]i.
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Affiliation(s)
- Yanfei Ru
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China University of Chinese Academy of Sciences, Beijing 100864, China
| | - Yuchuan Zhou
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Yonglian Zhang
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China Shanghai Institute of Planned Parenthood Research, Shanghai 200032, China
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33
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Mitochondrial Ca2+-dependent NLRP3 activation exacerbates the Pseudomonas aeruginosa-driven inflammatory response in cystic fibrosis. Nat Commun 2015; 6:6201. [PMID: 25648527 DOI: 10.1038/ncomms7201] [Citation(s) in RCA: 117] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 01/05/2015] [Indexed: 12/28/2022] Open
Abstract
The common pathological manifestation of cystic fibrosis (CF) is associated with an excessive lung inflammatory response characterized by interleukin-1β accumulation. CF airway epithelial cells show an exacerbated pro-inflammatory response to Pseudomonas aeruginosa; however, it is unclear whether this heightened inflammatory response is intrinsic to cells lacking CF transmembrane conductance regulator (CFTR). Here we demonstrate that the degree and quality of the inflammatory response in CF are supported by P. aeruginosa-dependent mitochondrial perturbation, in which flagellin is the inducer and mitochondrial Ca(2+) uniporter (MCU) is a signal-integrating organelle member for NLRP3 activation and IL-1β and IL-18 processing. Our work elucidates the regulation of the NLRP3 inflammasome by mitochondrial Ca(2+) in the P. aeruginosa-dependent inflammatory response and deepens our understanding of the significance of mitochondria in the Ca(2+)-dependent control of inflammation.
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34
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Kaufman RJ, Malhotra JD. Calcium trafficking integrates endoplasmic reticulum function with mitochondrial bioenergetics. BIOCHIMICA ET BIOPHYSICA ACTA 2014; 1843:2233-9. [PMID: 24690484 PMCID: PMC4285153 DOI: 10.1016/j.bbamcr.2014.03.022] [Citation(s) in RCA: 151] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Revised: 03/24/2014] [Accepted: 03/25/2014] [Indexed: 12/31/2022]
Abstract
Calcium homeostasis is central to all cellular functions and has been studied for decades. Calcium acts as a critical second messenger for both extracellular and intracellular signaling and is fundamental in cell life and death decisions (Berridge et al., 2000) [1]. The calcium gradient in the cell is coupled with an inherent ability of the divalent cation to reversibly bind multiple target biological molecules to generate an extremely versatile signaling system [2]. Calcium signals are used by the cell to control diverse processes such as development, neurotransmitter release, muscle contraction, metabolism, autophagy and cell death. "Cellular calcium overload" is detrimental to cellular health, resulting in massive activation of proteases and phospholipases leading to cell death (Pinton et al., 2008) [3]. Historically, cell death associated with calcium ion perturbations has been primarily recognized as necrosis. Recent evidence clearly associates changes in calcium ion concentrations with more sophisticated forms of cellular demise, including apoptosis (Kruman et al., 1998; Tombal et al., 1999; Lynch et al., 2000; Orrenius et al., 2003) [4-7]. Although the endoplasmic reticulum (ER) serves as the primary calcium store in the metazoan cell, dynamic calcium release to the cytosol, mitochondria, nuclei and other organelles orchestrate diverse coordinated responses. Most evidence supports that calcium transport from the ER to mitochondria plays a significant role in regulating cellular bioenergetics, production of reactive oxygen species, induction of autophagy and apoptosis. Recently, molecular identities that mediate calcium traffic between the ER and mitochondria have been discovered (Mallilankaraman et al., 2012a; Mallilankaraman et al., 2012b; Sancak et al., 2013)[8-10]. The next questions are how they are regulated for exquisite tight control of ER-mitochondrial calcium dynamics. This review attempts to summarize recent advances in the role of calcium in regulation of ER and mitochondrial function. This article is part of a Special Issue entitled: Calcium signaling in health and disease. Guest Editors: Geert Bultynck, Jacques Haiech, Claus W. Heizmann, Joachim Krebs, and Marc Moreau.
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35
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Schöneich C, Dremina E, Galeva N, Sharov V. Apoptosis in differentiating C2C12 muscle cells selectively targets Bcl-2-deficient myotubes. Apoptosis 2014; 19:42-57. [PMID: 24129924 DOI: 10.1007/s10495-013-0922-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Muscle cell apoptosis accompanies normal muscle development and regeneration, as well as degenerative diseases and aging. C2C12 murine myoblast cells represent a common model to study muscle differentiation. Though it was already shown that myogenic differentiation of C2C12 cells is accompanied by enhanced apoptosis in a fraction of cells, either the cell population sensitive to apoptosis or regulatory mechanisms for the apoptotic response are unclear so far. In the current study we characterize apoptotic phenotypes of different types of C2C12 cells at all stages of differentiation, and report here that myotubes of differentiated C2C12 cells with low levels of anti-apoptotic Bcl-2 expression are particularly vulnerable to apoptosis even though they are displaying low levels of pro-apoptotic proteins Bax, Bak and Bad. In contrast, reserve cells exhibit higher levels of Bcl-2 and high resistance to apoptosis. The transfection of proliferating myoblasts with Bcl-2 prior to differentiation did not protect against spontaneous apoptosis accompanying differentiation of C2C12 cells but led to Bcl-2 overexpression in myotubes and to significant protection from apoptotic cell loss caused by exposure to hydrogen peroxide. Overall, our data advocate for a Bcl-2-dependent mechanism of apoptosis in differentiated muscle cells. However, downstream processes for spontaneous and hydrogen peroxide induced apoptosis are not completely similar. Apoptosis in differentiating myoblasts and myotubes is regulated not through interaction of Bcl-2 with pro-apoptotic Bcl-2 family proteins such as Bax, Bak, and Bad.
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36
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Toxoplasma effector MAF1 mediates recruitment of host mitochondria and impacts the host response. PLoS Biol 2014; 12:e1001845. [PMID: 24781109 PMCID: PMC4004538 DOI: 10.1371/journal.pbio.1001845] [Citation(s) in RCA: 119] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Accepted: 03/21/2014] [Indexed: 11/23/2022] Open
Abstract
The intracellular human protozoan parasite Toxoplasma gondii uses a novel secreted protein to recruit host mitochondria and alter the host's response to infection. Recent information has revealed the functional diversity and importance of mitochondria in many cellular processes including orchestrating the innate immune response. Intriguingly, several infectious agents, such as Toxoplasma, Legionella, and Chlamydia, have been reported to grow within vacuoles surrounded by host mitochondria. Although many hypotheses have been proposed for the existence of host mitochondrial association (HMA), the causes and biological consequences of HMA have remained unanswered. Here we show that HMA is present in type I and III strains of Toxoplasma but missing in type II strains, both in vitro and in vivo. Analysis of F1 progeny from a type II×III cross revealed that HMA is a Mendelian trait that we could map. We use bioinformatics to select potential candidates and experimentally identify the polymorphic parasite protein involved, mitochondrial association factor 1 (MAF1). We show that introducing the type I (HMA+) MAF1 allele into type II (HMA−) parasites results in conversion to HMA+ and deletion of MAF1 in type I parasites results in a loss of HMA. We observe that the loss and gain of HMA are associated with alterations in the transcription of host cell immune genes and the in vivo cytokine response during murine infection. Lastly, we use exogenous expression of MAF1 to show that it binds host mitochondria and thus MAF1 is the parasite protein directly responsible for HMA. Our findings suggest that association with host mitochondria may represent a novel means by which Toxoplasma tachyzoites manipulate the host. The existence of naturally occurring HMA+ and HMA− strains of Toxoplasma, Legionella, and Chlamydia indicates the existence of evolutionary niches where HMA is either advantageous or disadvantageous, likely reflecting tradeoffs in metabolism, immune regulation, and other functions of mitochondria. Recent discoveries have revealed the remarkable functional diversity of mitochondria in roles other than energy production, including an integral role for mitochondria and their dynamics in the regulation of the innate immune response. Interestingly, host mitochondria are recruited to the membranes that surround certain intracellular bacteria and parasites during infection. To date, how and why this phenomenon occurs has been a mystery, although it has been proposed to provide a metabolic benefit to the microbes. Here we identify mitochondrial association factor 1 (MAF1) as the parasite protein that mediates the association between the protozoan pathogen Toxoplasma and host mitochondria during infection. We show that MAF1 is needed to recruit host mitochondria to the Toxoplasma-containing vacuole and that this process is associated with changes in the immune response in infected cells and animals. These findings show that recruitment and association with host mitochondria is an important means by which intracellular pathogens interface with their host. We also find that the cost–benefit outcome of altering mitochondrial function might differ between strains depending on the precise niche in which they evolved; for infectious agents, these differences likely reflect different host organisms.
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37
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Hill JM, De Stefani D, Jones AWE, Ruiz A, Rizzuto R, Szabadkai G. Measuring baseline Ca(2+) levels in subcellular compartments using genetically engineered fluorescent indicators. Methods Enzymol 2014; 543:47-72. [PMID: 24924127 DOI: 10.1016/b978-0-12-801329-8.00003-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Intracellular Ca(2+) signaling is involved in a series of physiological and pathological processes. In particular, an intimate crosstalk between bioenergetic metabolism and Ca(2+) homeostasis has been shown to determine cell fate in resting conditions as well as in response to stress. The endoplasmic reticulum and mitochondria represent key hubs of cellular metabolism and Ca(2+) signaling. However, it has been challenging to specifically detect highly localized Ca(2+) fluxes such as those bridging these two organelles. To circumvent this issue, various recombinant Ca(2+) indicators that can be targeted to specific subcellular compartments have been developed over the past two decades. While the use of these probes for measuring agonist-induced Ca(2+) signals in various organelles has been extensively described, the assessment of basal Ca(2+) concentrations within specific organelles is often disregarded, in spite of the fact that this parameter is vital for several metabolic functions, including the enzymatic activity of mitochondrial dehydrogenases of the Krebs cycle and protein folding in the endoplasmic reticulum. Here, we provide an overview on genetically engineered, organelle-targeted fluorescent Ca(2+) probes and outline their evolution. Moreover, we describe recently developed protocols to quantify baseline Ca(2+) concentrations in specific subcellular compartments. Among several applications, this method is suitable for assessing how changes in basal Ca(2+) levels affect the metabolic profile of cancer cells.
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Affiliation(s)
- Julia M Hill
- Department of Cell and Developmental Biology, Consortium for Mitochondrial Research, University College London, London, United Kingdom
| | - Diego De Stefani
- Department of Biomedical Sciences, CNR Neuroscience Institute, University of Padua, Padua, Italy
| | - Aleck W E Jones
- Department of Cell and Developmental Biology, Consortium for Mitochondrial Research, University College London, London, United Kingdom
| | - Asier Ruiz
- Department of Neurosciences, University of the Basque Country (UPV/EHU), Achúcarro Basque Center for Neuroscience-UPV/EHU, Leioa, Spain; Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas, (CIBERNED), Madrid, Spain
| | - Rosario Rizzuto
- Department of Biomedical Sciences, CNR Neuroscience Institute, University of Padua, Padua, Italy
| | - Gyorgy Szabadkai
- Department of Cell and Developmental Biology, Consortium for Mitochondrial Research, University College London, London, United Kingdom; Department of Biomedical Sciences, CNR Neuroscience Institute, University of Padua, Padua, Italy.
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Loss-of-function mutations in MICU1 cause a brain and muscle disorder linked to primary alterations in mitochondrial calcium signaling. Nat Genet 2013; 46:188-93. [PMID: 24336167 DOI: 10.1038/ng.2851] [Citation(s) in RCA: 276] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2013] [Accepted: 11/20/2013] [Indexed: 12/12/2022]
Abstract
Mitochondrial Ca(2+) uptake has key roles in cell life and death. Physiological Ca(2+) signaling regulates aerobic metabolism, whereas pathological Ca(2+) overload triggers cell death. Mitochondrial Ca(2+) uptake is mediated by the Ca(2+) uniporter complex in the inner mitochondrial membrane, which comprises MCU, a Ca(2+)-selective ion channel, and its regulator, MICU1. Here we report mutations of MICU1 in individuals with a disease phenotype characterized by proximal myopathy, learning difficulties and a progressive extrapyramidal movement disorder. In fibroblasts from subjects with MICU1 mutations, agonist-induced mitochondrial Ca(2+) uptake at low cytosolic Ca(2+) concentrations was increased, and cytosolic Ca(2+) signals were reduced. Although resting mitochondrial membrane potential was unchanged in MICU1-deficient cells, the mitochondrial network was severely fragmented. Whereas the pathophysiology of muscular dystrophy and the core myopathies involves abnormal mitochondrial Ca(2+) handling, the phenotype associated with MICU1 deficiency is caused by a primary defect in mitochondrial Ca(2+) signaling, demonstrating the crucial role of mitochondrial Ca(2+) uptake in humans.
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Vannuvel K, Renard P, Raes M, Arnould T. Functional and morphological impact of ER stress on mitochondria. J Cell Physiol 2013; 228:1802-18. [PMID: 23629871 DOI: 10.1002/jcp.24360] [Citation(s) in RCA: 122] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Accepted: 03/04/2013] [Indexed: 12/15/2022]
Abstract
Over the past years, knowledge and evidence about the existence of crosstalks between cellular organelles and their potential effects on survival or cell death have been constantly growing. More recently, evidence accumulated showing an intimate relationship between endoplasmic reticulum (ER) and mitochondria. These close contacts not only establish extensive physical links allowing exchange of lipids and calcium but they can also coordinate pathways involved in cell life and death. It is now obvious that ER dysfunction/stress and unfolded protein response (UPR) as well as mitochondria play major roles in apoptosis. However, while the effects of major ER stress on cell death have been largely studied and reviewed, it becomes more and more evident that cells might regularly deal with sublethal ER stress, a condition that does not necessarily lead to cell death but might affect the function/activity of other organelles such as mitochondria. In this review, we will particularly focus on these new, interesting and intriguing metabolic and morphological events that occur during the early adaptative phase of the ER stress, before the onset of cell death, and that remain largely unknown. Relevance and implication of these mitochondrial changes in response to ER stress conditions for human diseases such as type II diabetes and Alzheimer's disease will also be considered.
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Affiliation(s)
- Kayleen Vannuvel
- Laboratory of Biochemistry and Cellular Biology, URBC-NARILIS, University of Namur, Namur, Belgium
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40
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Melser S, Chatelain EH, Lavie J, Mahfouf W, Jose C, Obre E, Goorden S, Priault M, Elgersma Y, Rezvani HR, Rossignol R, Bénard G. Rheb regulates mitophagy induced by mitochondrial energetic status. Cell Metab 2013; 17:719-30. [PMID: 23602449 DOI: 10.1016/j.cmet.2013.03.014] [Citation(s) in RCA: 204] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 02/09/2013] [Accepted: 03/13/2013] [Indexed: 12/18/2022]
Abstract
Mitophagy has been recently described as a mechanism of elimination of damaged organelles. Although the regulation of the amount of mitochondria is a core issue concerning cellular energy homeostasis, the relationship between mitochondrial degradation and energetic activity has not yet been considered. Here, we report that the stimulation of mitochondrial oxidative phosphorylation enhances mitochondrial renewal by increasing its degradation rate. Upon high oxidative phosphorylation activity, we found that the small GTPase Rheb is recruited to the mitochondrial outer membrane. This mitochondrial localization of Rheb promotes mitophagy through a physical interaction with the mitochondrial autophagic receptor Nix and the autophagosomal protein LC3-II. Thus, Rheb-dependent mitophagy contributes to the maintenance of optimal mitochondrial energy production. Our data suggest that mitochondrial degradation contributes to a bulk renewal of the organelle in order to prevent mitochondrial aging and to maintain the efficiency of oxidative phosphorylation.
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Affiliation(s)
- Su Melser
- EA4576, Maladies Rares: Génétique et Métabolisme, 33000 Bordeaux Cedex, France
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Arvizo RR, Moyano DF, Saha S, Thompson MA, Bhattacharya R, Rotello VM, Prakash YS, Mukherjee P. Probing novel roles of the mitochondrial uniporter in ovarian cancer cells using nanoparticles. J Biol Chem 2013; 288:17610-8. [PMID: 23615904 DOI: 10.1074/jbc.m112.435206] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Nanoparticles provide a potent tool for targeting and understanding disease mechanisms. In this regard, cancer cells are surprisingly resistant to the expected toxic effects of positively charged gold nanoparticles ((+)AuNPs). Our investigations led to the identification of MICU1, regulator of mitochondrial calcium uniporter, as a key molecule conferring cancer cells with resistance to (+)AuNPs. The increase in cytosolic [Ca(2+)]cyto in malignant cells induced by (+)AuNPs is counteracted by MICU1, preventing cell death. Pharmacological or siRNA-mediated inhibition of mitochondrial Ca(+2) entry leads to endoplasmic reticulum stress and sensitizes cancer cells to (+)AuNP-induced cytotoxicity. Silencing MICU1 decreases Bcl-2 expression and increases caspase-3 activity and cytosolic cytochrome c levels, thus initiating the mitochondrial pathway for apoptosis: effects further enhanced by (+)AuNPs. This study highlights the potential of nanomaterials as a tool to broaden our understanding of cellular processes, establishes MICU1 as a novel regulator of the machinery in cancer cells that prevents apoptosis, and emphasizes the need to synergize nanoparticle design with understanding of mitochondrial machinery for enhancing targeted cellular toxicity.
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Affiliation(s)
- Rochelle R Arvizo
- Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA
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Miglio G, Rosa AC, Rattazzi L, Grange C, Camussi G, Fantozzi R. Protective effects of peroxisome proliferator-activated receptor agonists on human podocytes: proposed mechanisms of action. Br J Pharmacol 2013; 167:641-53. [PMID: 22594945 DOI: 10.1111/j.1476-5381.2012.02026.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND AND PURPOSE Peroxisome proliferator-activated receptor (PPAR) agonists exert anti-albuminuric effects. However, the nephroprotective effects of these drugs remain to be fully understood. We have investigated whether gemfibrozil, GW0742 and pioglitazone protect human podocytes against nutrient deprivation (ND)-induced cell death and the role of mitochondrial biogenesis as a cytoprotective process. EXPERIMENTAL APPROACH Immortalized human podocytes were pre-treated with the PPAR agonists and exposed to ND (5 h) under normoxia, hypoxia or in the presence of pyruvate. Cell death was measured at the end of the ND and of the recovery phase (24 h). Mitochondrial mass, cytochrome c oxidase (COX) subunits 1 and 4 were measured as markers of mitochondrial cell content, while membrane potential as an index of mitochondrial function. PGC-1α, NRF1 and Tfam expression was studied, as crucial regulators of mitochondrial biogenesis. KEY RESULTS Cell pre-treatment with gemfibrozil, GW0742, or pioglitazone significantly decreased the ND-induced cell loss, necrosis and apoptosis. These effects were attenuated by hypoxia and potentiated by pyruvate. Pre-treatment with these drugs significantly increased mitochondrial cell content, while it did not affect mitochondrial function. In all these experiments pioglitazone exerted significantly larger effects than gemfibrozil or GW0742. CONCLUSIONS AND IMPLICATIONS Gemfibrozil, GW0742 and pioglitazone may exert direct protective effects on human podocytes. Mitochondrial biogenesis is a cell response to the PPAR agonists related to their cytoprotective activity. These results provide a mechanistic support to the clinical evidence indicating PPAR agonists as disease-modifying agents for glomerular diseases.
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Affiliation(s)
- Gianluca Miglio
- Dipartimento di Scienza e Tecnologia del Farmaco, Università degli Studi di Torino, Turin, Italy.
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Prevarskaya N, Skryma R, Shuba Y. Targeting Ca2+transport in cancer: close reality or long perspective? Expert Opin Ther Targets 2013; 17:225-41. [DOI: 10.1517/14728222.2013.741594] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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44
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Heat-shock proteins attenuate SERCA inactivation by the anti-apoptotic protein Bcl-2: possible implications for the ER Ca2+-mediated apoptosis. Biochem J 2012; 444:127-39. [PMID: 22360692 DOI: 10.1042/bj20111114] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
We have demonstrated previously that Bcl-2 and Bcl-2Δ21, a C-terminally truncated Bcl-2 sequence, inactivate SERCA (sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPase) 1 in isolated SR (sarcoplasmic reticulum), accompanied by a translocation from CRDs (caveolae-related domains) of the SR. In the present study, we obtained evidence for the interaction of Bcl-2 with SERCA2b in C2C12 myoblasts and HEK (human embryonic kidney)-293 cells. Bcl-2 and SERCA2b co-immunoprecipitated from lysate and microsomal fractions of Bcl-2-overexpressing cells. However, Bcl-2 overexpression resulted only in a slight translocation from the CRDs and no significant SERCA inactivation. In isolated HEK-293 cell microsomes, incubation with Bcl-2Δ21 afforded SERCA2b inactivation and some translocation. HSP (heat-shock protein) 70, HSP90, HSP27 and α-crystallin attenuated Bcl-2Δ21-dependent SERCA2b inactivation. An in vitro mechanistic study with the SERCA1 isoform shows that HSP70 (i) protects SERCA1 from the inactivation by Bcl-2Δ21, (ii) inhibits SERCA1 translocation from CRD fractions, and (iii) prevents the Bcl-2Δ21-dependent loss of FITC labelling. Our data demonstrate that the mechanism of SERCA inactivation by Bcl-2 established in vitro for the SERCA1 isoform can be extended to the main housekeeping SERCA2b isoform, and that functional interactions of SERCA2b and Bcl-2 in the cell may be modulated by HSP70 and other chaperones and stress-regulated proteins.
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45
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Direct monitoring of mitochondrial calcium levels in cultured cardiac myocytes using a novel fluorescent indicator protein, GCaMP2-mt. Int J Cardiol 2012; 158:225-34. [DOI: 10.1016/j.ijcard.2011.01.034] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2010] [Revised: 12/08/2010] [Accepted: 01/11/2011] [Indexed: 12/27/2022]
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Calì T, Ottolini D, Brini M. Mitochondrial Ca(2+) and neurodegeneration. Cell Calcium 2012; 52:73-85. [PMID: 22608276 PMCID: PMC3396847 DOI: 10.1016/j.ceca.2012.04.015] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2012] [Revised: 04/18/2012] [Accepted: 04/20/2012] [Indexed: 12/16/2022]
Abstract
Mitochondria are essential for ensuring numerous fundamental physiological processes such as cellular energy, redox balance, modulation of Ca2+ signaling and important biosynthetic pathways. They also govern the cell fate by participating in the apoptosis pathway. The mitochondrial shape, volume, number and distribution within the cells are strictly controlled. The regulation of these parameters has an impact on mitochondrial function, especially in the central nervous system, where trafficking of mitochondria is critical to their strategic intracellular distribution, presumably according to local energy demands. Thus, the maintenance of a healthy mitochondrial population is essential to avoid the impairment of the processes they regulate: for this purpose, cells have developed mechanisms involving a complex system of quality control to remove damaged mitochondria, or to renew them. Defects of these processes impair mitochondrial function and lead to disordered cell function, i.e., to a disease condition. Given the standard role of mitochondria in all cells, it might be expected that their dysfunction would give rise to similar defects in all tissues. However, damaged mitochondrial function has pleiotropic effects in multicellular organisms, resulting in diverse pathological conditions, ranging from cardiac and brain ischemia, to skeletal muscle myopathies to neurodegenerative diseases. In this review, we will focus on the relationship between mitochondrial (and cellular) derangements and Ca2+ dysregulation in neurodegenerative diseases, emphasizing the evidence obtained in genetic models. Common patterns, that recognize the derangement of Ca2+ and energy control as a causative factor, have been identified: advances in the understanding of the molecular regulation of Ca2+ homeostasis, and on the ways in which it could become perturbed in neurological disorders, may lead to the development of therapeutic strategies that modulate neuronal Ca2+ signaling.
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Affiliation(s)
- Tito Calì
- Department of Comparative Biomedicine and Food Science, University of Padova, Padova, Italy
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47
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Garcia-Dorado D, Ruiz-Meana M, Inserte J, Rodriguez-Sinovas A, Piper HM. Calcium-mediated cell death during myocardial reperfusion. Cardiovasc Res 2012; 94:168-80. [PMID: 22499772 DOI: 10.1093/cvr/cvs116] [Citation(s) in RCA: 217] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Reperfusion may induce additional cell death in patients with acute myocardial infarction receiving primary angioplasty or thrombolysis. Altered intracellular Ca(2+) handling was initially considered an essential mechanism of reperfusion-induced cardiomyocyte death. However, more recent studies have demonstrated the importance of Ca(2+)-independent mechanisms that converge on mitochondrial permeability transition (MPT) and are shared by cardiomyocytes and other cell types. This article analyses the importance of Ca(2+)-dependent cell death in light of these new observations. Altered Ca(2+) handling includes increased cytosolic Ca(2+) levels, leading to activation of calpain-mediated proteolysis and sarcoplasmic reticulum-driven oscillations; this can induce hypercontracture, but also MPT due to the privileged Ca(2+) transfer between sarcoplasmic reticulum and mitochondria through cytosolic Ca(2+) microdomains. In the opposite direction, permeability transition can worsen altered Ca(2+) handling and favour hypercontracture. Ca(2+) appears to play an important role in cell death during the initial minutes of reperfusion, particularly after brief periods of ischaemia. Developing effective and safe treatments to prevent Ca(2+)-mediated cardiomyocyte death in patients with transient ischaemia, by targeting Ca(2+) influx, intracellular Ca(2+) handling, or Ca(2+)-induced cell death effectors, is an unmet challenge with important therapeutic implications and large potential clinical impact.
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48
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Davies SA, Overend G, Sebastian S, Cundall M, Cabrero P, Dow JAT, Terhzaz S. Immune and stress response 'cross-talk' in the Drosophila Malpighian tubule. JOURNAL OF INSECT PHYSIOLOGY 2012; 58:488-497. [PMID: 22306292 DOI: 10.1016/j.jinsphys.2012.01.008] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2011] [Revised: 01/10/2012] [Accepted: 01/12/2012] [Indexed: 05/31/2023]
Abstract
The success of insects is in large part due to their ability to survive environmental stress, including heat, cold, and dehydration. Insects are also exposed to infection, osmotic or oxidative stress, and to xenobiotics or toxins. The molecular mechanisms of stress sensing and response have been widely investigated in mammalian cell lines, and the area of stress research is now so vast to be beyond the scope of a single review article. However, the mechanisms by which stress inputs to the organism are sensed and integrated at the tissue and cellular level are less well understood. Increasingly, common molecular events between immune and other stress responses are observed in vivo; and much of this work stems of efforts in insect molecular science and physiology. We describe here the current knowledge in the area of immune and stress signalling and response at the level of the organism, tissue and cell, focussing on a key epithelial tissue in insects, the Malpighian tubule, and drawing together the known pathways that modulate responses to different stress insults. The tubules are critical for insect survival and are increasingly implicated in responses to multiple and distinct stress inputs. Importantly, as tubule function is central to survival, they are potentially key targets for insect control, which will be facilitated by increased understanding of the complexities of stress signalling in the organism.
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Affiliation(s)
- Shireen-Anne Davies
- Institute of Molecular Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK.
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Yi J, Ma C, Li Y, Weisleder N, Ríos E, Ma J, Zhou J. Mitochondrial calcium uptake regulates rapid calcium transients in skeletal muscle during excitation-contraction (E-C) coupling. J Biol Chem 2011; 286:32436-43. [PMID: 21795684 DOI: 10.1074/jbc.m110.217711] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Defective coupling between sarcoplasmic reticulum and mitochondria during control of intracellular Ca(2+) signaling has been implicated in the progression of neuromuscular diseases. Our previous study showed that skeletal muscles derived from an amyotrophic lateral sclerosis (ALS) mouse model displayed segmental loss of mitochondrial function that was coupled with elevated and uncontrolled sarcoplasmic reticulum Ca(2+) release activity. The localized mitochondrial defect in the ALS muscle allows for examination of the mitochondrial contribution to Ca(2+) removal during excitation-contraction coupling by comparing Ca(2+) transients in regions with normal and defective mitochondria in the same muscle fiber. Here we show that Ca(2+) transients elicited by membrane depolarization in fiber segments with defective mitochondria display an ~10% increased amplitude. These regional differences in Ca(2+) transients were abolished by the application of 1,2-bis(O-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid, a fast Ca(2+) chelator that reduces mitochondrial Ca(2+) uptake. Using a mitochondria-targeted Ca(2+) biosensor (mt11-YC3.6) expressed in ALS muscle fibers, we monitored the dynamic change of mitochondrial Ca(2+) levels during voltage-induced Ca(2+) release and detected a reduced Ca(2+) uptake by mitochondria in the fiber segment with defective mitochondria, which mirrored the elevated Ca(2+) transients in the cytosol. Our study constitutes a direct demonstration of the importance of mitochondria in shaping the cytosolic Ca(2+) signaling in skeletal muscle during excitation-contraction coupling and establishes that malfunction of this mechanism may contribute to neuromuscular degeneration in ALS.
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Affiliation(s)
- Jianxun Yi
- Department of Molecular Biophysics and Physiology, Rush University School of Medicine, Chicago, Illinois 60612, USA
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50
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Strokin M, Sergeeva M, Reiser G. Proinflammatory treatment of astrocytes with lipopolysaccharide results in augmented Ca2+ signaling through increased expression of via phospholipase A2 (iPLA2). Am J Physiol Cell Physiol 2010; 300:C542-9. [PMID: 21178110 DOI: 10.1152/ajpcell.00428.2010] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Many Ca(2+)-regulated intracellular processes are involved in the development of neuroinflammation. However, the changes of Ca(2+) signaling in the brain under inflammatory conditions were hardly studied. ATP-induced Ca(2+) signaling is a central event of signal transmission in astrocytic networks. We investigated primary astrocytes after proinflammatory stimulation with lipopolysaccharide (LPS; 100 ng/ml) for 6-24 h. We reveal that Ca(2+) responses to purinergic ATP stimulation are significantly increased in amplitude and duration after stimulation with LPS. We detected that increased amplitudes of Ca(2+) responses to ATP in LPS-treated astrocytes can be explained by substantial increase of Ca(2+) load in stores in endoplasmic reticulum. The mechanism implies enhanced Ca(2+) store refilling due to the amplification of capacitative Ca(2+) entry. The reason for the increased duration of Ca(2+) responses in LPS-treated cells is also the amplified capacitative Ca(2+) entry. Next, we established that the molecular mechanism for the LPS-induced amplification of Ca(2+) responses in astrocytes is increased expression and activity of VIA phospholipase A(2) (VIA iPLA(2)). Indeed, both gene silencing with specific small interfering RNA and pharmacological inhibition of VIA iPLA(2) with S-bromoenol lactone reduced the load of the Ca(2+) stores and caused a decrease in the amplitudes of Ca(2+) responses in LPS-treated astrocytes to values, which were comparable with those in untreated cells. Our findings highlight a novel regulatory role of VIA iPLA(2) in development of inflammation in brain. We suggest that this enzyme might be a possible target for treatment of pathologies related to brain inflammation.
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Affiliation(s)
- Mikhail Strokin
- Institut für Neurobiochemie, Otto-von-Guericke-Universität Magdeburg, Medizinische Fakultät, Leipziger Straße 44, 39120 Magdeburg, Germany
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