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Léger A, Cormier SB, Blanchard A, Menail HA, Pichaud N. Investigating the thermal sensitivity of key enzymes involved in the energetic metabolism of three insect species. J Exp Biol 2024; 227:jeb247221. [PMID: 38680096 DOI: 10.1242/jeb.247221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 04/16/2024] [Indexed: 05/01/2024]
Abstract
The metabolic responses of insects to high temperatures have been linked to their mitochondrial substrate oxidation capacity. However, the mechanism behind this mitochondrial flexibility is not well understood. Here, we used three insect species with different thermal tolerances (the honey bee, Apis mellifera; the fruit fly, Drosophila melanogaster; and the potato beetle, Leptinotarsa decemlineata) to characterize the thermal sensitivity of different metabolic enzymes. Specifically, we measured activity of enzymes involved in glycolysis (hexokinase, HK; pyruvate kinase, PK; and lactate dehydrogenase, LDH), pyruvate oxidation and the tricarboxylic acid cycle (pyruvate dehydrogenase, PDH; citrate synthase, CS; malate dehydrogenase, MDH; and aspartate aminotransferase, AAT), and the electron transport system (Complex I, CI; Complex II, CII; mitochondrial glycerol-3-phosphate dehydrogenase, mG3PDH; proline dehydrogenase, ProDH; and Complex IV, CIV), as well as that of ATP synthase (CV) at 18, 24, 30, 36, 42 and 45°C. Our results show that at high temperature, all three species have significantly increased activity of enzymes linked to FADH2 oxidation, specifically CII and mG3PDH. In fruit flies and honey bees, this coincides with a significant decrease of PDH and CS activity, respectively, that would limit NADH production. This is in line with the switch from NADH-linked substrates to FADH2-linked substrates previously observed with mitochondrial oxygen consumption. Thus, we demonstrate that even though the three insect species have a different metabolic regulation, a similar response to high temperature involving CII and mG3PDH is observed, denoting the importance of these proteins for thermal tolerance in insects.
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Affiliation(s)
- Adèle Léger
- Department of Chemistry and Biochemistry, Université de Moncton, Moncton, NB, CanadaE1A 3E9
- New Brunswick Centre for Precision Medicine (NBCPM), Moncton, NB, CanadaE1C 8X3
| | - Simon B Cormier
- Department of Chemistry and Biochemistry, Université de Moncton, Moncton, NB, CanadaE1A 3E9
- New Brunswick Centre for Precision Medicine (NBCPM), Moncton, NB, CanadaE1C 8X3
| | - Arianne Blanchard
- Department of Chemistry and Biochemistry, Université de Moncton, Moncton, NB, CanadaE1A 3E9
- New Brunswick Centre for Precision Medicine (NBCPM), Moncton, NB, CanadaE1C 8X3
| | - Hichem A Menail
- Department of Chemistry and Biochemistry, Université de Moncton, Moncton, NB, CanadaE1A 3E9
- New Brunswick Centre for Precision Medicine (NBCPM), Moncton, NB, CanadaE1C 8X3
| | - Nicolas Pichaud
- Department of Chemistry and Biochemistry, Université de Moncton, Moncton, NB, CanadaE1A 3E9
- New Brunswick Centre for Precision Medicine (NBCPM), Moncton, NB, CanadaE1C 8X3
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Pirnia A, Maqdisi R, Mittal S, Sener M, Singharoy A. Perspective on Integrative Simulations of Bioenergetic Domains. J Phys Chem B 2024; 128:3302-3319. [PMID: 38562105 DOI: 10.1021/acs.jpcb.3c07335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Bioenergetic processes in cells, such as photosynthesis or respiration, integrate many time and length scales, which makes the simulation of energy conversion with a mere single level of theory impossible. Just like the myriad of experimental techniques required to examine each level of organization, an array of overlapping computational techniques is necessary to model energy conversion. Here, a perspective is presented on recent efforts for modeling bioenergetic phenomena with a focus on molecular dynamics simulations and its variants as a primary method. An overview of the various classical, quantum mechanical, enhanced sampling, coarse-grained, Brownian dynamics, and Monte Carlo methods is presented. Example applications discussed include multiscale simulations of membrane-wide electron transport, rate kinetics of ATP turnover from electrochemical gradients, and finally, integrative modeling of the chromatophore, a photosynthetic pseudo-organelle.
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Affiliation(s)
- Adam Pirnia
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287-1004, United States
| | - Ranel Maqdisi
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287-1004, United States
| | - Sumit Mittal
- VIT Bhopal University, Sehore 466114, Madhya Pradesh, India
| | - Melih Sener
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287-1004, United States
- Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Abhishek Singharoy
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287-1004, United States
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3
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Purandare N, Ghosalkar E, Grossman LI, Aras S. Mitochondrial Oxidative Phosphorylation in Viral Infections. Viruses 2023; 15:2380. [PMID: 38140621 PMCID: PMC10747082 DOI: 10.3390/v15122380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 11/26/2023] [Accepted: 11/29/2023] [Indexed: 12/24/2023] Open
Abstract
Mitochondria have been identified as the "powerhouse" of the cell, generating the cellular energy, ATP, for almost seven decades. Research over time has uncovered a multifaceted role of the mitochondrion in processes such as cellular stress signaling, generating precursor molecules, immune response, and apoptosis to name a few. Dysfunctional mitochondria resulting from a departure in homeostasis results in cellular degeneration. Viruses hijack host cell machinery to facilitate their own replication in the absence of a bonafide replication machinery. Replication being an energy intensive process necessitates regulation of the host cell oxidative phosphorylation occurring at the electron transport chain in the mitochondria to generate energy. Mitochondria, therefore, can be an attractive therapeutic target by limiting energy for viral replication. In this review we focus on the physiology of oxidative phosphorylation and on the limited studies highlighting the regulatory effects viruses induce on the electron transport chain.
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Affiliation(s)
- Neeraja Purandare
- Center for Molecular Medicine and Genetics, School of Medicine, Wayne State University, Detroit, MI 48201, USA; (N.P.); (E.G.); (L.I.G.)
| | - Esha Ghosalkar
- Center for Molecular Medicine and Genetics, School of Medicine, Wayne State University, Detroit, MI 48201, USA; (N.P.); (E.G.); (L.I.G.)
| | - Lawrence I. Grossman
- Center for Molecular Medicine and Genetics, School of Medicine, Wayne State University, Detroit, MI 48201, USA; (N.P.); (E.G.); (L.I.G.)
| | - Siddhesh Aras
- Center for Molecular Medicine and Genetics, School of Medicine, Wayne State University, Detroit, MI 48201, USA; (N.P.); (E.G.); (L.I.G.)
- Department of Obstetrics and Gynecology, School of Medicine, Wayne State University, Detroit, MI 48201, USA
- Department of Oncology, School of Medicine, Wayne State University, Detroit, MI 48201, USA
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Cerón DAC, de Alencar ER, Faroni LRD, Silva MVDA, Salvador DV. Toxicity of allyl isothiocyanate applied in systems with or without recirculation for controlling Sitophilus zeamais, Rhyzopertha dominica, and Tribolium castaneum in corn grains. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2023; 103:6373-6382. [PMID: 37205787 DOI: 10.1002/jsfa.12713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 05/01/2023] [Accepted: 05/19/2023] [Indexed: 05/21/2023]
Abstract
BACKGROUND The application of allyl isothiocyanate (AITC) has been proposed as an alternative to control stored-grain insects. However, AITC is a compound with a low diffusion coefficient, making its distribution throughout the grain mass difficult. Therefore, the objective of the present study was to evaluate the effectiveness of AITC applied in systems with or without recirculation for controlling Sitophilus zeamais (Mots. 1855) (Coleoptera: Curculionidae), Rhyzopertha dominica (Fabr.) (Coleoptera: Bostrichidae), and Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) infesting a corn grain mass. The assays used a polyvinyl chloride (PVC) prototype, dimensioned 1.60 m in length, 0.30 m in diameter, and a static capacity of 60 kg of grains. AITC toxicity to insects was evaluated at the base, 0.5 m from the base, and top of the grain column (1.0 m). Different concentrations of AITC were tested for an exposure period of 48 h. RESULTS In the system without AITC recirculation, insect mortality was verified only at the base of the grain column. However, insect mortality was considered uniform at the different positions of the column when the AITC recirculation system was adopted. In this system, there was also a marked reduction in the instantaneous population growth rate of S. zeamais, T. castaneum, and R. dominica, and a decrease in the dry matter loss of the grains, when the AITC concentrations were increased. CONCLUSION AITC recirculation proved to be a viable strategy for protecting grains against the species S. zeamais, R. dominica, and T. castaneum. AITC fumigation ultimately did not cause changes in grain quality. © 2023 Society of Chemical Industry.
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Pinho SA, Anjo SI, Cunha-Oliveira T. Metabolic Priming as a Tool in Redox and Mitochondrial Theragnostics. Antioxidants (Basel) 2023; 12:antiox12051072. [PMID: 37237939 DOI: 10.3390/antiox12051072] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 05/05/2023] [Accepted: 05/06/2023] [Indexed: 05/28/2023] Open
Abstract
Theragnostics is a promising approach that integrates diagnostics and therapeutics into a single personalized strategy. To conduct effective theragnostic studies, it is essential to create an in vitro environment that accurately reflects the in vivo conditions. In this review, we discuss the importance of redox homeostasis and mitochondrial function in the context of personalized theragnostic approaches. Cells have several ways to respond to metabolic stress, including changes in protein localization, density, and degradation, which can promote cell survival. However, disruption of redox homeostasis can lead to oxidative stress and cellular damage, which are implicated in various diseases. Models of oxidative stress and mitochondrial dysfunction should be developed in metabolically conditioned cells to explore the underlying mechanisms of diseases and develop new therapies. By choosing an appropriate cellular model, adjusting cell culture conditions and validating the cellular model, it is possible to identify the most promising therapeutic options and tailor treatments to individual patients. Overall, we highlight the importance of precise and individualized approaches in theragnostics and the need to develop accurate in vitro models that reflect the in vivo conditions.
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Affiliation(s)
- Sónia A Pinho
- CNC-Center for Neuroscience and Cell Biology, CIBB-Centre for Innovative Biomedicine and Biotechnology, University of Coimbra, 3060-197 Cantanhede, Portugal
- PDBEB-PhD Programme in Experimental Biology and Biomedicine, Institute of Interdisciplinary Research (IIIUC), University of Coimbra, 3004-504 Coimbra, Portugal
- IIIUC, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Sandra I Anjo
- CNC-Center for Neuroscience and Cell Biology, CIBB-Centre for Innovative Biomedicine and Biotechnology, University of Coimbra, 3060-197 Cantanhede, Portugal
- IIIUC, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Teresa Cunha-Oliveira
- CNC-Center for Neuroscience and Cell Biology, CIBB-Centre for Innovative Biomedicine and Biotechnology, University of Coimbra, 3060-197 Cantanhede, Portugal
- IIIUC, University of Coimbra, 3004-504 Coimbra, Portugal
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Yuan X, Ma W, Chen S, Wang H, Zhong C, Gao L, Cui Y, Pu D, Tan R, Wu J. CLPP inhibition triggers apoptosis in human ovarian granulosa cells via COX5A abnormality–Mediated mitochondrial dysfunction. Front Genet 2023; 14:1141167. [PMID: 37007963 PMCID: PMC10065195 DOI: 10.3389/fgene.2023.1141167] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 03/07/2023] [Indexed: 03/19/2023] Open
Abstract
Premature ovarian insufficiency (POI) is characterized by early loss of ovarian function before the age of 40 years. It is confirmed to have a strong and indispensable genetic component. Caseinolytic mitochondrial matrix peptidase proteolytic subunit (CLPP) is a key inducer of mitochondrial protein quality control for the clearance of misfolded or damaged proteins, which is necessary to maintain mitochondrial function. Previous findings have shown that the variation in CLPP is closely related to the occurrence of POI, which is consistent with our findings. This study identified a novel CLPP missense variant (c.628G > A) in a woman with POI who presented with secondary amenorrhea, ovarian dysfunction, and primary infertility. The variant was located in exon 5 and resulted in a change from alanine to threonine (p.Ala210Thr). Importantly, Clpp was mainly localized in the cytoplasm of mouse ovarian granulosa cells and oocytes, and was relatively highly expressed in granulosa cells. Moreover, the overexpression of c.628G > A variant in human ovarian granulosa cells decreased the proliferative capacity. Functional experiments revealed that the inhibition of CLPP decreased the content and activity of oxidative respiratory chain complex IV by affecting the degradation of aggregated or misfolded COX5A, leading to the accumulation of reactive oxygen species and reduction of mitochondrial membrane potential, ultimately activating the intrinsic apoptotic pathways. The present study demonstrated that CLPP affected the apoptosis of granulosa cells, which might be one of the mechanisms by which CLPP aberrations led to the development of POI.
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Affiliation(s)
- Xiong Yuan
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
- State Key Laboratory of Reproductive Medicine, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Wenjie Ma
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
- State Key Laboratory of Reproductive Medicine, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Shuping Chen
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
- State Key Laboratory of Reproductive Medicine, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Huiyuan Wang
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
- State Key Laboratory of Reproductive Medicine, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Chenyi Zhong
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
- State Key Laboratory of Reproductive Medicine, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Li Gao
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
- State Key Laboratory of Reproductive Medicine, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Yugui Cui
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
- State Key Laboratory of Reproductive Medicine, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Danhua Pu
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
- State Key Laboratory of Reproductive Medicine, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Rongrong Tan
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
- State Key Laboratory of Reproductive Medicine, School of Public Health, Nanjing Medical University, Nanjing, China
- *Correspondence: Jie Wu, ; Rongrong Tan,
| | - Jie Wu
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
- State Key Laboratory of Reproductive Medicine, School of Public Health, Nanjing Medical University, Nanjing, China
- *Correspondence: Jie Wu, ; Rongrong Tan,
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Weaver RJ, Rabinowitz S, Thueson K, Havird JC. Genomic Signatures of Mitonuclear Coevolution in Mammals. Mol Biol Evol 2022; 39:6775223. [PMID: 36288802 PMCID: PMC9641969 DOI: 10.1093/molbev/msac233] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Mitochondrial (mt) and nuclear-encoded proteins are integrated in aerobic respiration, requiring co-functionality among gene products from fundamentally different genomes. Different evolutionary rates, inheritance mechanisms, and selection pressures set the stage for incompatibilities between interacting products of the two genomes. The mitonuclear coevolution hypothesis posits that incompatibilities may be avoided if evolution in one genome selects for complementary changes in interacting genes encoded by the other genome. Nuclear compensation, in which deleterious mtDNA changes are offset by compensatory nuclear changes, is often invoked as the primary mechanism for mitonuclear coevolution. Yet, direct evidence supporting nuclear compensation is rare. Here, we used data from 58 mammalian species representing eight orders to show strong correlations between evolutionary rates of mt and nuclear-encoded mt-targeted (N-mt) proteins, but not between mt and non-mt-targeted nuclear proteins, providing strong support for mitonuclear coevolution across mammals. N-mt genes with direct mt interactions also showed the strongest correlations. Although most N-mt genes had elevated dN/dS ratios compared to mt genes (as predicted under nuclear compensation), N-mt sites in close contact with mt proteins were not overrepresented for signs of positive selection compared to noncontact N-mt sites (contrary to predictions of nuclear compensation). Furthermore, temporal patterns of N-mt and mt amino acid substitutions did not support predictions of nuclear compensation, even in positively selected, functionally important residues with direct mitonuclear contacts. Overall, our results strongly support mitonuclear coevolution across ∼170 million years of mammalian evolution but fail to support nuclear compensation as the major mode of mitonuclear coevolution.
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Affiliation(s)
- Ryan J Weaver
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA.,Department of Natural Resource Ecology and Management, Iowa State University, Ames, IA
| | | | - Kiley Thueson
- Department of Integrative Biology, University of Texas, Austin, TX
| | - Justin C Havird
- Department of Integrative Biology, University of Texas, Austin, TX
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A comparative and ontogenetic examination of mitochondrial function in Antarctic notothenioid species. J Comp Physiol B 2022; 192:737-750. [PMID: 36104549 PMCID: PMC9550766 DOI: 10.1007/s00360-022-01461-6] [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: 02/18/2022] [Revised: 07/25/2022] [Accepted: 08/30/2022] [Indexed: 12/03/2022]
Abstract
Notothenioidei fishes have evolved under stable cold temperatures; however, ocean conditions are changing globally, with polar regions poised to experience the greatest changes in environmental factors, such as warming. These stressors have the potential to dramatically affect energetic demands, and the persistence of the notothenioids will be dependent on metabolic capacity, or the ability to match energy supply with energy demand, to restore homeostasis in the face of changing climate conditions. In this study we examined aerobic metabolic capacity in three species, Trematomus bernacchii, T. pennellii and T. newnesi, and between two life stages, juvenile and adult, by assessing mitochondrial function of permeabilized cardiac fibers. Respiratory capacity differed among the adult notothenioids in this study, with greater oxidative phosphorylation (OXPHOS) respiration in the pelagic T. newnesi than the benthic T. bernacchii and T. pennellii. The variation in mitochondrial respiratory capacity was likely driven by differences in the mitochondrial content, as measured by citrate synthase activity, which was the highest in T. newnesi. In addition to high OXPHOS, T. newnesi exhibited lower LEAK respiration, resulting in greater mitochondrial efficiency than either T. bernacchii or T. pennellii. Life stage largely had an effect on mitochondrial efficiency and excess complex IV capacity, but there were little differences in OXPHOS respiration and electron transfer capacity, pointing to a lack of significant differences in the metabolic capacity between juveniles and adults. Overall, these results demonstrate species-specific differences in cardiac metabolic capacity, which may influence the acclimation potential of notothenioid fishes to changing environmental conditions.
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Addressing the Neuroprotective Actions of Coffee in Parkinson’s Disease: An Emerging Nutrigenomic Analysis. Antioxidants (Basel) 2022; 11:antiox11081587. [PMID: 36009304 PMCID: PMC9405141 DOI: 10.3390/antiox11081587] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 08/08/2022] [Accepted: 08/10/2022] [Indexed: 11/17/2022] Open
Abstract
Caffeine is one of the predominant dietary components and psychostimulants present in coffee, a widely appreciated beverage. Corroborating epidemiological and laboratory evidence have suggested an inverse association between the dietary intakes of coffee and the risk of Parkinson’s Disease (PD). Growing attention has been paid to the impact of coffee consumption and genetic susceptibility to PD pathogenesis. Coffee is believed to play prominent roles in mediating the gene makeup and influencing the onset and progression of PD. The current review documents a current discovery of the coffee × gene interaction for the protective management of PD. The evidence underlying its potent impacts on the adenosine receptors (A2AR), estrogen receptors (ESR), heme oxygenase (HO), toxicant responsive genes, nitric oxide synthase (NOS), cytochrome oxidase (Cox), familial parkinsonism genetic susceptibility loci, bone marrow stromal cell antigen 1 (BST1), glutamate receptor gene and apolipoprotein E (APOE) genotype expressions is outlined. Furthermore, the neuroprotective mechanisms of coffee for the amelioration of PD are elucidated.
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10
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Di Trani JM, Moe A, Riepl D, Saura P, Kaila VRI, Brzezinski P, Rubinstein JL. Structural basis of mammalian complex IV inhibition by steroids. Proc Natl Acad Sci U S A 2022; 119:e2205228119. [PMID: 35858451 PMCID: PMC9335260 DOI: 10.1073/pnas.2205228119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 06/18/2022] [Indexed: 01/21/2023] Open
Abstract
The mitochondrial electron transport chain maintains the proton motive force that powers adenosine triphosphate (ATP) synthesis. The energy for this process comes from oxidation of reduced nicotinamide adenine dinucleotide (NADH) and succinate, with the electrons from this oxidation passed via intermediate carriers to oxygen. Complex IV (CIV), the terminal oxidase, transfers electrons from the intermediate electron carrier cytochrome c to oxygen, contributing to the proton motive force in the process. Within CIV, protons move through the K and D pathways during turnover. The former is responsible for transferring two protons to the enzyme's catalytic site upon its reduction, where they eventually combine with oxygen and electrons to form water. CIV is the main site for respiratory regulation, and although previous studies showed that steroid binding can regulate CIV activity, little is known about how this regulation occurs. Here, we characterize the interaction between CIV and steroids using a combination of kinetic experiments, structure determination, and molecular simulations. We show that molecules with a sterol moiety, such as glyco-diosgenin and cholesteryl hemisuccinate, reversibly inhibit CIV. Flash photolysis experiments probing the rapid equilibration of electrons within CIV demonstrate that binding of these molecules inhibits proton uptake through the K pathway. Single particle cryogenic electron microscopy (cryo-EM) of CIV with glyco-diosgenin reveals a previously undescribed steroid binding site adjacent to the K pathway, and molecular simulations suggest that the steroid binding modulates the conformational dynamics of key residues and proton transfer kinetics within this pathway. The binding pose of the sterol group sheds light on possible structural gating mechanisms in the CIV catalytic cycle.
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Affiliation(s)
- Justin M. Di Trani
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, ON, Canada M5G 0A4
| | - Agnes Moe
- Department of Biochemistry and Biophysics, Arrhenius Laboratories for Natural Sciences, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Daniel Riepl
- Department of Biochemistry and Biophysics, Arrhenius Laboratories for Natural Sciences, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Patricia Saura
- Department of Biochemistry and Biophysics, Arrhenius Laboratories for Natural Sciences, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Ville R. I. Kaila
- Department of Biochemistry and Biophysics, Arrhenius Laboratories for Natural Sciences, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Peter Brzezinski
- Department of Biochemistry and Biophysics, Arrhenius Laboratories for Natural Sciences, Stockholm University, SE-106 91 Stockholm, Sweden
| | - John L. Rubinstein
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, ON, Canada M5G 0A4
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada M5G 1L7
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada M5S 1A8
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11
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Huang HH, Stillman TJ, Branham LA, Williams SC. The Effects of Photobiomodulation Therapy on Porcine Islet Insulin Secretion. Photobiomodul Photomed Laser Surg 2022; 40:395-401. [DOI: 10.1089/photob.2022.0022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Han-Hung Huang
- Department of Physical Therapy, Angelo State University, Member, Texas Tech University System, San Angelo, Texas, USA
| | - Tori J. Stillman
- Department of Agriculture, and Angelo State University, Member, Texas Tech University System, San Angelo, Texas, USA
| | - Loree A. Branham
- Department of Agriculture, and Angelo State University, Member, Texas Tech University System, San Angelo, Texas, USA
| | - Scott C. Williams
- Department of Physics and Geosciences, Angelo State University, Member, Texas Tech University System, San Angelo, Texas, USA
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12
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Aharon-Hananel G, Romero-Afrima L, Saada A, Mantzur C, Raz I, Weksler-Zangen S. Cytochrome c Oxidase Activity as a Metabolic Regulator in Pancreatic Beta-Cells. Cells 2022; 11:cells11060929. [PMID: 35326380 PMCID: PMC8946064 DOI: 10.3390/cells11060929] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 03/01/2022] [Accepted: 03/03/2022] [Indexed: 02/06/2023] Open
Abstract
Pancreatic β-cells couple glucose-stimulated insulin secretion (GSIS) with oxidative phosphorylation via cytochrome c oxidase (COX), a mitochondrial respiratory-chain enzyme. The Cohen diabetic-sensitive (CDs) rats exhibit hyperglycemia when fed a diabetogenic diet but maintain normoglycemia on a regular diet. We have previously reported a decreased COX activity in CDs rats and explored its relevance for type 2 diabetes (T2D). In this study, we investigated the relation between COX activity in islets, peripheral-blood mononuclear cells (PBMCs), and GSIS during diabetes development in CDs rats fed a diabetogenic diet for 4, 11, 20, and 30 days and during reversion to normoglycemia in hyperglycemic CDs rats fed a reversion diet for 7, 11, and 20 days. An oral glucose-tolerance test was performed at different periods of the diets measuring blood glucose and insulin concentrations. COX activity was determined in islets and PBMCs isolated from rats at the different periods of the diets. We demonstrated a progressive reduction in COX activity in CDs-islets that correlated positively with the decreasing GSIS (R2 = 0.9691, p < 0.001) and inversely with the elevation in blood glucose levels (R2 = 0.8396, p < 0.001). Hyperglycemia was initiated when islet COX activity decreased below 46%. The reversion diet restored >46% of the islet COX activity and GSIS while re-establishing normoglycemia. Interestingly, COX activity in PBMCs correlated significantly with islet COX activity (R2 = 0.8944, p < 0.001). Our data support islet COX activity as a major metabolic regulator of β-cells function. The correlation between COX activity in PBMCs and islets may serve as a noninvasive biomarker to monitor β-cell dysfunction in diabetes.
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Affiliation(s)
- Genya Aharon-Hananel
- The Hadassah Diabetes Center, Hadassah Medical Center, Jerusalem 9112102, Israel; (G.A.-H.); (L.R.-A.); (C.M.); (I.R.)
- Division of Endocrinology, Diabetes and Metabolism, The Chaim Sheba Medical Center, Tel Hashomer, Ramat-Gan 5266202, Israel
- Sackler School of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
- The Department of Genetics, Hadassah Medical Center, Jerusalem 9112102, Israel;
| | - Leonor Romero-Afrima
- The Hadassah Diabetes Center, Hadassah Medical Center, Jerusalem 9112102, Israel; (G.A.-H.); (L.R.-A.); (C.M.); (I.R.)
- The Department of Genetics, Hadassah Medical Center, Jerusalem 9112102, Israel;
| | - Ann Saada
- The Department of Genetics, Hadassah Medical Center, Jerusalem 9112102, Israel;
- Faculty of Medicine Hebrew, University of Jerusalem, Jerusalem 9112102, Israel
| | - Carmit Mantzur
- The Hadassah Diabetes Center, Hadassah Medical Center, Jerusalem 9112102, Israel; (G.A.-H.); (L.R.-A.); (C.M.); (I.R.)
| | - Itamar Raz
- The Hadassah Diabetes Center, Hadassah Medical Center, Jerusalem 9112102, Israel; (G.A.-H.); (L.R.-A.); (C.M.); (I.R.)
- Faculty of Medicine Hebrew, University of Jerusalem, Jerusalem 9112102, Israel
| | - Sarah Weksler-Zangen
- The Hadassah Diabetes Center, Hadassah Medical Center, Jerusalem 9112102, Israel; (G.A.-H.); (L.R.-A.); (C.M.); (I.R.)
- Faculty of Medicine Hebrew, University of Jerusalem, Jerusalem 9112102, Israel
- The Liver Research Laboratory, Hadassah Medical Center, Jerusalem 9112102, Israel
- Correspondence: ; Tel.: +972-50-5172008
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13
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Xiao J, Luo SS, Du JH, Liu QY, Huang Y, Wang WF, Chen XL, Chen XH, Liu H, Zhou XY, Zhao YZ, Wang HL. Transcriptomic analysis of gills in nitrite-tolerant and -sensitive families of Litopenaeus vannamei. Comp Biochem Physiol C Toxicol Pharmacol 2022; 253:109212. [PMID: 34748971 DOI: 10.1016/j.cbpc.2021.109212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 09/21/2021] [Accepted: 10/06/2021] [Indexed: 11/16/2022]
Abstract
Nitrite stress is a major environmental factor that limits aquatic animal growth, reproduction and survival. Even so, some shrimps still can withstand somewhat high concentrations of nitrite environment. However, few studies have been conducted about the tolerance molecular mechanism of Litopenaeus vannamei in the high concentration nitrite. To identify the genes and pathways involved in the regulation of nitrite tolerance, we performed comparative transcriptomic analysis in the L. vannamei nitrite-tolerant (NT) and nitrite-sensitive (NS) families, and untreated shrimps were used as the control group. After 24 h of nitrite exposure (NaNO2, 112.5 mg/L), a total of 1521 and 868 differentially expressed genes (DEGs) were obtained from NT compared with NS and control group, respectively. Functional enrichment analysis revealed that most of these DEGs were involved in immune defense, energy metabolism processes and endoplasmic reticulum (ER) stress. During nitrite stress, energy metabolism in NT was significantly enhanced by activating the related genes expression of oxidative phosphorylation (OXPHOS) pathway and tricarboxylic acid (TCA) cycle. Meanwhile, some DEGs involved in innate immunity- related genes and pathways, and ER stress responses also were highly expressed in NT. Therefore, we speculate that accelerated energy metabolism, higher expression of immunity and ER related genes might be the important adaptive strategies for NT in relative to NS under nitrite stress. These results will provide new insights on the potential tolerant molecular mechanisms and the breeding of new varieties of nitrite tolerant L. vannamei.
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Affiliation(s)
- Jie Xiao
- key Lab of Freshwater Animal Breeding, Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Fishery Huazhong Agricultural University, Wuhan 430070, China
| | - Shuang-Shuang Luo
- key Lab of Freshwater Animal Breeding, Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Fishery Huazhong Agricultural University, Wuhan 430070, China
| | - Jing-Hao Du
- key Lab of Freshwater Animal Breeding, Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Fishery Huazhong Agricultural University, Wuhan 430070, China
| | - Qing-Yun Liu
- Guangxi Academy of Fishery Sciences, Guangxi Key Laboratory of Aquatic Genetic Breeding and Healthy Aquaculture, Nanning 530021, China
| | - Yan Huang
- key Lab of Freshwater Animal Breeding, Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Fishery Huazhong Agricultural University, Wuhan 430070, China
| | - Wei-Feng Wang
- key Lab of Freshwater Animal Breeding, Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Fishery Huazhong Agricultural University, Wuhan 430070, China
| | - Xiu-Li Chen
- Guangxi Academy of Fishery Sciences, Guangxi Key Laboratory of Aquatic Genetic Breeding and Healthy Aquaculture, Nanning 530021, China
| | - Xiao-Han Chen
- Guangxi Academy of Fishery Sciences, Guangxi Key Laboratory of Aquatic Genetic Breeding and Healthy Aquaculture, Nanning 530021, China
| | - Hong Liu
- key Lab of Freshwater Animal Breeding, Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Fishery Huazhong Agricultural University, Wuhan 430070, China
| | - Xiao-Yun Zhou
- key Lab of Freshwater Animal Breeding, Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Fishery Huazhong Agricultural University, Wuhan 430070, China
| | - Yong-Zhen Zhao
- Guangxi Academy of Fishery Sciences, Guangxi Key Laboratory of Aquatic Genetic Breeding and Healthy Aquaculture, Nanning 530021, China.
| | - Huan-Ling Wang
- key Lab of Freshwater Animal Breeding, Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Fishery Huazhong Agricultural University, Wuhan 430070, China.
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14
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Hevler JF, Zenezeni Chiozzi R, Cabrera-Orefice A, Brandt U, Arnold S, Heck AJR. Molecular characterization of a complex of apoptosis-inducing factor 1 with cytochrome c oxidase of the mitochondrial respiratory chain. Proc Natl Acad Sci U S A 2021; 118:e2106950118. [PMID: 34548399 PMCID: PMC8488679 DOI: 10.1073/pnas.2106950118] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/06/2021] [Indexed: 12/28/2022] Open
Abstract
Combining mass spectrometry-based chemical cross-linking and complexome profiling, we analyzed the interactome of heart mitochondria. We focused on complexes of oxidative phosphorylation and found that dimeric apoptosis-inducing factor 1 (AIFM1) forms a defined complex with ∼10% of monomeric cytochrome c oxidase (COX) but hardly interacts with respiratory chain supercomplexes. Multiple AIFM1 intercross-links engaging six different COX subunits provided structural restraints to build a detailed atomic model of the COX-AIFM12 complex (PDBDEV_00000092). An application of two complementary proteomic approaches thus provided unexpected insight into the macromolecular organization of the mitochondrial complexome. Our structural model excludes direct electron transfer between AIFM1 and COX. Notably, however, the binding site of cytochrome c remains accessible, allowing formation of a ternary complex. The discovery of the previously overlooked COX-AIFM12 complex and clues provided by the structural model hint at potential roles of AIFM1 in oxidative phosphorylation biogenesis and in programmed cell death.
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Affiliation(s)
- Johannes F Hevler
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research, Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, 3584 CH Utrecht, The Netherlands
- Netherlands Proteomics Center, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, 3584 CH Utrecht, The Netherlands
| | - Riccardo Zenezeni Chiozzi
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research, Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, 3584 CH Utrecht, The Netherlands
- Netherlands Proteomics Center, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, 3584 CH Utrecht, The Netherlands
| | - Alfredo Cabrera-Orefice
- Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Ulrich Brandt
- Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, University of Cologne, 50931 Cologne, Germany
| | - Susanne Arnold
- Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands;
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, University of Cologne, 50931 Cologne, Germany
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research, Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, 3584 CH Utrecht, The Netherlands;
- Netherlands Proteomics Center, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, 3584 CH Utrecht, The Netherlands
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15
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Rodríguez E, Hakkou M, Hagen TM, Lemieux H, Blier PU. Divergences in the Control of Mitochondrial Respiration Are Associated With Life-Span Variation in Marine Bivalves. J Gerontol A Biol Sci Med Sci 2021; 76:796-804. [PMID: 33257932 DOI: 10.1093/gerona/glaa301] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Indexed: 12/31/2022] Open
Abstract
The role played by mitochondrial function in the aging process has been a subject of intense debate in the past few decades, as part of the efforts to understand the mechanistic basis of longevity. The mitochondrial oxidative stress theory of aging suggests that a progressive decay of this organelle's function leads to an exacerbation of oxidative stress, with a deleterious impact on mitochondrial structure and DNA, ultimately promoting aging. Among the traits suspected to be associated with longevity is the variation in the regulation of oxidative phosphorylation, potentially affecting the management of oxidative stress. Longitudinal studies using the framework of metabolic control analysis have shown age-related differences in the flux control of respiration, but this approach has seldom been taken on a comparative scale. Using 4 species of marine bivalves exhibiting a large range of maximum life span (from 28 years to 507 years), we report life-span-related differences in flux control at different steps of the electron transfer system. Increased longevity was characterized by a lower control by NADH (complex I-linked) and Succinate (complex II-linked) pathways, while respiration was strongly controlled by complex IV when compared to shorter-lived species. Complex III exerted strong control over respiration in all species. Furthermore, high longevity was associated with higher citrate synthase activity and lower ATP synthase activity. Relieving the control exerted by the electron entry pathways could be advantageous for reaching higher longevity, leading to increased control by complex IV, the final electron acceptor in the electron transfer system.
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Affiliation(s)
- Enrique Rodríguez
- Département de Biologie, Université du Québec, Rimouski, Québec, Canada
| | - Mohammed Hakkou
- Département de Biologie, Université du Québec, Rimouski, Québec, Canada
| | - Tory M Hagen
- Linus Pauling Institute, Oregon State University, Corvallis, Oregon, USA
| | - Hélène Lemieux
- Faculty Saint-Jean, Department of Medicine, Women and Children Health Research Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Pierre U Blier
- Département de Biologie, Université du Québec, Rimouski, Québec, Canada
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16
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Brzezinski P, Moe A, Ädelroth P. Structure and Mechanism of Respiratory III-IV Supercomplexes in Bioenergetic Membranes. Chem Rev 2021; 121:9644-9673. [PMID: 34184881 PMCID: PMC8361435 DOI: 10.1021/acs.chemrev.1c00140] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Indexed: 12/12/2022]
Abstract
In the final steps of energy conservation in aerobic organisms, free energy from electron transfer through the respiratory chain is transduced into a proton electrochemical gradient across a membrane. In mitochondria and many bacteria, reduction of the dioxygen electron acceptor is catalyzed by cytochrome c oxidase (complex IV), which receives electrons from cytochrome bc1 (complex III), via membrane-bound or water-soluble cytochrome c. These complexes function independently, but in many organisms they associate to form supercomplexes. Here, we review the structural features and the functional significance of the nonobligate III2IV1/2 Saccharomyces cerevisiae mitochondrial supercomplex as well as the obligate III2IV2 supercomplex from actinobacteria. The analysis is centered around the Q-cycle of complex III, proton uptake by CytcO, as well as mechanistic and structural solutions to the electronic link between complexes III and IV.
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Affiliation(s)
- Peter Brzezinski
- Department of Biochemistry and Biophysics,
The Arrhenius Laboratories for Natural Sciences, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Agnes Moe
- Department of Biochemistry and Biophysics,
The Arrhenius Laboratories for Natural Sciences, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Pia Ädelroth
- Department of Biochemistry and Biophysics,
The Arrhenius Laboratories for Natural Sciences, Stockholm University, SE-106 91 Stockholm, Sweden
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17
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Guo L. Mitochondria and the permeability transition pore in cancer metabolic reprogramming. Biochem Pharmacol 2021; 188:114537. [PMID: 33811907 DOI: 10.1016/j.bcp.2021.114537] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 03/24/2021] [Accepted: 03/25/2021] [Indexed: 02/07/2023]
Abstract
Mitochondria are a major source of ATP provision as well as cellular suicidal weapon store. Accumulating evidences demonstrate that mitochondrial bioenergetics, biosynthesis and signaling are important mediators of tumorigenesis. Metabolic plasticity enables cancer cell reprogramming to cope with cellular and environmental alterations, a process requires mitochondria biology. Mitochondrial metabolism emerges to be a promising arena for cancer therapeutic targets. The permeability transition pore (PTP) participates in physiological Ca2+ and ROS homeostasis as well as cell death depending on the open state. The hypothesis that PTP forms from F-ATP synthase provides clues to the potential collaborative role of mitochondrial respiration and PTP in regulating cancer cell fate and metabolic reprogramming.
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Affiliation(s)
- Lishu Guo
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai 200072, China.
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18
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Zhang M, Zhang D, Ren J, Pu S, Wu H, Ma Z. Target verification of allyl isothiocyanate on the core subunits of cytochrome c oxidase in Sitophilus zeamais by RNAi. PEST MANAGEMENT SCIENCE 2021; 77:1292-1302. [PMID: 33063911 DOI: 10.1002/ps.6142] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 10/06/2020] [Accepted: 10/16/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Allyl isothiocyanate (AITC) is a volatile organic compound with a potent insecticidal activity to the stored-grain pest Sitophilus zeamais Motschulsky, which severely damages grain storage and container transport worldwide. Our previous study showed that mitochondrial complex IV was the primary target of AITC in adult Sitophilus zeamais. To further verify the targets of AITC, we employed RNA interference (RNAi) by using double-stranded RNA (dsRNA) to knockdown three core subunits of cytochrome c oxidase (COX)-I, -II and -III in 18-day-old larvae prior to their exposure to AITC to detect susceptibility changes. RESULTS The susceptibility of dsRNACOX-I and -II injection treatments to AITC significantly increased at 72 h while the mortality reached up to 85.56% and 67.78%, respectively, and dsRNACOX-I and dsRNACOX-II injection showed the same subcellular structural characteristics showing vacuolization and vague mitochondrial cristae and decrease of COX activity during AITC fumigation treatment, suggesting the potential of COX-I and COX-II as the targets of AITC. High mortality reached up to 75.55%, 71.88% and 82.22%, respectively, and the phenotype of larvae turning from milky white to dark brown in the thorax and death eventually was confirmed after dsRNACOX-I, -II and -III injection. CONCLUSION COX-I and -II were elucidated as the potential targets of AITC and dsRNACOX-I, -II and -III have the potential to be developed into nucleic acid pesticides for their robust lethal effects and are worth pursuing for improving AITC fumigation activity in Sitophilus zeamais control. © 2020 Society of Chemical Industry.
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Affiliation(s)
- Min Zhang
- College of Plant Protection, Northwest A&F University, Yangling, China
| | - Dan Zhang
- College of Plant Protection, Northwest A&F University, Yangling, China
| | - Jingjing Ren
- College of Plant Protection, Northwest A&F University, Yangling, China
| | - Shi Pu
- College of Plant Protection, Northwest A&F University, Yangling, China
| | - Hua Wu
- College of Plant Protection, Northwest A&F University, Yangling, China
- Shaanxi Research Center of Biopesticide Engineering and Technology, Northwest A&F University, Yangling, China
| | - Zhiqing Ma
- College of Plant Protection, Northwest A&F University, Yangling, China
- Shaanxi Research Center of Biopesticide Engineering and Technology, Northwest A&F University, Yangling, China
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19
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Upregulation of COX4-2 via HIF-1α in Mitochondrial COX4-1 Deficiency. Cells 2021; 10:cells10020452. [PMID: 33672589 PMCID: PMC7924049 DOI: 10.3390/cells10020452] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 02/17/2021] [Accepted: 02/18/2021] [Indexed: 01/08/2023] Open
Abstract
Cytochrome-c-oxidase (COX) subunit 4 (COX4) plays important roles in the function, assembly and regulation of COX (mitochondrial respiratory complex 4), the terminal electron acceptor of the oxidative phosphorylation (OXPHOS) system. The principal COX4 isoform, COX4-1, is expressed in all tissues, whereas COX4-2 is mainly expressed in the lungs, or under hypoxia and other stress conditions. We have previously described a patient with a COX4-1 defect with a relatively mild presentation compared to other primary COX deficiencies, and hypothesized that this could be the result of a compensatory upregulation of COX4-2. To this end, COX4-1 was downregulated by shRNAs in human foreskin fibroblasts (HFF) and compared to the patient’s cells. COX4-1, COX4-2 and HIF-1α were detected by immunocytochemistry. The mRNA transcripts of both COX4 isoforms and HIF-1 target genes were quantified by RT-qPCR. COX activity and OXPHOS function were measured by enzymatic and oxygen consumption assays, respectively. Pathways were analyzed by CEL-Seq2 and by RT-qPCR. We demonstrated elevated COX4-2 levels in the COX4-1-deficient cells, with a concomitant HIF-1α stabilization, nuclear localization and upregulation of the hypoxia and glycolysis pathways. We suggest that COX4-2 and HIF-1α are upregulated also in normoxia as a compensatory mechanism in COX4-1 deficiency.
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20
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Hill GE. Genetic hitchhiking, mitonuclear coadaptation, and the origins of mt DNA barcode gaps. Ecol Evol 2020; 10:9048-9059. [PMID: 32953045 PMCID: PMC7487244 DOI: 10.1002/ece3.6640] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 07/02/2020] [Accepted: 07/06/2020] [Indexed: 01/02/2023] Open
Abstract
DNA barcoding based on mitochondrial (mt) nucleotide sequences is an enigma. Neutral models of mt evolution predict DNA barcoding cannot work for recently diverged taxa, and yet, mt DNA barcoding accurately delimits species for many bilaterian animals. Meanwhile, mt DNA barcoding often fails for plants and fungi. I propose that because mt gene products must cofunction with nuclear gene products, the evolution of mt genomes is best understood with full consideration of the two environments that impose selective pressure on mt genes: the external environment and the internal genomic environment. Moreover, it is critical to fully consider the potential for adaptive evolution of not just protein products of mt genes but also of mt transfer RNAs and mt ribosomal RNAs. The tight linkage of genes on mt genomes that do not engage in recombination could facilitate selective sweeps whenever there is positive selection on any element in the mt genome, leading to the purging of mt genetic diversity within a population and to the rapid fixation of novel mt DNA sequences. Accordingly, the most important factor determining whether or not mt DNA sequences diagnose species boundaries may be the extent to which the mt chromosomes engage in recombination.
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21
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Wikström M, Springett R. Thermodynamic efficiency, reversibility, and degree of coupling in energy conservation by the mitochondrial respiratory chain. Commun Biol 2020; 3:451. [PMID: 32811895 PMCID: PMC7434914 DOI: 10.1038/s42003-020-01192-w] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 07/30/2020] [Indexed: 11/23/2022] Open
Abstract
The protonmotive mitochondrial respiratory chain, comprising complexes I, III and IV, transduces free energy of the electron transfer reactions to an electrochemical proton gradient across the inner mitochondrial membrane. This gradient is used to drive synthesis of ATP and ion and metabolite transport. The efficiency of energy conversion is of interest from a physiological point of view, since the energy transduction mechanisms differ fundamentally between the three complexes. Here, we have chosen actively phosphorylating mitochondria as the focus of analysis. For all three complexes we find that the thermodynamic efficiency is about 80–90% and that the degree of coupling between the redox and proton translocation reactions is very high during active ATP synthesis. However, when net ATP synthesis stops at a high ATP/ADP.Pi ratio, and mitochondria reach “State 4” with an elevated proton gradient, the degree of coupling drops substantially. The mechanistic cause and the physiological implications of this effect are discussed. Wikström and Springett analyze the thermodynamic efficiency of redox reactions and proton translocation by the complexes of mitochondrial respiratory chain. They report that the thermodynamic efficiency is about 80–90% and that the degree of coupling between the redox and proton translocation reactions is very high during active ATP synthesis, but decreases when ATP synthesis stops.
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Affiliation(s)
- Mårten Wikström
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland.
| | - Roger Springett
- Cardiovascular Division, King's College London, British Heart Foundation Centre of Excellence, 125 Coldharbour Lane, London, SE5 9NU, UK
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22
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Narayanan D, Ma S, Özcelik D. Targeting the Redox Landscape in Cancer Therapy. Cancers (Basel) 2020; 12:cancers12071706. [PMID: 32605023 PMCID: PMC7407119 DOI: 10.3390/cancers12071706] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 06/22/2020] [Accepted: 06/25/2020] [Indexed: 12/18/2022] Open
Abstract
Reactive oxygen species (ROS) are produced predominantly by the mitochondrial electron transport chain and by NADPH oxidases in peroxisomes and in the endoplasmic reticulum. The antioxidative defense counters overproduction of ROS with detoxifying enzymes and molecular scavengers, for instance, superoxide dismutase and glutathione, in order to restore redox homeostasis. Mutations in the redox landscape can induce carcinogenesis, whereas increased ROS production can perpetuate cancer development. Moreover, cancer cells can increase production of antioxidants, leading to resistance against chemo- or radiotherapy. Research has been developing pharmaceuticals to target the redox landscape in cancer. For instance, inhibition of key players in the redox landscape aims to modulate ROS production in order to prevent tumor development or to sensitize cancer cells in radiotherapy. Besides the redox landscape of a single cell, alternative strategies take aim at the multi-cellular level. Extracellular vesicles, such as exosomes, are crucial for the development of the hypoxic tumor microenvironment, and hence are explored as target and as drug delivery systems in cancer therapy. This review summarizes the current pharmaceutical and experimental interventions of the cancer redox landscape.
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Affiliation(s)
- Dilip Narayanan
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark; (D.N.); (S.M.)
| | - Sana Ma
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark; (D.N.); (S.M.)
| | - Dennis Özcelik
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark; (D.N.); (S.M.)
- current address: Chemistry | Biology | Pharmacy Information Center, ETH Zürich, Vladimir-Prelog-Weg 10, 8093 Zürich, Switzerland
- Correspondence:
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23
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Hartley AM, Meunier B, Pinotsis N, Maréchal A. Rcf2 revealed in cryo-EM structures of hypoxic isoforms of mature mitochondrial III-IV supercomplexes. Proc Natl Acad Sci U S A 2020; 117:9329-9337. [PMID: 32291341 PMCID: PMC7196821 DOI: 10.1073/pnas.1920612117] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The organization of the mitochondrial electron transport chain proteins into supercomplexes (SCs) is now undisputed; however, their assembly process, or the role of differential expression isoforms, remain to be determined. In Saccharomyces cerevisiae, cytochrome c oxidase (CIV) forms SCs of varying stoichiometry with cytochrome bc1 (CIII). Recent studies have revealed, in normoxic growth conditions, an interface made exclusively by Cox5A, the only yeast respiratory protein that exists as one of two isoforms depending on oxygen levels. Here we present the cryo-EM structures of the III2-IV1 and III2-IV2 SCs containing the hypoxic isoform Cox5B solved at 3.4 and 2.8 Å, respectively. We show that the change of isoform does not affect SC formation or activity, and that SC stoichiometry is dictated by the level of CIII/CIV biosynthesis. Comparison of the CIV5B- and CIV5A-containing SC structures highlighted few differences, found mainly in the region of Cox5. Additional density was revealed in all SCs, independent of the CIV isoform, in a pocket formed by Cox1, Cox3, Cox12, and Cox13, away from the CIII-CIV interface. In the CIV5B-containing hypoxic SCs, this could be confidently assigned to the hypoxia-induced gene 1 (Hig1) type 2 protein Rcf2. With conserved residues in mammalian Hig1 proteins and Cox3/Cox12/Cox13 orthologs, we propose that Hig1 type 2 proteins are stoichiometric subunits of CIV, at least when within a III-IV SC.
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Affiliation(s)
- Andrew M Hartley
- Institute of Structural and Molecular Biology, Birkbeck College, WC1E 7HX London, United Kingdom
| | - Brigitte Meunier
- Institute for Integrative Biology of the Cell (I2BC), CNRS, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Université Paris-Saclay, 91198 Gif-sur-Yvette, France
| | - Nikos Pinotsis
- Institute of Structural and Molecular Biology, Birkbeck College, WC1E 7HX London, United Kingdom
| | - Amandine Maréchal
- Institute of Structural and Molecular Biology, Birkbeck College, WC1E 7HX London, United Kingdom;
- Institute of Structural and Molecular Biology, University College London, WC1E 6BT London, United Kingdom
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24
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RIPC provides neuroprotection against ischemic stroke by suppressing apoptosis via the mitochondrial pathway. Sci Rep 2020; 10:5361. [PMID: 32210331 PMCID: PMC7093414 DOI: 10.1038/s41598-020-62336-w] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 02/10/2020] [Indexed: 12/18/2022] Open
Abstract
Ischemic stroke is a common disease with high morbidity and mortality. Remote ischemic preconditioning (RIPC) can stimulate endogenous protection mechanisms by inducing ischemic tolerance to reduce subsequent damage caused by severe or fatal ischemia to non-ischemic organs. This study was designed to assess the therapeutic properties of RIPC in ischemic stroke and to elucidate their underlying mechanisms. Neurobehavioral function was evaluated with the modified neurological severity score (mNSS) test and gait analysis. PET/CT was used to detect the ischemic volume and level of glucose metabolism. The protein levels of cytochrome c oxidase-IV (COX-IV) and heat shock protein 60 (HSP60) were tested by Western blotting. TUNEL and immunofluorescence staining were used to analyze apoptosis and to observe the nuclear translocation and colocalization of apoptosis-inducing factor (AIF) and endonuclease G (EndoG) in apoptotic cells. Transmission electron microscopy (TEM) was used to detect mitochondrial-derived vesicle (MDV) production and to assess mitochondrial ultrastructure. The experimental results showed that RIPC exerted significant neuroprotective effects, as indicated by improvements in neurological dysfunction, reductions in ischemic volume, increases in glucose metabolism, inhibition of apoptosis, decreased nuclear translocation of AIF and EndoG from mitochondria and improved MDV formation. In conclusion, RIPC alleviates ischemia/reperfusion injury after ischemic stroke by inhibiting apoptosis via the endogenous mitochondrial pathway.
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Wolf A, Dragelj J, Wonneberg J, Stellmacher J, Balke J, Woelke AL, Hodoscek M, Knapp EW, Alexiev U. The redox-coupled proton-channel opening in cytochrome c oxidase. Chem Sci 2020. [DOI: 10.1039/c9sc06463j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The interplay of cytochrome c oxidase's cofactor electrostatics, long-range conformational changes, H-bond rearrangement, and water dynamics enables transient proton-channel activation.
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Affiliation(s)
- Alexander Wolf
- Physics Department
- Freie Universität Berlin
- 14195 Berlin
- Germany
| | - Jovan Dragelj
- Institute of Chemistry and Biochemistry
- Freie Universität Berlin
- 14195 Berlin
- Germany
| | | | | | - Jens Balke
- Physics Department
- Freie Universität Berlin
- 14195 Berlin
- Germany
| | - Anna Lena Woelke
- Institute of Chemistry and Biochemistry
- Freie Universität Berlin
- 14195 Berlin
- Germany
- Department of Chemistry
| | - Milan Hodoscek
- Institute of Chemistry and Biochemistry
- Freie Universität Berlin
- 14195 Berlin
- Germany
- National Institute of Chemistry
| | - Ernst Walter Knapp
- Institute of Chemistry and Biochemistry
- Freie Universität Berlin
- 14195 Berlin
- Germany
| | - Ulrike Alexiev
- Physics Department
- Freie Universität Berlin
- 14195 Berlin
- Germany
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Borisov VB, Siletsky SA. Features of Organization and Mechanism of Catalysis of Two Families of Terminal Oxidases: Heme-Copper and bd-Type. BIOCHEMISTRY (MOSCOW) 2019; 84:1390-1402. [DOI: 10.1134/s0006297919110130] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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27
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Abou Anni IS, Zebral YD, Afonso SB, Moreno Abril SI, Lauer MM, Bianchini A. Life-time exposure to waterborne copper III: Effects on the energy metabolism of the killifish Poecilia vivipara. CHEMOSPHERE 2019; 227:580-588. [PMID: 31009864 DOI: 10.1016/j.chemosphere.2019.04.080] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Revised: 04/09/2019] [Accepted: 04/10/2019] [Indexed: 06/09/2023]
Abstract
Copper ions (Cu) are essential to life maintenance, nonetheless, elevated concentrations can be hazardous. Acute and sub-chronic toxic effects of this metal are well known and are usually related to enzymatic inhibition, elevated ROS production and dysfunction of energy metabolism. Despite that, chronic studies are extremely rare. Therefore, the aim of this study was to assess the effects of chronic exposure to 5, 9 and 20 μg/L Cu (28 ad 345 days) on the energy metabolism and survival of the killifish Poecilia vivipara. To accomplish that, we evaluated the activity of enzymes related to aerobic (pyruvate kinase (PK); citrate synthase (CS)) and anaerobic metabolism (lactate dehydrogenase (LDH)) in whole-body (28 days) or in gills, liver and muscle (345 days) of exposed fish. Additionally, whole-body oxygen consumption was evaluated in fish exposed for 28 days and hepatic and muscular expression of genes involved in mitochondrial metabolism (cox I, II and III and atp5a1) was assessed in animals exposed for 345 days. Finally, final survival was evaluated. Following 28 days, Cu did not affect survival neither enzyme activities. However, increased whole-body oxygen consumption was observed in comparison to control condition. After 345 days, 76.8%, 63.9%, 60.9% and 0% survival were observed for control, 5, 9 and 20 μg/L groups, respectively. Animals exposed to 5 and 9 μg/L had a significant reduction in branchial and muscular LDH activity and in hepatic PK activity. Also, exposure to 9 μg/L significantly increased hepatic CS activity. For gene expression, Cu down-regulated muscular cox II (9 μg/L) and III (5 and 9 μg/L), and up-regulated hepatic atp5a1 (9 μg/L). Findings reported in the present study indicate that chronic exposure to Cu induces tissue-specific responses in key aspects of the energetic metabolism. In gills and muscle, Cu leads to reduced energy production through inhibition of anaerobic pathways and mitochondrial respiratory chain. This effect is paralleled by an increased ATP consumption in the liver, characterized by the augmented CS activity and atp5a1 expression. Finally, reduced PK activity indicate that oxidative stress may be involved with the observed outcomes.
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Affiliation(s)
- Iuri Salim Abou Anni
- Programa de Pós-graduação Em Ciências Fisiológicas, Universidade Federal Do Rio Grande, Avenida Itália Km 8, Campus Carreiros, 96203-900, Rio Grande, RS, Brazil
| | - Yuri Dornelles Zebral
- Programa de Pós-graduação Em Ciências Fisiológicas, Universidade Federal Do Rio Grande, Avenida Itália Km 8, Campus Carreiros, 96203-900, Rio Grande, RS, Brazil
| | - Sidnei Braz Afonso
- Instituto de Ciências Biológicas, Universidade Federal Do Rio Grande, Avenida Itália Km 8, Campus Carreiros, 96203-900, Rio Grande, RS, Brazil
| | - Sandra Isabel Moreno Abril
- Programa de Pós-graduação Em Ciências Fisiológicas, Universidade Federal Do Rio Grande, Avenida Itália Km 8, Campus Carreiros, 96203-900, Rio Grande, RS, Brazil
| | - Mariana Machado Lauer
- Instituto de Ciências Biológicas, Universidade Federal Do Rio Grande, Avenida Itália Km 8, Campus Carreiros, 96203-900, Rio Grande, RS, Brazil
| | - Adalto Bianchini
- Programa de Pós-graduação Em Ciências Fisiológicas, Universidade Federal Do Rio Grande, Avenida Itália Km 8, Campus Carreiros, 96203-900, Rio Grande, RS, Brazil; Instituto de Ciências Biológicas, Universidade Federal Do Rio Grande, Avenida Itália Km 8, Campus Carreiros, 96203-900, Rio Grande, RS, Brazil.
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Effects of hypoxia-reoxygenation stress on mitochondrial proteome and bioenergetics of the hypoxia-tolerant marine bivalve Crassostrea gigas. J Proteomics 2019; 194:99-111. [DOI: 10.1016/j.jprot.2018.12.009] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 12/03/2018] [Accepted: 12/10/2018] [Indexed: 12/21/2022]
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Vogt S, Irqsusi M, Naraghi H, Sattler A, Ruppert V, Weber P, Rhiel A, Ramzan R. Mitochondrial active and relaxed state respiration after heat shock mRNA response in the heart. J Therm Biol 2019; 80:106-112. [PMID: 30784473 DOI: 10.1016/j.jtherbio.2019.01.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 01/02/2019] [Accepted: 01/06/2019] [Indexed: 12/11/2022]
Abstract
Induction of Heat Shock Proteins results in cytoprotection. Beneficial effect results from transcription and translational cellular components' involvement that defends metabolism and thus induce ischemic protection of the tissue. Mitochondrial respiration is also involved in stress- induced conditions. It is not a uniform process. Cytochrome c Oxidase (CytOx) representing complex IV of the Electron Transfer Chain (ETC) has a regulatory role for mitochondrial respiratory activity, which is tested in our study after hsp induction. Moreover, protein translation for mitochondrial components was probed by the detection of MT-CO1 for Subunit 1 of CytOx neosynthesis. Wistar rats were subjected to whole-body hyperthermia at 42.0-42.5 °C for 15 min followed by a normothermic recovery period. Heat shock response was monitored time dependent from LV biopsies of all control and heat treated animals with PCR-analysis for hsp 32, 60, 70.1, 70.2, 90 and MT-CO1 expression at 15, 30, 45, 60, 120 and 360 min recovery (n = 5 in each group), respectively. Enzymatic activity of CytOx were evaluated polarographically. High energy phosphates were detected by chromatographic analysis. The mRNA expression of MT-CO1 peaked at 60 min and was accompanied by hsp 32 (r = 0.457; p = 0.037) and hsp 70.2 (r = 0.615; p = 0.003) upregulation. With hsp induction, mitochondrial respiration was increased initially. Enzymatic activity reconciled from active into relaxed status wherein CytOx activity was completely inhibited by ATP. Myocardial ATP content increased from stress induced point i.e. < 1 µmol g-1 protein w/w to finally 1.5 ± 0.53 µmol g-1 protein w/w at 120 min recovery interval. Hyperthermic, myocardial hsp- induction goes along with increased CytOx activity representing an increased "active" mitochondrial respiration. In parallel, de -novo holoenzyme assembly of CytOx begins as shown by MT-CO1 upregulation at 60 min recovery time crossing with a final return to the physiological "relaxed" state and ATP -inhibited respiration.
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Affiliation(s)
- Sebastian Vogt
- Cardiovascular Surgery, Universitätsklinikum Marburg und Giessen GmbH, Germany; Cardiovascular Research Lab, Biochemical Pharmacological Center, Philipps, University Marburg, Germany.
| | - Marc Irqsusi
- Cardiovascular Surgery, Universitätsklinikum Marburg und Giessen GmbH, Germany
| | - Hamid Naraghi
- Cardiovascular Surgery, Universitätsklinikum Marburg und Giessen GmbH, Germany
| | - Alexander Sattler
- Center for Internal Medicine, Cardiology, Universitätsklinikum Marburg und Giessen GmbH, Germany
| | - Volker Ruppert
- Center for Internal Medicine, Cardiology, Universitätsklinikum Marburg und Giessen GmbH, Germany
| | - Petra Weber
- Cardiovascular Surgery, Universitätsklinikum Marburg und Giessen GmbH, Germany; Cardiovascular Research Lab, Biochemical Pharmacological Center, Philipps, University Marburg, Germany
| | - Annika Rhiel
- Cardiovascular Surgery, Universitätsklinikum Marburg und Giessen GmbH, Germany; Cardiovascular Research Lab, Biochemical Pharmacological Center, Philipps, University Marburg, Germany
| | - Rabia Ramzan
- Cardiovascular Surgery, Universitätsklinikum Marburg und Giessen GmbH, Germany; Cardiovascular Research Lab, Biochemical Pharmacological Center, Philipps, University Marburg, Germany
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Kaur H, Singh P. Rationally designed molecules for resurgence of cyanide mitigated cytochrome c oxidase activity. Bioorg Chem 2018; 82:229-240. [PMID: 30391853 DOI: 10.1016/j.bioorg.2018.10.045] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Revised: 10/19/2018] [Accepted: 10/22/2018] [Indexed: 11/26/2022]
Abstract
Cytochrome c oxidase (CcOX) containing binuclear heme a3-Cu B centre (BNC) mechanises the process of electron transfer in the last phase of cellular respiration. The molecular modelling based structural analysis of CcOX - heme a3-Cu B complex was performed and the disturbance to this complex under cyanide poisoning conditions was investigated. Taking into consideration the results of molecular docking studies, new chemical entities were developed for clipping cyanide from the enzyme and restoring its normal function. It was found that the molecules obtained by combining syringaldehyde, oxindole and chrysin moieties bearing propyl/butyl spacing groups occupy the BNC region and effectively remove cyanide bound to the enzyme. The binding constant of compound 2 with CN- was 2.3 × 105 M-1 and its ED50 for restoring the cyanide bound CcOX activity in 10 min was 16 µM. The compound interacted with CN- over the pH range 5-10. The comparison of the loss of enzymatic activity in the presence of CN- and resumption of enzymatic activity by compound 2 mediated removal of CN- indicated the efficacy of the compound as antidote of cyanide.
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Affiliation(s)
- Harpreet Kaur
- Department of Chemistry, UGC Sponsored Centre for Advanced Studies, Guru Nanak Dev University, Amritsar 143005, India
| | - Palwinder Singh
- Department of Chemistry, UGC Sponsored Centre for Advanced Studies, Guru Nanak Dev University, Amritsar 143005, India.
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Vogt S, Ruppert V, Pankuweit S, Paletta JPJ, Rhiel A, Weber P, Irqsusi M, Cybulski P, Ramzan R. Myocardial insufficiency is related to reduced subunit 4 content of cytochrome c oxidase. J Cardiothorac Surg 2018; 13:95. [PMID: 30223867 PMCID: PMC6142347 DOI: 10.1186/s13019-018-0785-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 09/11/2018] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Treatment of heart failure remains one of the most challenging task for intensive care medicine, cardiology and cardiac surgery. New options and better indicators are always required. Understanding the basic mechanisms underlying heart failure promote the development of adjusted therapy e.g. assist devices and monitoring of recovery. If cardiac failure is related to compromised cellular respiration of the heart, remains unclear. Myocardial respiration depends on Cytochrome c- Oxidase (CytOx) activity representing the rate limiting step for the mitochondrial respiratory chain. The enzymatic activity as well as mRNA expression of enzyme's mitochondrial encoded catalytic subunit 2, nuclear encoded regulatory subunit 4 and protein contents were studied in biopsies of cardiac patients suffering from myocardial insufficiency and dilated cardiomyopathy (DCM). METHODS Fifty-four patients were enrolled in the study and underwent coronary angiography. Thirty male patients (mean age: 45 +/- 15 yrs.) had a reduced ejection fraction (EF) 35 ± 12% below 45% and a left ventricular end diastolic diameter (LVEDD) of 71 ± 10 mm bigger than 56 mm. They were diagnosed as having idiopathic dilated cardiomyopathy (DCM) without coronary heart disease and NYHA-class 3 and 4. Additionally, 24 male patients (mean age: 52 +/- 11 yrs.) after exclusion of secondary cardiomyopathies, coronary artery or valve disease, served as control (EF: 68 ± 7, LVEDD: 51 ± 7 mm). Total RNA was extracted from two biopsies of each person. Real-time PCR analysis was performed with specific primers followed by a melt curve analysis. Corresponding protein expression in the tissue was studied with immune-histochemistry while enzymatic activity was evaluated by spectroscopy. RESULTS Gene and protein expression analysis of patients showed a significant decrease of subunit 4 (1.1 vs. 0.6, p < 0.001; 7.7 ± 3.1% vs. 2.8 ± 1.4%, p < 0.0001) but no differences in subunit 2. Correlations were found between reduced subunit 2 expression, low EF (r = 0.766, p < 0.00045) and increased LVEDD (r = 0.492, p < 0.0068). In case of DCM less subunit 4 expression and reduced shortening fraction (r = 0.524, p < 0.017) was found, but enzymatic activity was higher (0.08 ± 0.06 vs. 0.26 ± 0.08 U/mg, p < 0.001) although myocardial oxygen consumption continued to the same extent. CONCLUSION In case of myocardial insufficiency and DCM, decreased expression of COX 4 results in an impaired CytOx activity. Higher enzymatic activity but equal oxygen consumption contribute to the pathophysiology of the myocardial insufficiency and appears as an indicator of oxidative stress. This kind of dysregulation should be in the focus for the development of diagnostic and therapy procedures.
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Affiliation(s)
- Sebastian Vogt
- Cardiovascular Research Laboratories at the Biochemical Pharmacological Center, Philipps-University Marburg and Universitätsklinikum Gießen and Marburg GmbH, Marburg, Germany. .,Heart Surgery, Philipps-University Marburg and Universitätsklinikum Gießen and Marburg GmbH, Marburg, Germany.
| | - Volker Ruppert
- Department for Internal Medicine- Cardiology, Philipps-University Marburg and Universitätsklinikum Gießen and Marburg GmbH, Marburg, Germany
| | - Sabine Pankuweit
- Department for Internal Medicine- Cardiology, Philipps-University Marburg and Universitätsklinikum Gießen and Marburg GmbH, Marburg, Germany
| | - Jürgen P J Paletta
- Clinic for Orthopedics and Rheumatology, Philipps-University Marburg and Universitätsklinikum Gießen and Marburg GmbH, Marburg, Germany
| | - Annika Rhiel
- Cardiovascular Research Laboratories at the Biochemical Pharmacological Center, Philipps-University Marburg and Universitätsklinikum Gießen and Marburg GmbH, Marburg, Germany
| | - Petra Weber
- Cardiovascular Research Laboratories at the Biochemical Pharmacological Center, Philipps-University Marburg and Universitätsklinikum Gießen and Marburg GmbH, Marburg, Germany
| | - Marc Irqsusi
- Heart Surgery, Philipps-University Marburg and Universitätsklinikum Gießen and Marburg GmbH, Marburg, Germany
| | - Pia Cybulski
- Cardiovascular Research Laboratories at the Biochemical Pharmacological Center, Philipps-University Marburg and Universitätsklinikum Gießen and Marburg GmbH, Marburg, Germany
| | - Rabia Ramzan
- Cardiovascular Research Laboratories at the Biochemical Pharmacological Center, Philipps-University Marburg and Universitätsklinikum Gießen and Marburg GmbH, Marburg, Germany.,Heart Surgery, Philipps-University Marburg and Universitätsklinikum Gießen and Marburg GmbH, Marburg, Germany
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Wallace L, Cherian AM, Adamson P, Bari S, Banerjee S, Flood M, Simien M, Yao X, Aikhionbare FO. Comparison of Pre- and Post-translational Expressions of COXIV-1 and MT-ATPase 6 Genes in Colorectal Adenoma-Carcinoma Tissues. JOURNAL OF CARCINOGENESIS & MUTAGENESIS 2018; 9:319. [PMID: 30393577 PMCID: PMC6214464 DOI: 10.4172/2157-2518.1000319] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
OBJECTIVE Colorectal cancer (CRC) develops from precancerous adenomatous polyps to malignant lesions of adenocarcinoma. Elucidating inhibition mechanisms for this route in patients with a risk of developing CRC is highly important for a potential diagnostic or prognostic marker. Differential expression of nuclear-encoded cytochrome c oxidase subunit 4 (COXIV) seems to contribute to a more unregulated respiration due to loss of ATP inhibition. Majority of energy for tumor transformations are mitochondrial origin. Differences in mitochondrial efficiency may be reflected in the progression of colorectal adenomatous polyps to adenocarcinomas. Here, we evaluate expression levels of COXIV isoform 1 (COXIV-1) and Mitochondrial (MT)-ATP synthase Subunit 6 (ATPase6) in adenomas of tubular, tubulovillous and villous tissues as compared to adenocarcinoma tissues. METHOD Both RT-qPCR and western blot techniques were used to assess COXIV-1 and ATPase6 expression levels in 42 pairs of patients' tissue samples. Protein carbonyl assay was performed to determine levels of oxidized proteins, as a measurement of ROS productions, in the tissue samples. RESULTS Differential RNA expression levels of COXIV-1 and ATPase6 from whole tissues were observed. Interestingly, RNA expression levels obtained from mitochondrial for COXIV-1 were significantly decreased in tubulovillous, villous adenomas and adenocarcinoma, but not in the tubular-polyps. Moreover, mitochondrial ATPase6 RNA expression levels decreased progressively from adenopolyps to adenocarcinoma. In mitochondrial protein, expression levels of both genes progressively decreased with a three folds from adenomatous polyps to adenocarcinoma. Whilst the ATPase6 protein expression significantly decreased in adenocarcinoma compared to villous, conversely, the levels of oxidized carbonyl proteins were considerably increased from adenomatous polyps to adenocarcinoma. CONCLUSION Our findings provide evidence that decreased mitochondrial protein expression of COXIV-1 and ATPase6 correlates with increased ROS production during colorectal adenomatous polyps' progression, suggesting the pivotal role of COXIV-1 in energy metabolism of colorectal cells as they progress from polyps to carcinoma.
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Affiliation(s)
- LaShanale Wallace
- Department of Medicine, Morehouse School of Medicine, 720 Westview Dr. SW Atlanta, GA 30310-1495, USA
| | - Anju M Cherian
- Department of Medicine, Morehouse School of Medicine, 720 Westview Dr. SW Atlanta, GA 30310-1495, USA
| | - Paula Adamson
- Department of Medicine, Morehouse School of Medicine, 720 Westview Dr. SW Atlanta, GA 30310-1495, USA
| | - Shahla Bari
- Department of Medicine, Morehouse School of Medicine, 720 Westview Dr. SW Atlanta, GA 30310-1495, USA
| | - Saswati Banerjee
- Department of Medicine, Morehouse School of Medicine, 720 Westview Dr. SW Atlanta, GA 30310-1495, USA
| | - Michael Flood
- Department of Medicine, Morehouse School of Medicine, 720 Westview Dr. SW Atlanta, GA 30310-1495, USA
| | - Melvin Simien
- Department of Medicine, Morehouse School of Medicine, 720 Westview Dr. SW Atlanta, GA 30310-1495, USA
| | - Xuebiao Yao
- Department of Physiology, Morehouse School of Medicine, 720 Westview Dr. SW Atlanta, GA 30310-1495, USA
| | - Felix O Aikhionbare
- Department of Medicine, Morehouse School of Medicine, 720 Westview Dr. SW Atlanta, GA 30310-1495, USA
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Control of transmembrane charge transfer in cytochrome c oxidase by the membrane potential. Nat Commun 2018; 9:3187. [PMID: 30093670 PMCID: PMC6085328 DOI: 10.1038/s41467-018-05615-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 07/09/2018] [Indexed: 11/08/2022] Open
Abstract
The respiratory chain in mitochondria is composed of membrane-bound proteins that couple electron transfer to proton translocation across the inner membrane. These charge-transfer reactions are regulated by the proton electrochemical gradient that is generated and maintained by the transmembrane charge transfer. Here, we investigate this feedback mechanism in cytochrome c oxidase in intact inner mitochondrial membranes upon generation of an electrochemical potential by hydrolysis of ATP. The data indicate that a reaction step that involves proton uptake to the catalytic site and presumably proton translocation is impaired by the potential, but electron transfer is not affected. These results define the order of electron and proton-transfer reactions and suggest that the proton pump is regulated by the transmembrane electrochemical gradient through control of internal proton transfer rather than by control of electron transfer.
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Angers B, Chapdelaine V, Deremiens L, Vergilino R, Leung C, Doucet SL, Glémet H, Angers A. Gene flow prevents mitonuclear co-adaptation: A comparative portrait of sympatric wild types and cybrids in the fish Chrosomus eos. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2018; 27:77-84. [PMID: 29986214 DOI: 10.1016/j.cbd.2018.06.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 06/27/2018] [Accepted: 06/28/2018] [Indexed: 11/26/2022]
Abstract
Allospecific mtDNA can occasionally be beneficial for the fitness of populations. It is, however, difficult to assess the effect of mtDNA in natural conditions due to genetic and/or environmental interactions. In the fish Chrosomus eos, the transfer of C. neogaeus mitochondria occurs in a single generation and results in natural cybrids. For a few lakes in Quebec, C. eos can harbor either a C. eos mtDNA (wild types) or a C. neogaeus mtDNA (cybrids). Moreover, mtDNA of cybrids originated either from Mississippian or Atlantic glacial refuges. Such diversity provides a useful system for in situ assessment of allospecific mtDNA effects. We determined genetic, epigenetic and transcriptomic variation as well as mitochondrial enzymatic activity (complex IV) changes among wild types and cybrids either in sympatry or allopatry. Wild types and cybrids did not segregate spatially within a lake. Moreover, no significant genetic differentiation was detected among wild types and cybrids indicating sustained gene flow. Mitochondrial complex IV activity was higher for cybrids in both sympatry and allopatry while no difference was detected among cybrid haplotypes. Epigenetic and transcriptomic analyses revealed only subtle differences between sympatric wild types and cybrids compared to differences between sites. Altogether, these results indicate a limited influence of allospecific mtDNA in nuclear gene expression when controlling for genetic and environmental effects. The absence of a reproductive barrier between wild types and cybrids results in random association of either C. eos or C. neogaeus mtDNA with C. eos nDNA at each generation, and prevents mitonuclear co-adaptation in sympatry.
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Affiliation(s)
- Bernard Angers
- Department of biological sciences, Université de Montréal, C.P. 6128, Succ. Centre-Ville, Montréal, Québec H3C 3J7, Canada.
| | - Vincent Chapdelaine
- Department of biological sciences, Université de Montréal, C.P. 6128, Succ. Centre-Ville, Montréal, Québec H3C 3J7, Canada
| | - Léo Deremiens
- Department of biological sciences, Université de Montréal, C.P. 6128, Succ. Centre-Ville, Montréal, Québec H3C 3J7, Canada
| | - Roland Vergilino
- Department of biological sciences, Université de Montréal, C.P. 6128, Succ. Centre-Ville, Montréal, Québec H3C 3J7, Canada
| | - Christelle Leung
- Department of biological sciences, Université de Montréal, C.P. 6128, Succ. Centre-Ville, Montréal, Québec H3C 3J7, Canada
| | - Simon-Luc Doucet
- Department of biological sciences, Université de Montréal, C.P. 6128, Succ. Centre-Ville, Montréal, Québec H3C 3J7, Canada
| | - Hélène Glémet
- Department of environmental sciences, Université du Québec à Trois-Rivières, C.P. 500, Trois-Rivières, Québec G9A 5H7, Canada
| | - Annie Angers
- Department of biological sciences, Université de Montréal, C.P. 6128, Succ. Centre-Ville, Montréal, Québec H3C 3J7, Canada
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Hu YC, Chung MH, Lee TH. An assay of optimal cytochrome c oxidase activity in fish gills. Anal Biochem 2018; 553:38-45. [PMID: 29787731 DOI: 10.1016/j.ab.2018.05.017] [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] [Received: 11/07/2017] [Revised: 05/11/2018] [Accepted: 05/16/2018] [Indexed: 10/16/2022]
Abstract
Cytochrome c oxidase (COX) catalyzes the terminal oxidation reaction in the electron transport chain (ETC) of aerobic respiratory systems. COX activity is an important indicator for the evaluation of energy production by aerobic respiration in various tissues. On the basis of the respiratory characteristics of muscle, we established an optimal method for the measurement of maximal COX activity. To validate the measurement of cytochrome c absorbance, different ionic buffer concentrations and tissue homogenate protein concentrations were used to investigate COX activity. The results showed that optimal COX activity is achieved when using 50-100 μg fish gill homogenate in conjunction with 75-100 mM potassium phosphate buffer. Furthermore, we compared branchial COX activities among three species of euryhaline teleost (Chanos chanos, Oreochromis mossambicus, and Oryzias dancena) to investigate differences in aerobic respiration of osmoregulatory organs. COX activities in the gills of these three euryhaline species were compared with COX subunit 4 (COX4) protein levels. COX4 protein abundance and COX activity patterns in the three species occurring in environments with various salinities increased when fish encountered salinity challenges. This COX activity assay therefore provides an effective and accurate means of assessing aerobic metabolism in fish.
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Affiliation(s)
- Yau-Chung Hu
- Department of Life Sciences, National Chung Hsing University, Taichung, 402, Taiwan
| | - Meng-Han Chung
- Department of Life Sciences, National Chung Hsing University, Taichung, 402, Taiwan
| | - Tsung-Han Lee
- Department of Life Sciences, National Chung Hsing University, Taichung, 402, Taiwan; The iEGG and Animal Biotechnology Center, National Chung Hsing University, Taichung, 402, Taiwan.
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Sasaki K, Ono M, Takabe K, Suzuki A, Kurihara Y. Specific intron-dependent loading of DAZAP1 onto the cox6c transcript suppresses pre-mRNA splicing efficacy and induces cell growth retardation. Gene 2018; 657:1-8. [DOI: 10.1016/j.gene.2018.03.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 02/15/2018] [Accepted: 03/02/2018] [Indexed: 10/17/2022]
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Identification and characterization two isoforms of NADH:ubiquinone oxidoreductase from the hyperthermophilic eubacterium Aquifex aeolicus. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2018; 1859:366-373. [DOI: 10.1016/j.bbabio.2018.02.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 02/18/2018] [Accepted: 02/24/2018] [Indexed: 12/20/2022]
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Cortes PA, Bozinovic F, Blier PU. Mitochondrial phenotype during torpor: Modulation of mitochondrial electron transport system in the Chilean mouse-opossum Thylamys elegans. Comp Biochem Physiol A Mol Integr Physiol 2018; 221:7-14. [PMID: 29551753 DOI: 10.1016/j.cbpa.2017.12.014] [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] [Received: 09/13/2017] [Revised: 11/30/2017] [Accepted: 12/08/2017] [Indexed: 12/20/2022]
Abstract
Mammalian torpor is a phenotype characterized by a controlled decline of metabolic rate, generally followed by a reduction in body temperature. During arousal from torpor, both metabolic rate and body temperature rapidly returns to resting levels. Metabolic rate reduction experienced by torpid animals is triggered by active suppression of mitochondrial respiration, which is rapidly reversed during rewarming process. In this study, we analyzed the changes in the maximal activity of key enzymes related to electron transport system (complexes I, III and IV) in six tissues of torpid, arousing and euthermic Chilean mouse-opossums (Thylamys elegans). We observed higher maximal activities of complexes I and IV during torpor in brain, heart and liver, the most metabolically active organs in mammals. On the contrary, higher enzymatic activities of complexes III were observed during torpor in kidneys and lungs. Moreover, skeletal muscle was the only tissue without significant differences among stages in all complexes evaluated, suggesting no modulation of oxidative capacities of electron transport system components in this thermogenic tissue. In overall, our data suggest that complexes I and IV activity plays a major role in initiation and maintenance of metabolic suppression during torpor in Chilean mouse-opossum, whereas improvement of oxidative capacities in complex III might be critical to sustain metabolic machinery in organs that remains metabolically active during torpor.
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Affiliation(s)
- Pablo A Cortes
- Escuela de Agronomía, Facultad de Ciencias, Universidad Mayor, Camino La Pirámide, 5750, Huechuraba, Chile; Departamento de Ecología, Center of Applied Ecology and Sustainability, Facultad de Ciencias Biológicas, Universidad Católica de Chile, Santiago 6513677, Chile.
| | - Francisco Bozinovic
- Departamento de Ecología, Center of Applied Ecology and Sustainability, Facultad de Ciencias Biológicas, Universidad Católica de Chile, Santiago 6513677, Chile
| | - Pierre U Blier
- Département de Biologie, Laboratoire de Physiologie Animale Intégrative, Université du Québec, Rimouski G5L 3A1, QC, Canada
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de Oliveira MR, Brasil FB, Fürstenau CR. Evaluation of the Mitochondria-Related Redox and Bioenergetics Effects of Gastrodin in SH-SY5Y Cells Exposed to Hydrogen Peroxide. J Mol Neurosci 2018; 64:242-251. [PMID: 29330687 DOI: 10.1007/s12031-018-1027-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 01/03/2018] [Indexed: 12/18/2022]
Abstract
Mitochondrion is the main site of ATP production in animal cells and also orchestrates signaling pathways associated with cell survival and death. Mitochondrial dysfunction has been linked to bioenergetics and redox impairment in human diseases, such as neurodegeneration and cardiovascular disease. Protective agents able to attenuate mitochondrial impairment are of pharmacological interest. Gastrodin (GAS; 4-hydroxybenzyl alcohol 4-O-beta-D-glucoside) is a phenolic glucoside obtained from the Chinese herbal medicine Gastrodia elata Blume and exhibits antioxidant, anti-inflammatory, and antiapoptotic effects in several cell types. GAS is able to cross the blood-brain barrier, reducing the impact of different stressors on the cognition of experimental animals. In the present work, we investigated whether GAS would protect mitochondria of human SH-SY5Y neuroblastoma cells against an exposure to a pro-oxidant agent. The cells were treated with GAS at 25 μM for 30 min before the administration of hydrogen peroxide (H2O2) at 300 μM for an additional 3 or 24 h, depending on the assay. We evaluated both mitochondrial redox state and function parameters and analyzed the mechanism by which GAS protected mitochondria in this experimental model. Silencing of the nuclear factor erythroid 2-related factor 2 (Nrf2) transcription factor suppressed the GAS-induced mitochondrial protection seen here. Moreover, Nrf2 knockdown abrogated the effects of GAS on cell viability, indicating a potential role for Nrf2 in both mitochondrial and cellular protection promoted by GAS. Further research would be necessary to investigate whether GAS would be able to induce similar effects in in vivo experimental models.
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Affiliation(s)
- Marcos Roberto de Oliveira
- Department of Chemistry/ICET, Federal University of Mato Grosso (UFMT), Av. Fernando Corrêa da Costa, 2367, Cuiaba, MT, 78060-900, Brazil.
| | | | - Cristina Ribas Fürstenau
- Instituto de Genética e Bioquímica (INGEB), Universidade Federal de Uberlândia (UFU), Patos de Minas, MG, Brazil
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Jung KA, Lee S, Kwak MK. NFE2L2/NRF2 Activity Is Linked to Mitochondria and AMP-Activated Protein Kinase Signaling in Cancers Through miR-181c/Mitochondria-Encoded Cytochrome c Oxidase Regulation. Antioxid Redox Signal 2017; 27:945-961. [PMID: 28383996 DOI: 10.1089/ars.2016.6797] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
AIMS The nuclear factor (erythroid-derived 2)-like 2 (NFE2L2; NFE2L2/NRF2) pathway contributes to the environmental resistance of cancers by enhancing the antioxidant capacity. Here, we explored the potential connection between NFE2L2/NRF2 and mitochondrial function in cancers. RESULTS Global miRNA expression analysis of HT29 and HCT116 human colon cancer cells identified that NFE2L2/NRF2 silencing upregulated miR-181c through nuclear factor-κB signaling, and this increase was associated with the reduction in mitochondria-encoded cytochrome c oxidase subunit-1 (MT-CO1), a catalytic core subunit of the complex IV of the electron transport chain (ETC). As a result of ETC dysfunction, NFE2L2/NRF2-silenced cancer cells exhibited the decreases in the mitochondrial membrane potential, oxygen consumption rate, and cellular adenosine triphosphate (ATP) contents. Notably, these changes induced adenosine monophosphate (AMP)-activated protein kinase-α (AMPKα) activation and subsequent metabolic adaptation signaling, including the inhibition of fatty acid and sterol biosynthesis enzymes. As supportive evidence of AMPKα-driven adaption, NFE2L2/NRF2-silenced cells were more vulnerable to AMPKα inhibition-induced growth suppression. Similarly, mouse tumor xenografts derived from NFE2L2/NRF2-silenced HT29 exhibited MT-CO1 reduction and AMPKα activation, thereby increasing responsiveness to the AMPK inhibitor treatment. The association of NFE2L2/NRF2 with MT-CO1 and AMPKα was confirmed in breast cancer cells. INNOVATION We demonstrated the significance of NFE2L2/NRF2 in cancer mitochondria by elucidating the involvement of miR-181c/MT-CO1 as underlying molecular events. We also provide evidence of the crosstalk between NFE2L2/NRF2 and AMPKα as an adaptive link in cancers. CONCLUSION Therefore, it may be an effective strategy to inhibit both NFE2L2/NRF2 and AMPKα signaling to overcome adaptive behaviors of cancer. Antioxid. Redox Signal. 27, 945-961.
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Affiliation(s)
- Kyeong-Ah Jung
- 1 Department of Pharmacy, Graduate School of The Catholic University of Korea , Bucheon, Gyeonggi-do, Republic of Korea
| | - Sujin Lee
- 1 Department of Pharmacy, Graduate School of The Catholic University of Korea , Bucheon, Gyeonggi-do, Republic of Korea
| | - Mi-Kyoung Kwak
- 1 Department of Pharmacy, Graduate School of The Catholic University of Korea , Bucheon, Gyeonggi-do, Republic of Korea.,2 College of Pharmacy, The Catholic University of Korea , Bucheon, Gyeonggi-do, Republic of Korea
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Adzic M, Mitic M, Radojcic M. Mitochondrial estrogen receptors as a vulnerability factor of chronic stress and mediator of fluoxetine treatment in female and male rat hippocampus. Brain Res 2017; 1671:77-84. [DOI: 10.1016/j.brainres.2017.07.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 06/12/2017] [Accepted: 07/11/2017] [Indexed: 01/22/2023]
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de Oliveira MR, Brasil FB, Andrade CMB. Naringenin Attenuates H 2O 2-Induced Mitochondrial Dysfunction by an Nrf2-Dependent Mechanism in SH-SY5Y Cells. Neurochem Res 2017; 42:3341-3350. [PMID: 28786049 DOI: 10.1007/s11064-017-2376-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 07/19/2017] [Accepted: 08/03/2017] [Indexed: 02/07/2023]
Abstract
Mitochondria are the major site of ATP production in mammalian cells. Furthermore, these organelles are a source and a target of reactive oxygen species (ROS), such as radical anion superoxide (O2-·) and hydrogen peroxide (H2O2). The transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) is the master regulator of the mammalian redox biology and controls the expression of antioxidant and phase II detoxifying enzymes in several cell types. Naringenin (NGN, 5,7-dihydroxy-2-(4-hydroxyphenyl)-2,3-dihydrochromen-4-one), a flavanone, exhibits cytoprotective effects by acting as an antioxidant and anti-inflammatory agent. NGN is a potent activator of Nrf2. Nonetheless, it was not examine yet whether NGN would induce mitochondrial protection in cells under redox stress. Therefore, we investigate here whether Nrf2 would be involved in the mitochondrial protection elicited by NGN in SH-SY5Y cells exposed to H2O2. We observed that a pretreatment with NGN at 80 µM for 2 h reduced the levels of lipid peroxidation, protein carbonylation, and protein nitration in the membranes of mitochondria obtained from H2O2-treated SH-SY5Y cells. Additionally, NGN prevented the H2O2-induced impairment in the function of the enzymes aconitase, α-ketoglutarate dehydrogenase, and succinate dehydrogenase. The activites of the complexes I and V, as well as the production of ATP, were restored by NGN. NGN also suppressed the H2O2-induced mitochondria-related apoptosis. Interestingly, NGN promoted an increase in the levels of both total and mitochondrial glutathione (GSH). Silencing of Nrf2 abolished the protective effects induced by NGN. Overall, NGN induced mitochondrial protection by an Nrf2-dependent mechanism in H2O2-treated SH-SY5Y cells.
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Affiliation(s)
- Marcos Roberto de Oliveira
- Department of Chemistry/ICET, Federal University of Mato Grosso (UFMT), Av. Fernando Corrêa da Costa, 2367, Cuiaba, MT,, CEP 78060-900, Brazil.
| | | | - Cláudia Marlise Balbinotti Andrade
- Department of Chemistry/ICET, Federal University of Mato Grosso (UFMT), Av. Fernando Corrêa da Costa, 2367, Cuiaba, MT,, CEP 78060-900, Brazil
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Diabetes-induced abnormalities of mitochondrial function in rat brain cortex: the effect of n-3 fatty acid diet. Mol Cell Biochem 2017; 435:109-131. [DOI: 10.1007/s11010-017-3061-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Accepted: 05/04/2017] [Indexed: 01/07/2023]
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Salvador-Severo K, Gómez-Caudillo L, Quezada H, García-Trejo JDJ, Cárdenas-Conejo A, Vázquez-Memije ME, Minauro-Sanmiguel F. Mitochondrial proteomic profile of complex IV deficiency fibroblasts: rearrangement of oxidative phosphorylation complex/supercomplex and other metabolic pathways. BOLETIN MEDICO DEL HOSPITAL INFANTIL DE MEXICO 2017; 74:175-180. [DOI: 10.1016/j.bmhimx.2017.05.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 05/03/2017] [Accepted: 03/27/2017] [Indexed: 01/10/2023] Open
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Alexander-Shani R, Mreisat A, Smeir E, Gerstenblith G, Stern MD, Horowitz M. Long-term HIF-1α transcriptional activation is essential for heat-acclimation-mediated cross tolerance: mitochondrial target genes. Am J Physiol Regul Integr Comp Physiol 2017; 312:R753-R762. [PMID: 28274939 DOI: 10.1152/ajpregu.00461.2016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 03/01/2017] [Accepted: 03/03/2017] [Indexed: 11/22/2022]
Abstract
An important adaptive feature of heat acclimation (HA) is the induction of cross tolerance against novel stressors (HACT) Reprogramming of gene expression leading to enhanced innate cytoprotective features by attenuating damage and/or enhancing the response of "help" signals plays a pivotal role. Hypoxia-inducible factor-1α (HIF-1α), constitutively upregulated by HA (1 mo, 34°C), is a crucial transcription factor in this program, although its specific role is as yet unknown. By using a rat HA model, we studied the impact of disrupting HIF-1α transcriptional activation [HIF-1α:HIF-1β dimerization blockade by intraperitoneal acriflavine (4 mg/kg)] on its mitochondrial gene targets [phosphoinositide-dependent kinase-1 (PDK1), LON, and cyclooxygenase 4 (COX4) isoforms] in the HA rat heart. Physiological measures of cardiac HACT were infarct size after ischemia-reperfusion and time to rigor contracture during hypoxia in cardiomyocytes. We show that HACT requires transcriptional activation of HIF-1α throughout the course of HA and that this activation is accompanied by two metabolic switches: 1) profound upregulation of PDK1, which reduces pyruvate entry into the mitochondria, consequently increasing glycolytic lactate production; 2) remodeling of the COX4 isoform ratio, inducing hypoxic-tolerant COX4.2 dominance, and optimizing electron transfer and possibly ATP production during the ischemic and hypoxic insults. LON and COX4.2 transcript upregulation accompanied this shift. Loss of HACT despite elevated expression of the cytoprotective protein heat shock protein-72 concomitantly with disrupted HIF-1α dimerization suggests that HIF-1α is essential for HACT. The role of a PDK1 metabolic switch is well known in hypoxia acclimation but not in the HA model and its ischemic setting. Remodeling of COX4 isoforms by environmental acclimation is a novel finding.
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Affiliation(s)
- Rivka Alexander-Shani
- Laboratory of Environmental Physiology, Faculty of Dental Medicine, The Hebrew University, Jerusalem, Israel
| | - Ahmad Mreisat
- Laboratory of Environmental Physiology, Faculty of Dental Medicine, The Hebrew University, Jerusalem, Israel
| | - Elia Smeir
- Laboratory of Environmental Physiology, Faculty of Dental Medicine, The Hebrew University, Jerusalem, Israel
| | | | - Michael D Stern
- Gerontology Research Center, National Institute on Aging, Baltimore, Maryland
| | - Michal Horowitz
- Laboratory of Environmental Physiology, Faculty of Dental Medicine, The Hebrew University, Jerusalem, Israel;
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Pichaud N, Ekström A, Hellgren K, Sandblom E. Dynamic changes in cardiac mitochondrial metabolism during warm acclimation in rainbow trout. ACTA ACUST UNITED AC 2017; 220:1674-1683. [PMID: 28202582 DOI: 10.1242/jeb.152421] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Accepted: 02/13/2017] [Indexed: 01/06/2023]
Abstract
Although the mitochondrial metabolism responses to warm acclimation have been widely studied in fish, the time course of this process is less understood. Here, we characterized the changes of rainbow trout (Oncorhynchus mykiss) cardiac mitochondrial metabolism during acute warming from 10 to 16°C, and during the subsequent warm acclimation for 39 days. We repeatedly measured mitochondrial oxygen consumption in cardiac permeabilized fibers and the functional integrity of mitochondria (i.e. mitochondrial coupling and cytochrome c effect) at two assay temperatures (10 and 16°C), as well as the activities of citrate synthase (CS) and lactate dehydrogenase (LDH) at room temperature. LDH and CS activities significantly increased between day 0 (10°C acclimated fish) and day 1 (acute warming to 16°C) while mitochondrial oxygen consumption measured at respective in vivo temperatures did not change. Enzymatic activities and mitochondrial oxygen consumption rates significantly decreased by day 2, and remained stable during warm acclimation (days 2-39). The decrease in rates of oxygen between day 0 and day 1 coincided with an increased cytochrome c effect and a decreased mitochondrial coupling, suggesting a structural/functional impairment of mitochondria during acute warming. We suggest that after 2 days of warm acclimation, a new homeostasis is reached, which may involve the removal of dysfunctional mitochondria. Interestingly, from day 2 onwards, there was a lack of differences in mitochondrial oxygen consumption rates between the assay temperatures, suggesting that warm acclimation reduces the acute thermal sensitivity of mitochondria. This study provides significant knowledge on the thermal sensitivity of cardiac mitochondria that is essential to delineate the contribution of cellular processes to warm acclimation.
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Affiliation(s)
- Nicolas Pichaud
- Department of Chemistry and Biochemistry, University of Moncton, Moncton, New Brunswick, Canada E1A 3E9 .,Department of Biological and Environmental Sciences, University of Gothenburg, SE-405 30 Gothenburg, Sweden
| | - Andreas Ekström
- Department of Biological and Environmental Sciences, University of Gothenburg, SE-405 30 Gothenburg, Sweden
| | - Kim Hellgren
- Department of Biological and Environmental Sciences, University of Gothenburg, SE-405 30 Gothenburg, Sweden
| | - Erik Sandblom
- Department of Biological and Environmental Sciences, University of Gothenburg, SE-405 30 Gothenburg, Sweden
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Dos Santos APR, Rocha TL, Borges CL, Bailão AM, de Almeida Soares CM, de Sabóia-Morais SMT. A glyphosate-based herbicide induces histomorphological and protein expression changes in the liver of the female guppy Poecilia reticulata. CHEMOSPHERE 2017; 168:933-943. [PMID: 27836263 DOI: 10.1016/j.chemosphere.2016.10.116] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 10/26/2016] [Accepted: 10/27/2016] [Indexed: 06/06/2023]
Abstract
Glyphosate-based herbicides (GBH) are among the most common herbicides found in aquatic systems, but limited data are available about their mode of action and hepatotoxicity in fish. This study investigated the hepatotoxicity induced by GBH in the guppy Poecilia reticulata using a histopathological assessment associated with a proteomic approach. Guppies were exposed to GBH for 24 h at 1.8 mg of glyphosate L-1, corresponding to 50% of the LC50, 96 h. The results indicate that the GBH at 1.8 mg of glyphosate L-1 induce the development of hepatic damage in P. reticulata, which is exposure-time dependent. The histopathological indexes demonstrate that GBH cause inflammatory, regressive, vascular and progressive disorders in the liver of guppies. Using 2D gel electrophoresis associated with mass spectrometry, 18 proteins that changed by GBH were identified and were related to the cellular structure, motility and transport, energy metabolism and apoptosis. The results show that the acute exposure to GBH causes hepatic histopathological damage related to protein expression profile changes in P. reticulata, indicating that a histopathological assessment associated with a proteomic analysis provides a valuable approach to assess the toxic effects of GBH in sentinel fish species.
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Affiliation(s)
- Ana Paula Rezende Dos Santos
- Laboratory of Cellular Behavior, Biological Sciences Institute, Federal University of Goiás, Goiânia, Goiás, Brazil
| | - Thiago Lopes Rocha
- Laboratory of Cellular Behavior, Biological Sciences Institute, Federal University of Goiás, Goiânia, Goiás, Brazil; CIMA, Faculty of Science and Technology, University of Algarve, Campus de Gambelas, Faro, Portugal
| | - Clayton Luiz Borges
- Laboratory of Molecular Biology, Biological Sciences Institute, Federal University of Goiás, Goiânia, Goiás, Brazil
| | - Alexandre Melo Bailão
- Laboratory of Molecular Biology, Biological Sciences Institute, Federal University of Goiás, Goiânia, Goiás, Brazil
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Low Cytochrome Oxidase 1 Links Mitochondrial Dysfunction to Atherosclerosis in Mice and Pigs. PLoS One 2017; 12:e0170307. [PMID: 28122051 PMCID: PMC5266248 DOI: 10.1371/journal.pone.0170307] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 01/03/2017] [Indexed: 01/05/2023] Open
Abstract
Background Cytochrome oxidase IV complex regulates energy production in mitochondria. Therefore, we determined the relation of COX genes with atherosclerosis in mice and pigs. Methods and results First, we compared atherosclerosis in the aortic arch of age-matched (24 weeks) C57BL/6J control (n = 10), LDL-receptor deficient (n = 8), leptin-deficient ob/ob (n = 10), and double knock-out (lacking LDL-receptor and leptin) mice (n = 12). Low aortic mitochondria-encoded cytochrome oxidase 1 in obese diabetic double knock-out mice was associated with a larger plaque area and higher propensity of M1 macrophages and oxidized LDL. Caloric restriction increased mitochondria-encoded cytochrome oxidase 1 and reduced plaque area and oxidized LDL. This was associated with a reduction of titer of anti-oxidized LDL antibodies, a proxy of systemic oxidative stress. Low of mitochondria-encoded cytochrome oxidase 1 was related to low expression of peroxisome proliferative activated receptors α, δ, and γ and of peroxisome proliferative activated receptor, gamma, co-activator 1 alpha reflecting mitochondrial dysfunction. Caloric restriction increased them. To investigate if there was a diabetic/obesity requirement for mitochondria-encoded cytochrome oxidase 1 to be down-regulated, we then studied atherosclerosis in LAD of hypercholesterolemic pigs (n = 37). Pigs at the end of the study were divided in three groups based on increasing LAD plaque complexity according to Stary (Stary I: n = 12; Stary II: n = 13; Stary III: n = 12). Low mitochondria-encoded cytochrome oxidase 1 in isolated plaque macrophages was associated with more complex coronary plaques and oxidized LDL. Nucleus-encoded cytochrome oxidase 4I1 and cytochrome oxidase 10 did not correlate with plaque complexity and oxidative stress. In mice and pigs, MT-COI was inversely related to insulin resistance. Conclusions Low MT-COI is related to mitochondrial dysfunction, oxidative stress and atherosclerosis and plaque complexity.
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Niemann J, Johne C, Schröder S, Koch F, Ibrahim SM, Schultz J, Tiedge M, Baltrusch S. An mtDNA mutation accelerates liver aging by interfering with the ROS response and mitochondrial life cycle. Free Radic Biol Med 2017; 102:174-187. [PMID: 27890640 DOI: 10.1016/j.freeradbiomed.2016.11.035] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 11/10/2016] [Accepted: 11/21/2016] [Indexed: 12/31/2022]
Abstract
Mitochondrial dysfunction affects liver metabolism, but it remains unclear whether this interferes with normal liver aging. We investigated several mitochondrial pathways in hepatocytes and liver tissue from a conplastic mouse strain compared with the control C57BL/6NTac strain over 18 months of life. The C57BL/6NTac-mtNODLtJ mice differed from C57BL/6NTac mice by a point mutation in mitochondrial-encoded subunit 3 of cytochrome c oxidase. Young C57BL/6NTac-mtNODLtJ mice showed reduced mitochondrial metabolism but similar reactive oxygen species (ROS) production to C57BL/6NTac mice. Whereas ROS increased almost equally up to 9 months in both strains, different mitochondrial adaptation strategies resulted in decreasing ROS in advanced age in C57BL/6NTac mice, but persistent ROS production in C57BL/6NTac-mtNODLtJ mice. Only the conplastic strain developed elongated mitochondrial networks with artificial loop structures, depressed autophagy, high mitochondrial respiration and up-regulated antioxidative response. Our results indicate that mtDNA mutations accelerate liver ballooning degeneration and carry a serious risk of premature organ aging.
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Affiliation(s)
- Jan Niemann
- Institute of Medical Biochemistry and Molecular Biology, University of Rostock, Rostock, Germany
| | - Cindy Johne
- Institute of Medical Biochemistry and Molecular Biology, University of Rostock, Rostock, Germany
| | - Susanne Schröder
- Institute of Medical Biochemistry and Molecular Biology, University of Rostock, Rostock, Germany
| | - Franziska Koch
- Institute of Medical Biochemistry and Molecular Biology, University of Rostock, Rostock, Germany; Institute of Nutritional Physiology "Oskar Kellner","Oskar Kellner", Leibnitz Institute for Farm Animal Biology, Dummerstorf, Germany
| | - Saleh M Ibrahim
- Institute of Experimental Dermatology, University of Lübeck, Lübeck, Germany
| | - Julia Schultz
- Institute of Medical Biochemistry and Molecular Biology, University of Rostock, Rostock, Germany
| | - Markus Tiedge
- Institute of Medical Biochemistry and Molecular Biology, University of Rostock, Rostock, Germany
| | - Simone Baltrusch
- Institute of Medical Biochemistry and Molecular Biology, University of Rostock, Rostock, Germany.
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Castellano-González G, Pichaud N, Ballard JWO, Bessede A, Marcal H, Guillemin GJ. Epigallocatechin-3-gallate induces oxidative phosphorylation by activating cytochrome c oxidase in human cultured neurons and astrocytes. Oncotarget 2016; 7:7426-40. [PMID: 26760769 PMCID: PMC4884929 DOI: 10.18632/oncotarget.6863] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 12/24/2015] [Indexed: 12/24/2022] Open
Abstract
Mitochondrial dysfunction and resulting energy impairment have been identified as features of many neurodegenerative diseases. Whether this energy impairment is the cause of the disease or the consequence of preceding impairment(s) is still under discussion, however a recovery of cellular bioenergetics would plausibly prevent or improve the pathology. In this study, we screened different natural molecules for their ability to increase intracellular adenine triphosphate purine (ATP). Among them, epigallocatechin-3-gallate (EGCG), a polyphenol from green tea, presented the most striking results. We found that it increases ATP production in both human cultured astrocytes and neurons with different kinetic parameters and without toxicity. Specifically, we showed that oxidative phosphorylation in human cultured astrocytes and neurons increased at the level of the routine respiration on the cells pre-treated with the natural molecule. Furthermore, EGCG-induced ATP production was only blocked by sodium azide (NaN3) and oligomycin, inhibitors of cytochrome c oxidase (CcO; complex IV) and ATP synthase (complex V) respectively. These findings suggest that the EGCG modulates CcO activity, as confirmed by its enzymatic activity. CcO is known to be regulated differently in neurons and astrocytes. Accordingly, EGCG treatment is acting differently on the kinetic parameters of the two cell types. To our knowledge, this is the first study showing that EGCG promotes CcO activity in human cultured neurons and astrocytes. Considering that CcO dysfunction has been reported in patients having neurodegenerative diseases such as Alzheimer's disease (AD), we therefore suggest that EGCG could restore mitochondrial function and prevent subsequent loss of synaptic function.
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Affiliation(s)
- Gloria Castellano-González
- MND and Neurodegenerative Diseases Research Group, Australian School of Advanced Medicine (ASAM), Macquarie University, Sydney, Australia
| | - Nicolas Pichaud
- Department of Biological and Environmental Sciences, University of Gothenburg, Göteborg, Sweden
| | - J William O Ballard
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, Australia
| | | | - Helder Marcal
- Topical Therapeutics Research Group, School of Medical Sciences, The University of New South Wales, Sydney, Australia
| | - Gilles J Guillemin
- MND and Neurodegenerative Diseases Research Group, Australian School of Advanced Medicine (ASAM), Macquarie University, Sydney, Australia
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