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Adzigbli L, Ponsuksili S, Sokolova I. Mitochondrial responses to constant and cyclic hypoxia depend on the oxidized fuel in a hypoxia-tolerant marine bivalve Crassostrea gigas. Sci Rep 2024; 14:9658. [PMID: 38671046 PMCID: PMC11053104 DOI: 10.1038/s41598-024-60261-w] [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: 10/04/2023] [Accepted: 04/21/2024] [Indexed: 04/28/2024] Open
Abstract
Sessile benthic organisms like oysters inhabit the intertidal zone, subject to alternating hypoxia and reoxygenation (H/R) episodes during tidal movements, impacting respiratory chain activities and metabolome compositions. We investigated the effects of constant severe hypoxia (90 min at ~ 0% O2 ) followed by 10 min reoxygenation, and cyclic hypoxia (5 cycles of 15 min at ~ 0% O2 and 10 min reoxygenation) on isolated mitochondria from the gill and the digestive gland of Crassostrea gigas respiring on pyruvate, palmitate, or succinate. Constant hypoxia suppressed oxidative phosphorylation (OXPHOS), particularly during Complex I-linked substrates oxidation. It had no effect on mitochondrial reactive oxygen species (ROS) efflux but increased fractional electron leak (FEL). In mitochondria oxidizing Complex I substrates, exposure to cyclic hypoxia prompted a significant drop after the first H/R cycle. In contrast, succinate-driven respiration only showed significant decline after the third to fifth H/R cycle. ROS efflux saw little change during cyclic hypoxia regardless of the oxidized substrate, but Complex I-driven FEL tended to increase with each subsequent H/R cycle. These observations suggest that succinate may serve as a beneficial stress fuel under H/R conditions, aiding in the post-hypoxic recovery of oysters by reducing oxidative stress and facilitating rapid ATP re-synthesis. The impacts of constant and cyclic hypoxia of similar duration on mitochondrial respiration and oxidative lesions in the proteins were comparable indicating that the mitochondrial damage is mostly determined by the lack of oxygen and mitochondrial depolarization. The ROS efflux in the mitochondria of oysters was minimally affected by oxygen fluctuations indicating that tight regulation of ROS production may contribute to robust mitochondrial phenotype of oysters and protect against H/R induced stress.
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Affiliation(s)
- Linda Adzigbli
- Institute for Farm Animal Biology, Institute of Genome Biology, Dummerstorf, Germany
- Department of Marine Biology, Institute for Biological Sciences, University of Rostock, Rostock, Germany
| | - Siriluck Ponsuksili
- Institute for Farm Animal Biology, Institute of Genome Biology, Dummerstorf, Germany
| | - Inna Sokolova
- Department of Marine Biology, Institute for Biological Sciences, University of Rostock, Rostock, Germany.
- Department of Maritime Systems, Interdisciplinary Faculty, University of Rostock, Rostock, Germany.
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Andrés CMC, Pérez de la Lastra JM, Juan CA, Plou FJ, Pérez-Lebeña E. Myeloid-Derived Suppressor Cells in Cancer and COVID-19 as Associated with Oxidative Stress. Vaccines (Basel) 2023; 11:218. [PMID: 36851096 PMCID: PMC9966263 DOI: 10.3390/vaccines11020218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 01/14/2023] [Accepted: 01/17/2023] [Indexed: 01/20/2023] Open
Abstract
Myeloid-derived suppressor cells MDSCs are a heterogeneous population of cells that expand beyond their physiological regulation during pathologies such as cancer, inflammation, bacterial, and viral infections. Their key feature is their remarkable ability to suppress T cell and natural killer NK cell responses. Certain risk factors for severe COVID-19 disease, such as obesity and diabetes, are associated with oxidative stress. The resulting inflammation and oxidative stress can negatively impact the host. Similarly, cancer cells exhibit a sustained increase in intrinsic ROS generation that maintains the oncogenic phenotype and drives tumor progression. By disrupting endoplasmic reticulum calcium channels, intracellular ROS accumulation can disrupt protein folding and ultimately lead to proteostasis failure. In cancer and COVID-19, MDSCs consist of the same two subtypes (PMN-MSDC and M-MDSC). While the main role of polymorphonuclear MDSCs is to dampen the response of T cells and NK killer cells, they also produce reactive oxygen species ROS and reactive nitrogen species RNS. We here review the origin of MDSCs, their expansion mechanisms, and their suppressive functions in the context of cancer and COVID-19 associated with the presence of superoxide anion •O2- and reactive oxygen species ROS.
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Affiliation(s)
| | - José Manuel Pérez de la Lastra
- Cinquima Institute and Department of Organic Chemistry, Faculty of Sciences, Valladolid University, Paseo de Belén 7, 47011 Valladolid, Spain
| | - Celia Andrés Juan
- Institute of Natural Products and Agrobiology, CSIC-Spanish Research Council, Avda. Astrofísico Fco. Sánchez, 3, 38206 La Laguna, Spain
| | - Francisco J. Plou
- Institute of Catalysis and Petrochemistry, CSIC-Spanish Research Council, 28049 Madrid, Spain
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Kotsyuba E, Dyachuk V. Role of the Neuroendocrine System of Marine Bivalves in Their Response to Hypoxia. Int J Mol Sci 2023; 24:ijms24021202. [PMID: 36674710 PMCID: PMC9865615 DOI: 10.3390/ijms24021202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 12/28/2022] [Accepted: 01/04/2023] [Indexed: 01/11/2023] Open
Abstract
Mollusks comprise one of the largest phylum of marine invertebrates. With their great diversity of species, various degrees of mobility, and specific behavioral strategies, they haveoccupied marine, freshwater, and terrestrial habitats and play key roles in many ecosystems. This success is explained by their exceptional ability to tolerate a wide range of environmental stresses, such as hypoxia. Most marine bivalvemollusksare exposed to frequent short-term variations in oxygen levels in their marine or estuarine habitats. This stressfactor has caused them to develop a wide variety of adaptive strategies during their evolution, enabling to mobilize rapidly a set of behavioral, physiological, biochemical, and molecular defenses that re-establishing oxygen homeostasis. The neuroendocrine system and its related signaling systems play crucial roles in the regulation of various physiological and behavioral processes in mollusks and, hence, can affect hypoxiatolerance. Little effort has been made to identify the neurotransmitters and genes involved in oxygen homeostasis regulation, and the molecular basis of the differences in the regulatory mechanisms of hypoxia resistance in hypoxia-tolerant and hypoxia-sensitive bivalve species. Here, we summarize current knowledge about the involvement of the neuroendocrine system in the hypoxia stress response, and the possible contributions of various signaling molecules to this process. We thusprovide a basis for understanding the molecular mechanisms underlying hypoxic stress in bivalves, also making comparisons with data from related studies on other species.
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Yu D, Zhai Y, He P, Jia R. Comprehensive Transcriptomic and Metabolomic Analysis of the Litopenaeus vannamei Hepatopancreas After WSSV Challenge. Front Immunol 2022; 13:826794. [PMID: 35222409 PMCID: PMC8867067 DOI: 10.3389/fimmu.2022.826794] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 01/21/2022] [Indexed: 11/13/2022] Open
Abstract
Litopenaeus vannamei is the major farmed shrimp species worldwide. White spot disease due to white spot syndrome virus (WSSV) is severely affecting shrimp worldwide, causing extensive economic losses in L. vannamei culture. This is the first study that applied combined transcriptomic and metabolomic analysis to study the effects on the L. vannamei hepatopancreas after WSSV challenge. Our transcriptomic data revealed differentially expressed genes (DEGs) associated with immunity, apoptosis, the cytoskeleton and the antioxidant system in the hepatopancreas of L. vannamei. Metabolomic results showed that WSSV disrupts metabolic processes including amino acid metabolism, lipid metabolism and nucleotide metabolism. After challenged by WSSV, immune-related DEGs and differential metabolites (DMs) were detected in the hepatopancreas of L. vannamei, indicating that WSSV may damage the immune system and cause metabolic disorder in the shrimp. In summary, these results provide new insights into the molecular mechanisms underlying L. vannamei's response to WSSV.
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Affiliation(s)
- Dianjiang Yu
- College of Marine Ecology and Environment, Shanghai Ocean University, Shanghai, China
| | - Yufeng Zhai
- College of Marine Ecology and Environment, Shanghai Ocean University, Shanghai, China
| | - Peimin He
- College of Marine Ecology and Environment, Shanghai Ocean University, Shanghai, China
| | - Rui Jia
- College of Marine Ecology and Environment, Shanghai Ocean University, Shanghai, China
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Effect of Air Exposure-Induced Hypoxia on Neurotransmitters and Neurotransmission Enzymes in Ganglia of the Scallop Azumapecten farreri. Int J Mol Sci 2022; 23:ijms23042027. [PMID: 35216143 PMCID: PMC8878441 DOI: 10.3390/ijms23042027] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 02/09/2022] [Accepted: 02/09/2022] [Indexed: 02/04/2023] Open
Abstract
The nervous system expresses neuromolecules that play a crucial role in regulating physiological processes. Neuromolecule synthesis can be regulated by oxygen-dependent enzymes. Bivalves are a convenient model for studying air exposure-induced hypoxia. Here, we studied the effects of hypoxia on the expression and dynamics of neurotransmitters, and on neurotransmitter enzyme distribution, in the central nervous system (CNS) of the scallop Azumapecten farreri. We analyzed the expression of the neurotransmitters FMRFamide and serotonin (5-HT) and the choline acetyltransferase (CHAT) and universal NO-synthase (uNOS) enzymes during air exposure-induced hypoxia. We found that, in early-stage hypoxia, total serotonin content decreased in some CNS regions but increased in others. CHAT-lir cell numbers increased in all ganglia after hypoxia; CHAT probably appears de novo in accessory ganglia. Short-term hypoxia caused increased uNOS-lir cell numbers, while long-term exposure led to a reduction in their number. Thus, hypoxia weakly influences the number of FMRFamide-lir neurons in the visceral ganglion and does not affect peptide expression in the pedal ganglion. Ultimately, we found that the localization and level of synthesis of neuromolecules, and the numbers of cells expressing these molecules, vary in the scallop CNS during hypoxia exposure. This indicates their possible involvement in hypoxia resistance mechanisms.
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Adzigbli L, Sokolov EP, Ponsuksili S, Sokolova IM. Tissue- and substrate-dependent mitochondrial responses to acute hypoxia-reoxygenation stress in a marine bivalve Crassostrea gigas (Thunberg, 1793). J Exp Biol 2021; 225:273950. [PMID: 34904172 DOI: 10.1242/jeb.243304] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 12/07/2021] [Indexed: 11/20/2022]
Abstract
Hypoxia is a major stressor for aquatic organisms, yet intertidal organisms like the oyster Crassostrea gigas are adapted to frequent oxygen fluctuations by metabolically adjusting to shifts in oxygen and substrate availability during hypoxia-reoxygenation (H/R). We investigated the effects of acute H/R stress (15 min at ∼0% O2, and 10 min reoxygenation) on isolated mitochondria from the gill and the digestive gland of C. gigas respiring on different substrates (pyruvate, glutamate, succinate, palmitate and their mixtures). Gill mitochondria showed better capacity for amino acid and fatty acid oxidation compared to the mitochondria from the digestive gland. Mitochondrial responses to H/R stress strongly depended on the substrate and the activity state of mitochondria. In mitochondria oxidizing NADH-linked substrates exposure to H/R stress suppressed oxygen consumption and ROS generation in the resting state, whereas in the ADP-stimulated state, ROS production increased despite little change in respiration. As a result, electron leak (measured as H2O2 to O2 ratio) increased after H/R stress in the ADP-stimulated mitochondria with NADH-linked substrates. In contrast, H/R exposure stimulated succinate-driven respiration without an increase in electron leak. Reverse electron transport (RET) did not significantly contribute to succinate-driven ROS production in oyster mitochondria except for a slight increase in the OXPHOS state during post-hypoxic recovery. A decrease in NADH-driven respiration and ROS production, enhanced capacity for succinate oxidation and resistance to RET might assist in post-hypoxic recovery of oysters mitigating oxidative stress and supporting rapid ATP re-synthesis during oxygen fluctuations such as commonly observed in estuaries and intertidal zones.
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Affiliation(s)
- Linda Adzigbli
- Leibniz Institute for Farm Animal Biology (FBN), Institute of Genome Biology, Dummerstorf, Germany.,Department of Marine Biology, Institute for Biological Sciences, University of Rostock, Rostock, Germany
| | - Eugene P Sokolov
- Leibniz Institute for Baltic Sea Research, Leibniz Science Campus Phosphorus Research, Warnemünde, Rostock, Germany
| | - Siriluck Ponsuksili
- Leibniz Institute for Farm Animal Biology (FBN), Institute of Genome Biology, Dummerstorf, Germany
| | - Inna M Sokolova
- Department of Marine Biology, Institute for Biological Sciences, University of Rostock, Rostock, Germany.,Department of Maritime Systems, Interdisciplinary Faculty, University of Rostock, Rostock, Germany
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Škodová-Sveráková I, Záhonová K, Juricová V, Danchenko M, Moos M, Baráth P, Prokopchuk G, Butenko A, Lukáčová V, Kohútová L, Bučková B, Horák A, Faktorová D, Horváth A, Šimek P, Lukeš J. Highly flexible metabolism of the marine euglenozoan protist Diplonema papillatum. BMC Biol 2021; 19:251. [PMID: 34819072 PMCID: PMC8611851 DOI: 10.1186/s12915-021-01186-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 11/08/2021] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND The phylum Euglenozoa is a group of flagellated protists comprising the diplonemids, euglenids, symbiontids, and kinetoplastids. The diplonemids are highly abundant and speciose, and recent tools have rendered the best studied representative, Diplonema papillatum, genetically tractable. However, despite the high diversity of diplonemids, their lifestyles, ecological functions, and even primary energy source are mostly unknown. RESULTS We designed a metabolic map of D. papillatum cellular bioenergetic pathways based on the alterations of transcriptomic, proteomic, and metabolomic profiles obtained from cells grown under different conditions. Comparative analysis in the nutrient-rich and nutrient-poor media, as well as the absence and presence of oxygen, revealed its capacity for extensive metabolic reprogramming that occurs predominantly on the proteomic rather than the transcriptomic level. D. papillatum is equipped with fundamental metabolic routes such as glycolysis, gluconeogenesis, TCA cycle, pentose phosphate pathway, respiratory complexes, β-oxidation, and synthesis of fatty acids. Gluconeogenesis is uniquely dominant over glycolysis under all surveyed conditions, while the TCA cycle represents an eclectic combination of standard and unusual enzymes. CONCLUSIONS The identification of conventional anaerobic enzymes reflects the ability of this protist to survive in low-oxygen environments. Furthermore, its metabolism quickly reacts to restricted carbon availability, suggesting a high metabolic flexibility of diplonemids, which is further reflected in cell morphology and motility, correlating well with their extreme ecological valence.
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Affiliation(s)
- Ingrid Škodová-Sveráková
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic.
- Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia.
| | - Kristína Záhonová
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
- Faculty of Science, Charles University, BIOCEV, Vestec, Czech Republic
| | - Valéria Juricová
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
- Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic
| | - Maksym Danchenko
- Institute of Chemistry, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Martin Moos
- Institute of Entomology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
| | - Peter Baráth
- Institute of Chemistry, Slovak Academy of Sciences, Bratislava, Slovakia
- Medirex Group Academy n.o., Trnava, Slovakia
| | - Galina Prokopchuk
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
| | - Anzhelika Butenko
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
- Faculty of Science, University of Ostrava, Ostrava, Czech Republic
| | | | - Lenka Kohútová
- Institute of Chemistry, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Barbora Bučková
- Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia
| | - Aleš Horák
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
- Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic
| | - Drahomíra Faktorová
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
- Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic
| | - Anton Horváth
- Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia
| | - Petr Šimek
- Institute of Entomology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
| | - Julius Lukeš
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic.
- Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic.
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Alfaro AC, Nguyen TV, Venter L, Ericson JA, Sharma S, Ragg NLC, Mundy C. The Effects of Live Transport on Metabolism and Stress Responses of Abalone ( Haliotis iris). Metabolites 2021; 11:748. [PMID: 34822406 PMCID: PMC8623598 DOI: 10.3390/metabo11110748] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 10/22/2021] [Accepted: 10/27/2021] [Indexed: 12/18/2022] Open
Abstract
The New Zealand abalone industry relies mostly on the export of processed products to distant Asian markets, notably China. Over the past five years, live export of high quality abalone from New Zealand has proven successful. However, transport of live animals is associated with multiple stressors that affect survival and meat quality at the end of the transport phase. Better understanding of transport-derived stress is needed to improve transport conditions and recovery at destination to ensure high product quality and safety throughout the supply chain. To this end, we applied an untargeted GC-MS-based metabolomics approach to examine the changes in metabolite profiles of abalone after a 2-day transport event and subsequent water re-immersion for 2 days. The results revealed alterations of many metabolites in the haemolymph and muscle of post-transported abalone. Decreased concentrations of many amino acids suggest high energy demands for metabolism and stress responses of transported abalone, while increases of other amino acids may indicate active osmoregulation and/or protein degradation due to oxidative stress and apoptosis. The accumulation of citric acid cycle intermediates and anaerobic end-products are suggestive of hypoxia stress and a shift from aerobic to anaerobic metabolism (resulting from aerial exposure). Interestingly, some features in the metabolite profile of reimmersed abalone resembled those of pre-transported individuals, suggesting progressive recovery after reimmersion in water. Evidence of recovery was observed in the reduction of some stress biomarkers (e.g., lactic acid, succinic acid) following reimmersion. This study revealed insights into the metabolic responses to transport stress in abalone and highlights the importance of reimmersion practices in the supply chain of live animal exports.
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Affiliation(s)
- Andrea C. Alfaro
- Aquaculture Biotechnology Research Group, School of Science, Auckland University of Technology, Private Bag 92006, Auckland 1142, New Zealand; (T.V.N.); (L.V.); (S.S.)
| | - Thao V. Nguyen
- Aquaculture Biotechnology Research Group, School of Science, Auckland University of Technology, Private Bag 92006, Auckland 1142, New Zealand; (T.V.N.); (L.V.); (S.S.)
- NTT Hi-Tech Institute, Nguyen Tat Thanh University, Ho Chi Minh City 755414, Vietnam
| | - Leonie Venter
- Aquaculture Biotechnology Research Group, School of Science, Auckland University of Technology, Private Bag 92006, Auckland 1142, New Zealand; (T.V.N.); (L.V.); (S.S.)
| | - Jessica A. Ericson
- Cawthron Institute, Private Bag 2, Nelson 7042, New Zealand; (J.A.E.); (N.L.C.R.)
| | - Shaneel Sharma
- Aquaculture Biotechnology Research Group, School of Science, Auckland University of Technology, Private Bag 92006, Auckland 1142, New Zealand; (T.V.N.); (L.V.); (S.S.)
| | - Norman L. C. Ragg
- Cawthron Institute, Private Bag 2, Nelson 7042, New Zealand; (J.A.E.); (N.L.C.R.)
| | - Craig Mundy
- IMAS Fisheries and Aquaculture Centre, College of Science and Engineering, University of Tasmania, Taroona, Hobart 7001, Australia;
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Sokolova I. Bioenergetics in environmental adaptation and stress tolerance of aquatic ectotherms: linking physiology and ecology in a multi-stressor landscape. J Exp Biol 2021; 224:224/Suppl_1/jeb236802. [PMID: 33627464 DOI: 10.1242/jeb.236802] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Energy metabolism (encompassing energy assimilation, conversion and utilization) plays a central role in all life processes and serves as a link between the organismal physiology, behavior and ecology. Metabolic rates define the physiological and life-history performance of an organism, have direct implications for Darwinian fitness, and affect ecologically relevant traits such as the trophic relationships, productivity and ecosystem engineering functions. Natural environmental variability and anthropogenic changes expose aquatic ectotherms to multiple stressors that can strongly affect their energy metabolism and thereby modify the energy fluxes within an organism and in the ecosystem. This Review focuses on the role of bioenergetic disturbances and metabolic adjustments in responses to multiple stressors (especially the general cellular stress response), provides examples of the effects of multiple stressors on energy intake, assimilation, conversion and expenditure, and discusses the conceptual and quantitative approaches to identify and mechanistically explain the energy trade-offs in multiple stressor scenarios, and link the cellular and organismal bioenergetics with fitness, productivity and/or ecological functions of aquatic ectotherms.
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Affiliation(s)
- Inna Sokolova
- Marine Biology Department, Institute of Biological Sciences, University of Rostock, 18059 Rostock, Germany .,Department of Maritime Systems, Interdisciplinary Faculty, University of Rostock, 18059 Rostock, Germany
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Bélanger M, Turcotte F, Tremblay R, Lambert Y, Litvak M, Audet C. Influence of the timing of weaning on growth and survival of juvenile winter flounder (Pseudopleuronectes americanus). CAN J ZOOL 2018. [DOI: 10.1139/cjz-2018-0004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Metamorphosis is a critical developmental stage that presents particular challenges in fish aquaculture. The sharp increase in mortality that accompanies this transformation has often been attributed to nutritional deficiencies. Providing live feed (the rotifer Brachionus plicatilis Müller, 1786 and the brine shrimp Artemia salina (Linnaeus, 1758)) during the larval stages is costly and labour intensive, which explains why much effort has been put on early weaning. However, previous observations in winter flounder (Pseudopleuronectes americanus (Walbaum, 1792)) indicate that juveniles weaned after settlement had better survival than those weaned at the larval stage. In this study, we tested whether late weaning (at settlement (W0) and groups maintained on co-feeding for 1 month (W1), two months (W2), or 3 months (W3) after settlement) could improve juvenile survival and lipid composition. Our results demonstrated that maintaining co-feeding beyond the larval stage was essential for after-settlement survival. Juveniles co-fed until 90 days after settlement were 32.5% heavier. Analyses of fatty acid trophic markers suggested that juveniles preferentially fed on enriched rotifers rather than inert food. No pigmentation or fin erosion problems were observed in any of the weaning treatments, which indicates good rearing conditions.
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Affiliation(s)
- M. Bélanger
- Institut des sciences de la mer de Rimouski, Université du Québec à Rimouski, 310, allée des Ursulines, Rimouski, QC G5L 3A1, Canada
| | - F. Turcotte
- Institut des sciences de la mer de Rimouski, Université du Québec à Rimouski, 310, allée des Ursulines, Rimouski, QC G5L 3A1, Canada
| | - R. Tremblay
- Institut des sciences de la mer de Rimouski, Université du Québec à Rimouski, 310, allée des Ursulines, Rimouski, QC G5L 3A1, Canada
| | - Y. Lambert
- Maurice Lamontagne Institute, Fisheries and Oceans Canada, 850, route de la Mer, Mont-Joli, QC G5H 3Z4, Canada
| | - M.K. Litvak
- Department of Biology, Mount Allison University, Sackville, NB E4L 1G7, Canada
| | - C. Audet
- Institut des sciences de la mer de Rimouski, Université du Québec à Rimouski, 310, allée des Ursulines, Rimouski, QC G5L 3A1, Canada
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Zheng JL, Yuan SS, Shen B, Wu CW. Organ-specific effects of low-dose zinc pre-exposure on high-dose zinc induced mitochondrial dysfunction in large yellow croaker Pseudosciaena crocea. FISH PHYSIOLOGY AND BIOCHEMISTRY 2017; 43:653-661. [PMID: 27909949 DOI: 10.1007/s10695-016-0319-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Accepted: 11/21/2016] [Indexed: 06/06/2023]
Abstract
The study was carried out to evaluate the effects of low-dose zinc (Zn) pre-exposure on survival rate, new Zn accumulation, and mitochondrial bioenergetics in the liver and spleen of large yellow croaker exposed to high-dose Zn. To the end, fish were pre-exposed to 0 and 2 mg L-1 Zn for 48 h and post-exposed to 0 and 12 mg L-1 Zn for 48 h. Twelve milligrams Zn per liter exposure alone reduced survival rate, but the effect did not appear in the 2 mg L-1 Zn pre-exposure groups. Two milligrams per liter Zn pre-exposure also ameliorated 12 mg Zn L-1 induced new Zn accumulation, reactive oxygen species (ROS) levels, and mitochondrial swelling in the liver. However, these effects did not appear in the spleen. In the liver, 2 mg L-1 Zn pre-exposure apparently relieved 12 mg L-1 Zn induced down-regulation of activities of ATP synthase (F-ATPase), succinate dehydrogenase (SDH), and malate dehydrogenase (MDH). The mRNA levels of these genes remained relatively stable in fish exposed to 12 mg L-1 Zn alone, but increased in fish exposed to 12 mg L-1 Zn with 2 mg L-1 Zn pre-treatment. In the spleen, 2 mg Zn L-1 pre-exposure did not mitigate the down-regulation of mRNA levels of genes and activities of relative enzymes induced by 12 mg L-1 Zn. In conclusion, our study demonstrated low-dose zinc pre-exposure ameliorated high-dose zinc induced mitochondrial dysfunction in the liver but not in the spleen of large yellow croaker, indicating an organ-specific effect.
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Affiliation(s)
- Jia-Lang Zheng
- National Engineering Research Center of Marine Facilities Aquaculture, Zhejiang Ocean University, Zhoushan, 316022, People's Republic of China
| | - Shuang-Shuang Yuan
- National Engineering Research Center of Marine Facilities Aquaculture, Zhejiang Ocean University, Zhoushan, 316022, People's Republic of China
| | - Bin Shen
- National Engineering Research Center of Marine Facilities Aquaculture, Zhejiang Ocean University, Zhoushan, 316022, People's Republic of China
| | - Chang-Wen Wu
- National Engineering Research Center of Marine Facilities Aquaculture, Zhejiang Ocean University, Zhoushan, 316022, People's Republic of China.
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Drozdov KA, Drozdov AL. Anaerobic glycolysis in sea urchins as adaptation to life in a habitat lacking oxygen. BIOL BULL+ 2017. [DOI: 10.1134/s1062359016060066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Stefano GB, Kream RM. Glycolytic Coupling to Mitochondrial Energy Production Ensures Survival in an Oxygen Rich Environment. Med Sci Monit 2016; 22:2571-5. [PMID: 27439008 PMCID: PMC4957629 DOI: 10.12659/msm.899610] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The mitochondrion exhibits biochemical and functional variations that emerged by random chance as an evolutionary survival strategy, which include enhanced energy production driven by anaerobic respiratory mechanisms. In invertebrates, this mitochondrial anaerobic respiration permits survival at a lower energy state suited for this type of environment while yielding more ATP than by glycolysis alone. This ability provides a protective existential advantage in naturally occurring hypoxic environments via diminished free radical generation. In the blue mussel Mytilus edulis and other marine organisms, a functionally active mitochondrial anaerobic respiratory mechanism tailored to hypoxic conditions reflects an evolutionary adaptation/reworking of ancient metabolic pathways. Components of these pathways were also discovered and characterized as metabolic intermediates in plant parasites, specifically crown gall tumors. Mechanistic similarities between anaerobically functioning mitochondria in M. edulis and crown gall tissues and metabolic processes in human tumors are known to occur, demonstrating commonalities in diverse life energy processes. Furthermore, cytoplasmic glycolytic processes are now shown also to exhibit a dynamic capacity for enhanced energy generation by increasing its efficiency in hypoxic environments, making it equally dynamic in meeting its cellular survival goal.
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Affiliation(s)
- George B Stefano
- Department of Research, MitoGenetics Research Institute, Farmingdale, NY, USA
| | - Richard M Kream
- Department of Research, MitoGenetics Research Institute, Farmingdale, NY, USA
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Sardenne F, Ménard F, Degroote M, Fouché E, Guillou G, Lebreton B, Hollanda SJ, Bodin N. Methods of lipid-normalization for multi-tissue stable isotope analyses in tropical tuna. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2015; 29:1253-1267. [PMID: 26395609 DOI: 10.1002/rcm.7215] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Revised: 04/13/2015] [Accepted: 04/17/2015] [Indexed: 06/05/2023]
Abstract
RATIONALE The bias associated with lipid contents in fish tissues is a recalcitrant topic for trophic studies using stable isotopes. Lipids are depleted in the heavy carbon isotope ((13)C) and the lipid content varies considerably among species, tissues and in both time and space. We have applied and assessed different correction methods for tropical tuna tissues. METHODS We tested two types of normalization methods to deal with variable lipid content in liver, gonads, and white and red muscles of yellowfin, bigeye and skipjack tuna: a chemical extraction using dichloromethane and a mathematical correction based on three modeling approaches (linear, non-linear and mass balance models). We measured isotopic ratios of bulk and lipid-free tissues and assessed the predictive ability of the correction models with the lipid-free measurements. The parameters of the models were estimated from our dataset and from results from published studies on other species. RESULTS Comparison between bulk, lipid-free and lipid-corrected isotopic ratios demonstrated that (1) chemical extraction using dichloromethane did not affect δ(15)N values; (2) the change in δ(13)C values after extraction was tissue-specific; (3) lipid-normalization models using published parameter estimates failed to predict lipid-corrected δ(13)C values; and (4) linear and non-linear models using parameters estimated for each tissue from our dataset provided accurate δ(13)C predictions for all tissues, and mass balance model for white muscle only. CONCLUSIONS Models using published estimates for parameters from other species cannot be used. Based on a range of lipid content that do not exceed 45%, we recommend the linear model to correct the bulk δ(13)C values in the investigated tissues but the parameters have to be estimated from a proportion of the original data for which chemical extraction is required and the isotopic values of bulk and lipid-free tissues are measured.
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Affiliation(s)
- Fany Sardenne
- IRD, UMR MARine Biodiversity Exploitation and Conservation (MARBEC), Avenue Jean Monnet, Sète, France
- IRD, UMR MARine Biodiversity Exploitation and Conservation (MARBEC), Fishing Port, Victoria, Seychelles
| | - Frédéric Ménard
- IRD, Mediterranean Institute of Oceanography (MIO), Aix-Marseille Université/CNRS/IRD/Université de Toulon, 13288, Marseille, France
| | - Maxime Degroote
- IRD, UMR MARine Biodiversity Exploitation and Conservation (MARBEC), Avenue Jean Monnet, Sète, France
| | - Edwin Fouché
- IRD, UMR MARine Biodiversity Exploitation and Conservation (MARBEC), Avenue Jean Monnet, Sète, France
- INRA, UMR TOXALIM (Research Centre in Food Toxicology), Toulouse, France
| | - Gaël Guillou
- CNRS-Université de la Rochelle, UMR Littoral Environnement et Sociétés (LIENSs), 2 rue Olympe de Gouges, 17000, La Rochelle, France
| | - Benoit Lebreton
- CNRS-Université de la Rochelle, UMR Littoral Environnement et Sociétés (LIENSs), 2 rue Olympe de Gouges, 17000, La Rochelle, France
| | | | - Nathalie Bodin
- IRD, UMR MARine Biodiversity Exploitation and Conservation (MARBEC), Fishing Port, Victoria, Seychelles
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Yang W, Catalanotti C, Wittkopp TM, Posewitz MC, Grossman AR. Algae after dark: mechanisms to cope with anoxic/hypoxic conditions. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2015; 82:481-503. [PMID: 25752440 DOI: 10.1111/tpj.12823] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 02/28/2015] [Accepted: 03/03/2015] [Indexed: 06/04/2023]
Abstract
Chlamydomonas reinhardtii is a unicellular, soil-dwelling (and aquatic) green alga that has significant metabolic flexibility for balancing redox equivalents and generating ATP when it experiences hypoxic/anoxic conditions. The diversity of pathways available to ferment sugars is often revealed in mutants in which the activities of specific branches of fermentative metabolism have been eliminated; compensatory pathways that have little activity in parental strains under standard laboratory fermentative conditions are often activated. The ways in which these pathways are regulated and integrated have not been extensively explored. In this review, we primarily discuss the intricacies of dark anoxic metabolism in Chlamydomonas, but also discuss aspects of dark oxic metabolism, the utilization of acetate, and the relatively uncharacterized but critical interactions that link chloroplastic and mitochondrial metabolic networks.
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Affiliation(s)
- Wenqiang Yang
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA
| | - Claudia Catalanotti
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA
| | - Tyler M Wittkopp
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA
- Department of Biology, Stanford University, Stanford, CA, 94305, USA
| | - Matthew C Posewitz
- Department of Chemistry and Geochemistry, Colorado School of Mines, Golden, CO, 80401, USA
| | - Arthur R Grossman
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA
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16
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Jiang Q, Zhang W, Tan H, Pan D, Yang Y, Ren Q, Yang J. Analysis of gene expression changes, caused by exposure to nitrite, in metabolic and antioxidant enzymes in the red claw crayfish, Cherax quadricarinatus. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2014; 104:423-428. [PMID: 24680578 DOI: 10.1016/j.ecoenv.2013.10.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Revised: 10/23/2013] [Accepted: 10/28/2013] [Indexed: 06/03/2023]
Abstract
We evaluated the effect of acute exposure to nitrite on expression of antioxidant and metabolic enzyme genes in gill tissue of advanced juvenile Cherax quadricarinatus. A 48h nitrite exposure was conducted, using four test concentrations (NO2-N=0.5, 1, 1.5 and 2mg L(-1)) plus a control group. The relative mRNA expression of mitochondrial manganese superoxide dismutase (mMnSOD), cytosolic MnSOD (cMnSOD), extracellular copper/zinc SOD (exCu/ZnSOD), catalase (CAT), glutathione S-transferase (GST), arginine kinase (AK), glutamate dehydrogenase (GDH), mitochondrial malate dehydrogenase (mMDH), Na(+)/K(+)-ATPase α-subunit and phosphoenolpyruvate carboxykinase (PEPCK) in gill tissue was measured. Significantly increased mRNA expression was observed for all the antioxidant enzymes after 12 and 24h. After 48h, they all decreased at high nitrite concentrations. The gene expression levels of AK, GDH, mMDH and Na(+)/K(+)-ATPase α-subunit showed similar trends as the antioxidant enzymes. Significant depression of gene expression levels of PEPCK occurred throughout the experimental time at high nitrite concentrations. The results indicated that nitrite could induce oxidative and metabolic stress in C. quadricarinatus, in a time dependent manner, which suggests they could be helpful in predicting sublethal nitrite toxicity and useful in environmental monitoring studies.
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Affiliation(s)
- Qichen Jiang
- Jiangsu Province Key Laboratory for Aquatic Live Food, Jiangsu Province Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210023, PR China
| | - Wenyi Zhang
- Jiangsu Province Key Laboratory for Aquatic Live Food, Jiangsu Province Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210023, PR China
| | - Hongyue Tan
- Jiangsu Province Key Laboratory for Aquatic Live Food, Jiangsu Province Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210023, PR China
| | - Dongmei Pan
- Jiangsu Province Key Laboratory for Aquatic Live Food, Jiangsu Province Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210023, PR China
| | - Yuanhao Yang
- Jiangsu Province Key Laboratory for Aquatic Live Food, Jiangsu Province Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210023, PR China
| | - Qian Ren
- Jiangsu Province Key Laboratory for Aquatic Live Food, Jiangsu Province Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210023, PR China
| | - Jiaxin Yang
- Jiangsu Province Key Laboratory for Aquatic Live Food, Jiangsu Province Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210023, PR China.
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17
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Müller M, Mentel M, van Hellemond JJ, Henze K, Woehle C, Gould SB, Yu RY, van der Giezen M, Tielens AGM, Martin WF. Biochemistry and evolution of anaerobic energy metabolism in eukaryotes. Microbiol Mol Biol Rev 2012; 76:444-95. [PMID: 22688819 PMCID: PMC3372258 DOI: 10.1128/mmbr.05024-11] [Citation(s) in RCA: 498] [Impact Index Per Article: 41.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Major insights into the phylogenetic distribution, biochemistry, and evolutionary significance of organelles involved in ATP synthesis (energy metabolism) in eukaryotes that thrive in anaerobic environments for all or part of their life cycles have accrued in recent years. All known eukaryotic groups possess an organelle of mitochondrial origin, mapping the origin of mitochondria to the eukaryotic common ancestor, and genome sequence data are rapidly accumulating for eukaryotes that possess anaerobic mitochondria, hydrogenosomes, or mitosomes. Here we review the available biochemical data on the enzymes and pathways that eukaryotes use in anaerobic energy metabolism and summarize the metabolic end products that they generate in their anaerobic habitats, focusing on the biochemical roles that their mitochondria play in anaerobic ATP synthesis. We present metabolic maps of compartmentalized energy metabolism for 16 well-studied species. There are currently no enzymes of core anaerobic energy metabolism that are specific to any of the six eukaryotic supergroup lineages; genes present in one supergroup are also found in at least one other supergroup. The gene distribution across lineages thus reflects the presence of anaerobic energy metabolism in the eukaryote common ancestor and differential loss during the specialization of some lineages to oxic niches, just as oxphos capabilities have been differentially lost in specialization to anoxic niches and the parasitic life-style. Some facultative anaerobes have retained both aerobic and anaerobic pathways. Diversified eukaryotic lineages have retained the same enzymes of anaerobic ATP synthesis, in line with geochemical data indicating low environmental oxygen levels while eukaryotes arose and diversified.
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Affiliation(s)
| | - Marek Mentel
- Department of Biochemistry, Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia
| | - Jaap J. van Hellemond
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Katrin Henze
- Institute of Molecular Evolution, University of Düsseldorf, Düsseldorf, Germany
| | - Christian Woehle
- Institute of Molecular Evolution, University of Düsseldorf, Düsseldorf, Germany
| | - Sven B. Gould
- Institute of Molecular Evolution, University of Düsseldorf, Düsseldorf, Germany
| | - Re-Young Yu
- Institute of Molecular Evolution, University of Düsseldorf, Düsseldorf, Germany
| | - Mark van der Giezen
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Aloysius G. M. Tielens
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center, Rotterdam, Netherlands
| | - William F. Martin
- Institute of Molecular Evolution, University of Düsseldorf, Düsseldorf, Germany
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18
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Kawabe S, Yokoyama Y. Role of hypoxia-inducible factor α in response to hypoxia and heat shock in the Pacific oyster Crassostrea gigas. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2012; 14:106-119. [PMID: 21748344 DOI: 10.1007/s10126-011-9394-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Accepted: 06/02/2011] [Indexed: 05/31/2023]
Abstract
The Pacific oyster Crassostrea gigas inhabits the intertidal zone and shows tolerance to stress conditions such as hypoxia and heat shock. Although some information is available about the genes expressed in response to hypoxia, little is known about the molecular mechanism of the regulation of their expression in mollusks, including the Pacific oyster. Hypoxia-inducible factor 1α (HIF-1α) is a master regulator of hypoxia-responsive transcription. In this study, we cloned HIF-α from the oyster and investigated its response to unique stress conditions, including air exposure, for the first time in mollusks. The cDNA of oyster Hif-α is 3,182 bp long, of which 2,094 bp encodes a protein of 698 amino acid residues. Northern and Western blot analysis showed that expression of oyster HIF-α mRNA and protein were induced by air exposure, and that expression was induced periodically during air exposure. In addition, induction of Hif-α mRNA increased by a maximum 8.0-fold by heat shock. Under heat shock at 35°C (lethal temperature for the oyster), however, it was induced later than at 30°C. After recovery from hypoxia and/or heat shock, Hif-α mRNA also upregulated. These data suggest that the oyster has a strategy to induce Hif-α mRNA in order to survive hypoxia and heat shock, and that HIF signaling is necessary for recovery from stress.
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Affiliation(s)
- Shinya Kawabe
- Department of Marine Bioscience, Faculty of Marine Bioscience, Fukui Prefectural University, Obama, Fukui 917-0003, Japan
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19
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Birceanu O, McClelland GB, Wang YS, Brown JCL, Wilkie MP. The lampricide 3-trifluoromethyl-4-nitrophenol (TFM) uncouples mitochondrial oxidative phosphorylation in both sea lamprey (Petromyzon marinus) and TFM-tolerant rainbow trout (Oncorhynchus mykiss). Comp Biochem Physiol C Toxicol Pharmacol 2011; 153:342-9. [PMID: 21172453 DOI: 10.1016/j.cbpc.2010.12.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2010] [Revised: 12/09/2010] [Accepted: 12/09/2010] [Indexed: 11/17/2022]
Abstract
The toxicity of 3-trifluoromethyl-4-nitrophenol (TFM) appears to be due to a mismatch between ATP supply and demand in lamprey, depleting glycogen stores and starving the nervous system of ATP. The cause of this TFM-induced ATP deficit is unclear. One possibility is that TFM uncouples mitochondrial oxidative phosphorylation, thus impairing ATP production. To test this hypothesis, mitochondria were isolated from the livers of sea lamprey and rainbow trout, and O(2) consumption rates were measured in the presence of TFM or 2,4-dinitrophenol (2,4-DNP), a known uncoupler of oxidative phosphorylation. TFM and 2,4-DNP markedly increased State IV respiration in a dose-dependent fashion, but had no effect on State III respiration, which is consistent with uncoupling of oxidative phosphorylation. To determine how TFM uncoupled oxidative phosphorylation, the mitochondrial transmembrane potential (TMP) was recorded using the mitochondria-specific dye rhodamine 123. Mitochondrial TMP decreased by 22% in sea lamprey, and by 28% in trout following treatment with 50μmolL(-1) TFM. These findings suggest that TFM acted as a protonophore, dissipating the proton motive force needed to drive ATP synthesis. We conclude that the mode of TFM toxicity in sea lamprey and rainbow trout is via uncoupling of oxidative phosphorylation, leading to impaired ATP production.
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Affiliation(s)
- Oana Birceanu
- Department of Biology, Wilfrid Laurier University, 75 University Avenue W, Waterloo, Ontario, Canada N2L 3C5.
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20
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Kawabe S, Yokoyama Y. Molecular cloning of calnexin and calreticulin in the Pacific oyster Crassostrea gigas and its expression in response to air exposure. Mar Genomics 2010; 3:19-27. [PMID: 21798193 DOI: 10.1016/j.margen.2010.01.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2009] [Revised: 12/18/2009] [Accepted: 01/11/2010] [Indexed: 10/19/2022]
Abstract
Calnexin (CNX) and calreticulin (CRT) are endoplasmic reticulum (ER) chaperones. CNX is a type I transmembrane protein and CRT is a soluble CNX homologue. In the ER, CNX and CRT are important for Ca(2+) homeostasis and protein maturation. Here, we describe the full-length cDNA of the first mollusk CNX (cgCNX) and a second mollusk CRT (cgCRT) from the oyster Crassostrea gigas. CgCNX, containing 3255bp, was composed of a 1764bp open reading frame (ORF) that encodes a 588-amino acid protein. CgCRT, containing 1727bp, was composed of a 1242bp ORF that encodes a 414-amino acid protein. CgCNX and cgCRT contains an N-terminal 21- and 16-amino acid sequence, respectively, which is characteristic of a signal sequence. At the C-terminus, cgCRT also contains the KDEL (-Lys-Asp-Glu-Leu) peptide motif suggesting that cgCRT localizes in the ER. Northern blot analysis showed that both cgCNX and cgCRT mRNAs are induced by air exposure. The expression patterns of cgCNX mRNA differed from those of cgCRT during air exposure. This suggests that these two molecular chaperones have different roles in the response to air exposure.
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Affiliation(s)
- Shinya Kawabe
- Department of Marine Bioscience, Fukui Prefectural University, Obama, Japan
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Doucet-Beaupré H, Dubé C, Breton S, Pörtner HO, Blier PU. Thermal sensitivity of metabolic enzymes in subarctic and temperate freshwater mussels (Bivalvia: Unionoida). J Therm Biol 2010. [DOI: 10.1016/j.jtherbio.2009.10.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Tok CY, Chew SF, Peh WYX, Loong AM, Wong WP, Ip YK. Glutamine accumulation and up-regulation of glutamine synthetase activity in the swamp eel, Monopterus albus (Zuiew), exposed to brackish water. ACTA ACUST UNITED AC 2009; 212:1248-58. [PMID: 19376945 DOI: 10.1242/jeb.025395] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The swamp eel, Monopterus albus, is an air-breathing teleost which typically lives in freshwater but can also be found in estuaries, where it has to deal with ambient salinity fluctuations. Unlike other teleosts, its gills are highly degenerate. Hence, it may have uncommon osmoregulatory adaptations, but no information is available on its osmoregulatory capacity and mechanisms at present. In this study M. albus was exposed to a 5 day progressive increase in salinity from freshwater (1 per thousand) to brackish water (25 per thousand) and subsequently kept in 25 per thousand water for a total of 4 days. The results indicate that M. albus switched from hyperosmotic hyperionic regulation in freshwater to a combination of osmoconforming and hypoosmotic hypoionic regulation in 25 per thousand water. Exposure to 25 per thousand water resulted in relatively large increases in plasma osmolality, [Na(+)] and [Cl(-)]. Consequently, fish exposed to 25 per thousand water had to undergo cell volume regulation through accumulation of organic osmolytes and inorganic ions. Increases in tissue free amino acid content were apparently the result of increased protein degradation, decreased amino acid catabolism, and increased synthesis of certain non-essential amino acids. Here we report for the first time that glutamine is the major organic osmolyte in M. albus. Glutamine content increased to a phenomenal level of > 12 micromol g(-1) and > 30 micromol g(-1) in the muscle and liver, respectively, of fish exposed to 25 per thousand water. There were significant increases in glutamine synthetase (GS) activity in muscle and liver of these fish. In addition, exposure to 25 per thousand water for 4 days led to significant increases in GS protein abundance in both muscle and liver, indicating that increases in the expression of GS mRNA could have occurred.
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Affiliation(s)
- Chia Y Tok
- Department of Biological Sciences, National University of Singapore, Kent Ridge, Singapore 117543, Republic of Singapore
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