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Lian K, Hammarström D, Hamarsland H, Mølmen KS, Moen SC, Ellefsen S. Glucose ingestion before and after resistance training sessions does not augment ribosome biogenesis in healthy moderately trained young adults. Eur J Appl Physiol 2024:10.1007/s00421-024-05446-x. [PMID: 38459192 DOI: 10.1007/s00421-024-05446-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 02/09/2024] [Indexed: 03/10/2024]
Abstract
PURPOSE Resistance training-induced skeletal muscle hypertrophy seems to depend on ribosome biogenesis and content. High glucose treatment may augment ribosome biogenesis through potentiating resistance training-induced adaptations. This was investigated with total RNA and ribosomal RNA abundances as main outcomes, with relevant transcriptional/translational regulators (c-Myc/UBF/rpS6) as a secondary outcome. METHODS Sixteen healthy, moderately trained individuals [male/female, n = 9/7; age, 24.1 (3.3)] participated in a within-participant crossover trial with unilateral resistance training (leg press and knee extension, 3 sets of 10 repetitions maximum) and pre- and post-exercise ingestion of either glucose (3 × 30 g, 90 g total) or placebo supplements (Stevia rebaudiana, 3 × 0.3 g, 0.9 g total), together with protein (2 × 25 g, 50 g total), on alternating days for 12 days. Six morning resistance exercise sessions were conducted per condition, and the sessions were performed in an otherwise fasted state. Micro-biopsies were sampled from m. vastus lateralis before and after the intervention. RESULTS Glucose ingestion did not have beneficial effects on resistance training-induced increases of ribosomal content (mean difference 7.6% [- 7.2, 24.9], p = 0.34; ribosomal RNA, 47S/18S/28S/5.8S/5S, range 7.6-37.9%, p = 0.40-0.98) or levels of relevant transcriptional or translational regulators (c-MYK/UBF/rpS6, p = 0.094-0.292). Of note, both baseline and trained state data of total RNA showed a linear relationship with UBF; a ∼14% increase in total RNA corresponded to 1 SD unit increase in UBF (p = 0.003). CONCLUSION Glucose ingestion before and after resistance training sessions did not augment ribosomal RNA accumulation during twelve days of heavy-load resistance training in moderately trained young adults.
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Affiliation(s)
- Kristian Lian
- Section for Health and Exercise Physiology, Department of Public Health and Sport Sciences, Inland Norway University of Applied Sciences, Lillehammer, Norway.
| | - Daniel Hammarström
- Section for Health and Exercise Physiology, Department of Public Health and Sport Sciences, Inland Norway University of Applied Sciences, Lillehammer, Norway
| | - Håvard Hamarsland
- Section for Health and Exercise Physiology, Department of Public Health and Sport Sciences, Inland Norway University of Applied Sciences, Lillehammer, Norway
| | - Knut Sindre Mølmen
- Section for Health and Exercise Physiology, Department of Public Health and Sport Sciences, Inland Norway University of Applied Sciences, Lillehammer, Norway
| | - Sara Christine Moen
- Section for Health and Exercise Physiology, Department of Public Health and Sport Sciences, Inland Norway University of Applied Sciences, Lillehammer, Norway
| | - Stian Ellefsen
- Section for Health and Exercise Physiology, Department of Public Health and Sport Sciences, Inland Norway University of Applied Sciences, Lillehammer, Norway
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Gerber L, Resseguier J, Helle-Valle T, Farhat E, Nilsson GE, Lefevre S. Expression of prolyl hydroxylase domains, the upstream regulators of HIF, in the brain of the anoxia-tolerant crucian carp during anoxia-reoxygenation. Am J Physiol Regul Integr Comp Physiol 2024; 326:R184-R195. [PMID: 38145292 DOI: 10.1152/ajpregu.00211.2023] [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: 08/29/2023] [Revised: 11/10/2023] [Accepted: 12/11/2023] [Indexed: 12/26/2023]
Abstract
The hypoxia-inducible factor (HIF) is considered key in the transcriptional response to low oxygen. Yet, the role of HIF in the absence of oxygen (anoxia) and in preparation for reoxygenation remains unclear. Recent studies suggest that mounting a HIF response may be counterproductive for anoxia survival. We here studied one of the champions of anoxia survival, the crucian carp (Carassius carassius), and hypothesized that expression of prolyl hydroxylase domains (PHDs; the upstream regulators of HIF) are upregulated to circumvent an energy-costly activation of HIF in anoxia and to prepare for reoxygenation. We measured whole brain mRNA and protein levels of the three isoforms PHD1, PHD2, and PHD3, coded for by multiple paralogs of the genes egln2, egln1, and egln3, using quantitative PCR and Western blotting in the brain of crucian carps exposed to 5 days normoxia or anoxia, and 5 days anoxia followed by 3 or 24 h of reoxygenation. The mRNA levels of most egln paralogs were increased in anoxia and upon reoxygenation, with egln3 showing the largest increase in mRNA level (up to 17-fold) and highest relative mRNA abundance (up to 75% of expressed egln). The protein level of all PHDs was maintained in anoxia and increased upon reoxygenation. We then explored PHD distribution in different brain regions and found PHD immunoreactivity to be associated with axonal branches and showing region-specific changes during anoxia-reoxygenation. Our results support an overall upregulation of egln under prolonged anoxia and PHDs upon reoxygenation in crucian carp, likely aimed at suppressing HIF responses, although regional differences are apparent in such a complex organ as the brain.NEW & NOTEWORTHY We report a profound upregulation of most egln paralog mRNA levels in anoxia and upon reoxygenation, with egln3ii showing the largest, a 17-fold increase, and highest relative mRNA abundance. The relative abundance of prolyl hydroxylase domain (PHD) proteins was maintained during anoxia and increased at reoxygenation. PHD immunoreactivity was localized to axonal branches with region-specific changes during anoxia-reoxygenation. These dynamic and regional changes in crucian carp, champion of anoxia tolerance, are most likely adaptive and call for further mechanistic studies.
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Affiliation(s)
- Lucie Gerber
- Section for Physiology and Cell Biology, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Julien Resseguier
- Section for Physiology and Cell Biology, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Tellef Helle-Valle
- Section for Physiology and Cell Biology, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Elie Farhat
- Section for Physiology and Cell Biology, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Göran E Nilsson
- Section for Physiology and Cell Biology, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Sjannie Lefevre
- Section for Physiology and Cell Biology, Department of Biosciences, University of Oslo, Oslo, Norway
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Sparks K, Couturier CS, Buskirk J, Flores A, Hoeferle A, Hoffman J, Stecyk JAW. Gene expression of hypoxia-inducible factor (HIF), HIF regulators, and putative HIF targets in ventricle and telencephalon of Trachemys scripta acclimated to 21 °C or 5 °C and exposed to normoxia, anoxia or reoxygenation. Comp Biochem Physiol A Mol Integr Physiol 2022; 267:111167. [PMID: 35182763 PMCID: PMC8977064 DOI: 10.1016/j.cbpa.2022.111167] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Revised: 02/10/2022] [Accepted: 02/10/2022] [Indexed: 12/20/2022]
Abstract
In anoxia-sensitive mammals, hypoxia inducible factor (HIF) promotes cellular survival in hypoxia, but also tumorigenesis. By comparison, anoxia-tolerant vertebrates likely need to circumvent a prolonged upregulation of HIF to survive long-term anoxia, making them attractive biomedical models for investigating HIF regulation. To lend insight into the role of HIF in anoxic Trachemys scripta ventricle and telencephalon, 21 °C- and 5 °C-acclimated turtles were exposed to normoxia, anoxia (24 h at 21 °C; 24 h or 14 d at 5 °C) or anoxia + reoxygenation and the gene expression of HIF-1α (hif1a) and HIF-2α (hif2a), two regulators of HIF, and eleven putative downstream targets of HIF quantified by qPCR. Changes in gene expression with anoxia at 21 °C differentially aligned with a circumvention of HIF activity. Whereas hif1a and hif2a expression was unaffected in ventricle and telencephalon, and BCL2 interacting protein 3 gene expression reduced by 30% in telencephalon, gene expression of vascular endothelial growth factor-A increased in ventricle (4.5-fold) and telencephalon (1.5-fold), and hexokinase 1 (2-fold) and hexokinase 2 (3-fold) gene expression increased in ventricle. At 5 °C, the pattern of gene expression in ventricle or telencephalon was unaltered with oxygenation state. However, cold acclimation in normoxia induced downregulation of HIF-1α, HIF-2α, and HIF target gene expression in telencephalon. Overall, the findings lend support to the postulation that prolonged activation of HIF is counterproductive for long-term anoxia survival. Nevertheless, quantification of the effect of anoxia and acclimation temperature on HIF binding activity and regulation at the protein level are needed to provide a strong scientific framework whereby new strategies for oxygen related pathologies can be developed.
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Affiliation(s)
- Kenneth Sparks
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, United States
| | - Christine S Couturier
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, United States
| | - Jacob Buskirk
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, United States
| | - Alicia Flores
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, United States
| | - Aurora Hoeferle
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, United States
| | - Jessica Hoffman
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, United States
| | - Jonathan A W Stecyk
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, United States.
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Mølmen KS, Hammarström D, Pedersen K, Lian Lie AC, Steile RB, Nygaard H, Khan Y, Hamarsland H, Koll L, Hanestadhaugen M, Eriksen AL, Grindaker E, Whist JE, Buck D, Ahmad R, Strand TA, Rønnestad BR, Ellefsen S. Vitamin D 3 supplementation does not enhance the effects of resistance training in older adults. J Cachexia Sarcopenia Muscle 2021; 12:599-628. [PMID: 33788419 PMCID: PMC8200443 DOI: 10.1002/jcsm.12688] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 12/30/2020] [Accepted: 01/26/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Lifestyle therapy with resistance training is a potent measure to counteract age-related loss in muscle strength and mass. Unfortunately, many individuals fail to respond in the expected manner. This phenomenon is particularly common among older adults and those with chronic diseases (e.g. chronic obstructive pulmonary disease, COPD) and may involve endocrine variables such as vitamin D. At present, the effects of vitamin D supplementation on responses to resistance training remain largely unexplored. METHODS Ninety-five male and female participants (healthy, n = 71; COPD, n = 24; age 68 ± 5 years) were randomly assigned to receive either vitamin D3 or placebo supplementation for 28 weeks in a double-blinded manner (latitude 61°N, September-May). Seventy-eight participants completed the RCT, which was initiated by 12 weeks of supplementation-only (two weeks with 10 000 IU/day, followed by 2000 IU/day), followed by 13 weeks of combined supplementation (2000 IU/day) and supervised whole-body resistance training (twice weekly), interspersed with testing and measurements. Outcome measures included multiple assessments of muscle strength (nvariables = 7), endurance performance (n = 6), and muscle mass (n = 3, legs, primary), as well as muscle quality (legs), muscle biology (m. vastus lateralis; muscle fibre characteristics, transcriptome), and health-related variables (e.g. visceral fat mass and blood lipid profile). For main outcome domains such as muscle strength and muscle mass, weighted combined factors were calculated from the range of singular assessments. RESULTS Overall, 13 weeks of resistance training increased muscle strength (13% ± 8%), muscle mass (9% ± 8%), and endurance performance (one-legged, 23% ± 15%; whole-body, 8% ± 7%), assessed as weighted combined factors, and were associated with changes in health variables (e.g. visceral fat, -6% ± 21%; [LDL]serum , -4% ± 14%) and muscle tissue characteristics such as fibre type proportions (e.g. IIX, -3% points), myonuclei per fibre (30% ± 65%), total RNA/rRNA abundances (15%/6-19%), and transcriptome profiles (e.g. 312 differentially expressed genes). Vitamin D3 supplementation did not affect training-associated changes for any of the main outcome domains, despite robust increases in [25(OH)D]serum (∆49% vs. placebo). No conditional effects were observed for COPD vs. healthy or pre-RCT [25(OH)D]serum . In secondary analyses, vitamin D3 affected expression of gene sets involved in vascular functions in muscle tissue and strength gains in participants with high fat mass, which advocates further study. CONCLUSIONS Vitamin D3 supplementation did not affect muscular responses to resistance training in older adults with or without COPD.
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Affiliation(s)
- Knut Sindre Mølmen
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
| | - Daniel Hammarström
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
| | - Karianne Pedersen
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
| | - Anne Cecilie Lian Lie
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
| | - Ragnvald B. Steile
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
| | - Håvard Nygaard
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
| | - Yusuf Khan
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
- Department of BiotechnologyInland Norway University of Applied SciencesHamarNorway
| | - Håvard Hamarsland
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
| | - Lise Koll
- Innlandet Hospital TrustLillehammerNorway
| | | | | | - Eirik Grindaker
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
| | | | - Daniel Buck
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
| | - Rafi Ahmad
- Department of BiotechnologyInland Norway University of Applied SciencesHamarNorway
- Institute of Clinical Medicine, Faculty of Health SciencesUiT – The Arctic University of NorwayTromsøNorway
| | - Tor A. Strand
- Innlandet Hospital TrustLillehammerNorway
- Centre for International HealthUniversity of BergenBergenNorway
| | - Bent R. Rønnestad
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
| | - Stian Ellefsen
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
- Innlandet Hospital TrustLillehammerNorway
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Khan Y, Hammarström D, Rønnestad BR, Ellefsen S, Ahmad R. Increased biological relevance of transcriptome analyses in human skeletal muscle using a model-specific pipeline. BMC Bioinformatics 2020; 21:548. [PMID: 33256614 PMCID: PMC7708234 DOI: 10.1186/s12859-020-03866-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 11/09/2020] [Indexed: 12/12/2022] Open
Abstract
Background Human skeletal muscle responds to weight-bearing exercise with significant inter-individual differences. Investigation of transcriptome responses could improve our understanding of this variation. However, this requires bioinformatic pipelines to be established and evaluated in study-specific contexts. Skeletal muscle subjected to mechanical stress, such as through resistance training (RT), accumulates RNA due to increased ribosomal biogenesis. When a fixed amount of total-RNA is used for RNA-seq library preparations, mRNA counts are thus assessed in different amounts of tissue, potentially invalidating subsequent conclusions. The purpose of this study was to establish a bioinformatic pipeline specific for analysis of RNA-seq data from skeletal muscles, to explore the effects of different normalization strategies and to identify genes responding to RT in a volume-dependent manner (moderate vs. low volume). To this end, we analyzed RNA-seq data derived from a twelve-week RT intervention, wherein 25 participants performed both low- and moderate-volume leg RT, allocated to the two legs in a randomized manner. Bilateral muscle biopsies were sampled from m. vastus lateralis before and after the intervention, as well as before and after the fifth training session (Week 2). Result Bioinformatic tools were selected based on read quality, observed gene counts, methodological variation between paired observations, and correlations between mRNA abundance and protein expression of myosin heavy chain family proteins. Different normalization strategies were compared to account for global changes in RNA to tissue ratio. After accounting for the amounts of muscle tissue used in library preparation, global mRNA expression increased by 43–53%. At Week 2, this was accompanied by dose-dependent increases for 21 genes in rested-state muscle, most of which were related to the extracellular matrix. In contrast, at Week 12, no readily explainable dose-dependencies were observed. Instead, traditional normalization and non-normalized models resulted in counterintuitive reverse dose-dependency for many genes. Overall, training led to robust transcriptome changes, with the number of differentially expressed genes ranging from 603 to 5110, varying with time point and normalization strategy. Conclusion Optimized selection of bioinformatic tools increases the biological relevance of transcriptome analyses from resistance-trained skeletal muscle. Moreover, normalization procedures need to account for global changes in rRNA and mRNA abundance.
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Affiliation(s)
- Yusuf Khan
- Department of Biotechnology, Inland Norway University of Applied Sciences, Holsetgata 22, 2317, Hamar, Norway.,Section for Health and Exercise Physiology, Department of Public Health and Sport Sciences, Inland Norway University of Applied Sciences, Lillehammer, Norway
| | - Daniel Hammarström
- Section for Health and Exercise Physiology, Department of Public Health and Sport Sciences, Inland Norway University of Applied Sciences, Lillehammer, Norway.,Swedish School of Sport and Health Sciences, Stockholm, Sweden
| | - Bent R Rønnestad
- Section for Health and Exercise Physiology, Department of Public Health and Sport Sciences, Inland Norway University of Applied Sciences, Lillehammer, Norway
| | - Stian Ellefsen
- Section for Health and Exercise Physiology, Department of Public Health and Sport Sciences, Inland Norway University of Applied Sciences, Lillehammer, Norway.,Innlandet Hospital Trust, Lillehammer, Norway
| | - Rafi Ahmad
- Department of Biotechnology, Inland Norway University of Applied Sciences, Holsetgata 22, 2317, Hamar, Norway. .,Faculty of Health Sciences, Institute of Clinical Medicine, UiT - The Arctic University of Norway, Hansine Hansens veg 18, 9019, Tromsø, Norway.
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Stecyk JAW, Couturier CS, Abramochkin DV, Hall D, Arrant-Howell A, Kubly KL, Lockmann S, Logue K, Trueblood L, Swalling C, Pinard J, Vogt A. Cardiophysiological responses of the air-breathing Alaska blackfish to cold acclimation and chronic hypoxic submergence at 5°C. J Exp Biol 2020; 223:jeb225730. [PMID: 33020178 PMCID: PMC7687868 DOI: 10.1242/jeb.225730] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 09/28/2020] [Indexed: 01/29/2023]
Abstract
The Alaska blackfish (Dallia pectoralis) remains active at cold temperatures when experiencing aquatic hypoxia without air access. To discern the cardiophysiological adjustments that permit this behaviour, we quantified the effect of acclimation from 15°C to 5°C in normoxia (15N and 5N fish), as well as chronic hypoxic submergence (6-8 weeks; ∼6.3-8.4 kPa; no air access) at 5°C (5H fish), on in vivo and spontaneous heart rate (fH), electrocardiogram, ventricular action potential (AP) shape and duration (APD), the background inward rectifier (IK1) and rapid delayed rectifier (IKr) K+ currents and ventricular gene expression of proteins involved in excitation-contraction coupling. In vivo fH was ∼50% slower in 5N than in 15N fish, but 5H fish did not display hypoxic bradycardia. Atypically, cold acclimation in normoxia did not induce shortening of APD or alter resting membrane potential. Rather, QT interval and APD were ∼2.6-fold longer in 5N than in 15N fish because outward IK1 and IKr were not upregulated in 5N fish. By contrast, chronic hypoxic submergence elicited a shortening of QT interval and APD, driven by an upregulation of IKr The altered electrophysiology of 5H fish was accompanied by increased gene expression of kcnh6 (3.5-fold; Kv11.2 of IKr), kcnj12 (7.4-fold; Kir2.2 of IK1) and kcnj14 (2.9-fold; Kir2.4 of IK1). 5H fish also exhibited a unique gene expression pattern that suggests modification of ventricular Ca2+ cycling. Overall, the findings reveal that Alaska blackfish exposed to chronic hypoxic submergence prioritize the continuation of cardiac performance to support an active lifestyle over reducing cardiac ATP demand.
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Affiliation(s)
- Jonathan A W Stecyk
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, USA
| | - Christine S Couturier
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, USA
| | - Denis V Abramochkin
- Department of Human and Animal Physiology, Lomonosov Moscow State University, 1-12 Leninskiye Gory, 119991 Moscow, Russia
- Ural Federal University, 19 Mira Street, 620002 Ekaterinburg, Russia
- Laboratory of Cardiac Physiology, Institute of Physiology of Kоmi Science Centre of the Ural Branch of the Russian Academy of Sciences, FRC Komi SC UB RAS, 50 Pervomayskaya Str., 167982 Syktyvkar, Komi Republic, Russia
| | - Diarmid Hall
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, USA
| | - Asia Arrant-Howell
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, USA
| | - Kerry L Kubly
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, USA
| | - Shyanne Lockmann
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, USA
| | - Kyle Logue
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, USA
| | - Lenett Trueblood
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, USA
| | - Connor Swalling
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, USA
| | - Jessica Pinard
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, USA
| | - Angela Vogt
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, USA
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Sutcliffe RL, Li S, Gilbert MJH, Schulte PM, Miller KM, Farrell AP. A rapid intrinsic heart rate resetting response with thermal acclimation in rainbow trout, Oncorhynchus mykiss. J Exp Biol 2020; 223:jeb215210. [PMID: 32345705 PMCID: PMC7328139 DOI: 10.1242/jeb.215210] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Accepted: 04/17/2020] [Indexed: 01/01/2023]
Abstract
We examined cardiac pacemaker rate resetting in rainbow trout following a reciprocal temperature transfer. In the original experiment, performed in winter, 4°C-acclimated fish transferred to 12°C reset intrinsic heart rate after just 1 h (from 56.8±1.2 to 50.8±1.5 beats min-1); 12°C-acclimated fish transferred to 4°C reset intrinsic heart rate after 8 h (from 33.4±0.7 to 37.7±1.2 beats min-1). However, in a replicate experiment, performed in the summer using a different brood year, intrinsic heart rate was not reset, even after 10 weeks at a new temperature. Using this serendipitous opportunity, we compared mRNA expression changes of a suite of proteins in sinoatrial node (SAN), atrial and ventricular tissues after both 1 h and longer than 3 weeks for both experimental acclimation groups to identify those changes only associated with pacemaker rate resetting. Of the changes in mRNA expression occurring after more than 3 weeks of warm acclimation and associated with pacemaker rate resetting, we observed downregulation of NKA α1c in the atrium and ventricle, and upregulation of HCN1 in the ventricle. However, in the SAN there were no mRNA expression changes unique to the fish with pacemaker rate resetting after either 1 h or 3 weeks of warm acclimation. Thus, despite identifying changes in mRNA expression of contractile cardiac tissues, there was an absence of changes in mRNA expression directly involved with the initial, rapid pacemaker rate resetting with warm acclimation. Importantly, pacemaker rate resetting with thermal acclimation does not always occur in rainbow trout.
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Affiliation(s)
- Rachel L Sutcliffe
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
| | - Shaorong Li
- Pacific Biological Station, Fisheries and Oceans, Nanaimo, BC, Canada, V9T 6N7
| | - Matthew J H Gilbert
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
| | - Patricia M Schulte
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
| | - Kristi M Miller
- Pacific Biological Station, Fisheries and Oceans, Nanaimo, BC, Canada, V9T 6N7
| | - Anthony P Farrell
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
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Melleby AO, Sandvik GK, Couturier CS, Nilsson GE, Stecyk JAW. H 2S-producing enzymes in anoxia-tolerant vertebrates: Effects of cold acclimation, anoxia exposure and reoxygenation on gene and protein expression. Comp Biochem Physiol B Biochem Mol Biol 2020; 243-244:110430. [PMID: 32105700 DOI: 10.1016/j.cbpb.2020.110430] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 02/16/2020] [Accepted: 02/20/2020] [Indexed: 12/22/2022]
Abstract
To lend insight into the potential role of the gasotransmitter hydrogen sulfide (H2S) in facilitating anoxia survival of anoxia-tolerant vertebrates, we quantified the gene expression of the primary H2S-synthesizing enzymes, 3-mercaptopyruvate sulfurtransferase (3MST), cystathionine γ-lyase (CSE) and cystathionine β-synthase (CBS), in ventricle and brain of normoxic, anoxic and reoxygenated 21 °C- and 5 °C-acclimated freshwater turtles (Trachemys scripta) and 10 °C-acclimated crucian carp (Carassius carassius). Semi-quantitative Western blotting analysis was also conducted to assess 3MST and CBS protein abundance in ventricle and brain of 5 °C turtles and 10 °C crucian carp subjected to normoxia, anoxia and reoxygenation. We hypothesized that if H2S was advantageous for anoxia survival, expression levels would remain unchanged or be upregulated with anoxia and/or reoxygenation. Indeed, for both species, gene and protein expression were largely maintained with anoxia exposure (24 h, 21 °C; 5 d, 10 °C; 14 d, 5 °C). With reoxygenation, 3MST expression was increased in turtle and crucian carp brain at the protein and gene level, respectively. Additionally, the effect of cold acclimation on gene expression was assessed in several tissues of the turtle. Expression levels were maintained in most tissues, but decreased in others. The maintenance of gene and protein expression of the H2S-producing enzymes with anoxia exposure and the up-regulation of 3MST with reoxygenation suggests that H2S may facilitate anoxic survival of the two champions of vertebrate anoxia survival. The differential effects of cold acclimation on H2S enzyme expression may influence blood flow to different tissues during winter anoxia.
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Affiliation(s)
- Arne O Melleby
- Section for Physiology and Cell Biology, Department of Biosciences, University of Oslo, Oslo, Norway; Institute for Experimental Medical Research, University of Oslo, Oslo, Norway
| | - Guro K Sandvik
- Section for Physiology and Cell Biology, Department of Biosciences, University of Oslo, Oslo, Norway; Faculty of Biosciences, Norwegian University of Life Sciences, Ås, Norway
| | - Christine S Couturier
- Section for Physiology and Cell Biology, Department of Biosciences, University of Oslo, Oslo, Norway; Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK, United States
| | - Göran E Nilsson
- Section for Physiology and Cell Biology, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Jonathan A W Stecyk
- Section for Physiology and Cell Biology, Department of Biosciences, University of Oslo, Oslo, Norway; Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK, United States.
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Hammarström D, Øfsteng S, Koll L, Hanestadhaugen M, Hollan I, Apró W, Whist JE, Blomstrand E, Rønnestad BR, Ellefsen S. Benefits of higher resistance-training volume are related to ribosome biogenesis. J Physiol 2020; 598:543-565. [PMID: 31813190 DOI: 10.1113/jp278455] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 12/03/2019] [Indexed: 12/25/2022] Open
Abstract
KEY POINTS For individuals showing suboptimal adaptations to resistance training, manipulation of training volume is a potential measure to facilitate responses. This remains unexplored. Here, 34 untrained individuals performed contralateral resistance training with moderate and low volume for 12 weeks. Moderate volume led to larger increases in muscle cross-sectional area, strength and type II fibre-type transitions. These changes coincided with greater activation of signalling pathways controlling muscle growth and greater induction of ribosome synthesis. Out of 34 participants, thirteen displayed clear benefit of MOD on muscle hypertrophy and sixteen showed clear benefit of MOD on muscle strength gains. This coincided with greater total RNA accumulation in the early phase of the training period, suggesting that ribosomal biogenesis regulates the dose-response relationship between training volume and muscle hypertrophy. These results demonstrate that there is a dose-dependent relationship between training volume and outcomes. On the individual level, benefits of higher training volume were associated with increased ribosomal biogenesis. ABSTRACT Resistance-exercise volume is a determinant of training outcomes. However not all individuals respond in a dose-dependent fashion. In this study, 34 healthy individuals (males n = 16, 23.6 (4.1) years; females n = 18, 22.0 (1.3) years) performed moderate- (3 sets per exercise, MOD) and low-volume (1 set, LOW) resistance training in a contralateral fashion for 12 weeks (2-3 sessions per week). Muscle cross-sectional area (CSA) and strength were assessed at Weeks 0 and 12, along with biopsy sampling (m. vastus lateralis). Muscle biopsies were also sampled before and 1 h after the fifth session (Week 2). MOD resulted in larger increases in muscle CSA (5.2 (3.8)% versus 3.7 (3.7)%, P < 0.001) and strength (3.4-7.7% difference, all P < 0.05. This coincided with greater reductions in type IIX fibres from Week 0 to Week 12 (MOD, -4.6 percentage points; LOW -3.2 percentage points), greater phosphorylation of S6-kinase 1 (p85 S6K1Thr412 , 19%; p70 S6K1Thr389 , 58%) and ribosomal protein S6Ser235/236 (37%), greater rested-state total RNA (8.8%) and greater exercise-induced c-Myc mRNA expression (25%; Week 2, all P < 0.05). Thirteen and sixteen participants, respectively, displayed clear benefits in response to MOD on muscle hypertrophy and strength. Benefits were associated with greater accumulation of total RNA at Week 2 in the MOD leg, with every 1% difference increasing the odds of MOD benefit by 7.0% (P = 0.005) and 9.8% (P = 0.002). In conclusion, MOD led to greater functional and biological adaptations than LOW. Associations between dose-dependent total RNA accumulation and increases in muscle mass and strength point to ribosome biogenesis as a determinant of dose-dependent training responses.
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Affiliation(s)
- Daniel Hammarström
- Section for Health and Exercise Physiology, Department of Public Health and Sport Sciences, Inland Norway University of Applied Sciences, Elverum, Norway.,Swedish School of Sport and Health Sciences, Box 5626, SE-114 86, Stockholm, Sweden
| | - Sjur Øfsteng
- Section for Health and Exercise Physiology, Department of Public Health and Sport Sciences, Inland Norway University of Applied Sciences, Elverum, Norway
| | - Lise Koll
- Innlandet Hospital Trust, Postboks 990, 2629, Lillehammer, Norway
| | | | - Ivana Hollan
- Hospital for Rheumatic Diseases, Magrethe Grundtvigsvei 6, 2609, Lillehammer, Norway.,Brigham and Women's Hospital, 75 Francis Street, Boston, MA, 02115, USA
| | - William Apró
- Swedish School of Sport and Health Sciences, Box 5626, SE-114 86, Stockholm, Sweden
| | - Jon Elling Whist
- Innlandet Hospital Trust, Postboks 990, 2629, Lillehammer, Norway
| | - Eva Blomstrand
- Swedish School of Sport and Health Sciences, Box 5626, SE-114 86, Stockholm, Sweden
| | - Bent R Rønnestad
- Section for Health and Exercise Physiology, Department of Public Health and Sport Sciences, Inland Norway University of Applied Sciences, Elverum, Norway
| | - Stian Ellefsen
- Section for Health and Exercise Physiology, Department of Public Health and Sport Sciences, Inland Norway University of Applied Sciences, Elverum, Norway.,Innlandet Hospital Trust, Postboks 990, 2629, Lillehammer, Norway
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10
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The expression of genes involved in excitatory and inhibitory neurotransmission in turtle (Trachemys scripta) brain during anoxic submergence at 21 °C and 5 °C reveals the importance of cold as a preparatory cue for anoxia survival. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2019; 30:55-70. [DOI: 10.1016/j.cbd.2018.12.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Accepted: 12/27/2018] [Indexed: 11/20/2022]
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11
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Thomsen MT, Lefevre S, Nilsson GE, Wang T, Bayley M. Effects of lactate ions on the cardiorespiratory system in rainbow trout ( Oncorhynchus mykiss). Am J Physiol Regul Integr Comp Physiol 2019; 316:R607-R620. [PMID: 30811217 DOI: 10.1152/ajpregu.00395.2018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Lactate ions are involved in several physiological processes, including a direct stimulation of the carotid body, causing increased ventilation in mammals. A similar mechanism eliciting ventilatory stimulation in other vertebrate classes has been demonstrated, but it remains to be thoroughly investigated. Here, we investigated the effects of lactate ions on the cardiorespiratory system in swimming rainbow trout by manipulating the blood lactate concentration. Lactate elicited a vigorous, dose-dependent elevation of ventilation and bradycardia at physiologically relevant concentrations at constant pH. After this initial confirmation, we examined the chiral specificity of the response and found that only l-lactate induced these effects. By removal of the afferent inputs from the first gill arch, the response was greatly attenuated, and a comparison of the responses to injections up- and downstream of the gills collectively demonstrated that the lactate response was initiated by branchial cells. Injection of specific receptor antagonists revealed that a blockade of serotonergic receptors, which are involved in the hypoxic ventilatory response, significantly reduced the lactate response. Finally, we identified two putative lactate receptors based on sequence homology and found that both were expressed at substantially higher levels in the gills. We propose that lactate ions modulate ventilation by stimulating branchial oxygen-sensing cells, thus eliciting a cardiorespiratory response through receptors likely to have originated early in vertebrate evolution.
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Affiliation(s)
- Mikkel T Thomsen
- Department of Bioscience, Zoophysiology, Aarhus University , Aarhus , Denmark
| | - Sjannie Lefevre
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo , Oslo , Norway
| | - Göran E Nilsson
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo , Oslo , Norway
| | - Tobias Wang
- Department of Bioscience, Zoophysiology, Aarhus University , Aarhus , Denmark.,Aarhus Institute of Advanced Studies, Aarhus University , Aarhus , Denmark
| | - Mark Bayley
- Department of Bioscience, Zoophysiology, Aarhus University , Aarhus , Denmark
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12
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Baysa A, Fedorov A, Kondratov K, Ruusalepp A, Minasian S, Galagudza M, Popov M, Kurapeev D, Yakovlev A, Valen G, Kostareva A, Vaage J, Stensløkken KO. Release of Mitochondrial and Nuclear DNA During On-Pump Heart Surgery: Kinetics and Relation to Extracellular Vesicles. J Cardiovasc Transl Res 2018; 12:184-192. [PMID: 30542983 DOI: 10.1007/s12265-018-9848-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 11/18/2018] [Indexed: 12/12/2022]
Abstract
During heart surgery with cardiopulmonary bypass (CPB), the release of mitochondrial (mtDNA) and nuclear DNA (nDNA) and their association to extracellular vesicles were investigated. In patients undergoing elective coronary artery bypass grafting (CABG, n = 12), blood was sampled before, during, and after surgery from peripheral artery, pulmonary artery, and the coronary sinus. Plasma was separated in three fractions: microvesicles, exosomes, and supernatant. mtDNA and nDNA were measured by qPCR. mtDNA and nDNA levels increased after start of surgery, but before CPB, and increased further during CPB. mtDNA copy number was about 1000-fold higher than nDNA. mtDNA was predominantly localized to the vesicular fractions in plasma, whereas nDNA was predominantly in the supernatant. The amount of free mtDNA increased after surgery. There was no net release or disappearance of DNAs across the pulmonary, systemic, or coronary circulation. Extracellular DNAs, in particular mtDNA, may be important contributors to the whole-body inflammation during CPB.
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Affiliation(s)
- Anton Baysa
- Division of Physiology, Department of Molecular Medicine, Institute of Basic Medical Science, University of Oslo, Postbox 1103, Blindern, 0317, Oslo, Norway
- Center for Heart Failure Research, University of Oslo, Oslo, Norway
| | - Anton Fedorov
- Almazov National Medical Research Centre, Saint Petersburg, Russia
- Department of Cytology and Histology, Saint Petersburg State University, Saint Petersburg, Russia
| | - Kirill Kondratov
- Almazov National Medical Research Centre, Saint Petersburg, Russia
| | - Arno Ruusalepp
- Department of Cardiac Surgery, Tartu University Hospital, Tartu, Estonia
| | - Sarkis Minasian
- Almazov National Medical Research Centre, Saint Petersburg, Russia
| | | | - Maxim Popov
- Almazov National Medical Research Centre, Saint Petersburg, Russia
| | - Dmitry Kurapeev
- Almazov National Medical Research Centre, Saint Petersburg, Russia
| | - Alexey Yakovlev
- Almazov National Medical Research Centre, Saint Petersburg, Russia
| | - Guro Valen
- Division of Physiology, Department of Molecular Medicine, Institute of Basic Medical Science, University of Oslo, Postbox 1103, Blindern, 0317, Oslo, Norway
- Center for Heart Failure Research, University of Oslo, Oslo, Norway
| | - Anna Kostareva
- Almazov National Medical Research Centre, Saint Petersburg, Russia
| | - Jarle Vaage
- Institute of Clinical Medicine, Oslo University Hospital, University of Oslo, Oslo, Norway
| | - Kåre-Olav Stensløkken
- Division of Physiology, Department of Molecular Medicine, Institute of Basic Medical Science, University of Oslo, Postbox 1103, Blindern, 0317, Oslo, Norway.
- Center for Heart Failure Research, University of Oslo, Oslo, Norway.
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13
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Lawrence SD, Novak NG. The remarkable plethora of infestation-responsive Q-type C2H2 transcription factors in potato. BMC Res Notes 2018; 11:398. [PMID: 29921330 PMCID: PMC6011193 DOI: 10.1186/s13104-018-3503-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2018] [Accepted: 06/12/2018] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVE Q-type C2H2 transcription factors (TF) play crucial roles in the plant response to stress, often leading to regulation of downstream genes required for tolerance to these challenges. An infestation-responsive Q-type C2H2 TF (StZFP2) is induced by wounding and infestation in potato. While mining the Solanum tuberosum Group Phureja genome for additional members of this family of proteins, five StZFP2-like genes were found on a portion of chromosome 11. The objective of this work was to differentiate these genes in tissue specificity and expression upon infestation. RESULTS Examination of different tissues showed that young roots had the highest amounts of transcripts for five of the genes. Expression of their transcripts upon excision or infestation by Manduca sexta, showed that all six genes were induced. Overall, each gene showed variations in its response to infestation and specificity for tissue expression. The six genes encode very similar proteins but most likely play unique roles in the plant response to infestation. In contrast, only two homologs have been identified in Arabidopsis and tomato. Overexpression of similar genes has led to enhanced tolerance to, for example, salinity, drought and pathogen stress. Discovery of these new StZFP2 homologs could provide additional resources for potato breeders.
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Affiliation(s)
- Susan D. Lawrence
- Invasive Insect Biocontrol and Behavior Lab, USDA-ARS, 10300 Baltimore Ave., BARC-West Bldg 007, Rm 301, Beltsville, MD 20705 USA
| | - Nicole G. Novak
- Invasive Insect Biocontrol and Behavior Lab, USDA-ARS, 10300 Baltimore Ave., BARC-West Bldg 007, Rm 301, Beltsville, MD 20705 USA
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14
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Lefevre S, Stecyk JAW, Torp MK, Løvold LY, Sørensen C, Johansen IB, Stensløkken KO, Couturier CS, Sloman KA, Nilsson GE. Re-oxygenation after anoxia induces brain cell death and memory loss in the anoxia-tolerant crucian carp. ACTA ACUST UNITED AC 2018; 220:3883-3895. [PMID: 29093186 DOI: 10.1242/jeb.165118] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Accepted: 09/01/2017] [Indexed: 01/15/2023]
Abstract
Crucian carp (Carassius carassius) survive without oxygen for several months, but it is unknown whether they are able to protect themselves from cell death normally caused by the absence, and particularly return, of oxygen. Here, we quantified cell death in brain tissue from crucian carp exposed to anoxia and re-oxygenation using the terminal deoxy-nucleotidyl transferase dUTP nick-end labelling (TUNEL) assay, and cell proliferation by immunohistochemical staining for proliferating cell nuclear antigen (PCNA) as well as PCNA mRNA expression. We also measured mRNA and protein expression of the apoptosis executer protease caspase 3, in laboratory fish exposed to anoxia and re-oxygenation and fish exposed to seasonal anoxia and re-oxygenation in their natural habitat over the year. Finally, a behavioural experiment was used to assess the ability to learn and remember how to navigate in a maze to find food, before and after exposure to anoxia and re-oxygenation. The number of TUNEL-positive cells in the telencephalon increased after 1 day of re-oxygenation following 7 days of anoxia, indicating increased cell death. However, there were no consistent changes in whole-brain expression of caspase 3 in either laboratory-exposed or naturally exposed fish, indicating that cell death might occur via caspase-independent pathways or necrosis. Re-oxygenated crucian carp appeared to have lost the memory of how to navigate in a maze (learnt prior to anoxia exposure), while the ability to learn remained intact. PCNA mRNA was elevated after re-oxygenation, indicating increased neurogenesis. We conclude that anoxia tolerance involves not only protection from damage but also repair after re-oxygenation.
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Affiliation(s)
- Sjannie Lefevre
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, 0371 Oslo, Norway
| | - Jonathan A W Stecyk
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, 0371 Oslo, Norway
| | - May-Kristin Torp
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, 0371 Oslo, Norway
| | - Lisa Y Løvold
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, 0371 Oslo, Norway
| | - Christina Sørensen
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, 0371 Oslo, Norway
| | - Ida B Johansen
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, 0371 Oslo, Norway
| | - Kåre-Olav Stensløkken
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, 0371 Oslo, Norway
| | - Christine S Couturier
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, 0371 Oslo, Norway
| | - Katherine A Sloman
- Institute of Biomedical and Environmental Health Research, School of Science and Sport, University of the West of Scotland, PA1 2BE, UK
| | - Göran E Nilsson
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, 0371 Oslo, Norway
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15
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Fagernes CE, Stensløkken KO, Røhr ÅK, Berenbrink M, Ellefsen S, Nilsson GE. Extreme anoxia tolerance in crucian carp and goldfish through neofunctionalization of duplicated genes creating a new ethanol-producing pyruvate decarboxylase pathway. Sci Rep 2017; 7:7884. [PMID: 28801642 PMCID: PMC5554223 DOI: 10.1038/s41598-017-07385-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 06/23/2017] [Indexed: 11/09/2022] Open
Abstract
Without oxygen, most vertebrates die within minutes as they cannot meet cellular energy demands with anaerobic metabolism. However, fish of the genus Carassius (crucian carp and goldfish) have evolved a specialized metabolic system that allows them to survive prolonged periods without oxygen by producing ethanol as their metabolic end-product. Here we show that this has been made possible by the evolution of a pyruvate decarboxylase, analogous to that in brewer's yeast and the first described in vertebrates, in addition to a specialized alcohol dehydrogenase. Whole-genome duplication events have provided additional gene copies of the pyruvate dehydrogenase multienzyme complex that have evolved into a pyruvate decarboxylase, while other copies retained the essential function of the parent enzymes. We reveal the key molecular substitution in duplicated pyruvate dehydrogenase genes that underpins one of the most extreme hypoxic survival strategies among vertebrates and that is highly deleterious in humans.
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Affiliation(s)
| | - Kåre-Olav Stensløkken
- Institute of Basic Medical Sciences, University of Oslo, N-0372, Oslo, Norway.,Center for Heart Failure Research, University of Oslo, N-0317, Oslo, Norway
| | - Åsmund K Røhr
- Department of Biosciences, University of Oslo, N-0316, Oslo, Norway
| | - Michael Berenbrink
- Institute of Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, United Kingdom
| | - Stian Ellefsen
- The Lillehammer Research Center for Medicine and Exercise Physiology, Inland Norway University of Applied Sciences, N-2604, Lillehammer, Norway
| | - Göran E Nilsson
- Department of Biosciences, University of Oslo, N-0316, Oslo, Norway.
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16
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Cumming KT, Ellefsen S, Rønnestad BR, Ugelstad I, Raastad T. Acute and long-term effects of blood flow restricted training on heat shock proteins and endogenous antioxidant systems. Scand J Med Sci Sports 2016; 27:1190-1201. [DOI: 10.1111/sms.12774] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/19/2016] [Indexed: 01/01/2023]
Affiliation(s)
- K. T. Cumming
- Department of Physical Performance; Norwegian School of Sport Sciences; Oslo Norway
| | - S. Ellefsen
- Lillehammer University College; Lillehammer Norway
- Innlandet Hospital Trust; Brumunddal Norway
| | | | - I. Ugelstad
- Department of Physical Performance; Norwegian School of Sport Sciences; Oslo Norway
| | - T. Raastad
- Department of Physical Performance; Norwegian School of Sport Sciences; Oslo Norway
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17
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Eftestøl E, Egner IM, Lunde IG, Ellefsen S, Andersen T, Sjåland C, Gundersen K, Bruusgaard JC. Increased hypertrophic response with increased mechanical load in skeletal muscles receiving identical activity patterns. Am J Physiol Cell Physiol 2016; 311:C616-C629. [PMID: 27488660 DOI: 10.1152/ajpcell.00016.2016] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 07/26/2016] [Indexed: 11/22/2022]
Abstract
It is often assumed that mechanical factors are important for effects of exercise on muscle, but during voluntary training and most experimental conditions the effects could solely be attributed to differences in electrical activity, and direct evidence for a mechanosensory pathway has been scarce. We here show that, in rat muscles stimulated in vivo under deep anesthesia with identical electrical activity patterns, isometric contractions induced twofold more hypertrophy than contractions with 50-60% of the isometric force. The number of myonuclei and the RNA levels of myogenin and myogenic regulatory factor 4 were increased with high load, suggesting that activation of satellite cells is mechano dependent. On the other hand, training induced a major shift in fiber type distribution from type 2b to 2x that was load independent, indicating that the electrical signaling rather than mechanosignaling controls fiber type. RAC-α serine/threonine-protein kinase (Akt) and ribosomal protein S6 kinase β-1 (S6K1) were not significantly differentially activated by load, suggesting that the differences in mechanical factors were not important for activating the Akt/mammalian target of rapamycin/S6K1 pathway. The transmembrane molecule syndecan-4 implied in overload hypertrophy in cardiac muscle was not load dependent, suggesting that mechanosignaling in skeletal muscle is different.
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Affiliation(s)
- Einar Eftestøl
- Department of Biosciences, University of Oslo, Oslo, Norway
| | - Ingrid M Egner
- Department of Biosciences, University of Oslo, Oslo, Norway
| | - Ida G Lunde
- Department of Genetics, Harvard Medical School, Boston, Massachusetts; Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway; KG Jebsen Cardiac Research Center and Center for Heart Failure Research, University of Oslo, Oslo, Norway
| | - Stian Ellefsen
- Section for Sport Sciences, Lillehammer University College, Lillehammer, Norway; and
| | - Tom Andersen
- Department of Biosciences, University of Oslo, Oslo, Norway
| | | | | | - Jo C Bruusgaard
- Department of Biosciences, University of Oslo, Oslo, Norway; Department of Health Sciences, Kristiania University College, Oslo, Norway
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18
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Varis J, Haverinen J, Vornanen M. Lowering Temperature is the Trigger for Glycogen Build-Up and Winter Fasting in Crucian Carp (Carassius carassius). Zoolog Sci 2016; 33:83-91. [PMID: 26853873 DOI: 10.2108/zs150072] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Seasonal changes in physiology of vertebrate animals are triggered by environmental cues including temperature, day-length and oxygen availability. Crucian carp (Carassius carassius) tolerate prolonged anoxia in winter by using several physiological adaptations that are seasonally activated. This study examines which environmental cues are required to trigger physiological adjustments for winter dormancy in crucian carp. To this end, crucian carp were exposed to changing environmental factors under laboratory conditions: effects of declining water temperature, shortening day-length and reduced oxygen availability, separately and in different combinations, were examined on glycogen content and enzyme activities involved in feeding (alkaline phosphatase, AP) and glycogen metabolism (glycogen synthase, GyS; glycogen phosphorylase, GP). Lowering temperature induced a fall in activity of AP and a rise in glycogen content and rate of glycogen synthesis. Relative mass of the liver, and glycogen concentration of liver, muscle and brain increased with lowering temperature. Similarly activity of GyS in muscle and expression of GyS transcripts in brain were up-regulated by lowering temperature. Shortened day-length and oxygen availability had practically no effects on measured variables. We conclude that lowering temperature is the main trigger in preparation for winter anoxia in crucian carp.
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Affiliation(s)
- Joonas Varis
- Department of Biology, University of Eastern Finland, Yliopistokatu 7, 80101 Joensuu, Natura-building, Finland
| | - Jaakko Haverinen
- Department of Biology, University of Eastern Finland, Yliopistokatu 7, 80101 Joensuu, Natura-building, Finland
| | - Matti Vornanen
- Department of Biology, University of Eastern Finland, Yliopistokatu 7, 80101 Joensuu, Natura-building, Finland
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19
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Cristóbal HA, Poma HR, Abate CM, Rajal VB. Quantification of the Genetic Expression of bgl-A, bgl, and CspA and Enzymatic Characterization of β-Glucosidases from Shewanella sp. G5. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2016; 18:396-408. [PMID: 27164864 DOI: 10.1007/s10126-016-9702-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 03/26/2016] [Indexed: 06/05/2023]
Abstract
Shewanella sp. G5, a psychrotolerant marine bacterium, has a cold-shock protein (CspA) and three β-glucosidases, two of which were classified in the glycosyl hydrolase families 1 and 3 and are encoded by bgl-A and bgl genes, respectively. Shewanella sp. G5 was cultured on Luria-Bertani (LB) and Mineral Medium Brunner (MMB) media with glucose and cellobiose at various temperatures and pH 6 and 8. Relative quantification of the expression levels of all three genes was studied by real-time PCR with the comparative Ct method (2(-ΔΔCt)) using the gyrB housekeeping gene as a normalizer. Results showed that the genes had remarkably different genetic expression levels under the conditions evaluated, with increased expression of all genes obtained on MMB with cellobiose at 30 °C. Specific growth rate and specific β-glucosidase activity were also determined for all the culture conditions. Shewanella sp. G5 was able to grow on both media at 4 °C, showing the maximum specific growth rate on LB with cellobiose at 37 °C. The specific β-glucosidase activity obtained on MMB with cellobiose at 30 °C was 25 to 50 % higher than for all other conditions. At pH 8, relative activity was 34, 60, and 63 % higher at 30 °C than at 10 °C, with three peaks at 10, 25, and 37 °C on both media. Enzyme activity increased by 61 and 47 % in the presence of Ca(2+) and by 24 and 31 % in the presence of Mg(2+) on LB and MMB at 30 °C, respectively, but it was totally inhibited by Hg(2+), Cu(2+), and EDTA. Moreover, this activity was slightly decreased by SDS, Zn(2+), and DTT, all at 5 mM. Ethanol (14 % v/v) and glucose (100 mM) also reduced the activity by 63 and 60 %, respectively.
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Affiliation(s)
- Héctor Antonio Cristóbal
- Instituto de Investigaciones para la Industria Química, Universidad Nacional de Salta (INIQUI - CONICET-UNSa), Av. Bolivia 5150, 4400, Salta, Argentina.
- Planta Piloto de Procesos Industriales y Microbiológicos (PROIMI - CONICET), Av. Belgrano y Pje. Caseros, 4000, Tucumán, Argentina.
| | - Hugo Ramiro Poma
- Instituto de Investigaciones para la Industria Química, Universidad Nacional de Salta (INIQUI - CONICET-UNSa), Av. Bolivia 5150, 4400, Salta, Argentina
| | - Carlos Mauricio Abate
- Instituto de Investigaciones para la Industria Química, Universidad Nacional de Salta (INIQUI - CONICET-UNSa), Av. Bolivia 5150, 4400, Salta, Argentina
| | - Verónica Beatriz Rajal
- Instituto de Investigaciones para la Industria Química, Universidad Nacional de Salta (INIQUI - CONICET-UNSa), Av. Bolivia 5150, 4400, Salta, Argentina
- Facultad de Ingeniería, Universidad Nacional de Salta, Avda. Bolivia 5150, 4400, Salta, Argentina
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20
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Valbonesi P, Franzellitti S, Bersani F, Contin A, Fabbri E. Activity and expression of acetylcholinesterase in PC12 cells exposed to intermittent 1.8 GHz 217-GSM mobile phone signal. Int J Radiat Biol 2015; 92:1-10. [PMID: 26630175 DOI: 10.3109/09553002.2016.1114188] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE Due to its role in learning, memory and in many neurodegenerative diseases, acetylcholinesterase (AChE) represents an interesting endpoint to assess possible targets of exposure to radiofrequency electromagnetic fields (RF-EMF) generated by mobile phones. We investigated possible alterations of enzymatic activity, gene and protein expression of AChE in neuronal-like cells exposed to a 1.8 GHz Global System for Mobile Communication (GSM) modulated signal (217-GSM). MATERIALS AND METHODS Rat PC12 cells were exposed for 24 h to 1.8 GHz 217-GSM signal. Specific adsorption rate (SAR) was 2 W/kg. AChE enzyme activity was assessed spectrophotometrically by Ellman's method, mRNA expression level was evaluated by real time polymerase chain reaction, and protein expression was assessed by Western blotting. RESULTS AChE enzymatic activity increased of 1.4-fold in PC12 cells exposed to 217-GSM signal for 24 h, whilst AChE transcriptional or translational pathways were not affected. CONCLUSION Our results provide the first evidence of effects on AChE activity after in vitro exposure of mammalian cells to the RF-EMF generated by GSM mobile phones, at the SAR value 2 W/kg. The obtained evidence promotes further investigations on AChE as a possible target of RF-EMF and confirm the ability of 1.8 GHz 217-GSM signal to induce biological effects in different mammalian cells.
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Affiliation(s)
- Paola Valbonesi
- a Interdepartmental Centre for Environmental Science Research, University of Bologna , Campus of Ravenna , Italy ;,b Department of Biological, Geological and Environmental Sciences , University of Bologna , Bologna , Italy
| | - Silvia Franzellitti
- a Interdepartmental Centre for Environmental Science Research, University of Bologna , Campus of Ravenna , Italy ;,b Department of Biological, Geological and Environmental Sciences , University of Bologna , Bologna , Italy
| | | | - Andrea Contin
- a Interdepartmental Centre for Environmental Science Research, University of Bologna , Campus of Ravenna , Italy ;,c Department of Physics , University of Bologna , Bologna , Italy
| | - Elena Fabbri
- a Interdepartmental Centre for Environmental Science Research, University of Bologna , Campus of Ravenna , Italy ;,b Department of Biological, Geological and Environmental Sciences , University of Bologna , Bologna , Italy
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21
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Liu Q, Jones CS, Parsons AJ, Xue H, Rasmussen S. Does gibberellin biosynthesis play a critical role in the growth of Lolium perenne? Evidence from a transcriptional analysis of gibberellin and carbohydrate metabolic genes after defoliation. FRONTIERS IN PLANT SCIENCE 2015; 6:944. [PMID: 26579182 PMCID: PMC4630572 DOI: 10.3389/fpls.2015.00944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 10/17/2015] [Indexed: 05/08/2023]
Abstract
Global meat and milk production depends to a large extent on grazed pastures, with Lolium perenne being the major forage grass in temperate regions. Defoliation and subsequent regrowth of leaf blades is a major and essential event with respect to L. perenne growth and productivity. Following defoliation, carbohydrates (mainly fructans and sucrose) have to be mobilized from heterotrophic tissues to provide energy and carbon for regrowth of photosynthetic tissues. This mobilization of reserve carbohydrates requires a substantial change in the expression of genes coding for enzymes involved in carbohydrate metabolism. Here we tested the hypothesis that gibberellins (GA) are at the core of the processes regulating the expression of these genes. Thus, we examined the transcript profiles of genes involved in carbohydrate and GA metabolic pathways across a time course regrowth experiment. Our results show that following defoliation, the immediate reduction of carbohydrate concentrations in growing tissues is associated with a concomitant increase in the expression of genes encoding carbohydrate mobilizing invertases, and was also associated with a strong decrease in the expression of fructan synthesizing fructosyltransferase genes. We also show that the decrease in fructan levels is preceded by increased expression of the GA activating gene GA 3-oxidase and decreased expression of the GA inactivating gene GA 2 -oxidase in sheaths. GA 3-oxidase expression was negatively, while GA 2 -oxidase positively linked to sucrose concentrations. This study provides indicative evidence that gibberellins might play a role in L. perenne regrowth following defoliation and we hypothesize that there is a link between gibberellin regulation and sugar metabolism in L. perenne.
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Affiliation(s)
- Qianhe Liu
- Forage Improvement, Grasslands Institute, AgResearch Ltd.Palmerston North, New Zealand
| | - Chris S. Jones
- Forage Improvement, Grasslands Institute, AgResearch Ltd.Palmerston North, New Zealand
| | - Anthony J. Parsons
- Institute of Agriculture and Environment, Massey UniversityPalmerston North, New Zealand
| | - Hong Xue
- Forage Improvement, Grasslands Institute, AgResearch Ltd.Palmerston North, New Zealand
| | - Susanne Rasmussen
- Forage Improvement, Grasslands Institute, AgResearch Ltd.Palmerston North, New Zealand
- Institute of Agriculture and Environment, Massey UniversityPalmerston North, New Zealand
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22
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Ellefsen S, Hammarström D, Strand TA, Zacharoff E, Whist JE, Rauk I, Nygaard H, Vegge G, Hanestadhaugen M, Wernbom M, Cumming KT, Rønning R, Raastad T, Rønnestad BR. Blood flow-restricted strength training displays high functional and biological efficacy in women: a within-subject comparison with high-load strength training. Am J Physiol Regul Integr Comp Physiol 2015; 309:R767-79. [PMID: 26202071 PMCID: PMC4666930 DOI: 10.1152/ajpregu.00497.2014] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 07/20/2015] [Indexed: 12/12/2022]
Abstract
Limited data exist on the efficacy of low-load blood flow-restricted strength training (BFR), as compared directly to heavy-load strength training (HST). Here, we show that 12 wk of twice-a-week unilateral BFR [30% of one repetition maximum (1RM) to exhaustion] and HST (6-10RM) of knee extensors provide similar increases in 1RM knee extension and cross-sectional area of distal parts of musculus quadriceps femoris in nine untrained women (age 22 ± 1 yr). The two protocols resulted in similar acute increases in serum levels of human growth hormone. On the cellular level, 12 wk of BFR and HST resulted in similar shifts in muscle fiber composition in musculus vastus lateralis, evident as increased MyHC2A proportions and decreased MyHC2X proportions. They also resulted in similar changes of the expression of 29 genes involved in skeletal muscle function, measured both in a rested state following 12 wk of training and subsequent to singular training sessions. Training had no effect on myonuclei proportions. Of particular interest, 1) gross adaptations to BFR and HST were greater in individuals with higher proportions of type 2 fibers, 2) both BFR and HST resulted in approximately four-fold increases in the expression of the novel exercise-responsive gene Syndecan-4, and 3) BFR provided lesser hypertrophy than HST in the proximal half of musculus quadriceps femoris and also in CSApeak, potentially being a consequence of pressure from the tourniquet utilized to achieve blood flow restriction. In conclusion, BFR and HST of knee extensors resulted in similar adaptations in functional, physiological, and cell biological parameters in untrained women.
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Affiliation(s)
| | | | | | | | - Jon E Whist
- Innlandet Hospital Trust, Lillehammer, Norway
| | - Irene Rauk
- Innlandet Hospital Trust, Lillehammer, Norway
| | | | - Geir Vegge
- Lillehammer University College, Lillehammer, Norway
| | | | - Mathias Wernbom
- Lundberg Laboratory for Orthopaedic Research, Department of Orthopedics, The Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden; and Center for Health and Performance, Department of Food and Nutrition and Sport Science, University of Gothenburg, Gothenburg, Sweden
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23
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Taylor DA, Nair SV, Thompson EL, Raftos DA. Dose-dependent effects of metals on gene expression in the sydney rock oyster, Saccostrea glomerata. ENVIRONMENTAL TOXICOLOGY 2015; 30:989-998. [PMID: 24615909 DOI: 10.1002/tox.21972] [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: 07/17/2013] [Revised: 02/05/2014] [Accepted: 02/09/2014] [Indexed: 06/03/2023]
Abstract
In the current study, we tested the effects of common environmental contaminants (the metals zinc and lead) on gene expression in Sydney rock oysters (Saccrostrea glomerata). Oysters were exposed to a range of metal concentrations under controlled laboratory conditions. The expression of 14 putative stress response genes was then measured using quantitative, real-time (q) PCR. The expression of all 14 genes was significantly affected (p < 0.05 vs. nonexposed controls) by at least one of the metals, and by at least one dose of metal. For 5 of the 14 target genes (actin, calmodulin, superoxide dismutase, topoisomerase I, and tubulin) the alteration of expression relative to controls was highest at intermediate (rather than high) doses of metals. Such responses may reflect adaptive (acclimation) reactions in gene expression at low to intermediate doses of contaminants, followed by a decline in expression resulting from exposure at higher doses. The data are discussed in terms of the intracellular pathways affected by metal contamination, and the relevance of such gene expression data to environmental biomonitoring.
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Affiliation(s)
- Daisy A Taylor
- Department of Biological Sciences, Macquarie University, New South Wales, 2109, Australia
- Sydney Institute of Marine Science, Chowder Bay, New South Wale, 2088, Australia
| | - Sham V Nair
- Department of Biological Sciences, Macquarie University, New South Wales, 2109, Australia
| | - Emma L Thompson
- Department of Biological Sciences, Macquarie University, New South Wales, 2109, Australia
- Sydney Institute of Marine Science, Chowder Bay, New South Wale, 2088, Australia
| | - David A Raftos
- Department of Biological Sciences, Macquarie University, New South Wales, 2109, Australia
- Sydney Institute of Marine Science, Chowder Bay, New South Wale, 2088, Australia
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24
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Calusinska M, Hamilton C, Monsieurs P, Mathy G, Leys N, Franck F, Joris B, Thonart P, Hiligsmann S, Wilmotte A. Genome-wide transcriptional analysis suggests hydrogenase- and nitrogenase-mediated hydrogen production in Clostridium butyricum CWBI 1009. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:27. [PMID: 25722742 PMCID: PMC4342158 DOI: 10.1186/s13068-015-0203-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 01/12/2015] [Indexed: 05/21/2023]
Abstract
BACKGROUND Molecular hydrogen, given its pollution-free combustion, has great potential to replace fossil fuels in future transportation and energy production. However, current industrial hydrogen production processes, such as steam reforming of methane, contribute significantly to the greenhouse effect. Therefore alternative methods, in particular the use of fermentative microorganisms, have attracted scientific interest in recent years. However the low overall yield obtained is a major challenge in biological H2 production. Thus, a thorough and detailed understanding of the relationships between genome content, gene expression patterns, pathway utilisation and metabolite synthesis is required to optimise the yield of biohydrogen production pathways. RESULTS In this study transcriptomic and proteomic analyses of the hydrogen-producing bacterium Clostridium butyricum CWBI 1009 were carried out to provide a biomolecular overview of the changes that occur when the metabolism shifts to H2 production. The growth, H2-production, and glucose-fermentation profiles were monitored in 20 L batch bioreactors under unregulated-pH and fixed-pH conditions (pH 7.3 and 5.2). Conspicuous differences were observed in the bioreactor performances and cellular metabolisms for all the tested metabolites, and they were pH dependent. During unregulated-pH glucose fermentation increased H2 production was associated with concurrent strong up-regulation of the nitrogenase coding genes. However, no such concurrent up-regulation of the [FeFe] hydrogenase genes was observed. During the fixed pH 5.2 fermentation, by contrast, the expression levels for the [FeFe] hydrogenase coding genes were higher than during the unregulated-pH fermentation, while the nitrogenase transcripts were less abundant. The overall results suggest, for the first time, that environmental factors may determine whether H2 production in C. butyricum CWBI 1009 is mediated by the hydrogenases and/or the nitrogenase. CONCLUSIONS This work, contributing to the field of dark fermentative hydrogen production, provides a multidisciplinary approach for the investigation of the processes involved in the molecular H2 metabolism of clostridia. In addition, it lays the groundwork for further optimisation of biohydrogen production pathways based on genetic engineering techniques.
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Affiliation(s)
- Magdalena Calusinska
- />Centre for Protein Engineering, Bacterial Physiology and Genetics, University of Liège, Allée de la Chimie 3, B-4000 Liège, Belgium
- />Environmental Research and Innovation Department, Luxembourg Institute of Science and Technology, Rue du Brill 41, L-4422 Belvaux, Luxembourg
| | - Christopher Hamilton
- />Walloon Centre of Industrial Biology, University of Liège, Boulevard du Rectorat 29, B-4000 Liège, Belgium
| | - Pieter Monsieurs
- />Microbiology Unit, Expertise Group for Molecular and Cellular Biology, Institute for Environment, Health and Safety, Belgian Nuclear Research Centre (SCK-CEN), Boeretang 200, B-2400 Mol, Belgium
| | - Gregory Mathy
- />Bioenergetics Laboratory, University of Liège, Boulevard du Rectorat 27, B-4000 Liège, Belgium
| | - Natalie Leys
- />Microbiology Unit, Expertise Group for Molecular and Cellular Biology, Institute for Environment, Health and Safety, Belgian Nuclear Research Centre (SCK-CEN), Boeretang 200, B-2400 Mol, Belgium
| | - Fabrice Franck
- />Bioenergetics Laboratory, University of Liège, Boulevard du Rectorat 27, B-4000 Liège, Belgium
| | - Bernard Joris
- />Centre for Protein Engineering, Bacterial Physiology and Genetics, University of Liège, Allée de la Chimie 3, B-4000 Liège, Belgium
| | - Philippe Thonart
- />Walloon Centre of Industrial Biology, University of Liège, Boulevard du Rectorat 29, B-4000 Liège, Belgium
| | - Serge Hiligsmann
- />Walloon Centre of Industrial Biology, University of Liège, Boulevard du Rectorat 29, B-4000 Liège, Belgium
| | - Annick Wilmotte
- />Centre for Protein Engineering, Bacterial Physiology and Genetics, University of Liège, Allée de la Chimie 3, B-4000 Liège, Belgium
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25
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Stensløkken KO, Ellefsen S, Vasieva O, Fang Y, Farrell AP, Olohan L, Vaage J, Nilsson GE, Cossins AR. Life without oxygen: gene regulatory responses of the crucian carp (Carassius carassius) heart subjected to chronic anoxia. PLoS One 2014; 9:e109978. [PMID: 25372666 PMCID: PMC4220927 DOI: 10.1371/journal.pone.0109978] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Accepted: 09/09/2014] [Indexed: 11/19/2022] Open
Abstract
Crucian carp are unusual among vertebrates in surviving extended periods in the complete absence of molecular oxygen. During this time cardiac output is maintained though these mechanisms are not well understood. Using a high-density cDNA microarray, we have defined the genome-wide gene expression responses of cardiac tissue after exposing the fish at two temperatures (8 and 13°C) to one and seven days of anoxia, followed by seven days after restoration to normoxia. At 8°C, using a false discovery rate of 5%, neither anoxia nor re-oxygenation elicited appreciable changes in gene expression. By contrast, at 13°C, 777 unique genes responded strongly. Up-regulated genes included those involved in protein turnover, the pentose phosphate pathway and cell morphogenesis while down-regulated gene categories included RNA splicing and transcription. Most genes were affected between one and seven days of anoxia, indicating gene regulation over the medium term but with few early response genes. Re-oxygenation for 7 days was sufficient to completely reverse these responses. Glycolysis displayed more complex responses with anoxia up-regulated transcripts for the key regulatory enzymes, hexokinase and phosphofructokinase, but with down-regulation of most of the non-regulatory genes. This complex pattern of responses in genomic transcription patterns indicates divergent cardiac responses to anoxia, with the transcriptionally driven reprogramming of cardiac function seen at 13°C being largely completed at 8°C.
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Affiliation(s)
- Kåre-Olav Stensløkken
- Section for Physiology and Cell biology, Department of Biosciences, University of Oslo, Oslo, Norway
- Department of Physiology, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
- * E-mail:
| | - Stian Ellefsen
- Section for Sports Science, Department for Social Sciences, Lillehammer University College, Lillehammer, Norway
| | - Olga Vasieva
- Centre for Genomic Research, Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Yongxiang Fang
- Centre for Genomic Research, Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Anthony P. Farrell
- Department of Zoology, Faculty of Land and Food Systems, University of British Colombia, Vancouver, Canada
| | - Lisa Olohan
- Centre for Genomic Research, Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Jarle Vaage
- Department of Emergency Medicine and Intensive Care, Institute of Clinical Medicine, Oslo University Hospital Ullevål, Oslo, Norway
| | - Göran E. Nilsson
- Section for Physiology and Cell biology, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Andrew R. Cossins
- Centre for Genomic Research, Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
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26
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Irisin and FNDC5: effects of 12-week strength training, and relations to muscle phenotype and body mass composition in untrained women. Eur J Appl Physiol 2014; 114:1875-88. [PMID: 24906447 DOI: 10.1007/s00421-014-2922-x] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Accepted: 05/21/2014] [Indexed: 01/12/2023]
Abstract
PURPOSE To investigate the effects of strength training on abundances of irisin-related biomarkers in skeletal muscle and blood of untrained young women, and their associations with body mass composition, muscle phenotype and levels of thyroid hormones. METHODS Eighteen untrained women performed 12 weeks of progressive whole-body heavy strength training, with measurement of strength, body composition, expression of irisin-related genes (FNDC5 and PGC1α) in two different skeletal muscles, and levels of serum-irisin and -thyroid hormones, before and after the training intervention. RESULTS The strength training intervention did not result in changes in serum-irisin or muscle FNDC5 expression, despite considerable effects on strength, lean body mass (LBM) and skeletal muscle phenotype. Our data indicate that training affects irisin biology in a LBM-dependent manner. However, no association was found between steady-state serum-irisin or training-associated changes in serum-irisin and alterations in body composition. FNDC5 expression was higher in m.Biceps brachii than in m.Vastus lateralis, with individual expression levels being closely correlated, suggesting a systemic mode of transcriptional regulation. In pre-biopsies, FNDC5 expression was correlated with proportions of aerobic muscle fibers, a relationship that disappeared in post-biopsies. No association was found between serum-thyroid hormones and FNDC5 expression or serum-irisin. CONCLUSION No evidence was found for an effect of strength training on irisin biology in untrained women, though indications were found for a complex interrelationship between irisin, body mass composition and muscle phenotype. FNDC5 expression was closely associated with muscle fiber composition in untrained muscle.
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27
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Ellefsen S, Vikmoen O, Zacharoff E, Rauk I, Slettaløkken G, Hammarström D, Strand TA, Whist JE, Hanestadhaugen M, Vegge G, Fagernes CE, Nygaard H, Hollan I, Rønnestad BR. Reliable determination of training-induced alterations in muscle fiber composition in human skeletal muscle using quantitative polymerase chain reaction. Scand J Med Sci Sports 2014; 24:e332-42. [PMID: 24924099 DOI: 10.1111/sms.12185] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/06/2014] [Indexed: 12/14/2022]
Abstract
Determination of muscle fiber composition in human skeletal muscle biopsies is often performed using immunohistochemistry, a method that tends to be both time consuming, technically challenging, and complicated by limited availability of tissue. Here, we introduce quantitative reverse transcriptase polymerase chain reaction (qRT-PCR)-based Gene-family profiling (GeneFam) of myosin heavy chain (MyHC) mRNA expression as a high-throughput, sensitive, and reliable alternative. We show that GeneFam and immunohistochemistry result in similar disclosures of alterations in muscle fiber composition in biopsies from musculus vastus lateralis and musculus biceps brachii of previously untrained young women after 12 weeks of progressive strength training. The adaptations were evident as (a) consistent increases in MyHC2A abundance; (b) consistent decreases in MyHC2X abundance; and (c) consistently stable MyHC1 abundance, and were not found using traditional reference gene-based qRT-PCR analyses. Furthermore, muscle fiber composition found using each of the two approaches was correlated with each other (r = 0.50, 0.74, and 0.78 for MyHC1, A, and X, respectively), suggesting that GeneFam may be suitable for ranking of individual muscle phenotype, particularly for MyHC2 fibers. In summary, GeneFam of MyHC mRNA resulted in reliable assessment of alterations in muscle fiber composition in skeletal muscle of previously untrained women after 12 weeks of strength training.
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Affiliation(s)
- S Ellefsen
- Lillehammer University College, Lillehammer, Norway
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28
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Wilson CM, Stecyk JAW, Couturier CS, Nilsson GE, Farrell AP. Phylogeny and effects of anoxia on hyperpolarization-activated cyclic nucleotide-gated channel gene expression in the heart of a primitive chordate, the Pacific hagfish (Eptatretus stoutii). ACTA ACUST UNITED AC 2013; 216:4462-72. [PMID: 23997200 DOI: 10.1242/jeb.094912] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The aneural heart of the Pacific hagfish, Eptatretus stoutii, varies heart rate fourfold during recovery from anoxia. Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels, which play an important role in establishing the pacemaker rate of vertebrate hearts, were postulated to be present in this ancestral vertebrate heart, and it was also theorized that changes in hagfish heart rate with oxygen availability involved altered HCN expression. Partial gene cloning revealed six HCN isoforms in the hagfish heart. Hagfish representatives of HCN2, HCN3 and HCN4 were discovered, with HCN2 and HCN3 existing as isoforms designated as HCN2a, HCN2b, HCN3a, two paralogs of HCN3b, and HCN3c. Phylogenetic analysis revealed HCN3b and HCN3c to be ancestral, followed by HCN3a, HCN4 and HCN2. Moreover, HCN3a expression was dominant in both the atrial and ventricular chambers, suggesting that the HCN4 dominance in adult mammalian hearts appeared after hagfish divergence. HCN expression was higher in the atrium than in the ventricle, as might be expected given that atrial beating rate is known to be faster than the ventricular rate. In addition, mRNA expression under normoxic conditions was compared with that following 24 h of anoxia, and either a 2-h or 36-h recovery in normoxic water. In the ventricle, anoxia decreased HCN3a but not HCN4 expression. In contrast, atrial HCN3a expression significantly increased following 2 h of recovery, before returning to control levels following 36 h of recovery, possibly contributing to heart rate changes previously observed under these conditions.
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Affiliation(s)
- Christopher M Wilson
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
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29
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Taylor DA, Thompson EL, Nair SV, Raftos DA. Differential effects of metal contamination on the transcript expression of immune- and stress-response genes in the Sydney Rock oyster, Saccostrea glomerata. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2013; 178:65-71. [PMID: 23545341 DOI: 10.1016/j.envpol.2013.02.027] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Revised: 02/07/2013] [Accepted: 02/13/2013] [Indexed: 06/02/2023]
Abstract
Environmental contamination by metals is a serious threat to the biological sustainability of coastal ecosystems. Our current understanding of the potential biological effects of metals in these ecosystems is limited. This study tested the transcriptional expression of immune- and stress-response genes in Sydney Rock oysters (Saccostrea glomerata). Oysters were exposed to four metals (cadmium, copper, lead and zinc) commonly associated with anthropogenic pollution in coastal waterways. Seven target genes (superoxide dismutase, ferritin, ficolin, defensin, HSP70, HSP90 and metallothionein) were selected. Quantitative (real-time) PCR analyses of the transcript expression of these genes showed that each of the different metals elicited unique transcriptional profiles. Significant changes in transcription were found for 18 of the 28 combinations tested (4 metals × 7 genes). Of these, 16 reflected down-regulation of gene transcription. HSP90 was the only gene significantly up-regulated by metal contamination (cadmium and zinc only), while defensin expression was significantly down-regulated by exposure to all four metals. This inhibition could have a significant negative effect on the oyster immune system, promoting susceptibility to opportunistic infections and disease.
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Affiliation(s)
- Daisy A Taylor
- Sydney Institute of Marine Science, Chowder Bay, NSW 2088, Australia; Department of Biological Sciences, Macquarie University, NSW 2109, Australia
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30
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Cardiac KATP channel alterations associated with acclimation to hypoxia in goldfish (Carassius auratus L.). Comp Biochem Physiol A Mol Integr Physiol 2013; 164:554-64. [DOI: 10.1016/j.cbpa.2012.12.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 12/24/2012] [Accepted: 12/25/2012] [Indexed: 01/21/2023]
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Lanes C, Fernandes J, Kiron V, Babiak I. Profiling of key apoptotic, stress, and immune-related transcripts during embryonic and postembryonic development of Atlantic cod (Gadus morhua L.). Theriogenology 2012; 78:1583-1596.e2. [DOI: 10.1016/j.theriogenology.2012.07.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2012] [Revised: 07/05/2012] [Accepted: 07/05/2012] [Indexed: 12/13/2022]
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32
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Sandvik GK, Tomter AB, Bergan J, Zoppellaro G, Barra AL, Røhr AK, Kolberg M, Ellefsen S, Andersson KK, Nilsson GE. Studies of ribonucleotide reductase in crucian carp-an oxygen dependent enzyme in an anoxia tolerant vertebrate. PLoS One 2012; 7:e42784. [PMID: 22916159 PMCID: PMC3419237 DOI: 10.1371/journal.pone.0042784] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Accepted: 07/11/2012] [Indexed: 11/19/2022] Open
Abstract
The enzyme ribonucleotide reductase (RNR) catalyzes the conversion of ribonucleotides to deoxyribonucleotides, the precursors for DNA. RNR requires a thiyl radical to activate the substrate. In RNR of eukaryotes (class Ia RNR), this radical originates from a tyrosyl radical formed in reaction with oxygen (O(2)) and a ferrous di-iron center in RNR. The crucian carp (Carassius carassius) is one of very few vertebrates that can tolerate several months completely without oxygen (anoxia), a trait that enables this fish to survive under the ice in small ponds that become anoxic during the winter. Previous studies have found indications of cell division in this fish after 7 days of anoxia. This appears nearly impossible, as DNA synthesis requires the production of new deoxyribonucleotides and therefore active RNR. We have here characterized RNR in crucian carp, to search for adaptations to anoxia. We report the full-length sequences of two paralogs of each of the RNR subunits (R1i, R1ii, R2i, R2ii, p53R2i and p53R2ii), obtained by cloning and sequencing. The mRNA levels of these subunits were measured with quantitative PCR and were generally well maintained in hypoxia and anoxia in heart and brain. We also report maintained or increased mRNA levels of the cell division markers proliferating cell nuclear antigen (PCNA), brain derived neurotrophic factor (BDNF) and Ki67 in anoxic hearts and brains. Electron paramagnetic resonance (EPR) measurements on in vitro expressed crucian carp R2 and p53R2 proteins gave spectra similar to mammalian RNRs, including previously unpublished human and mouse p53R2 EPR spectra. However, the radicals in crucian carp RNR small subunits, especially in the p53R2ii subunit, were very stable at 0°C. A long half-life of the tyrosyl radical during wintertime anoxia could allow for continued cell division in crucian carp.
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Affiliation(s)
- Guro K Sandvik
- Department of Molecular Biosciences, University of Oslo, Oslo, Norway.
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33
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Ellefsen S, Bliksøen M, Rutkovskiy A, Johansen IB, Kaljusto ML, Nilsson GE, Vaage JI, Stensløkken KO. Per-unit-living tissue normalization of real-time RT-PCR data in ischemic rat hearts. Physiol Genomics 2012; 44:651-6. [PMID: 22535878 DOI: 10.1152/physiolgenomics.00004.2012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In studies of gene expression in acute ischemic heart tissue, internal reference genes need to show stable expression per-unit-living tissue to hinder dead cells from biasing real-time RT-PCR data. Until now, this important issue has not been appropriately investigated. We hypothesized that the expression of seven internal reference genes would show stable per-unit-living tissue expression in Langendorff-perfused rat hearts subjected to ischemia-reperfusion. This was found for cyclophilin A, GAPDH, RPL-32, and PolR2A mRNA, with GAPDH showing the highest degree of stability (R = 0.11), suggesting unchanged rates of mRNA transcription in live cells and complete degradation of mRNA from dead cells. The infarct size-dependent degradation of GAPDH was further supported by a close correlation between changes in GAPDH mRNA and changes in RNA quality measured as RNA integrity number (R = 0.90, P < 0.05). In contrast, β-actin and 18S rRNA showed stable expression per-unit-weight tissue and a positive correlation with infarct size (R = 0.61 and R = 0.77, P < 0.05 for both analyses). The amount of total RNA extracted per-unit-weight tissue did not differ between groups despite wide variation in infarct size (7.1-50.1%). When β-actin expression was assessed using four different normalization strategies, GAPDH and geNorm provided appropriate per-unit-living expression, while 18S and total RNA resulted in marked underestimations. In studies of ischemic tissues, we recommend using geometric averaging of carefully selected reference genes for normalization of real-time RT-PCR data. A marked shift in the mRNA/rRNA ratio renders rRNA as useless for normalization purposes.
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Affiliation(s)
- S Ellefsen
- Lillehammer University College, Lillehammer, Norway
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Sandvik GK, Nilsson GE, Jensen FB. Dramatic increase of nitrite levels in hearts of anoxia-exposed crucian carp supporting a role in cardioprotection. Am J Physiol Regul Integr Comp Physiol 2011; 302:R468-77. [PMID: 22129619 DOI: 10.1152/ajpregu.00538.2011] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Nitrite (NO(2)(-)) functions as an important nitric oxide (NO) donor under hypoxic conditions. Both nitrite and NO have been found to protect the mammalian heart and other tissues against ischemia (anoxia)-reoxygenation injury by interacting with mitochondrial electron transport complexes and limiting the generation of reactive oxygen species upon reoxygenation. The crucian carp naturally survives extended periods without oxygen in an active state, which has made it a model for studying how evolution has solved the problems of anoxic survival. We investigated the role of nitrite and NO in the anoxia tolerance of this fish by measuring NO metabolites in normoxic, anoxic, and reoxygenated crucian carp. We also cloned and sequenced crucian carp NO synthase variants and quantified their mRNA levels in several tissues in normoxia and anoxia. Despite falling levels of blood plasma nitrite, the crucian carp showed massive increases in nitrite, S-nitrosothiols (SNO), and iron-nitrosyl (FeNO) compounds in anoxic heart tissue. NO(2)(-) levels were maintained in anoxic brain, liver, and gill tissues, whereas SNO and FeNO increased in a tissue-specific manner. Reoxygenation reestablished normoxic values. We conclude that NO(2)(-) is shifted into the tissues where it acts as NO donor during anoxia, inducing cytoprotection under anoxia/reoxygenation. This can be especially important in the crucian carp heart, which maintains output in anoxia. NO(2)(-) is currently tested as a therapeutic drug against reperfusion damage of ischemic hearts, and the present study provides evolutionary precedent for such an approach.
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Affiliation(s)
- Guro K Sandvik
- Department of Molecular Biosciences, University of Oslo, Oslo, Norway.
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Stecyk JAW, Couturier CS, Fagernes CE, Ellefsen S, Nilsson GE. Quantification of heat shock protein mRNA expression in warm and cold anoxic turtles (Trachemys scripta) using an external RNA control for normalization. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2011; 7:59-72. [PMID: 22129782 DOI: 10.1016/j.cbd.2011.11.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2011] [Revised: 11/07/2011] [Accepted: 11/07/2011] [Indexed: 01/30/2023]
Abstract
The mRNA expression of heat-shock protein 90 (HSP90) and heat-shock cognate 70 (HSC70) was examined in cardiac chambers and telencephalon of warm- (21°C) and cold-acclimated (5°C) turtles (Trachemys scripta) exposed to normoxia, prolonged anoxia or anoxia followed by reoxygenation. Additionally, the suitability of total RNA as well as mRNA from β-actin, glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and cyclophilin A (PPIA) for normalizing gene expression data was assessed, as compared to the use of an external RNA control. Measurements of HSP90 and HSC70 mRNA expression revealed that anoxia and reoxygenation have tissue- and gene-specific effects. By and large, the alterations support previous investigations on HSP protein abundance in the anoxic turtle heart and brain, as well as the hypothesized roles of HSP90 and HSC70 during stress and non-stress conditions. However, more prominent was a substantially increased HSP90 and HSC70 mRNA expression in the cardiac chambers with cold acclimation. The finding provides support for the notion that cold temperature induces a number of adaptations in tissues of anoxia-tolerant vertebrates that precondition them for winter anoxia. β-actin, GAPDH and PPIA mRNA expression and total RNA also varied with oxygenation state and acclimation temperature in a tissue- and gene-specific manner, as well as among tissue types, thus disqualifying them as suitable for real-time RT-PCR normalization. Thus, the present data highlights the advantages of normalizing real-time RT-PCR data to an external RNA control, an approach that also allows inter-tissue and potentially inter-species comparisons of target gene expression.
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Affiliation(s)
- Jonathan A W Stecyk
- Physiology Programme, Department of Molecular Biosciences, University of Oslo, PO Box 1041, N-0316, Oslo, Norway.
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DAUGHERTY THF, TOTH AL, ROBINSON GE. Nutrition and division of labor: Effects on foraging and brain gene expression in the paper wasp Polistes metricus. Mol Ecol 2011; 20:5337-47. [DOI: 10.1111/j.1365-294x.2011.05344.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Nikinmaa M, Rytkönen KT. Functional genomics in aquatic toxicology-do not forget the function. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2011; 105:16-24. [PMID: 22099341 DOI: 10.1016/j.aquatox.2011.05.019] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Accepted: 05/28/2011] [Indexed: 05/31/2023]
Abstract
Toxicological responses of an organism are disturbances of function. This as a starting point we review and discuss issues that we consider important in applying functional genomics to aquatic toxicology. Functional genomics includes all the steps in gene expression pathway. Thus, ultimately the goal is to relate genome information to protein activity. In ecotoxicogenomics the toxicological responses must further be combined with responses to natural environmental changes. We focus on fish, but also consider commonly used invertebrates, mainly Daphnia. We first go through the toxicologically important features of genomes of aquatic animals, and then review the reference gene approach to quantify transcript amount. Thereafter we emphasize the need to relate the mRNA and protein levels, and protein activity of individual genes. Finally we discuss how functional genomic investigations may be important in resolving current environmental problems and give our views of valuable future research topics.
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O'Shaughnessy PJ, Monteiro A, Fowler PA. Identification of stable endogenous reference genes for real-time PCR in the human fetal gonad using an external standard technique. Mol Hum Reprod 2011; 17:620-5. [PMID: 21527436 DOI: 10.1093/molehr/gar032] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Measurement of tissue mRNA transcript levels is critically dependent upon the normalization strategy used. For real-time polymerase chain reaction (PCR) (RT-PCR) this commonly depends upon identification of stable (non-variable) endogenous reference genes, with housekeeping genes (HKGs) the most commonly used. In this report we describe the use of an external mRNA standard to identify stable HKGs in the human fetal gonad. Total RNA was extracted from second trimester human fetal gonads and a standard amount of luciferase mRNA was added at the start of the extraction process. Levels of luciferase were then measured relative to each of seven HKGs (SDHA, TBP, B2M, PMM1, SFRS4, HMBS and UBC) by RT-PCR. When normalized to tissue weight, HKG expression was constant across fetal ages. Measurement of overall variation in transcript expression showed that PMM1 was the most stable HKG in the ovary while B2M was most stable in the testis. Re-analysis of the data using GeNorm and NormFinder algorithms showed that two of the top three most stable HKGs were the same using all three methods. This study describes a method for identification of endogenous, stable reference genes for RT-PCR studies of transcript expression levels which is objective and not dependent on prior assumptions of HKG expression. This technique is likely to be applicable to most tissues and, in this case, identifies suitable HKGs for studies into human gonadal development.
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Affiliation(s)
- Peter J O'Shaughnessy
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, UK.
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Lunde IG, Anton SL, Bruusgaard JC, Rana ZA, Ellefsen S, Gundersen K. Hypoxia inducible factor 1 links fast-patterned muscle activity and fast muscle phenotype in rats. J Physiol 2011; 589:1443-54. [PMID: 21262877 DOI: 10.1113/jphysiol.2010.202762] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Exercise influences muscle phenotype by the specific pattern of action potentials delivered to the muscle, triggering intracellular signalling pathways. PO2 can be reduced by an order of magnitude in working muscle. In humans, carriers of a hyperactive polymorphism of the transcription factor hypoxia inducible factor 1α (HIF-1α) have 50% more fast fibres, and this polymorphism is prevalent among strength athletes. We have investigated the putative role of HIF-1α in mediating activity changes in muscle.When rat muscles were stimulated with short high frequency bursts of action potentials known to induce a fast muscle phenotype, HIF-1α increased by about 80%. In contrast, a pattern consisting of long low frequency trains known to make fast muscles slow reduced the HIF-1α level of the fast extensor digitorum longus (EDL) muscle by 44%. Nuclear protein extracts from normal EDL contained 2.3-fold more HIF-1α and 4-fold more HIF-1β than the slow soleus muscle, while von-Hippel-Lindau protein was 4.8-fold higher in slow muscles. mRNA displayed a reciprocal pattern; thus FIH-1 mRNA was almost 2-fold higher in fast muscle, while the HIF-1α level was half, and consequently protein/mRNA ratio for HIF-1α was more than 4-fold higher in the fast muscle, suggesting that HIF-1α is strongly suppressed post-transcriptionally in slow muscles.When HIF-1α was overexpressed for 14 days after somatic gene transfer in adult rats, a slow-to-fast transformation was observed, encompassing an increase in fibre cross sectional area, oxidative enzyme activity and myosin heavy chain. The latter was shown to be regulated at the mRNA level in C2C12 myotubes.
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Affiliation(s)
- Ida G Lunde
- Department of Molecular Biosciences, University of Oslo, PO Box 1041, Blindern, N-0316 Oslo, Norway
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DeCoste NJ, Gadkar VJ, Filion M. Relative and absolute quantitative real-time PCR-based quantifications of hcnC and phlD gene transcripts in natural soil spiked with Pseudomonas sp. strain LBUM300. Appl Environ Microbiol 2011; 77:41-7. [PMID: 21075889 PMCID: PMC3019740 DOI: 10.1128/aem.01387-10] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2010] [Accepted: 11/01/2010] [Indexed: 11/20/2022] Open
Abstract
Transcriptional analysis of microbial gene expression using relative quantitative real-time PCR (qRT-PCR) has been hampered by various technical problems. One such problem is the unavailability of an exogenous standard robust enough for use in a complex matrix like soil. To circumvent this technical issue, we made use of a recently developed artificial RNA (myIC) as an exogenous "spike-in" control. Nonsterile field soil was inoculated with various concentrations of the test bacterium Pseudomonas sp. strain LBUM300, ranging from 4.3- to 8.3-log bacterial cells per gram of soil. Total soil RNA was extracted at days 0, 7, and 14 postinoculation, and using two-step TaqMan assays, phlD (encoding the production of 2,4-diacetylphloroglucinol) and hcnC (encoding the production of hydrogen cyanide) gene expression was monitored. For relative quantification, a defined quantity of in vitro-synthesized myIC RNA was spiked during the RNA extraction procedure. Absolute qRT-PCR was also performed in parallel. Both the absolute and relative quantifications showed similar transcriptional trends. Overall, the transcriptional activity of phlD and hcnC changed over time and with respect to the bacterial concentrations used. Transcripts of the phlD and hcnC genes were detected for all five bacterial concentrations, but the phlD transcript copy numbers detected were lower than those detected for hcnC, regardless of the initial bacterial concentration or sampling date. For quantifying a low number of transcripts, the relative method was more reliable than the absolute method. This study demonstrates for the first time the use of a relative quantification approach to quantifying microbial gene transcripts from field soil using an exogenous spike-in control.
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Affiliation(s)
- Nadine J. DeCoste
- Université de Moncton, Department of Biology, 18 Antonine-Maillet, Moncton, NB E1A 3E9, Canada
| | - Vijay J. Gadkar
- Université de Moncton, Department of Biology, 18 Antonine-Maillet, Moncton, NB E1A 3E9, Canada
| | - Martin Filion
- Université de Moncton, Department of Biology, 18 Antonine-Maillet, Moncton, NB E1A 3E9, Canada
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Ma M, Liu LZ. Quantitative transcription dynamic analysis reveals candidate genes and key regulators for ethanol tolerance in Saccharomyces cerevisiae. BMC Microbiol 2010; 10:169. [PMID: 20537179 PMCID: PMC2903563 DOI: 10.1186/1471-2180-10-169] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2010] [Accepted: 06/10/2010] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Derived from our lignocellulosic conversion inhibitor-tolerant yeast, we generated an ethanol-tolerant strain Saccharomyces cerevisiae NRRL Y-50316 by enforced evolutionary adaptation. Using a newly developed robust mRNA reference and a master equation unifying gene expression data analyses, we investigated comparative quantitative transcription dynamics of 175 genes selected from previous studies for an ethanol-tolerant yeast and its closely related parental strain. RESULTS A highly fitted master equation was established and applied for quantitative gene expression analyses using pathway-based qRT-PCR array assays. The ethanol-tolerant Y-50316 displayed significantly enriched background of mRNA abundance for at least 35 genes without ethanol challenge compared with its parental strain Y-50049. Under the ethanol challenge, the tolerant Y-50316 responded in consistent expressions over time for numerous genes belonging to groups of heat shock proteins, trehalose metabolism, glycolysis, pentose phosphate pathway, fatty acid metabolism, amino acid biosynthesis, pleiotropic drug resistance gene family and transcription factors. The parental strain showed repressed expressions for many genes and was unable to withstand the ethanol stress and establish a viable culture and fermentation. The distinct expression dynamics between the two strains and their close association with cell growth, viability and ethanol fermentation profiles distinguished the tolerance-response from the stress-response in yeast under the ethanol challenge. At least 82 genes were identified as candidate and key genes for ethanol-tolerance and subsequent fermentation under the stress. Among which, 36 genes were newly recognized by the present study. Most of the ethanol-tolerance candidate genes were found to share protein binding motifs of transcription factors Msn4p/Msn2p, Yap1p, Hsf1p and Pdr1p/Pdr3p. CONCLUSION Enriched background of transcription abundance and enhanced expressions of ethanol-tolerance genes associated with heat shock proteins, trehalose-glycolysis-pentose phosphate pathways and PDR gene family are accountable for the tolerant yeast to withstand the ethanol stress, maintain active metabolisms, and complete ethanol fermentation under the ethanol stress. Transcription factor Msn4p appeared to be a key regulator of gene interactions for ethanol-tolerance in the tolerant yeast Y-50316.
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Affiliation(s)
- Menggen Ma
- Bioenergy Research, National Center for Agricultural Utilization Research USDA-ARS, Peoria, IL USA
- Department of Computer Science, New Mexico State University, Las Cruces, NM USA
| | - Lewis Z Liu
- Bioenergy Research, National Center for Agricultural Utilization Research USDA-ARS, Peoria, IL USA
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Stensløkken KO, Ellefsen S, Larsen HK, Vaage J, Nilsson GE. Expression of heat shock proteins in anoxic crucian carp (Carassius carassius): support for cold as a preparatory cue for anoxia. Am J Physiol Regul Integr Comp Physiol 2010; 298:R1499-508. [DOI: 10.1152/ajpregu.00675.2009] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The crucian carp ( Carassius carassius ) tolerates anoxia for days to months depending on temperature. During episodes of stress, heat shock proteins (HSPs) are important for limiting cellular damage, mainly by ensuring protein function. Accordingly, we hypothesized that anoxia would change the expression of HSPs and that this response would be temperature dependent. Real-time RT-PCR was used to investigate the effects of 1 and 7 days anoxia (A1 and A7) on the expression of HSP70a, HSP70b, HSC70, HSP90, and HSP30 in the brain and heart of 8°C- and 13°C-acclimated crucian carp. In general, the expression of all HSPs changed in response to anoxia, although varying in size and direction, and with organ and temperature. HSP70a expression increased drastically (∼10-fold) in A7 brains and hearts at 13°C but not at 8°C. HSC70 and HSP90 expression decreased in A7 brains (by 60–70%), but not in A7 hearts. HSC70 expression increased in A1 brains and hearts at both temperatures (by 60–160%), and HSP30 expression decreased in A7 brains and hearts at both temperatures (by 50–80%). Notably, normoxic fish showed 7- and 11-fold higher HSP70a expression in the brain and heart at 8°C compared with 13°C. This difference disappeared during anoxia, suggesting that cold may function as a cue for preconditioning the crucian carp's HSP70a expression to the approaching anoxic winter period.
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Affiliation(s)
- Kåre-Olav Stensløkken
- Department of Molecular Biosciences and
- Faculty Division Ullevål University Hospital, University of Oslo, Oslo, Norway; and
| | | | | | - Jarle Vaage
- Faculty Division Ullevål University Hospital, University of Oslo, Oslo, Norway; and
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Rytkönen KT, Renshaw GMC, Ashton KJ, Williams-Pritchard G, Leder EH, Nikinmaa M. Elasmobranch qPCR reference genes: a case study of hypoxia preconditioned epaulette sharks. BMC Mol Biol 2010; 11:27. [PMID: 20416043 PMCID: PMC2864272 DOI: 10.1186/1471-2199-11-27] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2009] [Accepted: 04/23/2010] [Indexed: 11/18/2022] Open
Abstract
Background Elasmobranch fishes are an ancient group of vertebrates which have high potential as model species for research into evolutionary physiology and genomics. However, no comparative studies have established suitable reference genes for quantitative PCR (qPCR) in elasmobranchs for any physiological conditions. Oxygen availability has been a major force shaping the physiological evolution of vertebrates, especially fishes. Here we examined the suitability of 9 reference candidates from various functional categories after a single hypoxic insult or after hypoxia preconditioning in epaulette shark (Hemiscyllium ocellatum). Results Epaulette sharks were caught and exposed to hypoxia. Tissues were collected from 10 controls, 10 individuals with single hypoxic insult and 10 individuals with hypoxia preconditioning (8 hypoxic insults, 12 hours apart). We produced sequence information for reference gene candidates and monitored mRNA expression levels in four tissues: cerebellum, heart, gill and eye. The stability of the genes was examined with analysis of variance, geNorm and NormFinder. The best ranking genes in our study were eukaryotic translation elongation factor 1 beta (eef1b), ubiquitin (ubq) and polymerase (RNA) II (DNA directed) polypeptide F (polr2f). The performance of the ribosomal protein L6 (rpl6) was tissue-dependent. Notably, in one tissue the analysis of variance indicated statistically significant differences between treatments for genes that were ranked as the most stable candidates by reference gene software. Conclusions Our results indicate that eef1b and ubq are generally the most suitable reference genes for the conditions and tissues in the present epaulette shark studies. These genes could also be potential reference gene candidates for other physiological studies examining stress in elasmobranchs. The results emphasise the importance of inter-group variation in reference gene evaluation.
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Affiliation(s)
- Kalle T Rytkönen
- Division of Genetics and Physiology, Department of Biology, University of Turku, FI-20014 Turku, Finland.
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Ellefsen S, Stensløkken KO. Gene-family profiling: a normalization-free real-time RT-PCR approach with increased physiological resolution. Physiol Genomics 2010; 42:1-4. [PMID: 20215416 DOI: 10.1152/physiolgenomics.00196.2009] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Here we present gene-family profiling, an approach for improved real-time RT-PCR analyses. It is based on recently published data, and we argue that it bring solutions to two major problems. First, it is normalization-free and therefore unbiased by variation in normalization agents such as reference gene expression. This strengthens data validity and also increases data resolution, reducing coefficients of variation by approximately 48% in our data sets. Second, it includes all members of a particular gene family, treating individual genes as constituting fractions of collective gene-family expression rather than as unrelated entities. Because different family members typically fulfill similar, but complementary roles, this increases the physiological relevance. Gene-family profiling is particularly useful for evaluation of cellular adaptations to physiological challenges and for comparison of properties between different experimental systems such as species, tissues or tissue regions. In addition, it seems suitable for analyses of inherent patterns of gene expression in singular biological samples. In our opinion, the approach is valuable for both research and diagnostic purposes, and should be readily applicable for many studies of gene expression. Its value is likely to increase as science continues to unravel gene function.
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No evidence for enhanced parvalbumin concentration in light muscle of transgenic coho salmon (Oncorhynchus kisutch). Eur Food Res Technol 2009. [DOI: 10.1007/s00217-009-1086-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Kitao Y, Kono T, Korenaga H, Iizasa T, Nakamura K, Savan R, Sakai M. Characterization and expression analysis of type I interferon in common carp Cyprinus carpio L. Mol Immunol 2009; 46:2548-56. [DOI: 10.1016/j.molimm.2009.05.012] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2009] [Revised: 05/12/2009] [Accepted: 05/14/2009] [Indexed: 11/28/2022]
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Ellefsen S, Stensløkken KO, Fagernes CE, Kristensen TA, Nilsson GE. Expression of genes involved in GABAergic neurotransmission in anoxic crucian carp brain (Carassius carassius). Physiol Genomics 2009; 36:61-8. [DOI: 10.1152/physiolgenomics.90301.2008] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The crucian carp, Carassius carassius, survives days to months without oxygen, depending on temperature. In the anoxic crucian carp brain, increased GABAergic inhibition, mediated by increased extracellular levels of GABA, has been shown to suppress electric activity and ATP consumption. To investigate an involvement of gene expression in this response, we utilized real-time RT-PCR to test the effect of 1 and 7 days anoxia (8°C) on the expression of 22 genes, including nine GABAAreceptor subunits (α1–6, β2, δ, and γ2), three GABABreceptor subunits (GB1a-1b and GB2), three enzymes involved in GABA metabolism (GAD65 and GAD67, GABAT), four GABA transporters (GAT1, 2a-b and 3), two GABAAreceptor-associated proteins (GABARAP 1 and 2), and the K+/Cl−cotransporter KCC2. While the expression of GABAAreceptor subunits was dominated by α4-, α6-, and δ-subunits, all of which are located to extrasynaptic sites in mammalian brains and respond to elevations in extracellular levels of GABA by showing tonic activity patterns, the expression of GABA transporters was dominated by GAT2 (a and b) and GAT3, which also show extrasynaptic location in mammals. These expression patterns differ from those observed in mammals and may be a prerequisite for GABAergic inhibition of anoxic metabolic rate in crucian carp. Furthermore, while the expression of the majority of the genes was largely unaltered by anoxia, the expression of GAT2 and GAT3 decreased to 20%. This suggests impairment of GABA transport, which could be a mechanism behind the accumulation of extracellular GABA and the increased GABAergic inhibition.
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Affiliation(s)
- Stian Ellefsen
- Physiology Programme, Department of Molecular Biosciences, University of Oslo, Oslo
- Lillehammer University College, Lillehammer
| | | | - Cathrine E. Fagernes
- Physiology Programme, Department of Molecular Biosciences, University of Oslo, Oslo
| | - Tom A. Kristensen
- Gene Programme, Department of Molecular Biosciences, University of Oslo, Oslo, Norway
| | - Göran E. Nilsson
- Physiology Programme, Department of Molecular Biosciences, University of Oslo, Oslo
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Stensløkken KO, Ellefsen S, Stecyk JAW, Dahl MB, Nilsson GE, Vaage J. Differential regulation of AMP-activated kinase and AKT kinase in response to oxygen availability in crucian carp (Carassius carassius). Am J Physiol Regul Integr Comp Physiol 2008; 295:R1803-14. [PMID: 18922957 DOI: 10.1152/ajpregu.90590.2008] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
We investigated whether two kinases critical for survival during periods of energy deficiency in anoxia-intolerant mammalian species, AMP-activated kinase (AMPK), and protein kinase B (AKT), are equally important for hypoxic/anoxic survival in the extremely anoxia-tolerant crucian carp (Carassius carassius). We report that phosphorylation of AMPK and AKT in heart and brain showed small changes after 10 days of severe hypoxia (0.3 mg O2/l at 9 degrees C). In contrast, anoxia exposure (0.01 mg O2/l at 8 degrees C) substantially increased AMPK phosphorylation but decreased AKT phosphorylation in carp heart and brain, indicating activation of AMPK and deactivation of AKT. In agreement, blocking the activity of AMPK in anoxic fish in vivo with 20 mg/kg Compound C resulted in an elevated metabolic rate (as indicated by increased ethanol production) and tended to reduce energy charge. This is the first in vivo experiment with Compound C in a nonmammalian vertebrate, and it appears that AMPK plays a role in mediating anoxic metabolic depression in crucian carp. Real-time RT-PCR analysis of the investigated AMPK subunit revealed that the most likely composition of subunits in the carp heart is alpha2, beta1B, gamma2a, whereas a more even expression of subunits was found in the brain. In the heart, expression of the regulatory gamma2-subunit increased in the heart during anoxia. In the brain, expression of the alpha1-, alpha2-, and gamma1-subunits decreased with anoxia exposure, but expression of the gamma2-subunit remained constant. Combined, our findings suggest that AMPK and AKT may play important, but opposing roles for hypoxic/anoxic survival in the anoxia-tolerant crucian carp.
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Ellefsen S, Sandvik GK, Larsen HK, Stensløkken KO, Hov DAS, Kristensen TA, Nilsson GE. Expression of genes involved in excitatory neurotransmission in anoxic crucian carp (Carassius carassius) brain. Physiol Genomics 2008; 35:5-17. [PMID: 18593861 DOI: 10.1152/physiolgenomics.90221.2008] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The crucian carp, Carassius carassius, survives months without oxygen. During anoxia it needs to keep energy expenditure low, particularly in the brain, with its high rate of ATP use related to neuronal activity. This could be accomplished by reducing neuronal excitability through altered expression of genes involved in excitatory neurotransmission. Through cloning and the use of a recently developed real-time RT-PCR approach, with an external RNA control for normalization, we investigated the effect of 1 and 7 days of anoxia (12 degrees C) on the expression of 29 genes, including 8 3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) receptor subunits, 6 N-methyl-d-aspartate (NMDA) receptor subunits, 7 voltage-gated sodium and calcium channels, 4 glutamate transporters, and 4 genes involved in NMDA receptor-mediated neuroplasticity. The subunits of the majority of the gene families had expression profiles similar to those observed in the mammalian brain and showed remarkably stable expression during anoxia. This suggests that the genes may have similar functions in crucian carp and mammals, and that the excitatory abilities of the crucian carp brain are retained during anoxia. Although the data generally argue against profound neural depression ("channel arrest"), NMDA receptor subunit (NR) expression showed features that could mediate reduced neural excitability. Primarily, the NR2 subunit expression, which was dominated by NR2B and NR2D, resembled that seen in hypoxia-tolerant neonatal rats, and decreased anoxic expression of NR1, NR2C, and NR3A indicated reduced numbers of functional NMDA receptors. We also report the full-length sequence of crucian carp NR1 mRNA and a novel NR1 splice cassette introducing an N-glycosylation site into the extracellular S1S2 domain.
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Affiliation(s)
- Stian Ellefsen
- Physiology Programme, Department of Molecular Biosciences, University of Oslo, Oslo.
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