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Akrokoh J, Bediako JO, Fafanyo K, Musah-Yussif H, Asubonteng AK, Adjei HO, Ofori AGA, Skov PV, Obirikorang KA. Relatedness of hypoxia and hyperthermia tolerances in the Nile tilapia (Oreochromis niloticus) and their relationships with cardiac and gill traits. Comp Biochem Physiol A Mol Integr Physiol 2024; 294:111648. [PMID: 38643961 DOI: 10.1016/j.cbpa.2024.111648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2024] [Revised: 04/18/2024] [Accepted: 04/18/2024] [Indexed: 04/23/2024]
Abstract
In fish, thermal and hypoxia tolerances may be functionally related, as suggested by the oxygen- and capacity-limited thermal tolerance (OCLTT) concept, which explains performance failure at high temperatures due to limitations in oxygen delivery. In this study the interrelatedness of hyperthermia and hypoxia tolerances in the Nile tilapia (Oreochromis niloticus), and their links to cardiorespiratory traits were examined. Different groups of O. niloticus (n = 51) were subjected to hypoxia and hyperthermia challenges and the O2 tension for aquatic surface respiration (ASR pO2) and critical thermal maximum (CTmax) were assessed as measurement endpoints. Gill filament length, total filament number, ventricle mass, length and width were also measured. Tolerance to hypoxia, as evidenced by ASR pO2 thresholds of the individual fish, was highly variable and varied between 0.26 and 3.39 kPa. ASR events increased more profoundly as O2 tensions decreased below 2 kPa. The CTmax values recorded for the O. niloticus individuals ranged from 43.1 to 44.8 °C (Mean: 44.2 ± 0.4 °C). Remarkably, there was a highly significant correlation between ASR pO2 and CTmax in O. niloticus (r = -0.76, p < 0.0001) with ASR pO2 increasing linearly with decreasing CTmax. There were, however, no discernible relationships between the measured cardiorespiratory properties and hypoxia or hyperthermia tolerances. The strong relationship between hypoxia and hyperthermia tolerances in this study may be related to the ability of the cardiorespiratory system to provide oxygen to respiring tissues under thermal stress, and thus provides some support for the OCLTT concept in this species, at least at the level of the entire organism.
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Affiliation(s)
- Jesslyn Akrokoh
- Department of Fisheries and Watershed Management, Faculty of Renewable Natural Resources, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana. https://twitter.com/@missakrokoh
| | - Jedida Osei Bediako
- Department of Fisheries and Watershed Management, Faculty of Renewable Natural Resources, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Kelvin Fafanyo
- Department of Fisheries and Watershed Management, Faculty of Renewable Natural Resources, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Harriya Musah-Yussif
- Department of Fisheries and Watershed Management, Faculty of Renewable Natural Resources, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Audrey Korsah Asubonteng
- Department of Fisheries and Watershed Management, Faculty of Renewable Natural Resources, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Henry Owusu Adjei
- Department of Fisheries and Watershed Management, Faculty of Renewable Natural Resources, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | | | - Peter Vilhelm Skov
- Technical University of Denmark, DTU Aqua, Section for Aquaculture, The North Sea Research Centre, DK-9850 Hirtshals, Denmark
| | - Kwasi Adu Obirikorang
- Department of Fisheries and Watershed Management, Faculty of Renewable Natural Resources, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana.
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Burggren W, Fahlman A, Milsom W. Breathing patterns and associated cardiovascular changes in intermittently breathing animals: (Partially) correcting a semantic quagmire. Exp Physiol 2024; 109:1051-1065. [PMID: 38502538 PMCID: PMC11215480 DOI: 10.1113/ep091784] [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: 01/23/2024] [Accepted: 02/29/2024] [Indexed: 03/21/2024]
Abstract
Many animal species do not breathe in a continuous, rhythmic fashion, but rather display a variety of breathing patterns characterized by prolonged periods between breaths (inter-breath intervals), during which the heart continues to beat. Examples of intermittent breathing abound across the animal kingdom, from crustaceans to cetaceans. With respect to human physiology, intermittent breathing-also termed 'periodic' or 'episodic' breathing-is associated with a variety of pathologies. Cardiovascular phenomena associated with intermittent breathing in diving species have been termed 'diving bradycardia', 'submersion bradycardia', 'immersion bradycardia', 'ventilation tachycardia', 'respiratory sinus arrhythmia' and so forth. An examination across the literature of terminology applied to these physiological phenomena indicates, unfortunately, no attempt at standardization. This might be viewed as an esoteric semantic problem except for the fact that many of the terms variously used by different authors carry with them implicit or explicit suggestions of underlying physiological mechanisms and even human-associated pathologies. In this article, we review several phenomena associated with diving and intermittent breathing, indicate the semantic issues arising from the use of each term, and make recommendations for best practice when applying specific terms to particular cardiorespiratory patterns. Ultimately, we emphasize that the biology-not the semantics-is what is important, but also stress that confusion surrounding underlying mechanisms can be avoided by more careful attention to terms describing physiological changes during intermittent breathing and diving.
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Affiliation(s)
- Warren Burggren
- Developmental Integrative Biology Group, Department of Biological SciencesUniversity of North TexasDentonTexasUSA
| | - Andreas Fahlman
- Fundación OceanogràficValenciaSpain
- Kolmården Wildlife ParkKolmårdenSweden
- IFMLinkoping UniversityLinkopingSweden
| | - William Milsom
- Department of ZoologyUniversity of British ColumbiaVancouverBritish ColumbiaCanada
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Chen J, Hu Z, Li P, Wang G, Wei H, Li Q, Fu B, Sun Y. Transcriptomic atlas for hypoxia and following re-oxygenation in Ancherythroculter nigrocauda heart and brain tissues: insights into gene expression, alternative splicing, and signaling pathways. Front Genet 2024; 15:1365285. [PMID: 38689653 PMCID: PMC11058841 DOI: 10.3389/fgene.2024.1365285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Accepted: 03/22/2024] [Indexed: 05/02/2024] Open
Abstract
Hypoxia is a mounting problem that affects the world's freshwaters, with severe consequence for many species, including death and large economical loss. The hypoxia problem has increased recently due to the combined effects of water eutrophication and global warming. In this study, we investigated the transcriptome atlas for the bony fish Ancherythroculter nigrocauda under hypoxia for 1.5, 3, and 4.5 h and its recovery to normal oxygen levels in heart and brain tissues. We sequenced 21 samples for brain and heart tissues (a total of 42 samples) plus three control samples and obtained an average of 32.40 million raw reads per sample, and 95.24% mapping rate of the filtered clean reads. This robust transcriptome dataset facilitated the discovery of 52,428 new transcripts and 6,609 novel genes. In the heart tissue, the KEGG enrichment analysis showed that genes linked to the Vascular smooth muscle contraction and MAPK and VEGF signaling pathways were notably altered under hypoxia. Re-oxygenation introduced changes in genes associated with abiotic stimulus response and stress regulation. In the heart tissue, weighted gene co-expression network analysis pinpointed a module enriched in insulin receptor pathways that was correlated with hypoxia. Conversely, in the brain tissue, the response to hypoxia was characterized by alterations in the PPAR signaling pathway, and re-oxygenation influenced the mTOR and FoxO signaling pathways. Alternative splicing analysis identified an average of 27,226 and 28,290 events in the heart and brain tissues, respectively, with differential events between control and hypoxia-stressed groups. This study offers a holistic view of transcriptomic adaptations in A. nigrocauda heart and brain tissues under oxygen stress and emphasizes the role of gene expression and alternative splicing in the response mechanisms.
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Affiliation(s)
- Jian Chen
- Fisheries Research Institute, Wuhan Academy of Agricultural Sciences, Wuhan, China
| | - Zhen Hu
- Hubei Provincial Fisheries Technology Extension Center, Wuhan, China
| | - Pei Li
- Fisheries Research Institute, Wuhan Academy of Agricultural Sciences, Wuhan, China
| | - Guiying Wang
- Fisheries Research Institute, Wuhan Academy of Agricultural Sciences, Wuhan, China
| | - Huijie Wei
- Fisheries Research Institute, Wuhan Academy of Agricultural Sciences, Wuhan, China
| | - Qing Li
- Fisheries Research Institute, Wuhan Academy of Agricultural Sciences, Wuhan, China
| | - Beide Fu
- Ruibiao (Wuhan) Biotechnology Co., Ltd, Wuhan, China
| | - Yanhong Sun
- Fisheries Research Institute, Wuhan Academy of Agricultural Sciences, Wuhan, China
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Fagbohun IR, Akindele EO, Adedapo AM, Aliu OO. Assessment of the biological water quality and response of freshwater macroinvertebrates to thermal stress in an Afrotropical warm spring. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:47755-47768. [PMID: 36740614 DOI: 10.1007/s11356-023-25670-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Accepted: 01/28/2023] [Indexed: 02/07/2023]
Abstract
Freshwater macroinvertebrates have been widely used as environmental stress indicators. However, information on their response to natural thermal stress is relatively scarce, particularly in the tropics. Using the multimetric macroinvertebrate approach, the biological water quality of the warm and cold springs of the Ikogosi Warm Spring in Nigeria was evaluated, with a view to ascertaining the response of freshwater macroinvertebrates to natural thermal stress. Macroinvertebrates and water samples were collected from the warm (stressed) and cold (less-stressed) springs, as well as the confluence stream, within the renowned Ikogosi Warm Spring of Southwest Nigeria. The less-stressed cold spring had much more dissolved oxygen than the warm spring and other thermally stressed stations but less than the warm spring and other thermally stressed stations for water temperature, electrical conductivity, total dissolved solids, Ca2+, Mg2+, and water hardness. Generally, the macroinvertebrate taxonomic richness (30 species) and EPT richness (3 species) of the Ikogosi Warm Spring indicated an impaired freshwater system. Using the multimetric macroinvertebrate index (MMI), the warm spring was of poor biological water quality while the cold spring was of good biological water quality. At the confluence of both springs, the MMI declined to poor and moderate water quality. Although the thermal stress of the Ikogosi Warm Spring is natural, the government should take the necessary steps to regulate tourist activities so that the site's naturalness is preserved and the water quality is not further degraded on account of human-induced stressors such as deforestation, waste dumping, and washing activities.
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Vazquez Roman KN, Burggren WW. Metabolic responses to crude oil during early life stages reveal critical developmental windows in the zebrafish (Danio rerio). Comp Biochem Physiol C Toxicol Pharmacol 2022; 254:109274. [PMID: 35051628 DOI: 10.1016/j.cbpc.2022.109274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 12/07/2021] [Accepted: 01/12/2022] [Indexed: 11/03/2022]
Abstract
Morphological effects of crude oil exposure on early development in fishes have been well documented, but crude oil's metabolic effects and when in early development these effects might be most prominent remains unclear. We hypothesized that zebrafish (Danio rerio) exposed to crude oil as a high energy water accommodated fraction (HEWAF) would show increased routine oxygen consumption (ṀO2) and critical oxygen tension (PCrit) and this effect would be dependent upon day of HEWAF exposure, revealing critical windows of development for exposure effects. Zebrafish were exposed to 0%, 10%, 25%, 50% or 100% HEWAF for 24 h during one of the first six days post-fertilization (dpf). Survival rate, body mass, routine ṀO2, and PCrit were then measured at 7 dpf. Survival rate and especially body mass were both decreased based on both exposure concentration and day of crude oil exposure, with the largest decrease when HEWAF exposure occurred at 3 dpf. HEWAF effects on routine ṀO2 also differed depending upon exposure day. The largest effect occurred at 3 dpf, when ṀO2 increased significantly by ~60% from 10.1 ± 0.8 μmol O2/g/h compared to control group value of 6.3 ± 0.4 μmol O2/g/h. No significant effects of HEWAF exposure on any day were evident for PCrit (85 ± 4 mmHg in the control population). Overall, the main effects on body mass and ṀO2 measured at 7 dpf occurred when HEWAF exposures occurred at ~3 dpf. This critical window for metabolism in zebrafish larvae coincides with time of hatching, which may represent an especially vulnerable period in development.
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Affiliation(s)
- Karem N Vazquez Roman
- Developmental Integrative Biology Research Group, Department of Biological Sciences, University of North Texas, Denton, TX, USA.
| | - Warren W Burggren
- Developmental Integrative Biology Research Group, Department of Biological Sciences, University of North Texas, Denton, TX, USA
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6
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Mugwanya M, Dawood MA, Kimera F, Sewilam H. Anthropogenic temperature fluctuations and their effect on aquaculture: A comprehensive review. AQUACULTURE AND FISHERIES 2022. [DOI: 10.1016/j.aaf.2021.12.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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7
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Aranda-Morales SA, Peña-Marín ES, Jiménez-Martínez LD, Martínez-Burguete T, Martínez-Bautista G, Álvarez-Villagómez CS, De la Rosa-García S, Camarillo-Coop S, Martínez-García R, Guzmán-Villanueva LT, Álvarez-González CA. Expression of ion transport proteins and routine metabolism in juveniles of tropical gar (Atractosteus tropicus) exposed to ammonia. Comp Biochem Physiol C Toxicol Pharmacol 2021; 250:109166. [PMID: 34411697 DOI: 10.1016/j.cbpc.2021.109166] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 07/13/2021] [Accepted: 08/06/2021] [Indexed: 12/14/2022]
Abstract
Tropical gar (Atractosteus tropicus) thrives in aquatic habitats with high levels of total nitrogen (TAN) and unionized ammonia (NH3). However, the tolerance of TAN and NH3, the excretion mechanisms involved, and the effects of these chemicals on routine metabolism are still unknown. Therefore, our objectives were to assess the acute toxicity of TAN and NH3 in A. tropicus juveniles after a 96-h exposure (LC50-96 h) to NH4Cl and after chronic exposure to two concentrations (15% and 30% of LC50-96 h TAN) for 12 days, as well as to evaluate the transcriptional effects associated with Rhesus proteins (rhag, rhbg, rhcg) and ion transporters (NHE, NKA, NKCC, and CFTR) in gills and skin; and to determine the effects of TAN and NH3 on routine metabolism through oxygen consumption (μM g-1 h-1) and gill ventilation frequency (beats min-1). LC50-96 h values were 100.20 ± 11.21 mg/L for TAN and 3.756 ± 0.259 mg/L for NH3. The genes encoding Rhesus proteins and ion transporters in gills and skin showed a differential expression according to TAN concentrations and exposure time. Oxygen consumption on day 12 showed significant differences between treatments with 15% and 30% TAN. Gill ventilation frequency on day 12 was higher in fish exposed to 30% TAN. In conclusion, A. tropicus juveniles are highly tolerant to TAN, showing upregulation of the genes involved in TAN excretion through gills and skin, which affects routine oxygen consumption and energetic cost. These findings are relevant for understanding adaptations in the physiological response of a tropical ancestral air-breathing fish.
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Affiliation(s)
- Sonia A Aranda-Morales
- División Académica de Ciencias Biológicas, Universidad Juárez Autónoma de Tabasco, Carretera Villahermosa-Cárdenas Km 0.5, C.P.86139 Villahermosa, Tabasco, Mexico
| | - Emyr S Peña-Marín
- División Académica de Ciencias Biológicas, Universidad Juárez Autónoma de Tabasco, Carretera Villahermosa-Cárdenas Km 0.5, C.P.86139 Villahermosa, Tabasco, Mexico; Consejo Nacional de Ciencia y Tecnología, Av. Insurgentes Sur 1582, Col. Crédito Constructor, Del. Benito Juárez C.P. 03940, Mexico
| | - Luis D Jiménez-Martínez
- División Académica Multidisciplinaria de Jalpa de Méndez, Universidad Juárez Autónoma de Tabasco, Carretera Nacajuca-Jalpa de Méndez R/a Rivera Alta, C.P. 86200 Jalpa de Méndez, Tabasco, Mexico
| | - Talhia Martínez-Burguete
- División Académica de Ciencias Biológicas, Universidad Juárez Autónoma de Tabasco, Carretera Villahermosa-Cárdenas Km 0.5, C.P.86139 Villahermosa, Tabasco, Mexico
| | - Gil Martínez-Bautista
- División Académica de Ciencias Biológicas, Universidad Juárez Autónoma de Tabasco, Carretera Villahermosa-Cárdenas Km 0.5, C.P.86139 Villahermosa, Tabasco, Mexico
| | - Carina S Álvarez-Villagómez
- División Académica de Ciencias Biológicas, Universidad Juárez Autónoma de Tabasco, Carretera Villahermosa-Cárdenas Km 0.5, C.P.86139 Villahermosa, Tabasco, Mexico
| | - Susana De la Rosa-García
- División Académica de Ciencias Biológicas, Universidad Juárez Autónoma de Tabasco, Carretera Villahermosa-Cárdenas Km 0.5, C.P.86139 Villahermosa, Tabasco, Mexico
| | - Susana Camarillo-Coop
- División Académica de Ciencias Biológicas, Universidad Juárez Autónoma de Tabasco, Carretera Villahermosa-Cárdenas Km 0.5, C.P.86139 Villahermosa, Tabasco, Mexico
| | - Rafael Martínez-García
- División Académica de Ciencias Biológicas, Universidad Juárez Autónoma de Tabasco, Carretera Villahermosa-Cárdenas Km 0.5, C.P.86139 Villahermosa, Tabasco, Mexico
| | - Laura T Guzmán-Villanueva
- Consejo Nacional de Ciencia y Tecnología, Av. Insurgentes Sur 1582, Col. Crédito Constructor, Del. Benito Juárez C.P. 03940, Mexico; Centro de Investigaciones Biológicas del Noroeste S.C., Av. Instituto Politécnico Nacional 195. Col. Playa Palo de Santa Rita Sur, 23096 La Paz, Baja California Sur, Mexico
| | - Carlos A Álvarez-González
- División Académica de Ciencias Biológicas, Universidad Juárez Autónoma de Tabasco, Carretera Villahermosa-Cárdenas Km 0.5, C.P.86139 Villahermosa, Tabasco, Mexico.
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Braz-Mota S, Almeida-Val VMF. Ecological adaptations of Amazonian fishes acquired during evolution under environmental variations in dissolved oxygen: A review of responses to hypoxia in fishes, featuring the hypoxia-tolerant Astronotus spp. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2021; 335:771-786. [PMID: 34338442 DOI: 10.1002/jez.2531] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 06/25/2021] [Accepted: 07/12/2021] [Indexed: 11/06/2022]
Abstract
The Amazon Basin presents a dynamic regime of dissolved oxygen (DO) oscillations, which varies among habitats within the basin, including spatially, daily, and seasonally. Fish species inhabiting these environments have developed many physiological adaptations to deal with the frequent and periodic events of low (hypoxia), or no (anoxia) DO in the water. Cichlid fishes, especially the genus Astronotus (A. ocellatus and A. crassipinnis), are hypoxic-tolerant species that can survive in very low DO levels for long periods, while adults often inhabit places where DO is close to zero. The present review will focus on some metabolic adjustments that Amazonian fish use in response to hypoxic conditions, which include many strategies from behavioral, morphological, physiological, and biochemical strategies. These strategies include ASR (aerial surface respiration), lip expansion, branchial tissue remodeling, increases in glycolytic metabolism with the increase of blood glucose levels, and increases in anaerobic metabolism with increases of plasma lactate levels. Other groups over evolutionary time developed obligate aerial respiration with changes in pharyngeal and swim bladder vascularization as well as the development of a true lung. However, most species are water-breathing species, such as A. ocellatus and A. crassipinnis, which are detailed in this study because they are used as hypoxia-tolerant model fish. Herein, we draw together the literature data of the physiological mechanisms by which these species decrease aerobic metabolism and increase anaerobic metabolism to survive hypoxia. This is the first attempt to synthesize the physiological mechanisms of the hypoxia-tolerant Astronotus species.
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Affiliation(s)
- Susana Braz-Mota
- Laboratory of Ecophysiology and Molecular Evolution, Brazilian National Institute for Research in the Amazon, Manaus, Amazonas, Brazil
| | - Vera M F Almeida-Val
- Laboratory of Ecophysiology and Molecular Evolution, Brazilian National Institute for Research in the Amazon, Manaus, Amazonas, Brazil
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Seibel BA, Andres A, Birk MA, Burns AL, Shaw CT, Timpe AW, Welsh CJ. Oxygen supply capacity breathes new life into critical oxygen partial pressure (Pcrit). J Exp Biol 2021; 224:jeb.242210. [PMID: 33692079 DOI: 10.1242/jeb.242210] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 03/01/2021] [Indexed: 12/11/2022]
Abstract
The critical oxygen partial pressure (Pcrit), typically defined as the PO2 below which an animal's metabolic rate (MR) is unsustainable, is widely interpreted as a measure of hypoxia tolerance. Here, Pcrit is defined as the PO2 at which physiological oxygen supply (α0) reaches its maximum capacity (α; µmol O2 g-1 h-1 kPa-1). α is a species- and temperature-specific constant describing the oxygen dependency of the maximum metabolic rate (MMR=PO2×α) or, equivalently, the MR dependence of Pcrit (Pcrit=MR/α). We describe the α-method, in which the MR is monitored as oxygen declines and, for each measurement period, is divided by the corresponding PO2 to provide the concurrent oxygen supply (α0=MR/PO2). The highest α0 value (or, more conservatively, the mean of the three highest values) is designated as α. The same value of α is reached at Pcrit for any MR regardless of previous or subsequent metabolic activity. The MR need not be constant (regulated), standardized or exhibit a clear breakpoint at Pcrit for accurate determination of α. The α-method has several advantages over Pcrit determination and non-linear analyses, including: (1) less ambiguity and greater accuracy, (2) fewer constraints in respirometry methodology and analysis, and (3) greater predictive power and ecological and physiological insight. Across the species evaluated here, α values are correlated with MR, but not Pcrit. Rather than an index of hypoxia tolerance, Pcrit is a reflection of α, which evolves to support maximum energy demands and aerobic scope at the prevailing temperature and oxygen level.
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Affiliation(s)
- Brad A Seibel
- College of Marine Science, University of South Florida, St Petersburg, FL 33701, USA
| | - Alyssa Andres
- College of Marine Science, University of South Florida, St Petersburg, FL 33701, USA
| | - Matthew A Birk
- College of Marine Science, University of South Florida, St Petersburg, FL 33701, USA
| | - Alexandra L Burns
- College of Marine Science, University of South Florida, St Petersburg, FL 33701, USA
| | - C Tracy Shaw
- College of Marine Science, University of South Florida, St Petersburg, FL 33701, USA
| | - Alexander W Timpe
- College of Marine Science, University of South Florida, St Petersburg, FL 33701, USA
| | - Christina J Welsh
- College of Marine Science, University of South Florida, St Petersburg, FL 33701, USA
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Driedzic WR, MacCormack TJ, Lamarre SG. Contrasting strategies of hypoxic cardiac performance and metabolism in cichlids and armoured catfish. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2021; 335:787-800. [PMID: 33830679 DOI: 10.1002/jez.2461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Revised: 03/19/2021] [Accepted: 03/22/2021] [Indexed: 11/07/2022]
Abstract
The heart of tropical fishes is a particularly useful model system in which to investigate mechanisms of hypoxic tolerance. Here we focus on insights gained from two groups of fishes, cichlids and armoured catfishes. Cichlids respond to hypoxia by entering a sustained hypometabolism with decreased heart performance to match whole animal circulatory needs. Heart rate is decreased along with protein turnover to reduce adenosine triphosphate demand. This occurs despite the inherent capacity for high levels of cardiac power development. Although highly hypoxic tolerant at the whole animal level, the heart of cichlids does not have high constitutive activities of glycolytic enzymes compared to other species. Information is conflicting with respect to changes in glycolytic gene expression and enzyme activity following hypoxic exposure with some studies showing increases and others decreases. In contrast to cichlids, species of armoured catfish, that are routinely exposed to water of low oxygen content, do not display hypoxic bradycardia. Under hypoxia there are early changes in glucose trafficking suggestive of activation of glycolysis before lactate accumulation. Thereafter, heart glycogen is mobilized and lactate accumulates in both heart and blood, in some species to very high levels. Heart performance under hypoxia is enhanced by defense of intracellular pH. A functional sarcoplasmic reticulum and binding of hexokinase to the outer mitochondrial membrane may also play a role in cardioprotection. Maintenance of heart performance under hypoxia may relate to a tradeoff between air breathing via a modified stomach and circulatory demands for digestion.
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Affiliation(s)
- William R Driedzic
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
| | - Tyson J MacCormack
- Department of Chemistry and Biochemistry, Mount Allison University, Sackville, New Brunswick, Canada
| | - Simon G Lamarre
- Département de Biologie, Université de Moncton, Moncton, New Brunswick, Canada
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Obirikorang KA, Ofori AGA, Gyampoh BA. Dominance hierarchies within different size groupings of Nile tilapia (Oreochromis niloticus) and effects on growth and physiological responses. AFRICAN ZOOLOGY 2020. [DOI: 10.1080/15627020.2020.1756909] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Kwasi Adu Obirikorang
- Department of Fisheries and Watershed Management, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Anthea Georgina Ama Ofori
- Department of Fisheries and Watershed Management, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Benjamin Apraku Gyampoh
- Department of Fisheries and Watershed Management, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
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12
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Seibel BA, Deutsch C. Oxygen supply capacity in animals evolves to meet maximum demand at the current oxygen partial pressure regardless of size or temperature. J Exp Biol 2020; 223:jeb210492. [PMID: 32376709 DOI: 10.1242/jeb.210492] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Accepted: 05/04/2020] [Indexed: 01/03/2023]
Abstract
The capacity to extract oxygen from the environment and transport it to respiring tissues in support of metabolic demand reportedly has implications for species' thermal tolerance, body size, diversity and biogeography. Here, we derived a quantifiable linkage between maximum and basal metabolic rate and their oxygen, temperature and size dependencies. We show that, regardless of size or temperature, the physiological capacity for oxygen supply precisely matches the maximum evolved demand at the highest persistently available oxygen pressure and this is the critical PO2 for the maximum metabolic rate, Pcrit-max For most terrestrial and shallow-living marine species, Pcrit-max is the current atmospheric pressure, 21 kPa. Any reduction in oxygen partial pressure from current values will result in a calculable decrement in maximum metabolic performance. However, oxygen supply capacity has evolved to match demand across temperatures and body sizes and so does not constrain thermal tolerance or cause the well-known reduction in mass-specific metabolic rate with increasing body mass. The critical oxygen pressure for resting metabolic rate, typically viewed as an indicator of hypoxia tolerance, is, instead, simply a rate-specific reflection of the oxygen supply capacity. A compensatory reduction in maintenance metabolic costs in warm-adapted species constrains factorial aerobic scope and the critical PO2 to a similar range, between ∼2 and 6, across each species' natural temperature range. The simple new relationship described here redefines many important physiological concepts and alters their ecological interpretation.
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Affiliation(s)
- Brad A Seibel
- College of Marine Science, University of South Florida, St Petersburg, FL 33701, USA
| | - Curtis Deutsch
- School of Oceanography, University of Washington, 1492 NE Boat Street, Seattle, WA 98105, USA
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Burggren WW, Arriaga-Bernal JC, Méndez-Arzate PM, Méndez-Sánchez JF. Metabolic physiology of the Mayan cichlid fish (Mayaheros uropthalmus): Re-examination of classification as an oxyconformer. Comp Biochem Physiol A Mol Integr Physiol 2019; 237:110538. [DOI: 10.1016/j.cbpa.2019.110538] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 08/05/2019] [Accepted: 08/07/2019] [Indexed: 11/16/2022]
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Garduño Paz MV, Méndez Sánchez JF, Burggren W, García Martínez JLA. Metabolic rate and hypoxia tolerance in Girardinichthys multiradiatus (Pisces: Goodeidae), an endemic fish at high altitude in tropical Mexico. Comp Biochem Physiol A Mol Integr Physiol 2019; 239:110576. [PMID: 31526846 DOI: 10.1016/j.cbpa.2019.110576] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 08/30/2019] [Accepted: 09/10/2019] [Indexed: 11/18/2022]
Abstract
The darkedged splitfin (Amarillo fish), Girardinichthys multiradiatus is a vulnerable endemic fish species inhabiting central Mexico's high altitude Upper Lerma Basin, where aquatic hypoxia is exacerbated by low barometric pressures (lower PO2s), large aquatic oxygen changes, poor aquatic systems management and urban, agricultural and industrial pollution. The respiratory physiology of G. multiradiatus under such challenging conditions is unknown - therefore the main goal of the present study was to determine metabolic rates and hypoxia tolerance to elucidate possible physiological adaptations allowing this fish to survive high altitude and increasingly eutrophic conditions. Fish came from two artificial reservoirs - San Elías and Ex Hacienda - considered refuges for this species. Both reservoirs showed high dial PO2 variation, with hypoxic conditions before midday and after 20:00 h, ~4 h of normoxia (15 kPa) from 16:00-20:00, and ~4 h of hyperoxia (16-33 kPa) from 12:00-16:00. Standard metabolic rate at 20 ± 0.5 °C of larvae from Ex Hacienda was significantly higher than those from San Elías, but these differences disappeared in juveniles and adults. Metabolic rate at 20 ± 0.5 °C for adults was 9.8 ± 0.1 SEM μmol O2/g/h. The metabolic scaling exponent for adults was 0.58 for San Elías fish and 0.83 for Ex Hacienda fish, indicating possible ecological effects on this variable. Post-larval fish in Ex Hacienda and all stages in San Elias site showed considerable hypoxia tolerance, with PCrit mean values ranging from 1.9-3.1 kPa, lower than those of many tropical fish at comparable temperatures. Collectively, these data indicate that G. multiradiatus is well adapted for the hypoxia associated with their high-altitude habitat.
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Affiliation(s)
- Monica Vanessa Garduño Paz
- Laboratorio de Ecofisiología Animal, Facultad de Ciencias, Universidad Autónoma del Estado de México, El Cerrillo Piedras Blancas carretera Toluca-Ixtlahuaca km 14.5, CP 50200 Toluca, Estado de México, Mexico.
| | - José Fernando Méndez Sánchez
- Laboratorio de Ecofisiología Animal, Facultad de Ciencias, Universidad Autónoma del Estado de México, El Cerrillo Piedras Blancas carretera Toluca-Ixtlahuaca km 14.5, CP 50200 Toluca, Estado de México, Mexico
| | - Warren Burggren
- Developmental Physiology Lab, Department of Biological Sciences, University of North Texas, 1155 Union Circle #311277, Denton, TX 76203-5017, United States of America
| | - José Luis Antonio García Martínez
- Laboratorio de Ecofisiología Animal, Facultad de Ciencias, Universidad Autónoma del Estado de México, El Cerrillo Piedras Blancas carretera Toluca-Ixtlahuaca km 14.5, CP 50200 Toluca, Estado de México, Mexico
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