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Appelman B, Charlton BT, Goulding RP, Kerkhoff TJ, Breedveld EA, Noort W, Offringa C, Bloemers FW, van Weeghel M, Schomakers BV, Coelho P, Posthuma JJ, Aronica E, Joost Wiersinga W, van Vugt M, Wüst RCI. Muscle abnormalities worsen after post-exertional malaise in long COVID. Nat Commun 2024; 15:17. [PMID: 38177128 PMCID: PMC10766651 DOI: 10.1038/s41467-023-44432-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 12/13/2023] [Indexed: 01/06/2024] Open
Abstract
A subgroup of patients infected with SARS-CoV-2 remain symptomatic over three months after infection. A distinctive symptom of patients with long COVID is post-exertional malaise, which is associated with a worsening of fatigue- and pain-related symptoms after acute mental or physical exercise, but its underlying pathophysiology is unclear. With this longitudinal case-control study (NCT05225688), we provide new insights into the pathophysiology of post-exertional malaise in patients with long COVID. We show that skeletal muscle structure is associated with a lower exercise capacity in patients, and local and systemic metabolic disturbances, severe exercise-induced myopathy and tissue infiltration of amyloid-containing deposits in skeletal muscles of patients with long COVID worsen after induction of post-exertional malaise. This study highlights novel pathways that help to understand the pathophysiology of post-exertional malaise in patients suffering from long COVID and other post-infectious diseases.
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Affiliation(s)
- Brent Appelman
- Amsterdam UMC location University of Amsterdam, Center for Experimental and Molecular Medicine, Meibergdreef 9, Amsterdam, the Netherlands
- Amsterdam Institute for Infection and Immunity, Infectious diseases, Amsterdam, the Netherlands
| | - Braeden T Charlton
- Department of Human Movement Sciences, Faculty of Behavioral and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
- Amsterdam Movement Sciences, Amsterdam, the Netherlands
| | - Richie P Goulding
- Department of Human Movement Sciences, Faculty of Behavioral and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
- Amsterdam Movement Sciences, Amsterdam, the Netherlands
| | - Tom J Kerkhoff
- Department of Human Movement Sciences, Faculty of Behavioral and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
- Amsterdam Movement Sciences, Amsterdam, the Netherlands
- Department of Physiology, Amsterdam UMC location Vrije Universiteit Amsterdam, De Boelelaan 1117, Amsterdam, the Netherlands
- Amsterdam Cardiovascular Sciences, Amsterdam, the Netherlands
| | - Ellen A Breedveld
- Department of Human Movement Sciences, Faculty of Behavioral and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
- Amsterdam Movement Sciences, Amsterdam, the Netherlands
| | - Wendy Noort
- Department of Human Movement Sciences, Faculty of Behavioral and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
- Amsterdam Movement Sciences, Amsterdam, the Netherlands
| | - Carla Offringa
- Department of Human Movement Sciences, Faculty of Behavioral and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
- Amsterdam Movement Sciences, Amsterdam, the Netherlands
| | - Frank W Bloemers
- Amsterdam Movement Sciences, Amsterdam, the Netherlands
- Department of Trauma Surgery, Amsterdam UMC location University of Amsterdam, Meibergdreef 9, Amsterdam, the Netherlands
| | - Michel van Weeghel
- Laboratory Genetic Metabolic Diseases, Core Facility Metabolomics, Amsterdam UMC location University of Amsterdam, Meibergdreef 9, Amsterdam, the Netherlands
| | - Bauke V Schomakers
- Laboratory Genetic Metabolic Diseases, Core Facility Metabolomics, Amsterdam UMC location University of Amsterdam, Meibergdreef 9, Amsterdam, the Netherlands
| | - Pedro Coelho
- Serviço de Neurologia, Departamento de Neurociências e Saúde Mental, Hospital de Santa Maria, CHULN, Lisbon, Portugal
- Faculdade de Medicina, Centro de Estudos Egas Moniz, University of Lisbon, Lisbon, Portugal
- Department of (Neuro)pathology, Amsterdam Neuroscience, Amsterdam UMC location University of Amsterdam, Meibergdreef 9, Amsterdam, the Netherlands
| | - Jelle J Posthuma
- Department of Trauma Surgery, Amsterdam UMC location University of Amsterdam, Meibergdreef 9, Amsterdam, the Netherlands
- Flevoziekenhuis, Division of Surgery, Hospitaalweg 1, Almere, the Netherlands
| | - Eleonora Aronica
- Department of (Neuro)pathology, Amsterdam Neuroscience, Amsterdam UMC location University of Amsterdam, Meibergdreef 9, Amsterdam, the Netherlands
| | - W Joost Wiersinga
- Amsterdam UMC location University of Amsterdam, Center for Experimental and Molecular Medicine, Meibergdreef 9, Amsterdam, the Netherlands
- Amsterdam Institute for Infection and Immunity, Infectious diseases, Amsterdam, the Netherlands
- Division of Infectious Diseases, Department of Internal Medicine, Amsterdam UMC location University of Amsterdam, Meibergdreef 9, Amsterdam, the Netherlands
| | - Michèle van Vugt
- Amsterdam Institute for Infection and Immunity, Infectious diseases, Amsterdam, the Netherlands.
- Division of Infectious Diseases, Tropical Medicine, Department of Medicine, Amsterdam UMC location University of Amsterdam, Meibergdreef 9, Amsterdam, the Netherlands.
| | - Rob C I Wüst
- Department of Human Movement Sciences, Faculty of Behavioral and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands.
- Amsterdam Movement Sciences, Amsterdam, the Netherlands.
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Lee YT, Tan YJ, Oon CE. BZD9L1 Differentially Regulates Sirtuins in Liver-Derived Cells by Inducing Reactive Oxygen Species. Biomedicines 2023; 11:3059. [PMID: 38002059 PMCID: PMC10669747 DOI: 10.3390/biomedicines11113059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 11/04/2023] [Accepted: 11/06/2023] [Indexed: 11/26/2023] Open
Abstract
Growing evidence has highlighted that mitochondrial dysfunction contributes to drug-induced toxicities and leads to drug attrition and post-market withdrawals. The acetylation or deacetylation of mitochondrial proteins can affect mitochondrial functions as the cells adapt to various cellular stresses and other metabolic challenges. SIRTs act as critical deacetylases in modulating mitochondrial function in response to drug toxicity, oxidative stress, reactive oxygen species (ROS), and energy metabolism. We previously showed that a recently characterised SIRT inhibitor (BZD9L1) is non-toxic in rodents in a short-term toxicity evaluation. However, the impact of BZD9L1 on mitochondrial function is unknown. This work aims to determine the effects of BZD9L1 on mitochondrial function in human normal liver and kidney-derived cell lines using the Agilent Seahorse Cell Mito Stress Test to complement our short-term toxicity evaluations in vivo. The Mito Stress assay revealed that BZD9L1 could potentially trigger oxidative stress by inducing ROS, which promotes proton leak and reduces coupling efficiency in liver-derived THLE cells. However, the same was not observed in human kidney-derived HEK293 cells. Interestingly, BZD9L1 had no impact on SIRT3 protein expression in both cell lines but affected SOD2 and its acetylated form at 72 h in THLE cells, indicating that BZD9L1 exerted its effect through SIRT3 activity rather than protein expression. In contrast, BZD9L1 reduced SIRT1 protein expression and impacted the p53 protein differently in both cell lines. Although BZD9L1 did not affect the spare respiratory capacity in vitro, these findings call for further validation of mitochondrial function through assessment of other mitochondrial parameters to evaluate the safety of BZD9L1.
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Affiliation(s)
| | | | - Chern Ein Oon
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, Gelugor 11800, Penang, Malaysia; (Y.T.L.); (Y.J.T.)
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Onieva A, Martin J, R Cuesta-Aguirre D, Planells V, Coronado-Zamora M, Beyer K, Vega T, Lozano JE, Santos C, Aluja MP. Complete mitochondrial DNA profile in stroke: A geographical matched case-control study in Spanish population. Mitochondrion 2023; 73:51-61. [PMID: 37793469 DOI: 10.1016/j.mito.2023.10.001] [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: 01/17/2023] [Revised: 08/28/2023] [Accepted: 10/01/2023] [Indexed: 10/06/2023]
Abstract
INTRODUCTION Stroke, the second leading cause of death worldwide, is a complex disease influenced by many risk factors among which we can find reactive oxygen species (ROS). Since mitochondria are the main producers of cellular ROS, nowadays studies are trying to elucidate the role of these organelles and its DNA (mtDNA) variation in stroke risk. The aim of the present study was to perform a comprehensive evaluation of the association between mtDNA mutations and mtDNA content and stroke risk. MATERIAL AND METHODS Homoplasmic and heteroplasmic mutations of the mtDNA were analysed in a case-controls study using 110 S cases and their corresponding control individuals. Mitochondrial DNA copy number (mtDNA-CN) was analysed in 73 of those case-control pairs. RESULTS Our results suggest that haplogroup V, specifically variants m.72C > T, m.4580G > A, m.15904C > T and m.16298 T > C have a protective role in relation to stroke risk. On the contrary, variants m.73A > G, m.11719G > A and m.14766C > T appear to be genetic risk factors for stroke. In this study, we found no statistically significant association between stroke risk and mitochondrial DNA copy number. CONCLUSIONS These results demonstrate the possible role of mtDNA genetics on the pathogenesis of stroke, probably through alterations in mitochondrial ROS production.
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Affiliation(s)
- Ana Onieva
- Unitat d'Antropologia Biològica, Departament BAVE, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Barcelona, Spain.
| | - Joan Martin
- Department of Genetics and Microbiology, Faculty of Biosciences, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Barcelona, Spain
| | - Daniel R Cuesta-Aguirre
- Unitat d'Antropologia Biològica, Departament BAVE, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Barcelona, Spain
| | - Violeta Planells
- Unitat d'Antropologia Biològica, Departament BAVE, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Barcelona, Spain
| | - Marta Coronado-Zamora
- Institut de Biotecnologia i Biomedicina; Department of Genetics and Microbiology, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Barcelona, Spain
| | - Katrin Beyer
- Department of Pathology, Germans Trias i Pujol Research Institute, Badalona 08916 Barcelona, Spain
| | - Tomás Vega
- Dirección General de Salud Pública. Consejería de Sanidad. Junta de Castilla y León, 47007 Valladolid, Spain
| | - José Eugenio Lozano
- Dirección General de Salud Pública. Consejería de Sanidad. Junta de Castilla y León, 47007 Valladolid, Spain
| | - Cristina Santos
- Unitat d'Antropologia Biològica, Departament BAVE, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Barcelona, Spain
| | - Maria Pilar Aluja
- Unitat d'Antropologia Biològica, Departament BAVE, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Barcelona, Spain.
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Zhang R, Yang A, Zhang L, He L, Gu X, Yu C, Lu Z, Wang C, Zhou F, Li F, Ji L, Xing J, Guo H. MFN2 deficiency promotes cardiac response to hypobaric hypoxia by reprogramming cardiomyocyte metabolism. Acta Physiol (Oxf) 2023; 239:e14018. [PMID: 37401731 DOI: 10.1111/apha.14018] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 06/02/2023] [Accepted: 06/26/2023] [Indexed: 07/05/2023]
Abstract
AIM Under hypobaric hypoxia (HH), the heart triggers various defense mechanisms including metabolic remodeling against lack of oxygen. Mitofusin 2 (MFN2), located at the mitochondrial outer membrane, is closely involved in the regulation of mitochondrial fusion and cell metabolism. To date, however, the role of MFN2 in cardiac response to HH has not been explored. METHODS Loss- and gain-of-function approaches were used to investigate the role of MFN2 in cardiac response to HH. In vitro, the function of MFN2 in the contraction of primary neonatal rat cardiomyocytes under hypoxia was examined. Non-targeted metabolomics and mitochondrial respiration analyses, as well as functional experiments were performed to explore underlying molecular mechanisms. RESULTS Our data demonstrated that, following 4 weeks of HH, cardiac-specific MFN2 knockout (MFN2 cKO) mice exhibited significantly better cardiac function than control mice. Moreover, restoring the expression of MFN2 clearly inhibited the cardiac response to HH in MFN2 cKO mice. Importantly, MFN2 knockout significantly improved cardiac metabolic reprogramming during HH, resulting in reduced capacity for fatty acid oxidation (FAO) and oxidative phosphorylation, and increased glycolysis and ATP production. In vitro data showed that down-regulation of MFN2 promoted cardiomyocyte contractility under hypoxia. Interestingly, increased FAO through palmitate treatment decreased contractility of cardiomyocyte with MFN2 knockdown under hypoxia. Furthermore, treatment with mdivi-1, an inhibitor of mitochondrial fission, disrupted HH-induced metabolic reprogramming and subsequently promoted cardiac dysfunction in MFN2-knockout hearts. CONCLUSION Our findings provide the first evidence that down-regulation of MFN2 preserves cardiac function in chronic HH by promoting cardiac metabolic reprogramming.
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Affiliation(s)
- Ru Zhang
- State Key Laboratory of Cancer Biology and Department of Physiology and Pathophysiology, Air Force Medical University, Xi'an, China
- Department of Aerospace Physiology, Air Force Medical University, Xi'an, China
| | - Ailin Yang
- State Key Laboratory of Cancer Biology and Department of Physiology and Pathophysiology, Air Force Medical University, Xi'an, China
| | - Lin Zhang
- Department of Aerospace Physiology, Air Force Medical University, Xi'an, China
| | - Linjie He
- State Key Laboratory of Cancer Biology and Department of Physiology and Pathophysiology, Air Force Medical University, Xi'an, China
| | - Xiaoming Gu
- State Key Laboratory of Cancer Biology and Department of Physiology and Pathophysiology, Air Force Medical University, Xi'an, China
| | - Caiyong Yu
- Military Medical Innovation Center, Air Force Medical University, Xi'an, China
| | - Zhenxing Lu
- Institute of Medical Research, Northwestern Polytechnical University, Xi'an, China
| | - Chuang Wang
- College of Basic Medicine, Air Force Medical University, Xi'an, China
| | - Feng Zhou
- Department of General Surgery, The 71st Group Army Hospital of the People's Liberation Army, Xuzhou, China
| | - Fei Li
- Department of Cardiology, Xijing Hospital, Air Force Medical University, Xi'an, China
| | - Lele Ji
- State Key Laboratory of Cancer Biology and Department of Physiology and Pathophysiology, Air Force Medical University, Xi'an, China
- Experimental Teaching Center of Basic Medicine, Air Force Medical University, Xi'an, China
| | - Jinliang Xing
- State Key Laboratory of Cancer Biology and Department of Physiology and Pathophysiology, Air Force Medical University, Xi'an, China
| | - Haitao Guo
- State Key Laboratory of Cancer Biology and Department of Physiology and Pathophysiology, Air Force Medical University, Xi'an, China
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Mitochondrial Respiration in Response to Iron Deficiency Anemia: Comparison of Peripheral Blood Mononuclear Cells and Liver. Metabolites 2022; 12:metabo12030270. [PMID: 35323713 PMCID: PMC8950937 DOI: 10.3390/metabo12030270] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 03/14/2022] [Accepted: 03/18/2022] [Indexed: 02/04/2023] Open
Abstract
Iron is an essential component for metabolic processes, including oxygen transport within hemoglobin, tricarboxylic acid (TCA) cycle activity, and mitochondrial energy transformation. Iron deficiency can thus lead to metabolic dysfunction and eventually result in iron deficiency anemia (IDA), which affects approximately 1.5 billion people worldwide. Using a rat model of IDA induced by phlebotomy, we studied the effects of IDA on mitochondrial respiration in peripheral blood mononuclear cells (PBMCs) and the liver. Furthermore, we evaluated whether the mitochondrial function evaluated by high-resolution respirometry in PBMCs reflects corresponding alterations in the liver. Surprisingly, mitochondrial respiratory capacity was increased in PBMCs from rats with IDA compared to the controls. In contrast, mitochondrial respiration remained unaffected in livers from IDA rats. Of note, citrate synthase activity indicated an increased mitochondrial density in PBMCs, whereas it remained unchanged in the liver, partly explaining the different responses of mitochondrial respiration in PBMCs and the liver. Taken together, these results indicate that mitochondrial function determined in PBMCs cannot serve as a valid surrogate for respiration in the liver. Metabolic adaptions to iron deficiency resulted in different metabolic reprogramming in the blood cells and liver tissue.
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Fischer C, Volani C, Komlódi T, Seifert M, Demetz E, Valente de Souza L, Auer K, Petzer V, von Raffay L, Moser P, Gnaiger E, Weiss G. Dietary Iron Overload and Hfe-/- Related Hemochromatosis Alter Hepatic Mitochondrial Function. Antioxidants (Basel) 2021; 10:antiox10111818. [PMID: 34829689 PMCID: PMC8615072 DOI: 10.3390/antiox10111818] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 11/04/2021] [Accepted: 11/13/2021] [Indexed: 12/13/2022] Open
Abstract
Iron is an essential co-factor for many cellular metabolic processes, and mitochondria are main sites of utilization. Iron accumulation promotes production of reactive oxygen species (ROS) via the catalytic activity of iron species. Herein, we investigated the consequences of dietary and genetic iron overload on mitochondrial function. C57BL/6N wildtype and Hfe-/- mice, the latter a genetic hemochromatosis model, received either normal diet (ND) or high iron diet (HI) for two weeks. Liver mitochondrial respiration was measured using high-resolution respirometry along with analysis of expression of specific proteins and ROS production. HI promoted tissue iron accumulation and slightly affected mitochondrial function in wildtype mice. Hepatic mitochondrial function was impaired in Hfe-/- mice on ND and HI. Compared to wildtype mice, Hfe-/- mice on ND showed increased mitochondrial respiratory capacity. Hfe-/- mice on HI showed very high liver iron levels, decreased mitochondrial respiratory capacity and increased ROS production associated with reduced mitochondrial aconitase activity. Although Hfe-/- resulted in increased mitochondrial iron loading, the concentration of metabolically reactive cytoplasmic iron and mitochondrial density remained unchanged. Our data show multiple effects of dietary and genetic iron loading on mitochondrial function and linked metabolic pathways, providing an explanation for fatigue in iron-overloaded hemochromatosis patients, and suggests iron reduction therapy for improvement of mitochondrial function.
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Affiliation(s)
- Christine Fischer
- Department of Internal Medicine II, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria; (C.F.); (C.V.); (M.S.); (E.D.); (L.V.d.S.); (K.A.); (V.P.); (L.v.R.)
| | - Chiara Volani
- Department of Internal Medicine II, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria; (C.F.); (C.V.); (M.S.); (E.D.); (L.V.d.S.); (K.A.); (V.P.); (L.v.R.)
| | - Timea Komlódi
- Oroboros Instruments, Schöpfstrasse 18, 6020 Innsbruck, Austria; (T.K.); (E.G.)
| | - Markus Seifert
- Department of Internal Medicine II, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria; (C.F.); (C.V.); (M.S.); (E.D.); (L.V.d.S.); (K.A.); (V.P.); (L.v.R.)
- Christian Doppler Laboratory for Iron Metabolism and Anemia Research, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Egon Demetz
- Department of Internal Medicine II, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria; (C.F.); (C.V.); (M.S.); (E.D.); (L.V.d.S.); (K.A.); (V.P.); (L.v.R.)
| | - Lara Valente de Souza
- Department of Internal Medicine II, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria; (C.F.); (C.V.); (M.S.); (E.D.); (L.V.d.S.); (K.A.); (V.P.); (L.v.R.)
- Christian Doppler Laboratory for Iron Metabolism and Anemia Research, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Kristina Auer
- Department of Internal Medicine II, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria; (C.F.); (C.V.); (M.S.); (E.D.); (L.V.d.S.); (K.A.); (V.P.); (L.v.R.)
| | - Verena Petzer
- Department of Internal Medicine II, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria; (C.F.); (C.V.); (M.S.); (E.D.); (L.V.d.S.); (K.A.); (V.P.); (L.v.R.)
| | - Laura von Raffay
- Department of Internal Medicine II, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria; (C.F.); (C.V.); (M.S.); (E.D.); (L.V.d.S.); (K.A.); (V.P.); (L.v.R.)
| | - Patrizia Moser
- Department of Pathology, Innsbruck University Hospital, Anichstrasse 35, 6020 Innsbruck, Austria;
| | - Erich Gnaiger
- Oroboros Instruments, Schöpfstrasse 18, 6020 Innsbruck, Austria; (T.K.); (E.G.)
| | - Guenter Weiss
- Department of Internal Medicine II, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria; (C.F.); (C.V.); (M.S.); (E.D.); (L.V.d.S.); (K.A.); (V.P.); (L.v.R.)
- Christian Doppler Laboratory for Iron Metabolism and Anemia Research, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
- Correspondence: ; Tel.: +43-(0)512/504-23251
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Friedrich VK, Rubel MA, Schurr TG. Mitochondrial genetic variation in human bioenergetics, adaptation, and adult disease. Am J Hum Biol 2021; 34:e23629. [PMID: 34146380 DOI: 10.1002/ajhb.23629] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 05/27/2021] [Accepted: 05/28/2021] [Indexed: 12/16/2022] Open
Abstract
OBJECTIVES Mitochondria are critical for the survival of eukaryotic organisms due to their ability to produce cellular energy, which drives virtually all aspects of host biology. However, the effects of mitochondrial DNA (mtDNA) variation in relation to disease etiology and adaptation within contemporary global human populations remains incompletely understood. METHODS To develop a more holistic understanding of the role of mtDNA diversity in human adaptation, health, and disease, we investigated mitochondrial biology and bioenergetics. More specifically, we synthesized details from studies of mitochondrial function and variation in the context of haplogroup background, climatic adaptation, and oxidative disease. RESULTS The majority of studies show that mtDNA variation arose during modern human dispersal around the world. Some of these variants appear to have been positively selected for their adaptiveness in colder climates, with these sequence changes having implications for tissue-specific function and thermogenic capacity. In addition, many variants modulating energy production are also associated with damaging metabolic byproducts and mitochondrial dysfunction, which, in turn, are implicated in the onset and severity of several different adult mitochondrial diseases. Thus, mtDNA variation that governs bioenergetics, metabolism, and thermoregulation may potentially have adverse consequences for human health, depending on the genetic background and context in which it occurs. CONCLUSIONS Our review suggests that the mitochondrial research field would benefit from independently replicating mtDNA haplogroup-phenotype associations across global populations, incorporating potentially confounding environmental, demographic, and disease covariates into studies of mtDNA variation, and extending association-based studies to include analyses of complete mitogenomes and assays of mitochondrial function.
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Affiliation(s)
- Volney K Friedrich
- Department of Anthropology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Meagan A Rubel
- Department of Anthropology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Center for Translational Imaging and Precision Medicine, University of California - San Diego, La Jolla, California, USA
| | - Theodore G Schurr
- Department of Anthropology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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Jacobs RA, Lundby C. Contextualizing the biological relevance of standardized high-resolution respirometry to assess mitochondrial function in permeabilized human skeletal muscle. Acta Physiol (Oxf) 2021; 231:e13625. [PMID: 33570804 PMCID: PMC8047922 DOI: 10.1111/apha.13625] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 02/08/2021] [Accepted: 02/09/2021] [Indexed: 12/16/2022]
Abstract
Aim This study sought to provide a statistically robust reference for measures of mitochondrial function from standardized high‐resolution respirometry with permeabilized human skeletal muscle (ex vivo), compare analogous values obtained via indirect calorimetry, arterial‐venous O2 differences and 31P magnetic resonance spectroscopy (in vivo) and attempt to resolve differences across complementary methodologies as necessary. Methods Data derived from 831 study participants across research published throughout March 2009 to November 2019 were amassed to examine the biological relevance of ex vivo assessments under standard conditions, ie physiological temperatures of 37°C and respiratory chamber oxygen concentrations of ~250 to 500 μmol/L. Results Standard ex vivo‐derived measures are lower (Z ≥ 3.01, P ≤ .0258) en masse than corresponding in vivo‐derived values. Correcting respiratory values to account for mitochondrial temperatures 10°C higher than skeletal muscle temperatures at maximal exercise (~50°C): (i) transforms data to resemble (Z ≤ 0.8, P > .9999) analogous yet context‐specific in vivo measures, eg data collected during maximal 1‐leg knee extension exercise; and (ii) supports the position that maximal skeletal muscle respiratory rates exceed (Z ≥ 13.2, P < .0001) those achieved during maximal whole‐body exercise, e.g. maximal cycling efforts. Conclusion This study outlines and demonstrates necessary considerations when actualizing the biological relevance of human skeletal muscle respiratory control, metabolic flexibility and bioenergetics from standard ex vivo‐derived assessments using permeabilized human muscle. These findings detail how cross‐procedural comparisons of human skeletal muscle mitochondrial function may be collectively scrutinized in their relationship to human health and lifespan.
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Affiliation(s)
- Robert A. Jacobs
- Department of Human Physiology & Nutrition University of Colorado Colorado Springs (UCCS) Colorado Springs CO USA
| | - Carsten Lundby
- Innland University of Applied Sciences Lillehammer Norway
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9
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Longman DP, Murray A, Roberts R, Oakley S, Wells JCK, Stock JT. Energetics as a driver of human morphological thermal adaptation; evidence from female ultra-endurance athletes. EVOLUTIONARY HUMAN SCIENCES 2021; 3:e22. [PMID: 37588555 PMCID: PMC10427328 DOI: 10.1017/ehs.2021.17] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Functional benefits of the morphologies described by Bergmann's and Allen's rules in human males have recently been reported. However, the functional implications of ecogeographical patterning in females remain poorly understood. Here, we report the findings of preliminary work analysing the association between body shape and performance in female ultramarathon runners (n = 36) competing in hot and cold environments. The body shapes differed between finishers of hot and cold races, and also between hot race finishers and non-finishers. Variability in race performance across different settings supports the notion that human phenotype is adapted to different thermal environments as ecogeographical patterns have reported previously. This report provides support for the recent hypothesis that the heightened thermal strain associated with prolonged physical activity in hot/cold environments may have driven the emergence of thermally adaptive phenotypes in our evolutionary past. These results also tentatively suggest that the relationship between morphology and performance may be stronger in female vs. male athletes. This potential sex difference is discussed with reference to the evolved unique energetic context of human female reproduction. Further work, with a larger sample size, is required to investigate the observed potential sex differences in the strength of the relationship between phenotype and performance.
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Affiliation(s)
- Daniel P. Longman
- School of Sport, Health and Exercise Sciences, Loughborough University, LoughboroughLE11 3TU, UK
| | - Alison Murray
- Department of Anthropology, University of Victoria, British Columbia, Canada
| | - Rebecca Roberts
- Department of Archaeology, University of Cambridge, CambridgeCB2 3QG, UK
| | - Saskia Oakley
- Department of Archaeology, University of Cambridge, CambridgeCB2 3QG, UK
| | - Jonathan C. K. Wells
- Childhood Nutrition Research Centre, Population, Policy and Practice Research and Teaching Programme, UCL Great Ormond Street Institute of Child Health, LondonWC1N 1EH, UK
| | - Jay T. Stock
- Department of Archaeology, University of Cambridge, CambridgeCB2 3QG, UK
- Department of Anthropology, Western University, Ontario, Canada
- Department of Archaeology, Max Planck Institute for the Science of Human History, Kahlaische Strasse 10, D-07745Jena, Germany
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Ivanova YM, Blondin DP. Examining the benefits of cold exposure as a therapeutic strategy for obesity and type 2 diabetes. J Appl Physiol (1985) 2021; 130:1448-1459. [PMID: 33764169 DOI: 10.1152/japplphysiol.00934.2020] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The pathogenesis of metabolic diseases such as obesity and type 2 diabetes are characterized by a progressive dysregulation in energy partitioning, often leading to end-organ complications. One emerging approach proposed to target this metabolic dysregulation is the application of mild cold exposure. In healthy individuals, cold exposure can increase energy expenditure and whole body glucose and fatty acid utilization. Repeated exposures can lower fasting glucose and insulin levels and improve dietary fatty acid handling, even in healthy individuals. Despite its apparent therapeutic potential, little is known regarding the effects of cold exposure in populations for which this stimulation could benefit the most. The few studies available have shown that both acute and repeated exposures to the cold can improve insulin sensitivity and reduce fasting glycemia in individuals with type 2 diabetes. However, critical gaps remain in understanding the prolonged effects of repeated cold exposures on glucose regulation and whole body insulin sensitivity in individuals with metabolic syndrome. Much of the metabolic benefits appear to be attributable to the recruitment of shivering skeletal muscles. However, further work is required to determine whether the broader recruitment of skeletal muscles observed during cold exposure can confer metabolic benefits that surpass what has been historically observed from endurance exercise. In addition, although cold exposure offers unique cardiovascular responses for a physiological stimulus that increases energy expenditure, further work is required to determine how acute and repeated cold exposure can impact cardiovascular responses and myocardial function across a broader scope of individuals.
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Affiliation(s)
- Yoanna M Ivanova
- Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Québec, Canada.,Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Denis P Blondin
- Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Québec, Canada.,Division of Neurology, Department of Medicine, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada
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11
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Jayakumari NR, Rajendran RS, Sivasailam A, Vimala SS, Nanda S, Manjunatha S, Pillai VV, Karunakaran J, Gopala S. Impaired substrate-mediated cardiac mitochondrial complex I respiration with unaltered regulation of fatty acid metabolism and oxidative stress status in type 2 diabetic Asian Indians. J Diabetes 2020; 12:542-555. [PMID: 32125087 DOI: 10.1111/1753-0407.13031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 01/22/2020] [Accepted: 02/10/2020] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND The cardiovascular complications associated with type 2 diabetes mellitus could be attributed to changes in myocardial mitochondrial metabolism. Though it is a known fact that permeabilized cardiac muscle fibers and isolated mitochondria are metabolically compromised in the Caucasian population, studies of Asian Indian myocardial mitochondrial function are lacking. Thus, the objective of the present study is to analyze if there is altered cardiac mitochondrial substrate utilization in diabetic Asian Indians. METHODS Mitochondrial substrate utilization was measured using high-resolution respirometry in isolated mitochondria prepared from right atrial appendage tissues of diabetic and nondiabetic subjects undergoing coronary artery bypass graft surgery. Western blotting and densitometric analysis were also done to compare the levels of proteins involved in fatty acid metabolism and regulation. RESULTS The mitochondrial oxygen consumption rate for fatty acid substrate was shown to be decreased in diabetic subjects compared to nondiabetic subjects along with an unvaried mitochondrial DNA copy number and uniform levels of electron transport chain complex proteins and proteins involved in fatty acid metabolism and regulation. Decreased glutamate but unchanged pyruvate-mediated state 3 respiration were also observed in diabetic subjects. CONCLUSION The current study reports deranged cardiac mitochondrial fatty acid-mediated complex I respiration in type 2 diabetic Asian Indians with comparable levels of regulators of fatty acid oxidation to that of nondiabetic myocardium. Altered glutamate-mediated mitochondrial respiration also points toward possible alterations in mitochondrial complex I activity. When compared with previous reports on other ethnic populations, the current study suggests that Asian Indian population too have altered cardiac mitochondrial substrate utilization.
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Affiliation(s)
- Nandini R Jayakumari
- Department of Biochemistry, Sree Chitra Tirunal Institute for Medical Sciences & Technology, Thiruvananthapuram, India
| | - Raji S Rajendran
- Department of Biochemistry, Sree Chitra Tirunal Institute for Medical Sciences & Technology, Thiruvananthapuram, India
| | - Ashok Sivasailam
- Department of Biochemistry, Sree Chitra Tirunal Institute for Medical Sciences & Technology, Thiruvananthapuram, India
| | - Surabhi S Vimala
- Department of Biochemistry, Sree Chitra Tirunal Institute for Medical Sciences & Technology, Thiruvananthapuram, India
| | - Saurabh Nanda
- Department of Cardiovascular and Thoracic Surgery, Sree Chitra Tirunal Institute for Medical Sciences & Technology, Thiruvananthapuram, India
| | - Shankarappa Manjunatha
- Division of Endocrinology, Diabetes, Metabolism, Nutrition, Mayo Clinic, Rochester, Minnesota, USA
- Department of Physiology, All India Institute of Medical Sciences, Bibi Nagar, Telangana, India
| | - Vivek V Pillai
- Department of Cardiovascular and Thoracic Surgery, Sree Chitra Tirunal Institute for Medical Sciences & Technology, Thiruvananthapuram, India
| | - Jayakumar Karunakaran
- Department of Cardiovascular and Thoracic Surgery, Sree Chitra Tirunal Institute for Medical Sciences & Technology, Thiruvananthapuram, India
| | - Srinivas Gopala
- Department of Biochemistry, Sree Chitra Tirunal Institute for Medical Sciences & Technology, Thiruvananthapuram, India
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12
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Carraro U. Thirty years of translational research in Mobility Medicine: Collection of abstracts of the 2020 Padua Muscle Days. Eur J Transl Myol 2020; 30:8826. [PMID: 32499887 PMCID: PMC7254447 DOI: 10.4081/ejtm.2019.8826] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 01/22/2020] [Indexed: 12/11/2022] Open
Abstract
More than half a century of skeletal muscle research is continuing at Padua University (Italy) under the auspices of the Interdepartmental Research Centre of Myology (CIR-Myo), the European Journal of Translational Myology (EJTM) and recently also with the support of the A&CM-C Foundation for Translational Myology, Padova, Italy. The Volume 30(1), 2020 of the EJTM opens with the collection of abstracts for the conference "2020 Padua Muscle Days: Mobility Medicine 30 years of Translational Research". This is an international conference that will be held between March 18-21, 2020 in Euganei Hills and Padova in Italy. The abstracts are excellent examples of translational research and of the multidimensional approaches that are needed to classify and manage (in both the acute and chronic phases) diseases of Mobility that span from neurologic, metabolic and traumatic syndromes to the biological process of aging. One of the typical aim of Physical Medicine and Rehabilitation is indeed to reduce pain and increase mobility enough to enable impaired persons to walk freely, garden, and drive again. The excellent contents of this Collection of Abstracts reflect the high scientific caliber of researchers and clinicians who are eager to present their results at the PaduaMuscleDays. A series of EJTM Communications will also add to this preliminary evidence.
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Affiliation(s)
- Ugo Carraro
- Interdepartmental Research Centre of Myology (CIR-Myo), Department of Biomedical Sciences, University of Padova, Italy
- A&C M-C Foundation for Translational Myology, Padova, Italy
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13
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Hunter GR, Moellering DR, Windham ST, Mathis SL, Bamman MM, Fisher G. Relationship between V̇o 2peak, cycle economy, and mitochondrial respiration in untrained/trained. J Appl Physiol (1985) 2019; 127:1562-1568. [PMID: 31556836 DOI: 10.1152/japplphysiol.00223.2019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Aerobic capacity is negatively related to locomotion economy. The purpose of this paper is to determine what effect aerobic exercise training has on the relationship between net cycling oxygen uptake (inverse of economy) and aerobic capacity [peak oxygen uptake (V̇o2peak)], as well as what role mitochondrial coupled and uncoupled respiration may play in whole body aerobic capacity and cycling economy. Cycling net oxygen uptake and V̇o2peak were evaluated on 31 premenopausal women before exercise training (baseline) and after 8-16 wk of aerobic training. Muscle tissue was collected from 15 subjects at baseline and post-training. Mitochondrial respiration assays were performed using high-resolution respirometry. Pre- (r = 0.46, P < 0.01) and postexercise training (r = 0.62, P < 0.01) V̇o2peak and cycling net oxygen uptake were related. In addition, uncoupled and coupled fat respiration were related both at baseline (r = 0.62, P < 0.01) and post-training (r = 0.89, P < 01). Post-training coupled (r = 0.74, P < 0.01) and uncoupled carbohydrate respiration (r = 0.52, P < 05) were related to cycle net oxygen uptake. In addition, correlations between V̇o2peak and cycle net oxygen uptake persist both at baseline and after training, even after adjusting for submaximal cycle respiratory quotient (an index of fat oxidation). These results suggest that the negative relationship between locomotion economy and aerobic capacity is increased following exercise training. In addition, it is proposed that at least one of the primary factors influencing this relationship has its foundation within the mitochondria. Strong relationships between coupled and uncoupled respiration appear to be contributing factors for this relationship.NEW & NOTEWORTHY The negative relationship between cycle economy and aerobic capacity is increased following exercise training. The strong relationship between coupled and uncoupled respiration, especially after training, appears to be contributing to this negative relationship between aerobic capacity and cycling economy, suggesting that mitochondrial economy is not increased following aerobic exercise training. These results are suggestive that training programs designed to improve locomotion economy should focus on changing biomechanics.
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Affiliation(s)
- Gary R Hunter
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, Alabama
| | - Douglas R Moellering
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, Alabama
| | - Samuel T Windham
- Department of Surgery, University of Alabama at Birmingham, Birmingham, Alabama
| | - Shannon L Mathis
- Department of Kinesiology, University of Alabama in Huntsville, Huntsville, Alabama
| | - Marcas M Bamman
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Gordon Fisher
- Department of Human Studies, University of Alabama at Birmingham, Birmingham, Alabama
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Exercise Mitigates the Loss of Muscle Mass by Attenuating the Activation of Autophagy during Severe Energy Deficit. Nutrients 2019; 11:nu11112824. [PMID: 31752260 PMCID: PMC6893734 DOI: 10.3390/nu11112824] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Revised: 10/30/2019] [Accepted: 11/14/2019] [Indexed: 01/07/2023] Open
Abstract
The loss of skeletal muscle mass with energy deficit is thought to be due to protein breakdown by the autophagy-lysosome and the ubiquitin-proteasome systems. We studied the main signaling pathways through which exercise can attenuate the loss of muscle mass during severe energy deficit (5500 kcal/day). Overweight men followed four days of caloric restriction (3.2 kcal/kg body weight day) and prolonged exercise (45 min of one-arm cranking and 8 h walking/day), and three days of control diet and restricted exercise, with an intra-subject design including biopsies from muscles submitted to distinct exercise volumes. Gene expression and signaling data indicate that the main catabolic pathway activated during severe energy deficit in skeletal muscle is the autophagy-lysosome pathway, without apparent activation of the ubiquitin-proteasome pathway. Markers of autophagy induction and flux were reduced by exercise primarily in the muscle submitted to an exceptional exercise volume. Changes in signaling are associated with those in circulating cortisol, testosterone, cortisol/testosterone ratio, insulin, BCAA, and leucine. We conclude that exercise mitigates the loss of muscle mass by attenuating autophagy activation, blunting the phosphorylation of AMPK/ULK1/Beclin1, and leading to p62/SQSTM1 accumulation. This includes the possibility of inhibiting autophagy as a mechanism to counteract muscle loss in humans under severe energy deficit.
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15
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Pharaoh G, Owen D, Yeganeh A, Premkumar P, Farley J, Bhaskaran S, Ashpole N, Kinter M, Van Remmen H, Logan S. Disparate Central and Peripheral Effects of Circulating IGF-1 Deficiency on Tissue Mitochondrial Function. Mol Neurobiol 2019; 57:1317-1331. [PMID: 31732912 PMCID: PMC7060968 DOI: 10.1007/s12035-019-01821-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 10/23/2019] [Indexed: 12/15/2022]
Abstract
Age-related decline in circulating levels of insulin-like growth factor (IGF)-1 is associated with reduced cognitive function, neuronal aging, and neurodegeneration. Decreased mitochondrial function along with increased reactive oxygen species (ROS) and accumulation of damaged macromolecules are hallmarks of cellular aging. Based on numerous studies indicating pleiotropic effects of IGF-1 during aging, we compared the central and peripheral effects of circulating IGF-1 deficiency on tissue mitochondrial function using an inducible liver IGF-1 knockout (LID). Circulating levels of IGF-1 (~ 75%) were depleted in adult male Igf1f/f mice via AAV-mediated knockdown of hepatic IGF-1 at 5 months of age. Cognitive function was evaluated at 18 months using the radial arm water maze and glucose and insulin tolerance assessed. Mitochondrial function was analyzed in hippocampus, muscle, and visceral fat tissues using high-resolution respirometry O2K as well as redox status and oxidative stress in the cortex. Peripherally, IGF-1 deficiency did not significantly impact muscle mass or mitochondrial function. Aged LID mice were insulin resistant and exhibited ~ 60% less adipose tissue but increased fat mitochondrial respiration (20%). The effects on fat metabolism were attributed to increases in growth hormone. Centrally, IGF-1 deficiency impaired hippocampal-dependent spatial acquisition as well as reversal learning in male mice. Hippocampal mitochondrial OXPHOS coupling efficiency and cortex ATP levels (~ 50%) were decreased and hippocampal oxidative stress (protein carbonylation and F2-isoprostanes) was increased. These data suggest that IGF-1 is critical for regulating mitochondrial function, redox status, and spatial learning in the central nervous system but has limited impact on peripheral (liver and muscle) metabolism with age. Therefore, IGF-1 deficiency with age may increase sensitivity to damage in the brain and propensity for cognitive deficits. Targeting mitochondrial function in the brain may be an avenue for therapy of age-related impairment of cognitive function. Regulation of mitochondrial function and redox status by IGF-1 is essential to maintain brain function and coordinate hippocampal-dependent spatial learning. While a decline in IGF-1 in the periphery may be beneficial to avert cancer progression, diminished central IGF-1 signaling may mediate, in part, age-related cognitive dysfunction and cognitive pathologies potentially by decreasing mitochondrial function.
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Affiliation(s)
- Gavin Pharaoh
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.,Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA.,Oklahoma Center for Geroscience, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Daniel Owen
- Oklahoma Center for Geroscience, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Alexander Yeganeh
- Oklahoma Center for Geroscience, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.,Oklahoma Center for Neuroscience, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Pavithra Premkumar
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Julie Farley
- Oklahoma Center for Geroscience, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Shylesh Bhaskaran
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA.,Oklahoma Center for Geroscience, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Nicole Ashpole
- Department of Biomolecular Sciences, University of Mississippi, Oxford, MS, USA
| | - Michael Kinter
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA.,Oklahoma Center for Geroscience, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Holly Van Remmen
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA.,Oklahoma Center for Geroscience, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.,Oklahoma Center for Neuroscience, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Sreemathi Logan
- Oklahoma Center for Geroscience, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA. .,Oklahoma Center for Neuroscience, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA. .,Department of Rehabilitation Sciences, College of Allied Health, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
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16
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Cardioprotective effects of idebenone do not involve ROS scavenging: Evidence for mitochondrial complex I bypass in ischemia/reperfusion injury. J Mol Cell Cardiol 2019; 135:160-171. [DOI: 10.1016/j.yjmcc.2019.08.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 08/20/2019] [Accepted: 08/21/2019] [Indexed: 12/20/2022]
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17
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Waters DL. Intermuscular Adipose Tissue: A Brief Review of Etiology, Association With Physical Function and Weight Loss in Older Adults. Ann Geriatr Med Res 2019; 23:3-8. [PMID: 32743278 PMCID: PMC7387605 DOI: 10.4235/agmr.19.0001] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 01/26/2019] [Accepted: 01/26/2019] [Indexed: 12/21/2022] Open
Abstract
Adipose tissue redistributes during aging resulting in increased intermuscular adipose tissue (IMAT), intramuscular, and intramyocellular lipid while subcutaneous fat decreases. IMAT has been associated with lower muscle strength, power, and quality, chronic inflammation, impaired glucose tolerance, and elevated total cholesterol in older adults. This review focused on trials investigating the role of age, physical activity and diet on IMAT. The studies agreed that IMAT increases with age and seems to be responsive to physical activity, particularly the combination of aerobic and resistance exercise. However, some reported this could occur with or without weight loss, and some reported that high IMAT at baseline may blunt the muscle quality adaptive response to physical training. Larger and longer trials are needed to differentiate the independent or synergistic effects of resistance and/or aerobic training, and obesity and weight loss combined with resistance, aerobic or combination of aerobic and resistance training on IMAT.
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Affiliation(s)
- Debra Lynn Waters
- Department of Medicine and School of Physiotherapy, University of Otago, Dunedin, New Zealand
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18
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Mitogenomic data to study the taxonomy of Antarctic springtail species (Hexapoda: Collembola) and their adaptation to extreme environments. Polar Biol 2019. [DOI: 10.1007/s00300-019-02466-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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19
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Fischer MJ, Horvath G, Krismer M, Gnaiger E, Goebel G, Pesta DH. Evaluation of mitochondrial function in chronic myofascial trigger points - a prospective cohort pilot study using high-resolution respirometry. BMC Musculoskelet Disord 2018; 19:388. [PMID: 30376863 PMCID: PMC6208107 DOI: 10.1186/s12891-018-2307-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 10/17/2018] [Indexed: 11/26/2022] Open
Abstract
Background Myofascial trigger points (MTrPs) are hyperirritable areas in the fascia of the affected muscle, possibly related to mitochondrial impairment. They can result in pain and hypoxic areas within the muscle. This pilot study established a minimally invasive biopsy technique to obtain high-quality MTrP tissue samples to evaluate mitochondrial function via high-resolution respirometry. Secondary objectives included the feasibility and safety of the biopsy procedure. Methods Twenty healthy males participated in this study, 10 with a diagnosis of myofascial pain in the musculus (m.) trapezius MTrP (TTP group) and 10 with a diagnosis of myofascial pain in the m. gluteus medius (GTP group). Each participant had 2 muscle biopsies taken in one session. The affected muscle was biopsied followed by a biopsy from the m. vastus lateralis to be used as a control. Measurements of oxygen consumption were carried out using high-resolution respirometry. Results Mitochondrial respiration was highest in the GTP group compared to the TTP group and the control muscle whereas no differences were observed between the GTP and the control muscle. When normalizing respiration to an internal reference state, there were no differences between muscle groups. None of the participants had hematomas or reported surgical complications. Patient-reported pain was minimal for all 3 groups. All participants reported a low procedural burden. Conclusions This pilot study used a safe and minimally invasive technique for obtaining biopsies from MTrPs suitable for high-resolution respirometry analysis of mitochondrial function. The results suggest that there are no qualitative differences in mitochondrial function of MTrPs of the trapezius and gluteus medius muscles compared to the vastus lateralis control muscle, implying that alterations of mitochondrial function do not appear to have a role in the development of MTrPs. Trial registration Registered as No. 20131128–850 at the Coordinating Center for Clinical Studies of the Medical University of Innsbruck, trial registration date: 28th November 2013 and retrospectively registered on 11th of October 2018 at ClinicalTrials.gov with the ID NCT03704311.
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Affiliation(s)
- Michael J Fischer
- Vamed Rehabilitation Center Kitzbuehel, Kitzbuehel, Austria.,Department of Rehabilitation Medicine, Hanover Medical School, Hanover, Germany.,Department of Orthopedics, Medical University Innsbruck, Innsbruck, Austria
| | - Gergo Horvath
- Department of Medical Biochemistry, Semmelweis University, Budapest, Hungary
| | - Martin Krismer
- Department of Orthopedics, Medical University Innsbruck, Innsbruck, Austria
| | - Erich Gnaiger
- D. Swarovski Research Laboratory, Department of Visceral, Transplant and Thoracic Surgery, Medical University Innsbruck, Innsbruck, Austria
| | - Georg Goebel
- Department of Medical Statistics, Informatics and Health Economics, Medical University Innsbruck, Innsbruck, Austria
| | - Dominik H Pesta
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research, Heinrich-Heine-University, Düsseldorf, Germany. .,German Center for Diabetes Research (DZD), München-Neuherberg, Germany. .,Department of Sport Science, University of Innsbruck, Innsbruck, Austria.
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Hunter GR, Moellering DR, Carter SJ, Gower BA, Bamman MM, Hornbuckle LM, Plaisance EP, Fisher G. Potential Causes of Elevated REE after High-Intensity Exercise. Med Sci Sports Exerc 2018; 49:2414-2421. [PMID: 28737531 DOI: 10.1249/mss.0000000000001386] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
INTRODUCTION Resting energy expenditure (REE) increases after an intense exercise; however, little is known concerning mechanisms. PURPOSE The purpose of this study was to determine effects of a single bout of moderate-intensity continuous (MIC) aerobic exercise, or high-intensity interval (HII) exercise on REE under energy balance conditions. METHODS Thirty-three untrained premenopausal women were evaluated at baseline, after 8-16 wk of training, 22 h after either MIC (50% peak V˙O2) or HII (84% peak V˙O2). Participants were in a room calorimeter during and after the exercise challenge. Food intake was adjusted to obtain energy balance across 23 h. REE was measured after 22 h after all conditions. Twenty-three-hour urine norepinephrine concentration and serum creatine kinase activity (CrKact) were obtained. Muscle biopsies were obtained in a subset of 15 participants to examine muscle mitochondrial state 2, 3, and 4 fat oxidation. RESULTS REE was increased 22 h after MIC (64 ± 119 kcal) and HII (103 ± 137 kcal). Markers of muscle damage (CrKact) increased after HII (9.6 ± 25.5 U·L) and MIC (22.2 ± 22.8 U·L), whereas sympathetic tone (urine norepinephrine) increased after HII (1.1 ± 10.6 ng·mg). Uncoupled phosphorylation (states 2 and 4) fat oxidation were related to REE (r = 0.65 and r = 0.55, respectively); however, neither state 2 nor state 4 fat oxidation increased after MIC or HII. REE was not increased after 8 wk of aerobic training when exercise was restrained for 60 h. CONCLUSIONS Under energy balance conditions, REE increased 22 h after both moderate-intensity and high-intensity exercise. Exercise-induced muscle damage/repair and increased sympathetic tone may contribute to increased REE, whereas uncoupled phosphorylation does not. These results suggest that moderate- to high-intensity exercise may be valuable for increasing energy expenditure for at least 22 h after the exercise.
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Affiliation(s)
- Gary R Hunter
- 1Department of Human Studies, University of Alabama at Birmingham, Birmingham, AL; 2Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL; 3Diabetes Research Center Bioanalytical Redox Biology (BARB) Core, University of Alabama at Birmingham, Birmingham, AL; 4Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL; and 5Department of Kinesiology, Recreation, and Sport Studies, University of Tennessee, Knoxville, TN
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Payne S, Macintosh A, Stock J. Body size and body composition effects on heat loss from the hands during severe cold exposure. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2018; 166:313-322. [PMID: 29430626 DOI: 10.1002/ajpa.23432] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 01/22/2018] [Accepted: 01/23/2018] [Indexed: 02/05/2023]
Abstract
OBJECTIVES This study investigated the influence of body size and composition on maintaining hand temperature during severe cold exposure. The hand's high surface area-to-volume ratio predisposes the hand to heat loss, increasing the risk of cold injury and even hypothermia, which are major selective pressures in cold environments. While vasoregulation may reduce heat loss from the hand, the effect of body form, tissue thermogenesis, and body insulation on heat loss is unknown. MATERIALS AND METHODS Thermal imaging was used to determine heat loss during a 3-min ice-water hand immersion test carried out on 114 volunteers (female = 63, male = 51). Established anthropometric measures were used to quantify body size, and bioelectrical impedance analysis determined skeletal muscle and fat mass. RESULTS Skeletal muscle mass relative to body mass was a highly significant predictor of heat loss, while body mass, fat mass, and stature were not. Body composition and body size had little to no significant influence during rewarming after immersion. DISCUSSION The thermogenic properties of muscle mass support maintenance of hand temperature during severe cold exposure. The findings here suggest that muscular individuals are less susceptible to heat loss and cold injury, and may be better at manual tasks in cold conditions than nonmuscular individuals.
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Affiliation(s)
- Stephanie Payne
- PAVE Research Group, Department of Archaeology, University of Cambridge, Cambridgeshire, CB2 3EX, United Kingdom
| | - Alison Macintosh
- PAVE Research Group, Department of Archaeology, University of Cambridge, Cambridgeshire, CB2 3EX, United Kingdom
| | - Jay Stock
- PAVE Research Group, Department of Archaeology, University of Cambridge, Cambridgeshire, CB2 3EX, United Kingdom.,Department of Anthropology, University of Western Ontario, London, Ontario, N6A 5C2, Canada
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High-Resolution FluoRespirometry and OXPHOS Protocols for Human Cells, Permeabilized Fibers from Small Biopsies of Muscle, and Isolated Mitochondria. Methods Mol Biol 2018; 1782:31-70. [PMID: 29850993 DOI: 10.1007/978-1-4939-7831-1_3] [Citation(s) in RCA: 123] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Protocols for High-Resolution FluoRespirometry of intact cells, permeabilized cells, permeabilized muscle fibers, isolated mitochondria, and tissue homogenates offer sensitive diagnostic tests of integrated mitochondrial function using standard cell culture techniques, small needle biopsies of muscle, and mitochondrial preparation methods. Multiple substrate-uncoupler-inhibitor titration (SUIT) protocols for analysis of oxidative phosphorylation (OXPHOS) improve our understanding of mitochondrial respiratory control and the pathophysiology of mitochondrial diseases. Respiratory states are defined in functional terms to account for the network of metabolic interactions in complex SUIT protocols with stepwise modulation of coupling control and electron transfer pathway states. A regulated degree of intrinsic uncoupling is a hallmark of oxidative phosphorylation, whereas pathological and toxicological dyscoupling is evaluated as a mitochondrial defect. The noncoupled state of maximum respiration is experimentally induced by titration of established uncouplers (CCCP, FCCP, DNP) to collapse the protonmotive force across the mitochondrial inner membrane and measure the electron transfer (ET) capacity (open-circuit operation of respiration). Intrinsic uncoupling and dyscoupling are evaluated as the flux control ratio between non-phosphorylating LEAK respiration (electron flow coupled to proton pumping to compensate for proton leaks) and ET capacity. If OXPHOS capacity (maximally ADP-stimulated O2 flux) is less than ET capacity, the phosphorylation pathway contributes to flux control. Physiological substrate combinations supporting the NADH and succinate pathway are required to reconstitute tricarboxylic acid cycle function. This supports maximum ET and OXPHOS capacities, due to the additive effect of multiple electron supply pathways converging at the Q-junction. ET pathways with electron entry separately through NADH (pyruvate and malate or glutamate and malate) or succinate (succinate and rotenone) restrict ET capacity and artificially enhance flux control upstream of the Q-cycle, providing diagnostic information on specific ET-pathway branches. O2 concentration is maintained above air saturation in protocols with permeabilized muscle fibers to avoid experimental O2 limitation of respiration. Standardized two-point calibration of the polarographic oxygen sensor (static sensor calibration), calibration of the sensor response time (dynamic sensor calibration), and evaluation of instrumental background O2 flux (systemic flux compensation) provide the unique experimental basis for high accuracy of quantitative results and quality control in High-Resolution FluoRespirometry.
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Tueller DJ, Harley JS, Hancock CR. Effects of curcumin and ursolic acid on the mitochondrial coupling efficiency and hydrogen peroxide emission of intact skeletal myoblasts. Biochem Biophys Res Commun 2017; 492:368-372. [PMID: 28847726 DOI: 10.1016/j.bbrc.2017.08.101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 08/25/2017] [Indexed: 11/17/2022]
Abstract
Curcumin may improve blood glucose management, but the mechanism is not fully established. We demonstrated that curcumin (40 μM) reduced the mitochondrial coupling efficiency (percentage of oxygen consumption coupled to ATP synthesis) of intact skeletal muscle cells. A 30-minute pretreatment with curcumin reduced mitochondrial coupling efficiency by 17.0 ± 0.4% relative to vehicle (p < 0.008). Curcumin pretreatment also decreased the rate of hydrogen peroxide emission by 43 ± 13% compared to vehicle (p < 0.05). Analysis of cell respiration in the presence of curcumin revealed a 40 ± 4% increase in the rate of oxygen consumption upon curcumin administration (p < 0.05 compared to vehicle). No difference in mitochondrial coupling efficiency was observed between vehicle- and curcumin-pretreated cells after permeabilization of cell membranes (p > 0.7). The interaction between curcumin and ursolic acid, another natural compound that may improve blood glucose management, was also examined. Pretreatment with ursolic acid (0.12 μM) increased the mitochondrial coupling efficiency of intact cells by 4.1 ± 1.1% relative to vehicle (p < 0.008) and attenuated the effect of curcumin when the two compounds were used in combination. The observed changes to mitochondrial coupling efficiency and hydrogen peroxide emission were consistent with the established effects of curcumin on blood glucose control. Our findings also show that changes to mitochondrial coupling efficiency after curcumin pretreatment may go undetected unless cells are assessed in the intact condition.
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Affiliation(s)
- Daniel J Tueller
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, UT 84602, USA
| | - Jackson S Harley
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, UT 84602, USA
| | - Chad R Hancock
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, UT 84602, USA.
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Kake-Guena S, Touisse K, Warren B, Scott K, Dufresne F, Blier P, Lemieux H. Temperature-related differences in mitochondrial function among clones of the cladoceran Daphnia pulex. J Therm Biol 2017; 69:23-31. [DOI: 10.1016/j.jtherbio.2017.05.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 05/10/2017] [Accepted: 05/20/2017] [Indexed: 10/19/2022]
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Towarnicki SG, Ballard JWO. Drosophila mitotypes determine developmental time in a diet and temperature dependent manner. JOURNAL OF INSECT PHYSIOLOGY 2017; 100:133-139. [PMID: 28619466 DOI: 10.1016/j.jinsphys.2017.06.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 06/05/2017] [Accepted: 06/07/2017] [Indexed: 06/07/2023]
Abstract
It is well known that specific mitochondrial (mt) DNA mutations can reduce organismal fitness and influence mitochondrial-nuclear interactions. However, determining specific mtDNA mutations that are beneficial has been elusive. In this study, we vary the diet and environmental temperature to study larval development time of two Drosophila melanogaster mitotypes (Alstonville and Dahomey), in two nuclear genetic backgrounds, and investigate developmental differences through weight, feeding rate, and movement. To manipulate the diet, we utilize the nutritional geometric framework to manipulate isocaloric diets of differing macronutrient ratios (1:2 and 1:16 protein: carbohydrate (P:C) ratios) and raise flies at three temperatures (19°C, 23°C and 27°C). Larvae with Dahomey mtDNA develop more slowly than Alstonville when fed the 1:2 P:C diet at all temperatures and developed more quickly when fed the 1:16 P:C diet at 23°C and 27°C. We determined that Dahomey larvae eat more, move less, and weigh more than Alstonville larvae when raised on the 1:16 P:C diet and that these physiological responses are modified by temperature. We suggest that 1 (or more) of 4 mtDNA changes is likely responsible for the observed effects and posit the mtDNA changes moderate a physiological trade-off between consumption and foraging.
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Affiliation(s)
- Samuel G Towarnicki
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia.
| | - J William O Ballard
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia.
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Abstract
The Himalayan Sherpas, a human population of Tibetan descent, are highly adapted to life in the hypobaric hypoxia of high altitude. Mechanisms involving enhanced tissue oxygen delivery in comparison to Lowlander populations have been postulated to play a role in such adaptation. Whether differences in tissue oxygen utilization (i.e., metabolic adaptation) underpin this adaptation is not known, however. We sought to address this issue, applying parallel molecular, biochemical, physiological, and genetic approaches to the study of Sherpas and native Lowlanders, studied before and during exposure to hypobaric hypoxia on a gradual ascent to Mount Everest Base Camp (5,300 m). Compared with Lowlanders, Sherpas demonstrated a lower capacity for fatty acid oxidation in skeletal muscle biopsies, along with enhanced efficiency of oxygen utilization, improved muscle energetics, and protection against oxidative stress. This adaptation appeared to be related, in part, to a putatively advantageous allele for the peroxisome proliferator-activated receptor A (PPARA) gene, which was enriched in the Sherpas compared with the Lowlanders. Our findings suggest that metabolic adaptations underpin human evolution to life at high altitude, and could have an impact upon our understanding of human diseases in which hypoxia is a feature.
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Miller B, Hamilton K, Boushel R, Williamson K, Laner V, Gnaiger E, Davis M. Mitochondrial respiration in highly aerobic canines in the non-raced state and after a 1600-km sled dog race. PLoS One 2017; 12:e0174874. [PMID: 28445477 PMCID: PMC5405936 DOI: 10.1371/journal.pone.0174874] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2016] [Accepted: 03/16/2017] [Indexed: 11/23/2022] Open
Abstract
At the annual Iditarod Race, Alaskan Huskies repeatedly run for up to 8 hours at 16 km/h to complete 1600 km. We previously demonstrated high rates of mitochondrial protein synthesis in Alaskan Huskies, which we suspected allowed rapid remodeling of mitochondrial proteins in response to energetic stress. The purpose of this study was to examine mitochondrial respiration in permeabilized skeletal muscle fibers of Alaskan Huskies in the offseason (Non-raced) and following the 1600 km Iditarod Sled Dog Race (Raced). We hypothesized that compared to Non-raced Huskies, raced Huskies that completed a 1600 km race would have greater mitochondrial respiratory capacities, and improvements in capacities of oxidative phosphorylation (OXPHOS) based on NADH-generating substrates as compared to fatty acids. Using high-resolution respirometry (HRR) we investigated the respiration of permeabilized muscle fibers from Alaskan Huskies. Maximum capacities were 254±26 pmol.s-1.mg-1 for OXPHOS (coupled, P) and 254±37 pmol.s-1.mg-1 for the electron transfer system (ETS; non-coupled, E). After racing respiratory capacities from NADH-linked substrates, but not fat-derived substrates increased. Finally, the OXPHOS to ETS capacity ratio (P/E) increased after racing from 0.90±0.03 to 0.97±0.02. From our previous studies and the current study, we conclude that Alaskan Huskies maintain high mitochondrial protein turnover to facilitate rapid adaptation to environmental extremes and energetic challenges.
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Affiliation(s)
- Benjamin Miller
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, United States of America
| | - Karyn Hamilton
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, United States of America
| | - Robert Boushel
- School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
| | | | | | - Erich Gnaiger
- Department of Visceral, Transplant and Thoracic Surgery, D. Swarvoski Research Laboratory, Medical University of Innsbruck, Innsbruck, Austria
| | - Michael Davis
- Department of Physiological Sciences, Oklahoma State University, Stillwater, Oklahoma, United States of America
- * E-mail:
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Leo E, Kunz KL, Schmidt M, Storch D, Pörtner HO, Mark FC. Mitochondrial acclimation potential to ocean acidification and warming of Polar cod ( Boreogadus saida) and Atlantic cod ( Gadus morhua). Front Zool 2017; 14:21. [PMID: 28416963 PMCID: PMC5391599 DOI: 10.1186/s12983-017-0205-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 03/30/2017] [Indexed: 12/20/2022] Open
Abstract
Background Ocean acidification and warming are happening fast in the Arctic but little is known about the effects of ocean acidification and warming on the physiological performance and survival of Arctic fish. Results In this study we investigated the metabolic background of performance through analyses of cardiac mitochondrial function in response to control and elevated water temperatures and PCO2 of two gadoid fish species, Polar cod (Boreogadus saida), an endemic Arctic species, and Atlantic cod (Gadus morhua), which is a temperate to cold eurytherm and currently expanding into Arctic waters in the wake of ocean warming. We studied their responses to the above-mentioned drivers and their acclimation potential through analysing the cardiac mitochondrial function in permeabilised cardiac muscle fibres after 4 months of incubation at different temperatures (Polar cod: 0, 3, 6, 8 °C and Atlantic cod: 3, 8, 12, 16 °C), combined with exposure to present (400μatm) and year 2100 (1170μatm) levels of CO2. OXPHOS, proton leak and ATP production efficiency in Polar cod were similar in the groups acclimated at 400μatm and 1170μatm of CO2, while incubation at 8 °C evoked increased proton leak resulting in decreased ATP production efficiency and decreased Complex IV capacity. In contrast, OXPHOS of Atlantic cod increased with temperature without compromising the ATP production efficiency, whereas the combination of high temperature and high PCO2 depressed OXPHOS and ATP production efficiency. Conclusions Polar cod mitochondrial efficiency decreased at 8 °C while Atlantic cod mitochondria were more resilient to elevated temperature; however, this resilience was constrained by high PCO2. In line with its lower habitat temperature and higher degree of stenothermy, Polar cod has a lower acclimation potential to warming than Atlantic cod.
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Affiliation(s)
- Elettra Leo
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Integrative Ecophysiology, Am Handelshafen 12, D-27570 Bremerhaven, Germany.,University of Bremen, Fachbereich 2, NW 2/Leobener Strasse, D-28359 Bremen, Germany
| | - Kristina L Kunz
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Integrative Ecophysiology, Am Handelshafen 12, D-27570 Bremerhaven, Germany.,University of Bremen, Fachbereich 2, NW 2/Leobener Strasse, D-28359 Bremen, Germany.,Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bentho-Pelagic Processes, Am Alten Hafen 26, D-27568 Bremerhaven, Germany
| | - Matthias Schmidt
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Integrative Ecophysiology, Am Handelshafen 12, D-27570 Bremerhaven, Germany.,University of Bremen, Fachbereich 2, NW 2/Leobener Strasse, D-28359 Bremen, Germany
| | - Daniela Storch
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Integrative Ecophysiology, Am Handelshafen 12, D-27570 Bremerhaven, Germany
| | - Hans-O Pörtner
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Integrative Ecophysiology, Am Handelshafen 12, D-27570 Bremerhaven, Germany.,University of Bremen, Fachbereich 2, NW 2/Leobener Strasse, D-28359 Bremen, Germany
| | - Felix C Mark
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Integrative Ecophysiology, Am Handelshafen 12, D-27570 Bremerhaven, Germany
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Dahlke FT, Leo E, Mark FC, Pörtner HO, Bickmeyer U, Frickenhaus S, Storch D. Effects of ocean acidification increase embryonic sensitivity to thermal extremes in Atlantic cod, Gadus morhua. GLOBAL CHANGE BIOLOGY 2017; 23:1499-1510. [PMID: 27718513 DOI: 10.1111/gcb.13527] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 09/26/2016] [Accepted: 09/30/2016] [Indexed: 06/06/2023]
Abstract
Thermal tolerance windows serve as a powerful tool for estimating the vulnerability of marine species and their life stages to increasing temperature means and extremes. However, it remains uncertain to which extent additional drivers, such as ocean acidification, modify organismal responses to temperature. This study investigated the effects of CO2 -driven ocean acidification on embryonic thermal sensitivity and performance in Atlantic cod, Gadus morhua, from the Kattegat. Fertilized eggs were exposed to factorial combinations of two PCO2 conditions (400 μatm vs. 1100 μatm) and five temperature treatments (0, 3, 6, 9 and 12 °C), which allow identifying both lower and upper thermal tolerance thresholds. We quantified hatching success, oxygen consumption (MO2 ) and mitochondrial functioning of embryos as well as larval morphometrics at hatch and the abundance of acid-base-relevant ionocytes on the yolk sac epithelium of newly hatched larvae. Hatching success was high under ambient spawning conditions (3-6 °C), but decreased towards both cold and warm temperature extremes. Elevated PCO2 caused a significant decrease in hatching success, particularly at cold (3 and 0 °C) and warm (12 °C) temperatures. Warming imposed limitations to MO2 and mitochondrial capacities. Elevated PCO2 stimulated MO2 at cold and intermediate temperatures, but exacerbated warming-induced constraints on MO2 , indicating a synergistic interaction with temperature. Mitochondrial functioning was not affected by PCO2 . Increased MO2 in response to elevated PCO2 was paralleled by reduced larval size at hatch. Finally, ionocyte abundance decreased with increasing temperature, but did not differ between PCO2 treatments. Our results demonstrate increased thermal sensitivity of cod embryos under future PCO2 conditions and suggest that acclimation to elevated PCO2 requires reallocation of limited resources at the expense of embryonic growth. We conclude that ocean acidification constrains the thermal performance window of embryos, which has important implication for the susceptibility of cod to projected climate change.
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Affiliation(s)
- Flemming T Dahlke
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, 27570, Bremerhaven, Germany
- University of Bremen, NW 2 Loebener Str., 28359, Bremen, Germany
| | - Elettra Leo
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, 27570, Bremerhaven, Germany
- University of Bremen, NW 2 Loebener Str., 28359, Bremen, Germany
| | - Felix C Mark
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, 27570, Bremerhaven, Germany
| | - Hans-Otto Pörtner
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, 27570, Bremerhaven, Germany
- University of Bremen, NW 2 Loebener Str., 28359, Bremen, Germany
| | - Ulf Bickmeyer
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, 27570, Bremerhaven, Germany
| | - Stephan Frickenhaus
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, 27570, Bremerhaven, Germany
- Hochschule Bremerhaven, An der Karlstadt 8, 27568, Bremerhaven, Germany
| | - Daniela Storch
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, 27570, Bremerhaven, Germany
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Booth FW. Muscle adaptation to exercise: New Saltin's paradigms. Scand J Med Sci Sports 2016; 25 Suppl 4:49-52. [PMID: 26589117 DOI: 10.1111/sms.12595] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/29/2015] [Indexed: 01/15/2023]
Abstract
The title assigned for my lecture at the Saltin Symposium was "Muscle adaptation to exercise: new paradigms." The title's topic made me remember that some of Saltin's paradigms for his development of a novel exercise model were either originated by him or modified by him from existing information. Therefore, I deemed it would be instructive for future generations to consider one facet of his 54-year career--human exercise models. I arbitrarily selected to share five examples of new paradigm models initiated by Saltin. They are: bed rest; arms vs legs; one leg vs the other leg; myokine communication from skeletal muscle to other organs/tissues; and 42-day cross-country skiing expedition. I arbitrarily selected the above as examples of novel approaches that he used to the study humans during maximal endurance exercise. Noteworthy though is that Saltin's lifetime demeanor, itself, is a model for other scientists. In final analysis, the world is richer due to his passion to study humans to advance medical science by uncovering mechanisms as to how the human body is constructed to perform endurance types of exercise at maximal intensities and durations.
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Affiliation(s)
- F W Booth
- Department of Biomedical Sciences, University of Missouri, Columbia, Missouri, USA
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Calbet JAL, González-Alonso J, Helge JW, Søndergaard H, Munch-Andersen T, Saltin B, Boushel R. Central and peripheral hemodynamics in exercising humans: leg vs arm exercise. Scand J Med Sci Sports 2016; 25 Suppl 4:144-57. [PMID: 26589128 DOI: 10.1111/sms.12604] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/04/2015] [Indexed: 12/22/2022]
Abstract
In humans, arm exercise is known to elicit larger increases in arterial blood pressure (BP) than leg exercise. However, the precise regulation of regional vascular conductances (VC) for the distribution of cardiac output with exercise intensity remains unknown. Hemodynamic responses were assessed during incremental upright arm cranking (AC) and leg pedalling (LP) to exhaustion (Wmax) in nine males. Systemic VC, peak cardiac output (Qpeak) (indocyanine green) and stroke volume (SV) were 18%, 23%, and 20% lower during AC than LP. The mean BP, the rate-pressure product and the associated myocardial oxygen demand were 22%, 12%, and 14% higher, respectively, during maximal AC than LP. Trunk VC was reduced to similar values at Wmax. At Wmax, muscle mass-normalized VC and fractional O2 extraction were lower in the arm than the leg muscles. However, this was compensated for during AC by raising perfusion pressure to increase O2 delivery, allowing a similar peak VO2 per kg of muscle mass in both extremities. In summary, despite a lower Qpeak during arm cranking the cardiovascular strain is much higher than during leg pedalling. The adjustments of regional conductances during incremental exercise to exhaustion depend mostly on the relative intensity of exercise and are limb-specific.
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Affiliation(s)
- J A L Calbet
- Department of Physical Education and Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, Canary Islands, Spain.,The Copenhagen Muscle Research Centre, Rigshospitalet, Copenhagen N, Denmark
| | - J González-Alonso
- The Copenhagen Muscle Research Centre, Rigshospitalet, Copenhagen N, Denmark.,Centre for Sports Medicine and Human Performance, Brunel University London, Uxbridge, UK
| | - J W Helge
- The Copenhagen Muscle Research Centre, Rigshospitalet, Copenhagen N, Denmark.,Centre for Healthy Ageing, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - H Søndergaard
- The Copenhagen Muscle Research Centre, Rigshospitalet, Copenhagen N, Denmark
| | - T Munch-Andersen
- The Copenhagen Muscle Research Centre, Rigshospitalet, Copenhagen N, Denmark
| | - B Saltin
- The Copenhagen Muscle Research Centre, Rigshospitalet, Copenhagen N, Denmark
| | - R Boushel
- The Copenhagen Muscle Research Centre, Rigshospitalet, Copenhagen N, Denmark.,School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
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Morales-Alamo D, Calbet JAL. AMPK signaling in skeletal muscle during exercise: Role of reactive oxygen and nitrogen species. Free Radic Biol Med 2016; 98:68-77. [PMID: 26804254 DOI: 10.1016/j.freeradbiomed.2016.01.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2015] [Revised: 01/15/2016] [Accepted: 01/18/2016] [Indexed: 12/17/2022]
Abstract
Reactive oxygen and nitrogen species (RONS) are generated during exercise depending on intensity, duration and training status. A greater amount of RONS is released during repeated high-intensity sprint exercise and when the exercise is performed in hypoxia. By activating adenosine monophosphate-activated kinase (AMPK), RONS play a critical role in the regulation of muscle metabolism but also in the adaptive responses to exercise training. RONS may activate AMPK by direct an indirect mechanisms. Directly, RONS may activate or deactivate AMPK by modifying RONS-sensitive residues of the AMPK-α subunit. Indirectly, RONS may activate AMPK by reducing mitochondrial ATP synthesis, leading to an increased AMP:ATP ratio and subsequent Thr(172)-AMPK phosphorylation by the two main AMPK kinases: LKB1 and CaMKKβ. In presence of RONS the rate of Thr(172)-AMPK dephosphorylation is reduced. RONS may activate LKB1 through Sestrin2 and SIRT1 (NAD(+)/NADH.H(+)-dependent deacetylase). RONS may also activate CaMKKβ by direct modification of RONS sensitive motifs and, indirectly, by activating the ryanodine receptor (Ryr) to release Ca(2+). Both too high (hypoxia) and too low (ingestion of antioxidants) RONS levels may lead to Ser(485)-AMPKα1/Ser(491)-AMPKα2 phosphorylation causing inhibition of Thr(172)-AMPKα phosphorylation. Exercise training increases muscle antioxidant capacity. When the same high-intensity training is applied to arm and leg muscles, arm muscles show signs of increased oxidative stress and reduced mitochondrial biogenesis, which may be explained by differences in RONS-sensing mechanisms and basal antioxidant capacities between arm and leg muscles. Efficient adaptation to exercise training requires optimal exposure to pulses of RONS. Inappropriate training stimulus may lead to excessive RONS formation, oxidative inactivation of AMPK and reduced adaptation or even maladaptation. Theoretically, exercise programs should be designed taking into account the intrinsic properties of different skeletal muscles, the specific RONS induction and the subsequent signaling responses.
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Affiliation(s)
- David Morales-Alamo
- Department of Physical Education, University of Las Palmas de Gran Canaria, Campus Universitario de Tafira s/n, Las Palmas de Gran Canaria, Canary Island, Spain; Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, Campus Universitario de Tafira s/n, Las Palmas de Gran Canaria, Canary Island, Spain.
| | - Jose A L Calbet
- Department of Physical Education, University of Las Palmas de Gran Canaria, Campus Universitario de Tafira s/n, Las Palmas de Gran Canaria, Canary Island, Spain; Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, Campus Universitario de Tafira s/n, Las Palmas de Gran Canaria, Canary Island, Spain
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