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Kolodziej F, McDonagh B, Burns N, Goljanek-Whysall K. MicroRNAs as the Sentinels of Redox and Hypertrophic Signalling. Int J Mol Sci 2022; 23:ijms232314716. [PMID: 36499053 PMCID: PMC9737617 DOI: 10.3390/ijms232314716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 11/22/2022] [Accepted: 11/23/2022] [Indexed: 11/26/2022] Open
Abstract
Oxidative stress and inflammation are associated with skeletal muscle function decline with ageing or disease or inadequate exercise and/or poor diet. Paradoxically, reactive oxygen species and inflammatory cytokines are key for mounting the muscular and systemic adaptive responses to endurance and resistance exercise. Both ageing and lifestyle-related metabolic dysfunction are strongly linked to exercise redox and hypertrophic insensitivity. The adaptive inability and consequent exercise intolerance may discourage people from physical training resulting in a vicious cycle of under-exercising, energy surplus, chronic mitochondrial stress, accelerated functional decline and increased susceptibility to serious diseases. Skeletal muscles are malleable and dynamic organs, rewiring their metabolism depending on the metabolic or mechanical stress resulting in a specific phenotype. Endogenous RNA silencing molecules, microRNAs, are regulators of these metabolic/phenotypic shifts in skeletal muscles. Skeletal muscle microRNA profiles at baseline and in response to exercise have been observed to differ between adult and older people, as well as trained vs. sedentary individuals. Likewise, the circulating microRNA blueprint varies based on age and training status. Therefore, microRNAs emerge as key regulators of metabolic health/capacity and hormetic adaptability. In this narrative review, we summarise the literature exploring the links between microRNAs and skeletal muscle, as well as systemic adaptation to exercise. We expand a mathematical model of microRNA burst during adaptation to exercise through supporting data from the literature. We describe a potential link between the microRNA-dependent regulation of redox-signalling sensitivity and the ability to mount a hypertrophic response to exercise or nutritional cues. We propose a hypothetical model of endurance exercise-induced microRNA "memory cloud" responsible for establishing a landscape conducive to aerobic as well as anabolic adaptation. We suggest that regular aerobic exercise, complimented by a healthy diet, in addition to promoting mitochondrial health and hypertrophic/insulin sensitivity, may also suppress the glycolytic phenotype and mTOR signalling through miRNAs which in turn promote systemic metabolic health.
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Affiliation(s)
- Filip Kolodziej
- Department of Physiology, School of Medicine, CMNHS, University of Galway, H91TK33 Galway, Ireland
| | - Brian McDonagh
- Department of Physiology, School of Medicine, CMNHS, University of Galway, H91TK33 Galway, Ireland
| | - Nicole Burns
- Department of Physiology, School of Medicine, CMNHS, University of Galway, H91TK33 Galway, Ireland
| | - Katarzyna Goljanek-Whysall
- Department of Physiology, School of Medicine, CMNHS, University of Galway, H91TK33 Galway, Ireland
- Institute of Life Course and Medical Science, University of Liverpool, Liverpool L69 3BX, UK
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Lopez Kolkovsky AL, Marty B, Giacomini E, Meyerspeer M, Carlier PG. Repeatability of multinuclear interleaved acquisitions with nuclear Overhauser enhancement effect in dynamic experiments in the calf muscle at 3T. Magn Reson Med 2021; 86:115-130. [PMID: 33565187 DOI: 10.1002/mrm.28684] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 12/23/2020] [Accepted: 12/23/2020] [Indexed: 02/01/2023]
Abstract
PURPOSE To evaluate the repeatability of multinuclear interleaved 1 H/31 P NMR dynamic acquisitions in skeletal muscle and the impact of nuclear Overhauser enhancement (nOe) on the 31 P results at 3T in exercise-recovery and ischemia-hyperemia paradigms. METHODS A 1 H/31 P interleaved pulse sequence was used to measure every 2.5 s a perfusion-weighted image, a T 2 ∗ map, a 31 P spectrum and 32 1 H spectra sensitive to deoxymyoglobin. 21 subjects performed a plantar flexion exercise and after recovery underwent an 8-min lower leg ischemia. The procedure was repeated in visit 2 with 12 subjects. An additional exercise bout without 1 H excitation was appended to visit 1. Individual 1 H RF pulse nOe was measured at rest in every visit. RESULTS Repeatability scores (coefficient of variation, Bland-Altman analysis) were similar to those found in the literature using similar mono-nuclear acquisitions. |Pi]/[PCr], pH drop, creatine rephosphorylation rate (τPCr ), maximum perfusion, time to peak perfusion, and blood flow post-exercise showed high reliability (intraclass correlation coefficient > 0.7), whereas hemodynamic results from reactive hyperemia showed higher repeatability. After accounting for nOe, which increased Pi and PCr signal-to-noise ratio by 30%, no differences in 31 P results were observed between interleaved and 31 P MRS-only acquisitions. τPCr was unaffected by nOe. CONCLUSION The method shows good repeatability for both paradigms while simultaneously providing multiple dynamic data sets on a clinical scanner. The nOe effects were accounted for on a per-subject and per-visit basis using a short 31 P reference scan. This multiparametric approach has a multitude of applications for the study of oxygen utilization and ATP turnover in the muscle.
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Affiliation(s)
- Alfredo L Lopez Kolkovsky
- NMR Laboratory, Neuromuscular Investigation Center, Institute of Myology, Paris, France.,NMR Laboratory, CEA, DRF, IBFJ, MIRCen, Paris, France
| | - Benjamin Marty
- NMR Laboratory, Neuromuscular Investigation Center, Institute of Myology, Paris, France.,NMR Laboratory, CEA, DRF, IBFJ, MIRCen, Paris, France
| | - Eric Giacomini
- NMR Laboratory, Neuromuscular Investigation Center, Institute of Myology, Paris, France
| | - Martin Meyerspeer
- High Field MR Center, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Pierre G Carlier
- NMR Laboratory, Neuromuscular Investigation Center, Institute of Myology, Paris, France.,NMR Laboratory, CEA, DRF, IBFJ, MIRCen, Paris, France
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Kumar D, Nanga RPR, Thakuri D, Wilson N, Cember A, Martin ML, Zhu D, Shinohara RT, Qin Q, Hariharan H, Reddy R. Recovery kinetics of creatine in mild plantar flexion exercise using 3D creatine CEST imaging at 7 Tesla. Magn Reson Med 2020; 85:802-817. [PMID: 32820572 DOI: 10.1002/mrm.28463] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 07/08/2020] [Accepted: 07/14/2020] [Indexed: 11/06/2022]
Abstract
PURPOSE Two-dimensional creatine CEST (2D-CrCEST), with a slice thickness of 10-20 mm and temporal resolution (τRes ) of about 30 seconds, has previously been shown to capture the creatine-recovery kinetics in healthy controls and in patients with abnormal creatine-kinase kinetics following the mild plantar flexion exercise. Since the distribution of disease burden may vary across the muscle length for many musculoskeletal disorders, there is a need to increase coverage in the slice-encoding direction. Here, we demonstrate the feasibility of 3D-CrCEST with τRes of about 30 seconds, and propose an improved voxel-wise B 1 + -calibration approach for CrCEST. METHODS The current 7T study with enrollment of 5 volunteers involved collecting the baseline CrCEST imaging for the first 2 minutes, followed by 2 minutes of plantar flexion exercise and then 8 minutes of postexercise CrCEST imaging, to detect the temporal evolution of creatine concentration following exercise. RESULTS Very good repeatability of 3D-CrCEST findings for activated muscle groups on an intraday and interday basis was established, with coefficient of variance of creatine recovery constants (τCr ) being 7%-15.7%, 7.5%, and 5.8% for lateral gastrocnemius, medial gastrocnemius, and peroneus longus, respectively. We also established a good intraday and interday scan repeatability for 3D-CrCEST and also showed good correspondence between τCr measurements using 2D-CrCEST and 3D-CrCEST acquisitions. CONCLUSION In this study, we demonstrated for the first time the feasibility and the repeatability of the 3D-CrCEST method in calf muscle with improved B 1 + correction to measure creatine-recovery kinetics within a large 3D volume of calf muscle.
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Affiliation(s)
- Dushyant Kumar
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | | | - Deepa Thakuri
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Neil Wilson
- Siemens Medical Solutions USA Inc., Malvern, Pennsylvania, USA
| | - Abigail Cember
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Melissa Lynne Martin
- Penn Statistics in Imaging and Visualization Center, Department of Biostatistics and Epidemiology, Perelman School of Medicine, Philadelphia, Pennsylvania, USA
| | - Dan Zhu
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Russell T Shinohara
- Penn Statistics in Imaging and Visualization Center, Department of Biostatistics and Epidemiology, Perelman School of Medicine, Philadelphia, Pennsylvania, USA
| | - Qin Qin
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
| | - Hari Hariharan
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ravinder Reddy
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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4
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Exacerbated metabolic changes in skeletal muscle of sickle cell mice submitted to an acute ischemia-reperfusion paradigm. Clin Sci (Lond) 2018; 132:2103-2115. [PMID: 30185507 DOI: 10.1042/cs20180268] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 08/27/2018] [Accepted: 09/05/2018] [Indexed: 11/17/2022]
Abstract
Sickle cell disease (SCD) is characterized by painful vaso-occlusive crisis. While there are several metabolic abnormalities potentially associated with muscular ischemia-reperfusion cycles that could be harmful in the context of SCD, the metabolic consequences of such events are still unknown. Ten controls (HbAA), thirteen heterozygous (HbAS), and ten homozygous (HbSS) SCD mice were submitted to a standardized protocol of rest-ischemia-reperfusion of the left leg during which adenosine triphosphate, phosphocreatine, and inorganic phosphate concentrations as well as intramuscular pH were measured using phosphorous magnetic resonance spectroscopy (MRS). Forty-eight hours later, skeletal muscles were harvested. Oxidative stress markers were then measured on the tibialis anterior. At the end of the ischemic period, HbSS mice had a lower pH value as compared with the HbAA and HbAS groups (P<0.01). During the reperfusion period, the initial rate of phosphocreatine resynthesis was lower in HbSS mice as compared with HbAA (P<0.05) and HbAS (P<0.01) animals. No significant difference among groups was observed regarding oxidative stress markers. HbSS mice displayed a higher intramuscular acidosis during the ischemic period while their mitochondrial function was impaired as compared with their HbAA and HbAS counterparts. These metabolic abnormalities could worsen the complications related to the pathology of SCD.
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Willis WT, Miranda-Grandjean D, Hudgens J, Willis EA, Finlayson J, De Filippis EA, Zapata Bustos R, Langlais PR, Mielke C, Mandarino LJ. Dominant and sensitive control of oxidative flux by the ATP-ADP carrier in human skeletal muscle mitochondria: Effect of lysine acetylation. Arch Biochem Biophys 2018; 647:93-103. [PMID: 29653079 DOI: 10.1016/j.abb.2018.04.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 03/29/2018] [Accepted: 04/08/2018] [Indexed: 02/01/2023]
Abstract
The adenine nucleotide translocase (ANT) of the mitochondrial inner membrane exchanges ADP for ATP. Mitochondria were isolated from human vastus lateralis muscle (n = 9). Carboxyatractyloside titration of O2 consumption rate (Jo) at clamped [ADP] of 21 μM gave ANT abundance of 0.97 ± 0.14 nmol ANT/mg and a flux control coefficient of 82% ± 6%. Flux control fell to 1% ± 1% at saturating (2 mM) [ADP]. The KmADP for Jo was 32.4 ± 1.8 μM. In terms of the free (-3) ADP anion this KmADP was 12.0 ± 0.7 μM. A novel luciferase-based assay for ATP production gave KmADP of 13.1 ± 1.9 μM in the absence of ATP competition. The free anion KmADP in this case was 2.0 ± 0.3 μM. Targeted proteomic analyses showed significant acetylation of ANT Lysine23 and that ANT1 was the most abundant isoform. Acetylation of Lysine23 correlated positively with KmADP, r = 0.74, P = 0.022. The findings underscore the central role played by ANT in the control of oxidative phosphorylation, particularly at the energy phosphate levels associated with low ATP demand. As predicted by molecular dynamic modeling, ANT Lysine23 acetylation decreased the apparent affinity of ADP for ANT binding.
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Affiliation(s)
- W T Willis
- University of Arizona, College of Medicine, Department of Medicine, 1501 N. Campbell Avenue, P.O. Box 245099, Tucson, AZ 85724-5099, USA.
| | - D Miranda-Grandjean
- Mayo Clinic, Division of Endocrinology, East Shea Boulevard and 134th Street, Scottsdale, AZ 85259, USA.
| | - J Hudgens
- Mayo Clinic, Division of Endocrinology, East Shea Boulevard and 134th Street, Scottsdale, AZ 85259, USA.
| | - E A Willis
- Mayo Clinic, Division of Endocrinology, East Shea Boulevard and 134th Street, Scottsdale, AZ 85259, USA.
| | - J Finlayson
- University of Arizona, College of Medicine, Department of Medicine, 1501 N. Campbell Avenue, P.O. Box 245099, Tucson, AZ 85724-5099, USA.
| | - E A De Filippis
- Mayo Clinic, Division of Endocrinology, East Shea Boulevard and 134th Street, Scottsdale, AZ 85259, USA.
| | - R Zapata Bustos
- University of Arizona, College of Medicine, Department of Medicine, 1501 N. Campbell Avenue, P.O. Box 245099, Tucson, AZ 85724-5099, USA.
| | - P R Langlais
- University of Arizona, College of Medicine, Department of Medicine, 1501 N. Campbell Avenue, P.O. Box 245099, Tucson, AZ 85724-5099, USA.
| | - C Mielke
- Mayo Clinic, Division of Endocrinology, East Shea Boulevard and 134th Street, Scottsdale, AZ 85259, USA.
| | - L J Mandarino
- University of Arizona, College of Medicine, Department of Medicine, 1501 N. Campbell Avenue, P.O. Box 245099, Tucson, AZ 85724-5099, USA.
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Moll K, Gussew A, Hein C, Stutzig N, Reichenbach JR. Combined spiroergometry and 31 P-MRS of human calf muscle during high-intensity exercise. NMR IN BIOMEDICINE 2017; 30:e3723. [PMID: 28340292 DOI: 10.1002/nbm.3723] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 02/07/2017] [Accepted: 02/08/2017] [Indexed: 06/06/2023]
Abstract
Simultaneous measurements of pulmonary oxygen consumption (VO2 ), carbon dioxide exhalation (VCO2 ) and phosphorus magnetic resonance spectroscopy (31 P-MRS) are valuable in physiological studies to evaluate muscle metabolism during specific loads. Therefore, the aim of this study was to adapt a commercially available spirometric device to enable measurements of VO2 and VCO2 whilst simultaneously performing 31 P-MRS at 3 T. Volunteers performed intense plantar flexion of their right calf muscle inside the MR scanner against a pneumatic MR-compatible pedal ergometer. The use of a non-magnetic pneumotachograph and extension of the sampling line from 3 m to 5 m to place the spirometric device outside the MR scanner room did not affect adversely the measurements of VO2 and VCO2 . Response and delay times increased, on average, by at most 0.05 s and 0.79 s, respectively. Overall, we were able to demonstrate a feasible ventilation response (VO2 = 1.05 ± 0.31 L/min; VCO2 = 1.11 ± 0.33 L/min) during the exercise of a single calf muscle, as well as a good correlation between local energy metabolism and muscular acidification (τPCr fast and pH; R2 = 0.73, p < 0.005) and global respiration (τPCr fast and VO2 ; R2 = 0.55, p = 0.01). This provides improved insights into aerobic and anaerobic energy supply during strong muscular performances.
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Affiliation(s)
- K Moll
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany
| | - A Gussew
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany
| | - C Hein
- Ganshorn Medizin Electronic GmbH, Niederlauer, Germany
| | - N Stutzig
- Exercise Science, Institute of Sport and Movement Science, University of Stuttgart, Stuttgart, Germany
| | - J R Reichenbach
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany
- Michael Stifel Center for Data-Driven and Simulation Science Jena, Friedrich Schiller University Jena, Jena, Germany
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7
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Valkovič L, Chmelík M, Krššák M. In-vivo 31P-MRS of skeletal muscle and liver: A way for non-invasive assessment of their metabolism. Anal Biochem 2017; 529:193-215. [PMID: 28119063 PMCID: PMC5478074 DOI: 10.1016/j.ab.2017.01.018] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 01/13/2017] [Accepted: 01/19/2017] [Indexed: 01/18/2023]
Abstract
In addition to direct assessment of high energy phosphorus containing metabolite content within tissues, phosphorus magnetic resonance spectroscopy (31P-MRS) provides options to measure phospholipid metabolites and cellular pH, as well as the kinetics of chemical reactions of energy metabolism in vivo. Even though the great potential of 31P-MR was recognized over 30 years ago, modern MR systems, as well as new, dedicated hardware and measurement techniques provide further opportunities for research of human biochemistry. This paper presents a methodological overview of the 31P-MR techniques that can be used for basic, physiological, or clinical research of human skeletal muscle and liver in vivo. Practical issues of 31P-MRS experiments and examples of potential applications are also provided. As signal localization is essential for liver 31P-MRS and is important for dynamic muscle examinations as well, typical localization strategies for 31P-MR are also described.
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Affiliation(s)
- Ladislav Valkovič
- High-field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria; Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, Oxford, United Kingdom; Department of Imaging Methods, Institute of Measurement Science, Slovak Academy of Sciences, Bratislava, Slovakia.
| | - Marek Chmelík
- High-field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria; Christian Doppler Laboratory for Clinical Molecular MR Imaging, Vienna, Austria; Institute for Clinical Molecular MRI in Musculoskeletal System, Karl Landsteiner Society, Vienna, Austria
| | - Martin Krššák
- High-field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria; Christian Doppler Laboratory for Clinical Molecular MR Imaging, Vienna, Austria; Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
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8
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Layec G, Gifford JR, Trinity JD, Hart CR, Garten RS, Park SY, Le Fur Y, Jeong EK, Richardson RS. Accuracy and precision of quantitative 31P-MRS measurements of human skeletal muscle mitochondrial function. Am J Physiol Endocrinol Metab 2016; 311:E358-66. [PMID: 27302751 PMCID: PMC5005269 DOI: 10.1152/ajpendo.00028.2016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 06/06/2016] [Indexed: 11/22/2022]
Abstract
Although theoretically sound, the accuracy and precision of (31)P-magnetic resonance spectroscopy ((31)P-MRS) approaches to quantitatively estimate mitochondrial capacity are not well documented. Therefore, employing four differing models of respiratory control [linear, kinetic, and multipoint adenosine diphosphate (ADP) and phosphorylation potential], this study sought to determine the accuracy and precision of (31)P-MRS assessments of peak mitochondrial adenosine-triphosphate (ATP) synthesis rate utilizing directly measured peak respiration (State 3) in permeabilized skeletal muscle fibers. In 23 subjects of different fitness levels, (31)P-MRS during a 24-s maximal isometric knee extension and high-resolution respirometry in muscle fibers from the vastus lateralis was performed. Although significantly correlated with State 3 respiration (r = 0.72), both the linear (45 ± 13 mM/min) and phosphorylation potential (47 ± 16 mM/min) models grossly overestimated the calculated in vitro peak ATP synthesis rate (P < 0.05). Of the ADP models, the kinetic model was well correlated with State 3 respiration (r = 0.72, P < 0.05), but moderately overestimated ATP synthesis rate (P < 0.05), while the multipoint model, although being somewhat less well correlated with State 3 respiration (r = 0.55, P < 0.05), most accurately reflected peak ATP synthesis rate. Of note, the PCr recovery time constant (τ), a qualitative index of mitochondrial capacity, exhibited the strongest correlation with State 3 respiration (r = 0.80, P < 0.05). Therefore, this study reveals that each of the (31)P-MRS data analyses, including PCr τ, exhibit precision in terms of mitochondrial capacity. As only the multipoint ADP model did not overstimate the peak skeletal muscle mitochondrial ATP synthesis, the multipoint ADP model is the only quantitative approach to exhibit both accuracy and precision.
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Affiliation(s)
- Gwenael Layec
- Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah; Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah;
| | - Jayson R Gifford
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah; Department of Exercise and Sport Science, University of Utah, Salt Lake City, Utah
| | - Joel D Trinity
- Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah; Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah
| | - Corey R Hart
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah; Department of Exercise and Sport Science, University of Utah, Salt Lake City, Utah
| | - Ryan S Garten
- Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah; Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah
| | - Song Y Park
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah; Department of Exercise and Sport Science, University of Utah, Salt Lake City, Utah
| | - Yann Le Fur
- Aix-Marseille Université, Centre national de la recherche scientifique, Center for Magnetic Resonance in Biology and Medicine, Unité Mixte de Recherche 7339, Marseille, France
| | - Eun-Kee Jeong
- Department of Radiology and Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City, Utah; and
| | - Russell S Richardson
- Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah; Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah; Department of Exercise and Sport Science, University of Utah, Salt Lake City, Utah
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Ydfors M, Hughes MC, Laham R, Schlattner U, Norrbom J, Perry CGR. Modelling in vivo creatine/phosphocreatine in vitro reveals divergent adaptations in human muscle mitochondrial respiratory control by ADP after acute and chronic exercise. J Physiol 2016; 594:3127-40. [PMID: 26631938 DOI: 10.1113/jp271259] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Accepted: 11/19/2015] [Indexed: 01/14/2023] Open
Abstract
KEY POINTS Mitochondrial respiratory sensitivity to ADP is thought to influence muscle fitness and is partly regulated by cytosolic-mitochondrial diffusion of ADP or phosphate shuttling via creatine/phosphocreatine (Cr/PCr) through mitochondrial creatine kinase (mtCK). Previous measurements of respiration in vitro with Cr (saturate mtCK) or without (ADP/ATP diffusion) show mixed responses of ADP sensitivity following acute exercise vs. less sensitivity after chronic exercise. In human muscle, modelling in vivo 'exercising' [Cr:PCr] during in vitro assessments revealed novel responses to exercise that differ from detections with or without Cr (±Cr). Acute exercise increased ADP sensitivity when measured without Cr but had no effect ±Cr or with +Cr:PCr, whereas chronic exercise increased sensitivity ±Cr but lowered sensitivity with +Cr:PCr despite increased markers of mitochondrial oxidative capacity. Controlling in vivo conditions during in vitro respiratory assessments reveals responses to exercise that differ from typical ±Cr comparisons and challenges our understanding of how exercise improves metabolic control in human muscle. ABSTRACT Mitochondrial respiratory control by ADP (Kmapp ) is viewed as a critical regulator of muscle energy homeostasis. However, acute exercise increases, decreases or has no effect on Kmapp in human muscle, whereas chronic exercise surprisingly decreases sensitivity despite greater mitochondrial content. We hypothesized that modelling in vivo mitochondrial creatine kinase (mtCK)-dependent phosphate-shuttling conditions in vitro would reveal increased sensitivity (lower Kmapp ) after acute and chronic exercise. The Kmapp was determined in vitro with 20 mm Cr (+Cr), 0 mm Cr (-Cr) or 'in vivo exercising' 20 mm Cr/2.4 mm PCr (Cr:PCr) on vastus lateralis biopsies sampled from 11 men before, immediately after and 3 h after exercise on the first, fifth and ninth sessions over 3 weeks. Dynamic responses to acute exercise occurred throughout training, whereby the first session did not change Kmapp with in vivo Cr:PCr despite increases in -Cr. The fifth session decreased sensitivity with Cr:PCr or +Cr despite no change in -Cr. Chronic exercise increased sensitivity ±Cr in association with increased electron transport chain content (+33-62% complexes I-V), supporting classic proposals that link increased sensitivity to oxidative capacity. However, in vivo Cr:PCr reveals a perplexing decreased sensitivity, contrasting the increases seen ±Cr. Functional responses occurred without changes in fibre type or proteins regulating mitochondrial-cytosolic energy exchange (mtCK, VDAC and ANT). Despite the dynamic responses seen with ±Cr, modelling in vivo phosphate-shuttling conditions in vitro reveals that ADP sensitivity is unchanged after high-intensity exercise and is decreased after training. These findings challenge our understanding of how exercise regulates skeletal muscle energy homeostasis.
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Affiliation(s)
- Mia Ydfors
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Meghan C Hughes
- School of Kinesiology and Health Science, York University, Toronto, ON, Canada.,Muscle Health Research Centre, York University, Toronto, ON, Canada
| | - Robert Laham
- Muscle Health Research Centre, York University, Toronto, ON, Canada
| | - Uwe Schlattner
- Laboratory of Fundamental and Applied Bioenergetics (LBFA) and SFR Environmental and Systems Biology (BEeSy), University Grenoble Alpes, Grenoble, France
| | - Jessica Norrbom
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Christopher G R Perry
- School of Kinesiology and Health Science, York University, Toronto, ON, Canada.,Muscle Health Research Centre, York University, Toronto, ON, Canada
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10
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Šedivý P, Kipfelsberger MC, Dezortová M, Krššák M, Drobný M, Chmelík M, Rydlo J, Trattnig S, Hájek M, Valkovič L. Dynamic 31P MR spectroscopy of plantar flexion: influence of ergometer design, magnetic field strength (3 and 7 T), and RF-coil design. Med Phys 2015; 42:1678-89. [PMID: 25832057 DOI: 10.1118/1.4914448] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Dynamic phosphorus magnetic resonance spectroscopy ((31)P MRS) during and after acute exercise enables the noninvasive in vivo determination of the mitochondrial capacity of skeletal muscle. Nevertheless, the lack of standardization in experimental setups leads to significant variations in published values of maximal aerobic capacity, even in the population of healthy volunteers. Thus, in this study, we aimed to assess the impact of the ergometer type (pneumatic and mechanical resistance construction), radiofrequency (RF)-coil diameter, and different magnetic field strengths (3 and 7 T) on the metabolic parameters measured by dynamic (31)P MRS during a plantar flexion isotonic exercise protocol within the same group of healthy volunteers. METHODS Dynamic (31)P MRS measurements of the calf muscle in 11 volunteers (mean age, 36 ± 13 yrs; mean BMI, 23.5 ± 2.5 kg/m(2)), on a 3 T MR system with a custom-made mechanical ergometer in the first research laboratory (RL1) and on 3 and 7 T MR systems equipped with a commercial pneumatic ergometer in the second research laboratory (RL2), were performed at three different workloads. RF-coils differed slightly between the sites and MR systems used. The repeatability of the experimental protocol was tested in every setup. The basal concentrations of phosphocreatine (PCr), exercise-induced depletion of PCr (ΔPCr), initial PCr resynthesis rate (VPCr), and mitochondrial capacity (Qmax) were calculated and compared between the research sites and field strengths. RESULTS High repeatability of the measurement protocol was found in every experimental setup. No significant differences at any workload were found in these metabolic parameters assessed at different magnetic field strengths (3 T vs 7 T), using the same ergometer (in RL2) and a similar RF-coil. In the inter-research laboratory comparison at the same field strength (3 T), but with using different ergometers and RF-coils, differences were found in the concentration of PCr measured at rest and in the drop in PCr signal intensity. These differences translated into difference in the value of mitochondrial capacity at a workload of 15% of maximal voluntary contraction (MVC) force (0.45 ± 0.16 mM/s vs 0.31 ± 0.08 mM/s, in the RL1 and RL2, respectively). CONCLUSIONS Metabolic parameters measured during exercise challenge by dynamic (31)P MRS do not depend upon the magnetic field strength used. For multicenter studies with different ergometers, it is important to set the same workload, measurement, and evaluation protocols, especially when the effects of very mild exercise (15% MVC) are to be compared. However, a higher workload (24% MVC) decreases the influence of imperfections and intersite differences for the assessed value of maximal mitochondrial capacity.
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Affiliation(s)
- Petr Šedivý
- MR-Unit, Department of Diagnostic and Interventional Radiology, Institute for Clinical and Experimental Medicine, Prague 140 21, Czech Republic
| | - Monika Christina Kipfelsberger
- High-Field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna A-1090, Austria and Christian Doppler Laboratory for Clinical Molecular MR Imaging, Vienna A-1090, Austria
| | - Monika Dezortová
- MR-Unit, Department of Diagnostic and Interventional Radiology, Institute for Clinical and Experimental Medicine, Prague 140 21, Czech Republic
| | - Martin Krššák
- High-Field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna A-1090, Austria; Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, Vienna A-1090, Austria; and Christian Doppler Laboratory for Clinical Molecular MR Imaging, Vienna A-1090, Austria
| | - Miloslav Drobný
- MR-Unit, Department of Diagnostic and Interventional Radiology, Institute for Clinical and Experimental Medicine, Prague 140 21, Czech Republic
| | - Marek Chmelík
- High-Field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna A-1090, Austria and Christian Doppler Laboratory for Clinical Molecular MR Imaging, Vienna A-1090, Austria
| | - Jan Rydlo
- MR-Unit, Department of Diagnostic and Interventional Radiology, Institute for Clinical and Experimental Medicine, Prague 140 21, Czech Republic
| | - Siegfried Trattnig
- High-Field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna A-1090, Austria and Christian Doppler Laboratory for Clinical Molecular MR Imaging, Vienna A-1090, Austria
| | - Milan Hájek
- MR-Unit, Department of Diagnostic and Interventional Radiology, Institute for Clinical and Experimental Medicine, Prague 140 21, Czech Republic
| | - Ladislav Valkovič
- High-Field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna A-1090, Austria; Department of Imaging Methods, Institute of Measurement Science, Slovak Academy of Sciences, Bratislava 841 04, Slovakia; and Christian Doppler Laboratory for Clinical Molecular MR Imaging, Vienna A-1090, Austria
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11
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Hiepe P, Gussew A, Rzanny R, Kurz E, Anders C, Walther M, Scholle HC, Reichenbach JR. Age-related structural and functional changes of low back muscles. Exp Gerontol 2015; 65:23-34. [PMID: 25735850 DOI: 10.1016/j.exger.2015.02.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Revised: 02/26/2015] [Accepted: 02/27/2015] [Indexed: 01/15/2023]
Abstract
During aging declining maximum force capacity with more or less unchanged fatigability is observed with the underlying mechanisms still not fully understood. Therefore, we compared morphology and function of skeletal muscles between different age groups. Changes in high-energy phosphate turnover (PCr, Pi and pH) and muscle functional MRI (mfMRI) parameters, including proton transverse relaxation time (T2), diffusion (D) and vascular volume fraction (f), were investigated in moderately exercised low back muscles of young and late-middle-aged healthy subjects with (31)P-MR spectroscopy, T2- and diffusion-weighted MRI at 3T. In addition, T1-weighted MRI data were acquired to determine muscle cross-sectional areas (CSA) and to assess fat infiltration into muscle tissue. Except for pH, both age groups showed similar load-induced MR changes and rates of perceived exertion (RPE), which indicates comparable behavior of muscle activation at moderate loads. Changes of mfMRI parameters were significantly associated with RPE in both cohorts. Age-related differences were observed, with lower pH and higher Pi/ATP ratios as well as lower D and f values in the late-middle-aged subjects. These findings are ascribed to age-related changes of fiber type composition, fiber size and vascularity. Interestingly, post exercise f was negatively associated with fat infiltration with the latter being significantly higher in late-middle-aged subjects. CSA of low back muscles remained unchanged, while CSA of inner back muscle as well as mean T2 at rest were associated with maximum force capacity. Overall, applying the proposed MR approach provides evidence of age-related changes in several muscle tissue characteristics and gives new insights into the physiological processes that take place during aging.
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Affiliation(s)
- Patrick Hiepe
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital - Friedrich Schiller University Jena, Germany.
| | - Alexander Gussew
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital - Friedrich Schiller University Jena, Germany
| | - Reinhard Rzanny
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital - Friedrich Schiller University Jena, Germany
| | - Eduard Kurz
- Department for Trauma-, Hand- and Reconstructive Surgery, Division of Motor Research, Pathophysiology and Biomechanics, Jena University Hospital - Friedrich Schiller University Jena, Germany
| | - Christoph Anders
- Department for Trauma-, Hand- and Reconstructive Surgery, Division of Motor Research, Pathophysiology and Biomechanics, Jena University Hospital - Friedrich Schiller University Jena, Germany
| | - Mario Walther
- Institute of Medical Statistics, Computer Sciences and Documentation (IMSID), Jena University Hospital - Friedrich Schiller University Jena, Germany
| | - Hans-Christoph Scholle
- Department for Trauma-, Hand- and Reconstructive Surgery, Division of Motor Research, Pathophysiology and Biomechanics, Jena University Hospital - Friedrich Schiller University Jena, Germany
| | - Jürgen R Reichenbach
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital - Friedrich Schiller University Jena, Germany
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Kemp GJ, Ahmad RE, Nicolay K, Prompers JJ. Quantification of skeletal muscle mitochondrial function by 31P magnetic resonance spectroscopy techniques: a quantitative review. Acta Physiol (Oxf) 2015; 213:107-44. [PMID: 24773619 DOI: 10.1111/apha.12307] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2013] [Revised: 12/30/2013] [Accepted: 04/23/2014] [Indexed: 12/16/2022]
Abstract
Magnetic resonance spectroscopy (MRS) can give information about cellular metabolism in vivo which is difficult to obtain in other ways. In skeletal muscle, non-invasive (31) P MRS measurements of the post-exercise recovery kinetics of pH, [PCr], [Pi] and [ADP] contain valuable information about muscle mitochondrial function and cellular pH homeostasis in vivo, but quantitative interpretation depends on understanding the underlying physiology. Here, by giving examples of the analysis of (31) P MRS recovery data, by some simple computational simulation, and by extensively comparing data from published studies using both (31) P MRS and invasive direct measurements of muscle O2 consumption in a common analytical framework, we consider what can be learnt quantitatively about mitochondrial metabolism in skeletal muscle using MRS-based methodology. We explore some technical and conceptual limitations of current methods, and point out some aspects of the physiology which are still incompletely understood.
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Affiliation(s)
- G. J. Kemp
- Department of Musculoskeletal Biology, and Magnetic Resonance and Image Analysis Research Centre; University of Liverpool; Liverpool UK
| | - R. E. Ahmad
- Department of Musculoskeletal Biology, and Magnetic Resonance and Image Analysis Research Centre; University of Liverpool; Liverpool UK
| | - K. Nicolay
- Biomedical NMR; Department of Biomedical Engineering; Eindhoven University of Technology; Eindhoven the Netherlands
| | - J. J. Prompers
- Biomedical NMR; Department of Biomedical Engineering; Eindhoven University of Technology; Eindhoven the Netherlands
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Larsen RG, Maynard L, Kent JA. High-intensity interval training alters ATP pathway flux during maximal muscle contractions in humans. Acta Physiol (Oxf) 2014; 211:147-60. [PMID: 24612773 DOI: 10.1111/apha.12275] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Revised: 02/18/2014] [Accepted: 03/05/2014] [Indexed: 12/15/2022]
Abstract
AIM High-intensity interval training (HIT) results in potent metabolic adaptations in skeletal muscle; however, little is known about the influence of these adaptations on energetics in vivo. We used magnetic resonance spectroscopy to examine the effects of HIT on ATP synthesis from net PCr breakdown (ATPCK ), oxidative phosphorylation (ATPOX ) and non-oxidative glycolysis (ATPGLY ) in vivo in vastus lateralis during a 24-s maximal voluntary contraction (MVC). METHODS Eight young men performed 6 sessions of repeated, 30-s 'all-out' sprints on a cycle ergometer; measures of muscle energetics were obtained at baseline and after the first and sixth sessions. RESULTS Training increased peak oxygen consumption (35.8 ± 1.4 to 39.3 ± 1.6 mL min(-1) kg(-1) , P = 0.01) and exercise capacity (217.0 ± 11.0 to 230.5 ± 11.7 W, P = 0.04) on the ergometer, with no effects on total ATP production or force-time integral during the MVC. While ATP production by each pathway was unchanged after the first session, 6 sessions increased the relative contribution of ATPOX (from 31 ± 2 to 39 ± 2% of total ATP turnover, P < 0.001) and lowered the relative contribution from both ATPCK (49 ± 2 to 44 ± 1%, P = 0.004) and ATPGLY (20 ± 2 to 17 ± 1%, P = 0.03). CONCLUSION These alterations to muscle ATP production in vivo indicate that brief, maximal contractions are performed with increased support of oxidative ATP synthesis and relatively less contribution from anaerobic ATP production following training. These results extend previous reports of molecular and cellular adaptations to HIT and show that 6 training sessions are sufficient to alter in vivo muscle energetics, which likely contributes to increased exercise capacity after short-term HIT.
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Affiliation(s)
- R. G. Larsen
- Department of Kinesiology; University of Massachusetts; Amherst MA USA
- Department of Health Science and Technology; Aalborg University; Aalborg Denmark
| | - L. Maynard
- Department of Kinesiology; University of Massachusetts; Amherst MA USA
| | - J. A. Kent
- Department of Kinesiology; University of Massachusetts; Amherst MA USA
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Tschiesche K, Rothamel M, Rzanny R, Gussew A, Hiepe P, Reichenbach JR. MR-compatible pedal ergometer for reproducible exercising of the human calf muscle. Med Eng Phys 2014; 36:933-7. [PMID: 24703504 DOI: 10.1016/j.medengphy.2014.02.026] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 02/14/2014] [Accepted: 02/27/2014] [Indexed: 11/29/2022]
Abstract
A pneumatic MR-compatible pedal ergometer was designed to perform dynamic contraction exercises of the human calf muscle in a whole-body 3T MR scanner. The set-up includes sensors for monitoring mechanical parameters, such as pedal angle, cadence as well as applied force and power. Actual parameter values during the exercise were presented to the volunteer as a visual feedback to enable real-time self-adjustment of pedal deflection and cadence to the target reference value. Time-resolved dynamic (31)P-MR spectroscopic measurements of phosphocreatine (PCr), inorganic phosphate (Pi) and pH were performed in a pilot experiment before, during, and after the exercise by a single volunteer. Two different load strengths were applied in these experiments (15% and 25% of the maximum voluntary contraction, MVC). As expected, mechanical and metabolic parameters differed for the two load levels. Small variations of the cadence, power and metabolic changes (time constants of PCr depletion and Pi accumulation) during the experiments demonstrate a highly reproducible mechanical output by the volunteer mediated by the ergometer.
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Affiliation(s)
- Kevin Tschiesche
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology I, Jena University Hospital - Friedrich Schiller University Jena, Germany.
| | - Markus Rothamel
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology I, Jena University Hospital - Friedrich Schiller University Jena, Germany; Medical Engineering and Biotechnology, Jena University of Applied Sciences (EAH Jena), Germany
| | - Reinhard Rzanny
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology I, Jena University Hospital - Friedrich Schiller University Jena, Germany
| | - Alexander Gussew
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology I, Jena University Hospital - Friedrich Schiller University Jena, Germany
| | - Patrick Hiepe
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology I, Jena University Hospital - Friedrich Schiller University Jena, Germany
| | - Jürgen R Reichenbach
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology I, Jena University Hospital - Friedrich Schiller University Jena, Germany
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Layec G, Hart CR, Trinity JD, Richardson RS. Commentary on: an (un)paralleled process? Exp Physiol 2013; 98:1325. [PMID: 23709587 DOI: 10.1113/expphysiol.2013.073775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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