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Pelka EZ, Davis BR, McDaniel J. Sourcebook update: using near-infrared spectroscopy to assess skeletal muscle oxygen uptake. ADVANCES IN PHYSIOLOGY EDUCATION 2024; 48:566-572. [PMID: 38779745 DOI: 10.1152/advan.00047.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Revised: 04/16/2024] [Accepted: 05/12/2024] [Indexed: 05/25/2024]
Abstract
Monitoring the metabolic cost or oxygen consumption associated with rest and exercise is crucial to understanding the impact of disease or physical training on the health of individuals. Traditionally, measuring the skeletal muscle oxygen cost associated with exercise/muscle contractions can be rather expensive or invasive (i.e., muscle biopsies). More recently, specific protocols designed around the use of near-infrared spectroscopy (NIRS) have been shown to provide a quick, noninvasive easy-to-use tool to measure skeletal muscle oxygen consumption ([Formula: see text]). However, the data and results from NIRS devices are often misunderstood. Thus the primary purpose of this sourcebook update is to provide several experimental protocols students can utilize to improve their understanding of NIRS technology, learn how to analyze results from NIRS devices, and better understand how muscle contraction intensity and type (isometric, concentric, or eccentric) influence the oxygen cost of muscle contractions.NEW & NOTEWORTHY Compared to traditional methods, near-infrared spectroscopy (NIRS) provides a relatively cheap and easy-to-use noninvasive technique to measure skeletal muscle oxygen uptake following exercise. This laboratory not only enables students to learn about the basics of NIRS and muscle energetics but also addresses more complex questions regarding skeletal muscle physiology.
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Affiliation(s)
- Edward Z Pelka
- Exercise Science and Exercise Physiology Program, Kent State University, Kent, Ohio, United States
| | - B Ryan Davis
- Exercise Science and Exercise Physiology Program, Kent State University, Kent, Ohio, United States
| | - John McDaniel
- Exercise Science and Exercise Physiology Program, Kent State University, Kent, Ohio, United States
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Lanza IR, Sundberg CW, Kent JA. Reduced oxidative capacity of skeletal muscle IS NOT an inevitable consequence of adult ageing. J Physiol 2024. [PMID: 38970775 DOI: 10.1113/jp285042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 03/04/2024] [Indexed: 07/08/2024] Open
Affiliation(s)
| | | | - Jane A Kent
- University of Massachusetts Amherst, Amherst, USA
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Wahidi R, Zhang Y, Li R, Xu J, Zayed MA, Hastings MK, Zheng J. Quantitative Assessment of Peripheral Oxidative Metabolism With a New Dynamic 1H MRI Technique: A Pilot Study in People With and Without Diabetes Mellitus. J Magn Reson Imaging 2024; 59:2091-2100. [PMID: 37695103 PMCID: PMC10925551 DOI: 10.1002/jmri.28996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 08/19/2023] [Accepted: 08/23/2023] [Indexed: 09/12/2023] Open
Abstract
BACKGROUND Type 2 diabetes mellitus (T2DM) is linked to impaired mitochondrial function. Chemical exchange saturation transfer (CEST) magnetic resonance imaging (MRI) is a gadolinium-contrast-free 1H method to assess mitochondrial function by measuring low-concentration metabolites. A CEST MRI-based technique may serve as a non-invasive proxy for assessing mitochondrial health. HYPOTHESIS A 1H CEST MRI technique may detect significant differences in in vivo skeletal muscle phosphocreatine (SMPCr) kinetics between healthy volunteers and T2DM patients undergoing standardized isometric exercise. STUDY TYPE Cross-sectional study. SUBJECTS Seven subjects without T2DM (T2DM-) and seven age, sex, and BMI-matched subjects with T2DM (T2DM+). FIELD STRENGTH/SEQUENCE Single-shot rapid acquisition with refocusing echoes (RARE) and single-shot gradient-echo sequences, 3 T. ASSESSMENT Subjects underwent a rest-exercise-recovery imaging protocol to dynamically acquire SMPCr maps in calf musculature. Medial gastrocnemius (MG) and soleus SMPCr concentrations were plotted over time, and SMPCr recovery time, τ , was determined. Mitochondrial function index was calculated as the ratio of resting SMPCr to τ . Participants underwent a second exercise protocol for imaging of skeletal muscle blood flow (SMBF), and its association with SMPCr was assessed. STATISTICAL TESTS Unpaired t-tests and Pearson correlation coefficient. A P value <0.05 was considered statistically significant. RESULTS SMPCr concentrations in MG and soleus displayed expected declines during exercise and returns to baseline during recovery. τ was significantly longer in the T2DM+ cohort (MG 83.5 ± 25.8 vs. 54.0 ± 21.1, soleus 90.5 ± 18.9 vs. 51.2 ± 14.5). The mitochondrial function index in the soleus was significantly lower in the T2DM+ cohort (0.33 ± 0.08 vs. 0.66 ± 0.19). SMBF was moderately correlated with the SMPCr in T2DM-; this correlation was not significant in T2DM+ (r = -0.23, P = 0.269). CONCLUSION The CEST MRI method is feasible for quantifying SMPCr in peripheral muscle tissue. T2DM+ individuals had significantly lower oxidative capacities than T2DM- individuals. In T2DM, skeletal muscle metabolism appeared to be decoupled from perfusion. LEVEL OF EVIDENCE 1 TECHNICAL EFFICACY: Stage 1.
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Affiliation(s)
- Ryan Wahidi
- Washington University School of Medicine, Missouri, Saint Louis, USA
| | - Yi Zhang
- Key Laboratory for Biomedical Engineering of Ministry of Education, Department of Biomedical Engineering, College of Biomedical Engineering & Instrument Science, Zhejiang University, Hangzhou, Zhejiang, China
| | - Ran Li
- Washington University School of Medicine, Missouri, Saint Louis, USA
| | - Jiadi Xu
- John Hopkins University, Baltimore, MD, USA
| | - Mohamed A. Zayed
- Washington University School of Medicine, Missouri, Saint Louis, USA
| | - Mary K. Hastings
- Washington University School of Medicine, Missouri, Saint Louis, USA
| | - Jie Zheng
- Washington University School of Medicine, Missouri, Saint Louis, USA
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Yoshiko A, Shiozawa K, Niwa S, Takahashi H, Koike T, Watanabe K, Katayama K, Akima H. Association of skeletal muscle oxidative capacity with muscle function, sarcopenia-related exercise performance, and intramuscular adipose tissue in older adults. GeroScience 2024; 46:2715-2727. [PMID: 38153667 PMCID: PMC10828458 DOI: 10.1007/s11357-023-01043-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 12/10/2023] [Indexed: 12/29/2023] Open
Abstract
Muscle function and exercise performance measures, such as muscle endurance capacity, maximal strength, chair stand score, gait speed, and Timed Up and Go score, are evaluated to diagnose sarcopenia and frailty in older individuals. Furthermore, intramuscular adipose tissue (IntraMAT) content increases with age. Skeletal muscle oxidative capacity determines muscle metabolism and maintains muscle performance. This study aimed to investigate the association of skeletal muscle oxidative capacity with muscle function, exercise performance, and IntraMAT content in older individuals. Thirteen older men and women participated in this study. Skeletal muscle oxidative capacity was assessed by the recovery speed of muscle oxygen saturation after exercise using near-infrared spectroscopy from the medial gastrocnemius. We assessed two muscle functions, peak torque and time to task failure, and four sarcopenia-related exercise performances: handgrip strength, gait speed, 30-s chair stand, and Timed Up and Go. The IntraMAT content was measured using axial magnetic resonance imaging. The results showed a relationship between skeletal muscle oxidative capacity and gait speed but not with muscle functions and other exercise performance measures. Skeletal muscle oxidative capacity was not related to IntraMAT content. Skeletal muscle oxidative capacity, which may be indicative of the capacity of muscle energy production in the mitochondria, is related to locomotive functions but not to other functional parameters or skeletal fat infiltration.
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Affiliation(s)
- Akito Yoshiko
- Faculty of Liberal Arts and Sciences, Chukyo University, Toyota, Japan.
| | - Kana Shiozawa
- Department of Exercise and Sports Physiology, Graduate School of Medicine, Nagoya University, Nagoya, Japan
- Japan Society for the Promotion of Science, Tokyo, Japan
| | - Shiori Niwa
- Department of Nursing, Graduate School of Medicine, Nagoya University, Nagoya, Japan
| | - Hideyuki Takahashi
- Faculty of Health and Sport Sciences, University of Tsukuba, Tsukuba, Japan
| | - Teruhiko Koike
- Research Center of Health, Physical Fitness and Sports, Nagoya University, Nagoya, Japan
- Department of Sports Medicine, Graduate School of Medicine, Nagoya University, Nagoya, Japan
| | - Kohei Watanabe
- School of Health and Sport Sciences, Chukyo University, Toyota, Japan
| | - Keisho Katayama
- Department of Exercise and Sports Physiology, Graduate School of Medicine, Nagoya University, Nagoya, Japan
- Research Center of Health, Physical Fitness and Sports, Nagoya University, Nagoya, Japan
| | - Hiroshi Akima
- Research Center of Health, Physical Fitness and Sports, Nagoya University, Nagoya, Japan
- Graduate School of Education and Human Development, Nagoya University, Nagoya, Japan
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Bartlett MF, Fitzgerald LF, Nagarajan R, Kent JA. Measurements of in vivo skeletal muscle oxidative capacity are lower following sustained isometric compared with dynamic contractions. Appl Physiol Nutr Metab 2024; 49:250-264. [PMID: 37906958 DOI: 10.1139/apnm-2023-0315] [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] [Indexed: 11/02/2023]
Abstract
Human skeletal muscle oxidative capacity can be quantified non-invasively using 31-phosphorus magnetic resonance spectroscopy (31P-MRS) to measure the rate constant of phosphocreatine (PCr) recovery (kPCr) following contractions. In the quadricep muscles, several studies have quantified kPCr following 24-30 s of sustained maximal voluntary isometric contraction (MVIC). This approach has the advantage of simplicity but is potentially problematic because sustained MVICs inhibit perfusion, which may limit muscle oxygen availability or increase the intracellular metabolic perturbation, and thus affect kPCr. Alternatively, dynamic contractions allow reperfusion between contractions, which may avoid limitations in oxygen delivery. To determine whether dynamic contraction protocols elicit greater kPCr than sustained MVIC protocols, we used a cross-sectional design to compare quadriceps kPCr in 22 young and 11 older healthy adults following 24 s of maximal voluntary: (1) sustained MVIC and (2) dynamic (MVDC; 120°·s-1, 1 every 2 s) contractions. Muscle kPCr was ∼20% lower following the MVIC protocol compared with the MVDC protocol (p ≤ 0.001), though this was less evident in older adults (p = 0.073). Changes in skeletal muscle pH (p ≤ 0.001) and PME accumulation (p ≤ 0.001) were greater following the sustained MVIC protocol, and pH (p ≤ 0.001) and PME (p ≤ 0.001) recovery were slower. These results demonstrate that (i) a brief, sustained MVIC yields a lower value for skeletal muscle oxidative capacity than an MVDC protocol of similar duration and (ii) this difference may not be consistent across populations (e.g., young vs. old). Thus, the potential effect of contraction protocol on comparisons of kPCr in different study groups requires careful consideration in the future.
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Affiliation(s)
- Miles F Bartlett
- Department of KinesiologyMuscle Physiology Laboratory, University of Massachusetts Amherst, MA 01003, USA
| | - Liam F Fitzgerald
- Department of KinesiologyMuscle Physiology Laboratory, University of Massachusetts Amherst, MA 01003, USA
| | - Rajakumar Nagarajan
- Human Magnetic Resonance Center, Institute for Applied Life Sciences (IALS), University of Massachusetts Amherst, MA 01003, USA
| | - Jane A Kent
- Department of KinesiologyMuscle Physiology Laboratory, University of Massachusetts Amherst, MA 01003, USA
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Fenzl M, Backens M, Bodea S, Wittemann M, Werler F, Brielmaier J, Wolf RC, Reith W. Impact of cannabis use on brain metabolism using 31P and 1H magnetic resonance spectroscopy. Neuroradiology 2023; 65:1631-1648. [PMID: 37735222 PMCID: PMC10567915 DOI: 10.1007/s00234-023-03220-y] [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: 11/20/2022] [Accepted: 09/06/2023] [Indexed: 09/23/2023]
Abstract
PURPOSE This prospective cross-sectional study investigated the influence of regular cannabis use on brain metabolism in young cannabis users by using combined proton and phosphorus magnetic resonance spectroscopy. METHODS The study was performed in 45 young cannabis users aged 18-30, who had been using cannabis on a regular basis over a period of at least 2 years and in 47 age-matched controls. We acquired 31P MRS data in different brain regions at 3T with a double-resonant 1H/31P head coil, anatomic images, and 1H MRS data with a standard 20-channel 1H head coil. Absolute concentration values of proton metabolites were obtained via calibration from tissue water as an internal reference, whereas a standard solution of 75 mmol/l KH2PO4 was used as an external reference for the calibration of phosphorus signals. RESULTS We found an overall but not statistically significant lower concentration level of several proton and phosphorus metabolites in cannabis users compared to non-users. In particular, energy-related phosphates such as adenosine triphosphate (ATP) and inorganic phosphate (Pi) were reduced in all regions under investigation. Phosphocreatine (PCr) showed lowered values mainly in the left basal ganglia and the left frontal white matter. CONCLUSION The results suggest that the increased risk of functional brain disorders observed in long-term cannabis users could be caused by an impairment of the energy metabolism of the brain, but this needs to be verified in future studies.
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Affiliation(s)
- Maximilian Fenzl
- Institute of Neuroradiology, Saarland University, 66421, Homburg, Germany.
| | - Martin Backens
- Institute of Neuroradiology, Saarland University, 66421, Homburg, Germany.
| | - Silviu Bodea
- Helmholtz Zentrum Munich, German Research Center for Environmental Health Institute of Biological and Medical Imaging, 85748, Munich, Germany
| | - Miriam Wittemann
- Department of Psychiatry and Psychotherapy, Saarland University, 66421, Homburg, Germany
| | - Florian Werler
- Department of General Psychiatry at the Center for Psychosocial Medicine, Heidelberg University, 69115, Heidelberg, Germany
| | - Jule Brielmaier
- Department of Psychiatry and Psychotherapy, Saarland University, 66421, Homburg, Germany
- Department of Obstetrics and Gynecology, RKH Clinic Ludwigsburg, 71640, Ludwigsburg, Germany
| | - Robert Christian Wolf
- Department of General Psychiatry at the Center for Psychosocial Medicine, Heidelberg University, 69115, Heidelberg, Germany
| | - Wolfgang Reith
- Institute of Neuroradiology, Saarland University, 66421, Homburg, Germany
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Zapata Bustos R, Coletta DK, Galons JP, Davidson LB, Langlais PR, Funk JL, Willis WT, Mandarino LJ. Nonequilibrium thermodynamics and mitochondrial protein content predict insulin sensitivity and fuel selection during exercise in human skeletal muscle. Front Physiol 2023; 14:1208186. [PMID: 37485059 PMCID: PMC10361819 DOI: 10.3389/fphys.2023.1208186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Accepted: 06/16/2023] [Indexed: 07/25/2023] Open
Abstract
Introduction: Many investigators have attempted to define the molecular nature of changes responsible for insulin resistance in muscle, but a molecular approach may not consider the overall physiological context of muscle. Because the energetic state of ATP (ΔGATP) could affect the rate of insulin-stimulated, energy-consuming processes, the present study was undertaken to determine whether the thermodynamic state of skeletal muscle can partially explain insulin sensitivity and fuel selection independently of molecular changes. Methods: 31P-MRS was used with glucose clamps, exercise studies, muscle biopsies and proteomics to measure insulin sensitivity, thermodynamic variables, mitochondrial protein content, and aerobic capacity in 16 volunteers. Results: After showing calibrated 31P-MRS measurements conformed to a linear electrical circuit model of muscle nonequilibrium thermodynamics, we used these measurements in multiple stepwise regression against rates of insulin-stimulated glucose disposal and fuel oxidation. Multiple linear regression analyses showed 53% of the variance in insulin sensitivity was explained by 1) VO2max (p = 0.001) and the 2) slope of the relationship of ΔGATP with the rate of oxidative phosphorylation (p = 0.007). This slope represents conductance in the linear model (functional content of mitochondria). Mitochondrial protein content from proteomics was an independent predictor of fractional fat oxidation during mild exercise (R2 = 0.55, p = 0.001). Conclusion: Higher mitochondrial functional content is related to the ability of skeletal muscle to maintain a greater ΔGATP, which may lead to faster rates of insulin-stimulated processes. Mitochondrial protein content per se can explain fractional fat oxidation during mild exercise.
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Affiliation(s)
- Rocio Zapata Bustos
- Division of Endocrinology, Department of Medicine, The University of Arizona, Tucson, AZ, United States
- Center for Disparities in Diabetes, Obesity, and Metabolism, University of Arizona, Tucson, AZ, United States
| | - Dawn K. Coletta
- Division of Endocrinology, Department of Medicine, The University of Arizona, Tucson, AZ, United States
- Center for Disparities in Diabetes, Obesity, and Metabolism, University of Arizona, Tucson, AZ, United States
- Department of Physiology, The University of Arizona, Tucson, AZ, United States
| | - Jean-Philippe Galons
- Department of Medical Imaging, The University of Arizona, Tucson, AZ, United States
| | - Lisa B. Davidson
- Division of Endocrinology, Department of Medicine, The University of Arizona, Tucson, AZ, United States
- Center for Disparities in Diabetes, Obesity, and Metabolism, University of Arizona, Tucson, AZ, United States
| | - Paul R. Langlais
- Division of Endocrinology, Department of Medicine, The University of Arizona, Tucson, AZ, United States
- Center for Disparities in Diabetes, Obesity, and Metabolism, University of Arizona, Tucson, AZ, United States
| | - Janet L. Funk
- Division of Endocrinology, Department of Medicine, The University of Arizona, Tucson, AZ, United States
| | - Wayne T. Willis
- Division of Endocrinology, Department of Medicine, The University of Arizona, Tucson, AZ, United States
- Center for Disparities in Diabetes, Obesity, and Metabolism, University of Arizona, Tucson, AZ, United States
| | - Lawrence J. Mandarino
- Division of Endocrinology, Department of Medicine, The University of Arizona, Tucson, AZ, United States
- Center for Disparities in Diabetes, Obesity, and Metabolism, University of Arizona, Tucson, AZ, United States
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Vogele D, Otto S, Sollmann N, Haggenmüller B, Wolf D, Beer M, Schmidt SA. Sarcopenia - Definition, Radiological Diagnosis, Clinical Significance. ROFO-FORTSCHR RONTG 2023; 195:393-405. [PMID: 36630983 DOI: 10.1055/a-1990-0201] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
BACKGROUND Sarcopenia is an age-related syndrome characterized by a loss of muscle mass and strength. As a result, the independence of the elderly is reduced and the hospitalization rate and mortality increase. The onset of sarcopenia often begins in middle age due to an unbalanced diet or malnutrition in association with a lack of physical activity. This effect is intensified by concomitant diseases such as obesity or metabolic diseases including diabetes mellitus. METHOD With effective preventative diagnostic procedures and specific therapeutic treatment of sarcopenia, the negative effects on the individual can be reduced and the negative impact on health as well as socioeconomic effects can be prevented. Various diagnostic options are available for this purpose. In addition to basic clinical methods such as measuring muscle strength, sarcopenia can also be detected using imaging techniques like dual X-ray absorptiometry (DXA), computed tomography (CT), magnetic resonance imaging (MRI), and sonography. DXA, as a simple and cost-effective method, offers a low-dose option for assessing body composition. With cross-sectional imaging techniques such as CT and MRI, further diagnostic possibilities are available, including MR spectroscopy (MRS) for noninvasive molecular analysis of muscle tissue. CT can also be used in the context of examinations performed for other indications to acquire additional parameters of the skeletal muscles (opportunistic secondary use of CT data), such as abdominal muscle mass (total abdominal muscle area - TAMA) or the psoas as well as the pectoralis muscle index. The importance of sarcopenia is already well studied for patients with various tumor entities and also infections such as SARS-COV2. RESULTS AND CONCLUSION Sarcopenia will become increasingly important, not least due to demographic changes in the population. In this review, the possibilities for the diagnosis of sarcopenia, the clinical significance, and therapeutic options are described. In particular, CT examinations, which are repeatedly performed on tumor patients, can be used for diagnostics. This opportunistic use can be supported by the use of artificial intelligence. KEY POINTS · Sarcopenia is an age-related syndrome with loss of muscle mass and strength.. · Early detection and therapy can prevent negative effects of sarcopenia.. · In addition to DEXA, cross-sectional imaging techniques (CT, MRI) are available for diagnostic purposes.. · The use of artificial intelligence (AI) offers further possibilities in sarcopenia diagnostics.. CITATION FORMAT · Vogele D, Otto S, Sollmann N et al. Sarcopenia - Definition, Radiological Diagnosis, Clinical Significance. Fortschr Röntgenstr 2023; DOI: 10.1055/a-1990-0201.
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Affiliation(s)
- Daniel Vogele
- Department of Diagnostic and Interventional Radiology, University Hospital Ulm, Germany
| | - Stephanie Otto
- Comprehensive Cancer Center (CCCU), University Hospital Ulm, Germany
| | - Nico Sollmann
- Department of Diagnostic and Interventional Radiology, University Hospital Ulm, Germany
| | - Benedikt Haggenmüller
- Department of Diagnostic and Interventional Radiology, University Hospital Ulm, Germany
| | - Daniel Wolf
- Department of Diagnostic and Interventional Radiology, University Hospital Ulm, Germany
| | - Meinrad Beer
- Department of Diagnostic and Interventional Radiology, University Hospital Ulm, Germany
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Voorrips SN, Saucedo-Orozco H, Sánchez-Aguilera PI, De Boer RA, Van der Meer P, Westenbrink BD. Could SGLT2 Inhibitors Improve Exercise Intolerance in Chronic Heart Failure? Int J Mol Sci 2022; 23:ijms23158631. [PMID: 35955784 PMCID: PMC9369142 DOI: 10.3390/ijms23158631] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 07/28/2022] [Accepted: 07/29/2022] [Indexed: 12/04/2022] Open
Abstract
Despite the constant improvement of therapeutical options, heart failure (HF) remains associated with high mortality and morbidity. While new developments in guideline-recommended therapies can prolong survival and postpone HF hospitalizations, impaired exercise capacity remains one of the most debilitating symptoms of HF. Exercise intolerance in HF is multifactorial in origin, as the underlying cardiovascular pathology and reactive changes in skeletal muscle composition and metabolism both contribute. Recently, sodium-related glucose transporter 2 (SGLT2) inhibitors were found to improve cardiovascular outcomes significantly. Whilst much effort has been devoted to untangling the mechanisms responsible for these cardiovascular benefits of SGLT2 inhibitors, little is known about the effect of SGLT2 inhibitors on exercise performance in HF. This review provides an overview of the pathophysiological mechanisms that are responsible for exercise intolerance in HF, elaborates on the potential SGLT2-inhibitor-mediated effects on these phenomena, and provides an up-to-date overview of existing studies on the effect of SGLT2 inhibitors on clinical outcome parameters that are relevant to the assessment of exercise capacity. Finally, current gaps in the evidence and potential future perspectives on the effects of SGLT2 inhibitors on exercise intolerance in chronic HF are discussed.
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Affiliation(s)
- Suzanne N. Voorrips
- Correspondence: (S.N.V.); (B.D.W.); Tel.: +31-50-361-2355 (S.N.V. & B.D.W.); Fax: +31-50-361-4391 (S.N.V. & B.D.W.)
| | | | | | | | | | - B. Daan Westenbrink
- Correspondence: (S.N.V.); (B.D.W.); Tel.: +31-50-361-2355 (S.N.V. & B.D.W.); Fax: +31-50-361-4391 (S.N.V. & B.D.W.)
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Michel CP, Messonnier LA, Giannesini B, Chatel B, Vilmen C, Le Fur Y, Bendahan D. Effects of Hydroxyurea on Skeletal Muscle Energetics and Function in a Mildly Anemic Mouse Model. Front Physiol 2022; 13:915640. [PMID: 35784862 PMCID: PMC9240423 DOI: 10.3389/fphys.2022.915640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 05/16/2022] [Indexed: 11/13/2022] Open
Abstract
Hydroxyurea (HU) is a ribonucleotide reductase inhibitor most commonly used as a therapeutic agent in sickle cell disease (SCD) with the aim of reducing the risk of vaso-occlusion and improving oxygen transport to tissues. Previous studies suggest that HU may be even beneficial in mild anemia. However, the corresponding effects on skeletal muscle energetics and function have never been reported in such a mild anemia model. Seventeen mildly anemic HbAA Townes mice were subjected to a standardized rest-stimulation (transcutaneous stimulation)-protocol while muscle energetics using 31Phosphorus magnetic resonance spectroscopy and muscle force production were assessed and recorded. Eight mice were supplemented with hydroxyurea (HU) for 6 weeks while 9 were not (CON). HU mice displayed a higher specific total force production compared to the CON, with 501.35 ± 54.12 N/mm3 and 437.43 ± 57.10 N/mm3 respectively (+14.6%, p < 0.05). Neither the total rate of energy consumption nor the oxidative metabolic rate were significantly different between groups. The present results illustrated a positive effect of a HU chronic supplementation on skeletal muscle function in mice with mild anemia.
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Affiliation(s)
- Constance P. Michel
- CRMBM, CNRS, Aix Marseille University, Marseille, France
- *Correspondence: Constance P. Michel,
| | - Laurent A. Messonnier
- Laboratoire Interuniversitaire de Biologie de la Motricité, Université Savoie Mont Blanc, Chambéry, France
| | | | - Benjamin Chatel
- CRMBM, CNRS, Aix Marseille University, Marseille, France
- Laboratoire Interuniversitaire de Biologie de la Motricité, Université Savoie Mont Blanc, Chambéry, France
| | | | - Yann Le Fur
- CRMBM, CNRS, Aix Marseille University, Marseille, France
| | - David Bendahan
- CRMBM, CNRS, Aix Marseille University, Marseille, France
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11
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Kunz HE, Port JD, Kaufman KR, Jatoi A, Hart CR, Gries KJ, Lanza IR, Kumar R. Skeletal muscle mitochondrial dysfunction and muscle and whole body functional deficits in cancer patients with weight loss. J Appl Physiol (1985) 2022; 132:388-401. [PMID: 34941442 PMCID: PMC8791841 DOI: 10.1152/japplphysiol.00746.2021] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Reductions in skeletal muscle mass and function are often reported in patients with cancer-associated weight loss and are associated with reduced quality of life, impaired treatment tolerance, and increased mortality. Although cellular changes, including altered mitochondrial function, have been reported in animals, such changes have been incompletely characterized in humans with cancer. Whole body and skeletal muscle physical function, skeletal muscle mitochondrial function, and whole body protein turnover were assessed in eight patients with cancer-associated weight loss (10.1 ± 4.2% body weight over 6-12 mo) and 19 age-, sex-, and body mass index (BMI)-matched healthy controls to characterize skeletal muscle changes at the whole body, muscle, and cellular level. Potential pathways involved in cancer-induced alterations in metabolism and mitochondrial function were explored by interrogating skeletal muscle and plasma metabolomes. Despite similar lean mass compared with control participants, patients with cancer exhibited reduced habitual physical activity (57% fewer daily steps), cardiorespiratory fitness [22% lower V̇o2peak (mL/kg/min)] and leg strength (35% lower isokinetic knee extensor strength), and greater leg neuromuscular fatigue (36% greater decline in knee extensor torque). Concomitant with these functional declines, patients with cancer had lower mitochondrial oxidative capacity [25% lower State 3 O2 flux (pmol/s/mg tissue)] and ATP production [23% lower State 3 ATP production (pmol/s/mg tissue)] and alterations in phospholipid metabolite profiles indicative of mitochondrial abnormalities. Whole body protein turnover was unchanged. These findings demonstrate mitochondrial abnormalities concomitant with whole body and skeletal muscle functional derangements associated with human cancer, supporting future work studying the role of mitochondria in the muscle deficits associated with cancer.NEW & NOTEWORTHY To our knowledge, this is the first study to suggest that skeletal muscle mitochondrial deficits are associated with cancer-associated weight loss in humans. Mitochondrial deficits were concurrent with reductions in whole body and skeletal muscle functional capacity. Whether mitochondrial deficits are causal or secondary to cancer-associated weight loss and functional deficits remains to be determined, but this study supports further exploration of mitochondria as a driver of cancer-associated losses in muscle mass and function.
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Affiliation(s)
- Hawley E. Kunz
- 1Endocrine Research Unit, Division of Endocrinology, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota
| | - John D. Port
- 2Division of Neuroradiology, Department of Radiology, Mayo Clinic, Rochester, Minnesota
| | - Kenton R. Kaufman
- 3Motion Analysis Laboratory, Department of Orthopedic Surgery, Mayo Clinic, Rochester, Minnesota
| | - Aminah Jatoi
- 4Department of Oncology, Mayo Clinic, Rochester, Minnesota
| | - Corey R. Hart
- 1Endocrine Research Unit, Division of Endocrinology, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota
| | - Kevin J. Gries
- 1Endocrine Research Unit, Division of Endocrinology, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota
| | - Ian R. Lanza
- 1Endocrine Research Unit, Division of Endocrinology, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota
| | - Rajiv Kumar
- 5Nephrology and Hypertension Research Unit, Division of Nephrology and Hypertension, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota,6Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota
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12
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Arakawa M, Kitahara T, Inadomi D, Iikubo M, Hyakutake H, Yuasa K, Takahashi I. Molecular imaging in masseter muscle observed by muscle function magnetic resonance imaging and 31 P-magnetic resonance spectroscopy in patients with a jaw deformity. Clin Exp Dent Res 2021; 8:231-238. [PMID: 34623750 PMCID: PMC8874048 DOI: 10.1002/cre2.494] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 09/03/2021] [Indexed: 11/12/2022] Open
Abstract
Background Skeletal mandibular protrusion would influence to the muscle fatigue of the masticatory muscles. Establishing a diagnostic procedures combining physiological and biochemical information is necessary for quantitative evaluation of masticatory muscle fatigue. Objective The transverse relaxation time (T2 time) of muscle functional magnetic resonance imaging (mfMRI), and 31P‐magnetic resonance spectroscopy (MRS) were used to investigate the reliability as parameters for measuring the masseter muscle in patients with skeletal mandibular prognathism. Method The subjects were 19 patients diagnosed as skeletal mandibular protrusions and 19 healthy subjects as a control group. Transverse relaxation time (T2 value) determined by mfMRI along with creatine phosphate (PCr) and inorganic phosphorus (Pi) determined by 31P‐MRS before, during, and after clenching were used for molecular imaging of muscle fatigue. Results The average T2 value of the patient group was significantly higher than that of the healthy control group at rest. Furthermore, the average T2 value transiently increased in both groups during experimental clenching. The PCr and Pi showed a tendency toward a transient decrease and increases, respectively. The pH in the masseter muscle showed a transient decrease in both groups prior to and following experimental clenching. The pH in the masseter muscle of the patient group was significantly lower than that in the healthy control group at rest and recovery. Conclusion We showed mfMRI and 31P‐MRS are useful for evaluating masseter fatigue during clenching, and the masseter muscle in the prognathic patients showed more severe fatigue than the healthy controls.
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Affiliation(s)
- Masahiro Arakawa
- Section of Orthodontics and Dentofacial Orthopedics, Graduate School of Dentistry, Kyushu University, Fukuoka, Japan
| | - Toru Kitahara
- Section of Orthodontics and Dentofacial Orthopedics, Faculty of Dental Science, Kyushu University, Fukuoka, Japan
| | - Daisuke Inadomi
- Radiology Center, Fukuoka Dental College Hospital, Fukuoka, Japan
| | - Masahiro Iikubo
- Department of Oral Diagnosis, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Hiroto Hyakutake
- Graduate School of Information Sciences, Hiroshima City University, Hiroshima, Japan
| | - Kenji Yuasa
- Section of Image Diagnosis, Department of Diagnostics and General Care, Fukuoka Dental College, Fukuoka, Japan
| | - Ichiro Takahashi
- Section of Orthodontics and Dentofacial Orthopedics, Faculty of Dental Science, Kyushu University, Fukuoka, Japan
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13
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Chatel B, Ducreux S, Harhous Z, Bendridi N, Varlet I, Ogier AC, Bernard M, Gondin J, Rieusset J, Westerblad H, Bendahan D, Gineste C. Impaired aerobic capacity and premature fatigue preceding muscle weakness in the skeletal muscle Tfam-knockout mouse model. Dis Model Mech 2021; 14:272176. [PMID: 34378772 PMCID: PMC8461820 DOI: 10.1242/dmm.048981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Accepted: 07/30/2021] [Indexed: 11/20/2022] Open
Abstract
Mitochondrial diseases are genetic disorders that lead to impaired mitochondrial function, resulting in exercise intolerance and muscle weakness. In patients, muscle fatigue due to defects in mitochondrial oxidative capacities commonly precedes muscle weakness. In mice, deletion of the fast-twitch skeletal muscle-specific Tfam gene (Tfam KO) leads to a deficit in respiratory chain activity, severe muscle weakness and early death. Here, we performed a time-course study of mitochondrial and muscular dysfunctions in 11- and 14-week-old Tfam KO mice, i.e. before and when mice are about to enter the terminal stage, respectively. Although force in the unfatigued state was reduced in Tfam KO mice compared to control littermates (wild type) only at 14 weeks, during repeated submaximal contractions fatigue was faster at both ages. During fatiguing stimulation, total phosphocreatine breakdown was larger in Tfam KO muscle than in wild-type muscle at both ages, whereas phosphocreatine consumption was faster only at 14 weeks. In conclusion, the Tfam KO mouse model represents a reliable model of lethal mitochondrial myopathy in which impaired mitochondrial energy production and premature fatigue occur before muscle weakness and early death. Summary: A time-course study of mitochondrial and muscular dysfunctions in a mouse model of mitochondrial myopathy reveals that decreased resistance to fatigue together with decreased oxidative capacities arise ahead of muscle weakness.
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Affiliation(s)
- Benjamin Chatel
- Aix-Marseille Université, CRMBM UMR CNRS 7339, 13385 Marseille, France.,CellMade, 73370 Le-Bourget-du-Lac, France
| | - Sylvie Ducreux
- CarMeN Laboratory, UMR INSERM U1060/INRA U1397, Université Claude Bernard Lyon1, F-69310 Pierre-Bénite et F-69500 Bron, France
| | - Zeina Harhous
- CarMeN Laboratory, UMR INSERM U1060/INRA U1397, Université Claude Bernard Lyon1, F-69310 Pierre-Bénite et F-69500 Bron, France
| | - Nadia Bendridi
- CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, 69600 Oullins, France
| | - Isabelle Varlet
- Aix-Marseille Université, CRMBM UMR CNRS 7339, 13385 Marseille, France
| | - Augustin C Ogier
- Aix-Marseille Université, Université de Toulon, CNRS, LIS, 13397 Marseille, France
| | - Monique Bernard
- Aix-Marseille Université, CRMBM UMR CNRS 7339, 13385 Marseille, France
| | - Julien Gondin
- Institut NeuroMyoGène, UMR CNRS 5310 - INSERM U1217, Université Claude Bernard Lyon 1, F-69008 Lyon, France
| | - Jennifer Rieusset
- CarMeN Laboratory, UMR INSERM U1060/INRA U1397, Université Claude Bernard Lyon1, F-69310 Pierre-Bénite et F-69500 Bron, France
| | - Håkan Westerblad
- Department of Physiology and Pharmacology, Karolinska Institutet, 17177 Stockholm, Sweden
| | - David Bendahan
- Aix-Marseille Université, CRMBM UMR CNRS 7339, 13385 Marseille, France
| | - Charlotte Gineste
- Aix-Marseille Université, CRMBM UMR CNRS 7339, 13385 Marseille, France
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14
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DePauw EM, Rouhani M, Flanagan AM, Ng AV. Forearm muscle mitochondrial capacity and resting oxygen uptake: Relationship to symptomatic fatigue in persons with multiple sclerosis. Mult Scler J Exp Transl Clin 2021; 7:20552173211028875. [PMID: 34262786 PMCID: PMC8246512 DOI: 10.1177/20552173211028875] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 06/10/2021] [Indexed: 11/30/2022] Open
Abstract
Background Mitochondrial dysfunction has been implicated in the pathogenesis of multiple sclerosis (MS). Whether mitochondrial alterations are a function of ambulatory dysfunction or are of a non-ambulatory systemic nature is unclear. Objective To compare oxidative capacity, and rest muscle oxygen consumption (mVO2) in the upper limb of persons with multiple sclerosis (PwMS) to a control group (CON), whereby an upper limb would be comparatively independent of ambulation or deconditioning. Methods Near infra-red spectroscopy was used to measure oxidative capacity of the wrist flexors in PwMS (n = 16) and CON (n = 13). Oxidative capacity was indicated by the time constant (TC) of mVO2 recovery following brief wrist flexion contractions. Measurements included well-being, depression, symptomatic fatigue, disability, handgrip strength, cognition, and functional endurance. Analysis was by T-tests and Pearson correlations with p ≤ 0.05. Data are mean (SD). Results TC of mVO2 recovery was slower in PwMS (MS = 47(14) sec, CON = 36(11) sec; p = 0.03). No significant correlations were found between oxidative capacity and any other measures. Rest mVO2 was not different between groups, but correlated with symptomatic fatigue (r = 0.694, p = 0.003) and strength (0.585, p = 0.017) in PwMS. Conclusion Oxidative capacity was lower in the wrist flexors of PwMS, possibly indicating a systemic component of the disease. Within PwMS, rest mVO2 was associated with symptomatic fatigue.
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Affiliation(s)
- Elizabeth M DePauw
- Program in Exercise Science, Department of Physical Therapy, Marquette University, Milwaukee, WI, USA
| | - Mitra Rouhani
- Exercise and Rehabilitation Science program, Department of Physical Therapy, Marquette University, Milwaukee, WI, USA
| | - Aidan M Flanagan
- Program in Exercise Science, Department of Physical Therapy, Marquette University, Milwaukee, WI, USA
| | - Alexander V Ng
- Program in Exercise Science, Department of Physical Therapy, Marquette University, Milwaukee, WI, USA
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15
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Liu F, Wanigatunga AA, Zampino M, Knuth ND, Simonsick EM, Schrack JA, Ferrucci L. Association of Mitochondrial Function, Substrate Utilization, and Anaerobic Metabolism With Age-Related Perceived Fatigability. J Gerontol A Biol Sci Med Sci 2021; 76:426-433. [PMID: 32803242 DOI: 10.1093/gerona/glaa201] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Indexed: 11/13/2022] Open
Abstract
Previous work has shown that poorer mitochondrial function is associated with age-related perceived fatigability. However, whether glucose oxidation and anaerobic metabolism are intermediate factors underlying this association remains unclear. We examined the total cross-sectional association between mitochondrial function and perceived fatigability in 554 adults aged 22-99 years. Mitochondrial function was assessed by skeletal muscle oxidative capacity (kPCr) using 31P magnetic resonance spectroscopy. Perceived fatigability was measured by rating of perceived exertion after a 5-minute (0.67 m/s) treadmill walk. The intermediate role of glucose oxidation (measured by the rate of change of respiratory exchange ratio [RER change rate] during the 5-minute treadmill walk) and anaerobic metabolism (measured by ventilatory threshold [VeT] during a maximal treadmill test) was evaluated by examining their cross-sectional associations with kPCr and perceived exertion. For each 0.01/s lower kPCr, perceived fatigability was 0.47 points higher (p = .002). A 0.01/s lower kPCr was also associated with 8.3 L/min lower VeT (p < .001). Lower VeT was associated with higher fatigability at lower levels of kPCr but not at higher kPCr levels (β for interaction = 0.017, p = .002). kPCr and RER change rate were not significantly associated (p = .341), but a 0.01/min higher RER change rate was associated with 0.12-point higher fatigability (p = .001). Poorer mitochondrial function potentially contributes to higher perceived fatigability through higher glucose oxidation and higher anaerobic metabolism. Future studies to further explore the longitudinal mechanisms between these metabolic changes and fatigability are warranted.
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Affiliation(s)
- Fangyu Liu
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.,Center on Aging and Health, Johns Hopkins University, Baltimore, Maryland
| | - Amal A Wanigatunga
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.,Center on Aging and Health, Johns Hopkins University, Baltimore, Maryland
| | - Marta Zampino
- National Institute on Aging, National Institutes of Health, Baltimore, Maryland
| | | | - Eleanor M Simonsick
- National Institute on Aging, National Institutes of Health, Baltimore, Maryland
| | - Jennifer A Schrack
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.,Center on Aging and Health, Johns Hopkins University, Baltimore, Maryland
| | - Luigi Ferrucci
- National Institute on Aging, National Institutes of Health, Baltimore, Maryland
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16
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van Diemen MPJ, Hart EP, Hameeteman PW, Coppen EM, Winder JY, den Heijer J, Moerland M, Kan H, van der Grond J, Webb A, Roos RAC, Groeneveld GJ. Brain Bio-Energetic State Does Not Correlate to Muscle Mitochondrial Function in Huntington's Disease. J Huntingtons Dis 2020; 9:335-344. [PMID: 33325391 DOI: 10.3233/jhd-200413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Huntington's disease (HD) is a neurodegenerative disease with cognitive, motor and psychiatric symptoms. A toxic accumulation of misfolded mutant huntingtin protein (Htt) induces mitochondrial dysfunction, leading to a bioenergetic insufficiency in neuronal and muscle cells. Improving mitochondrial function has been proposed as an opportunity to treat HD, but it is not known how mitochondrial function in different tissues relates. OBJECTIVE We explored associations between central and peripheral mitochondrial function in a group of mild to moderate staged HD patients. METHODS We used phosphorous magnetic resonance spectroscopy (31P-MRS) to measure mitochondrial function in vivo in the calf muscle (peripheral) and the bio-energetic state in the visual cortex (central). Mitochondrial function was also assessed ex vivo in circulating peripheral blood mononuclear cells (PBMCs). Clinical function was determined by the Unified Huntington's Disease Rating Scale (UHDRS) total motor score. Pearson correlation coefficients were computed to assess the correlation between the different variables. RESULTS We included 23 manifest HD patients for analysis. There was no significant correlation between central bio-energetics and peripheral mitochondrial function. Central mitochondrial function at rest correlated significantly to the UHDRS total motor score (R = -0.45 and -0.48), which increased in a subgroup with the largest number of CAG repeats. DISCUSSION We did not observe a correlation between peripheral and central mitochondrial function. Central, but not peripheral, mitochondrial function correlated to clinical function. Muscle mitochondrial function is a promising biomarker to evaluate disease-modifying compounds that improve mitochondrial function, but Huntington researchers should use central mitochondrial function to demonstrate proof-of-pharmacology of disease-modifying compounds.
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Affiliation(s)
| | - Ellen P Hart
- Centre for Human Drug Research, Leiden, The Netherlands
| | | | - Emma M Coppen
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands
| | - Jessica Y Winder
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands
| | | | | | - Hermien Kan
- Gorter Centre for High-field MRI, Leiden University Medical Center, Leiden, The Netherlands
| | - Jeroen van der Grond
- Radiology Research Center, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Andrew Webb
- Gorter Centre for High-field MRI, Leiden University Medical Center, Leiden, The Netherlands
| | - Raymund A C Roos
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands
| | - Geert Jan Groeneveld
- Centre for Human Drug Research, Leiden, The Netherlands.,Department of Anesthesiology, Leiden University Medical Center, Leiden, The Netherlands
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17
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Bartlett MF, Fitzgerald LF, Nagarajan R, Kent JA. Validity and accuracy of calculating oxidative ATP synthesis in vivo during high-intensity skeletal muscle contractions. NMR IN BIOMEDICINE 2020; 33:e4381. [PMID: 32803787 DOI: 10.1002/nbm.4381] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 06/27/2020] [Accepted: 07/02/2020] [Indexed: 06/11/2023]
Abstract
Several methods have been developed for using 31 P-MRS to calculate rates of oxidative ATP synthesis (ATPOX ) during muscular contractions based on assumptions that (1) the ATP cost of force generation (ATPCOST ) remains constant or (2) Michaelis-Menten coupling between cytosolic ADP and ATPOX does not change. However, growing evidence suggests that one, or both, of these assumptions are invalid during high-intensity fatigue protocols. Consequently, there is a need to examine the validity and accuracy of traditional ATPOX calculation methods under these conditions. To address this gap, we measured phosphate concentrations and pH in the vastus lateralis muscle of nine young adults during four rest-contraction-recovery trials lasting 24, 60, 120, and 240 s. The initial velocity of phosphocreatine resynthesis (ViPCr ) following each trial served as the criterion measure of ATPOX because this method makes no assumptions of constant ATPCOST or Michaelis-Menten coupling between changes in cytosolic ADP and ATPOX . Subsequently, we calculated ATPOX throughout the 240 s trial using several traditional calculation methods and compared estimations of ATPOX from each method with time-matched measurements of ViPCr . Method 1, which assumes that ATPCOST does not change, was able to model changes in ViPCr over time, but showed poor accuracy for predicting ViPCr across a wide range of ATPOX values. In contrast, Michaelis-Menten methods, which assume that the relationship between changes in cytosolic ADP and ATPOX remains constant, were invalid because they could not model the decline in ViPCr . However, adjusting these Michaelis-Menten methods for observed changes in maximal ATPOX capacity (i.e., Vmax ) permitted modeling of the decline in ViPCr and markedly improved accuracy. The results of these comprehensive analyses demonstrate that valid, accurate measurements of ATPOX can be obtained during high-intensity contractions by adjusting Michaelis-Menten ATPOX calculations for changes in Vmax observed from baseline to post-fatigue.
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Affiliation(s)
- Miles F Bartlett
- Muscle Physiology Laboratory, Department of Kinesiology, University of Massachusetts Amherst, Amherst, Massachusetts, USA
| | - Liam F Fitzgerald
- Muscle Physiology Laboratory, Department of Kinesiology, University of Massachusetts Amherst, Amherst, Massachusetts, USA
| | - Rajakumar Nagarajan
- Human Magnetic Resonance Center, Institute for Applied Life Sciences (IALS), University of Massachusetts Amherst, Amherst, Massachusetts, USA
| | - Jane A Kent
- Muscle Physiology Laboratory, Department of Kinesiology, University of Massachusetts Amherst, Amherst, Massachusetts, USA
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18
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Beever AT, Tripp TR, Zhang J, MacInnis MJ. NIRS-derived skeletal muscle oxidative capacity is correlated with aerobic fitness and independent of sex. J Appl Physiol (1985) 2020; 129:558-568. [PMID: 32702279 PMCID: PMC7517427 DOI: 10.1152/japplphysiol.00017.2020] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 06/26/2020] [Accepted: 07/19/2020] [Indexed: 01/03/2023] Open
Abstract
Near-infrared spectroscopy (NIRS) provides a simple and reliable measure of skeletal muscle oxidative capacity; however, its relationship to aerobic fitness and sex are unclear. We hypothesized that NIRS-derived oxidative capacity in the vastus lateralis (VL) and medial gastrocnemius (MG) would be correlated with indices of aerobic fitness and independent of sex. Twenty-six participants (13 males, 13 females) performed ramp- and step-incremental tests to volitional exhaustion on separate days to establish maximal oxygen uptake (V̇o2max), peak power output (PPO), lactate threshold (LT), gas exchange threshold (GET), respiratory compensation point (RCP), and maximal fat oxidation (MFO). Data were normalized to lean body mass to account for sex-based differences in body composition. Exercise tests were preceded by duplicate measurements of NIRS-derived oxidative capacity on the VL and MG muscles (i.e., repeated arterial occlusions following a brief set of muscle contractions). Skeletal muscle oxidative capacity for the VL (means ± SD: 21.9 ± 4.6 s) and MG (22.5 ± 6.1 s) were similar but unrelated (r2 = 0.03, P = 0.39). Skeletal muscle oxidative capacity for the VL, but not the MG (P > 0.05 for all variables), was significantly correlated with V̇o2max (r2 = 0.24; P = 0.01), PPO (r2 = 0.23; P = 0.01), LT (r2 = 0.23; P = 0.01), GET (r2 = 0.23; P = 0.01), and RCP (r2 = 0.27; P = 0.006). MFO was not correlated with VL or MG skeletal muscle oxidative capacity (P > 0.05). Females (54.9 ± 4.5 mL·kg LBM-1·min-1) and males (56.0 ± 6.2 mL·kg LBM-1·min-1), matched for V̇o2max (P = 0.62), had similar NIRS-derived oxidative capacities for VL (20.7 ± 4.4 vs. 23.2 ± 4.6 s; P = 0.18) and MG (24.4 ± 6.8 vs. 20.5 ± 4.8 s; P = 0.10). Overall, NIRS-derived skeletal muscle oxidative capacity in VL is indicative of aerobic fitness and independent of sex in humans.NEW & NOTEWORTHY Near-infrared spectroscopy (NIRS) can be used to measure skeletal muscle oxidative capacity. Here, we demonstrated that NIRS-derived skeletal muscle oxidative capacity of the vastus lateralis was independent of sex, reliable across and within days, and correlated with maximal and submaximal indices of aerobic fitness, including maximal oxygen uptake, lactate threshold, and respiratory compensation point. These findings highlight the utility of NIRS for investigating skeletal muscle oxidative capacity in females and males.
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Affiliation(s)
- Austin T Beever
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Thomas R Tripp
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Jenny Zhang
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Martin J MacInnis
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
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19
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Kumar AA, Kelly DP, Chirinos JA. Mitochondrial Dysfunction in Heart Failure With Preserved Ejection Fraction. Circulation 2019; 139:1435-1450. [PMID: 30856000 DOI: 10.1161/circulationaha.118.036259] [Citation(s) in RCA: 136] [Impact Index Per Article: 27.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Heart failure with preserved ejection fraction (HFpEF) is a complex syndrome with an increasingly recognized heterogeneity in pathophysiology. Exercise intolerance is the hallmark of HFpEF and appears to be caused by both cardiac and peripheral abnormalities in the arterial tree and skeletal muscle. Mitochondrial abnormalities can significantly contribute to impaired oxygen utilization and the resulting exercise intolerance in HFpEF. We review key aspects of the complex biology of this organelle, the clinical relevance of mitochondrial function, the methods that are currently available to assess mitochondrial function in humans, and the evidence supporting a role for mitochondrial dysfunction in the pathophysiology of HFpEF. We also discuss the role of mitochondrial function as a therapeutic target, some key considerations for the design of early-phase clinical trials using agents that specifically target mitochondrial function to improve symptoms in patients with HFpEF, and ongoing trials with mitochondrial agents in HFpEF.
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Affiliation(s)
- Anupam A Kumar
- From the University of Pennsylvania Perelman School of Medicine, Philadelphia (A.K., D.P.K., J.C.)
| | - Daniel P Kelly
- From the University of Pennsylvania Perelman School of Medicine, Philadelphia (A.K., D.P.K., J.C.)
| | - Julio A Chirinos
- From the University of Pennsylvania Perelman School of Medicine, Philadelphia (A.K., D.P.K., J.C.).,the Hospital of the University of Pennsylvania, Philadelphia (J.C.)
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20
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Chung S, Nelson MD, Hamaoka T, Jacobs RA, Pearson J, Subudhi AW, Jenkins NT, Bartlett MF, Fitzgerald LF, Miehm JD, Kent JA, Lucero AA, Rowlands DS, Stoner L, McCully KK, Call J, Rodriguez-Miguelez P, Harris RA, Porcelli S, Rasica L, Marzorati M, Quaresima V, Ryan TE, Vernillo G, Millet GP, Malatesta D, Millet GY, Zuo L, Chuang CC. Commentaries on Viewpoint: Principles, insights, and potential pitfalls of the noninvasive determination of muscle oxidative capacity by near-infrared spectroscopy. J Appl Physiol (1985) 2019; 124:249-255. [PMID: 29364790 DOI: 10.1152/japplphysiol.00857.2017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | - Lee Stoner
- Massey University,University of North Carolina at Chapel Hill
| | | | | | | | | | | | - Letizia Rasica
- National Research Council, Italy,University of Milan, Italy
| | | | | | | | | | | | | | | | - Li Zuo
- The Ohio State University College of Medicine
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21
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Bock C, Wermter FC, Schalkhausser B, Blicher ME, Pörtner HO, Lannig G, Sejr MK. In vivo 31P-MRS of muscle bioenergetics in marine invertebrates: Future ocean limits scallops' performance. Magn Reson Imaging 2019; 61:239-246. [DOI: 10.1016/j.mri.2019.06.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 05/15/2019] [Accepted: 06/02/2019] [Indexed: 10/26/2022]
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22
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Krikken E, van der Kemp WJ, Khlebnikov V, van Dalen T, Los M, van Laarhoven HW, Luijten PR, van den Bosch MA, Klomp DW, Wijnen JP. Contradiction between amide-CEST signal and pH in breast cancer explained with metabolic MRI. NMR IN BIOMEDICINE 2019; 32:e4110. [PMID: 31136039 PMCID: PMC6772111 DOI: 10.1002/nbm.4110] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 04/08/2019] [Accepted: 04/09/2019] [Indexed: 06/09/2023]
Abstract
PURPOSE Metabolic MRI is a noninvasive technique that can give new insights into understanding cancer metabolism and finding biomarkers to evaluate or monitor treatment plans. Using this technique, a previous study has shown an increase in pH during neoadjuvant chemotherapy (NAC) treatment, while recent observation in a different study showed a reduced amide proton transfer (APT) signal during NAC treatment (negative relation). These findings are counterintuitive, given the known intrinsic positive relation of APT signal to pH. METHODS In this study we combined APT MRI and 31 P-MRSI measurements to unravel the relation between the APT signal and pH in breast cancer. Twenty-two breast cancer patients were scanned with a 7 T MRI before and after the first cycle of NAC treatment. pH was determined by the chemical shift of inorganic phosphate (Pi). RESULTS While APT signals have a positive relation to pH and amide content, we observed a direct negative linear correlation between APT signals and pH in breast tumors in vivo. CONCLUSIONS As differentiation of cancer stages was confirmed by observation of a linear correlation between cell proliferation marker PE/Pi (phosphoethanolamine over inorganic phosphate) and pH in the tumor, our data demonstrates that the concentration of mobile proteins likely supersedes the contribution of the exchange rate to the APT signal.
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Affiliation(s)
- Erwin Krikken
- Department of RadiologyUniversity Medical Center UtrechtUtrechtThe Netherlands
| | | | - Vitaliy Khlebnikov
- Department of RadiologyUniversity Medical Center UtrechtUtrechtThe Netherlands
| | | | - Maartje Los
- Department of Medical OncologySt. Antonius ZiekenhuisNieuwegein/UtrechtThe Netherlands
| | - Hanneke W.M. van Laarhoven
- Department of Medical Oncology, Academic Medical Centre AmsterdamCancer Center AmsterdamAmsterdamThe Netherlands
| | - Peter R. Luijten
- Department of RadiologyUniversity Medical Center UtrechtUtrechtThe Netherlands
| | | | - Dennis W.J. Klomp
- Department of RadiologyUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Jannie P. Wijnen
- Department of RadiologyUniversity Medical Center UtrechtUtrechtThe Netherlands
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23
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Bakermans AJ, Wessel CH, Zheng KH, Groot PFC, Stroes ESG, Nederveen AJ. Dynamic magnetic resonance measurements of calf muscle oxygenation and energy metabolism in peripheral artery disease. J Magn Reson Imaging 2019; 51:98-107. [PMID: 31218803 PMCID: PMC6916546 DOI: 10.1002/jmri.26841] [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: 04/09/2019] [Accepted: 06/04/2019] [Indexed: 12/15/2022] Open
Abstract
Background Clinical assessments of peripheral artery disease (PAD) severity are insensitive to pathophysiological changes in muscle tissue oxygenation and energy metabolism distal to the affected artery. Purpose To quantify the blood oxygenation level‐dependent (BOLD) response and phosphocreatine (PCr) recovery kinetics on a clinical MR system during a single exercise‐recovery session in PAD patients. Study Type Case–control study. Subjects Fifteen Fontaine stage II patients, and 18 healthy control subjects Field Strength/Sequence Interleaved dynamic multiecho gradient‐echo 1H T2* mapping and adiabatic pulse‐acquire 31P‐MR spectroscopy at 3T. Assessment Blood pressure in the arms and ankles were measured to determine the ankle‐brachial index (ABI). Subjects performed a plantar flexion exercise‐recovery protocol. The gastrocnemius and soleus muscle BOLD responses were characterized using the T2* maps. High‐energy phosphate metabolite concentrations were quantified by fitting the series of 31P‐MR spectra. The PCr recovery time constant (τPCr) was derived as a measure of in vivo mitochondrial oxidative capacity. Statistical Tests Comparisons between groups were performed using two‐sided Mann–Whitney U‐tests. Relations between variables were assessed by Pearson's r correlation coefficients. Results The amplitude of the functional hyperemic BOLD response in the gastrocnemius muscle was higher in PAD patients compared with healthy subjects (–3.8 ± 1.4% vs. –1.4 ± 0.3%; P < 0.001), and correlated with the ABI (r = 0.79; P < 0.001). PCr recovery was slower in PAD patients (τPCr = 52.0 ± 13.5 vs. 30.3 ± 9.7 sec; P < 0.0001), and correlated with the ABI (r = –0.64; P < 0.001). Moreover, τPCr correlated with the hyperemic BOLD response in the gastrocnemius muscle (r = –0.66; P < 0.01). Data Conclusion MR readouts of calf muscle tissue oxygenation and high‐energy phosphate metabolism were acquired essentially simultaneously during a single exercise‐recovery session. A pronounced hypoxia‐triggered vasodilation in PAD is associated with a reduced mitochondrial oxidative capacity. Level of Evidence: 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2020;51:98–107.
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Affiliation(s)
- Adrianus J Bakermans
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Chang Ho Wessel
- Department of Vascular Medicine, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Kang H Zheng
- Department of Vascular Medicine, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Paul F C Groot
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Erik S G Stroes
- Department of Vascular Medicine, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Aart J Nederveen
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
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Charles-Edwards G, Amaral N, Sleigh A, Ayis S, Catibog N, McDonagh T, Monaghan M, Amin-Youssef G, Kemp GJ, Shah AM, Okonko DO. Effect of Iron Isomaltoside on Skeletal Muscle Energetics in Patients With Chronic Heart Failure and Iron Deficiency. Circulation 2019; 139:2386-2398. [DOI: 10.1161/circulationaha.118.038516] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
| | - Nelson Amaral
- King’s College London British Heart Foundation Centre of Excellence, School of Cardiovascular Medicine and Sciences, James Black Centre, UK (N.A., N.C., T.M., M.M., A.M.S., D.O.O.)
- Department of Cardiology, King’s College Hospital NHS Foundation Trust, London, UK (N.A., N.C., T.M., M.M., G.A.-Y., A.M.S., D.O.O.)
| | - Alison Sleigh
- Wolfson Brain Imaging Centre, University of Cambridge School of Clinical Medicine, UK (A.S.)
- Wellcome Trust-MRC Institute of Metabolic Science, Cambridge, UK (A.S.)
- NIHR/Wellcome Trust Clinical Research Facility, Cambridge University Hospitals NHS Foundation Trust, UK (A.S.)
| | - Salma Ayis
- School of Population Health and Environmental Sciences, Kings College London, UK (S.A.)
| | - Norman Catibog
- King’s College London British Heart Foundation Centre of Excellence, School of Cardiovascular Medicine and Sciences, James Black Centre, UK (N.A., N.C., T.M., M.M., A.M.S., D.O.O.)
- Department of Cardiology, King’s College Hospital NHS Foundation Trust, London, UK (N.A., N.C., T.M., M.M., G.A.-Y., A.M.S., D.O.O.)
| | - Theresa McDonagh
- King’s College London British Heart Foundation Centre of Excellence, School of Cardiovascular Medicine and Sciences, James Black Centre, UK (N.A., N.C., T.M., M.M., A.M.S., D.O.O.)
- Department of Cardiology, King’s College Hospital NHS Foundation Trust, London, UK (N.A., N.C., T.M., M.M., G.A.-Y., A.M.S., D.O.O.)
| | - Mark Monaghan
- King’s College London British Heart Foundation Centre of Excellence, School of Cardiovascular Medicine and Sciences, James Black Centre, UK (N.A., N.C., T.M., M.M., A.M.S., D.O.O.)
- Department of Cardiology, King’s College Hospital NHS Foundation Trust, London, UK (N.A., N.C., T.M., M.M., G.A.-Y., A.M.S., D.O.O.)
| | - George Amin-Youssef
- Department of Cardiology, King’s College Hospital NHS Foundation Trust, London, UK (N.A., N.C., T.M., M.M., G.A.-Y., A.M.S., D.O.O.)
| | - Graham J. Kemp
- Department of Musculoskeletal Biology, University of Liverpool and MRC-Arthritis Research UK Centre for Integrated research into Musculoskeletal Ageing (CIMA), Liverpool (G.J.K.)
| | - Ajay M. Shah
- King’s College London British Heart Foundation Centre of Excellence, School of Cardiovascular Medicine and Sciences, James Black Centre, UK (N.A., N.C., T.M., M.M., A.M.S., D.O.O.)
- Department of Cardiology, King’s College Hospital NHS Foundation Trust, London, UK (N.A., N.C., T.M., M.M., G.A.-Y., A.M.S., D.O.O.)
| | - Darlington O. Okonko
- King’s College London British Heart Foundation Centre of Excellence, School of Cardiovascular Medicine and Sciences, James Black Centre, UK (N.A., N.C., T.M., M.M., A.M.S., D.O.O.)
- Department of Cardiology, King’s College Hospital NHS Foundation Trust, London, UK (N.A., N.C., T.M., M.M., G.A.-Y., A.M.S., D.O.O.)
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Sundberg CW, Prost RW, Fitts RH, Hunter SK. Bioenergetic basis for the increased fatigability with ageing. J Physiol 2019; 597:4943-4957. [PMID: 31018011 DOI: 10.1113/jp277803] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 04/18/2019] [Indexed: 12/25/2022] Open
Abstract
KEY POINTS The mechanisms for the age-related increase in fatigability during dynamic exercise remain elusive. We tested whether age-related impairments in muscle oxidative capacity would result in a greater accumulation of fatigue causing metabolites, inorganic phosphate (Pi ), hydrogen (H+ ) and diprotonated phosphate (H2 PO4 - ), in the muscle of old compared to young adults during a dynamic knee extension exercise. The age-related increase in fatigability (reduction in mechanical power) of the knee extensors was closely associated with a greater accumulation of metabolites within the working muscle but could not be explained by age-related differences in muscle oxidative capacity. These data suggest that the increased fatigability in old adults during dynamic exercise is primarily determined by age-related impairments in skeletal muscle bioenergetics that result in a greater accumulation of metabolites. ABSTRACT The present study aimed to determine whether the increased fatigability in old adults during dynamic exercise is associated with age-related differences in skeletal muscle bioenergetics. Phosphorus nuclear magnetic resonance spectroscopy was used to quantify concentrations of high-energy phosphates and pH in the knee extensors of seven young (22.7 ± 1.2 years; six women) and eight old adults (76.4 ± 6.0 years; seven women). Muscle oxidative capacity was measured from the phosphocreatine (PCr) recovery kinetics following a 24 s maximal voluntary isometric contraction. The fatiguing exercise consisted of 120 maximal velocity contractions (one contraction per 2 s) against a load equivalent to 20% of the maximal voluntary isometric contraction. The PCr recovery kinetics did not differ between young and old adults (0.023 ± 0.007 s-1 vs. 0.019 ± 0.004 s-1 , respectively). Fatigability (reductions in mechanical power) of the knee extensors was ∼1.8-fold greater with age and was accompanied by a greater decrease in pH (young = 6.73 ± 0.09, old = 6.61 ± 0.04) and increases in concentrations of inorganic phosphate, [Pi ], (young = 22.7 ± 4.8 mm, old = 32.3 ± 3.6 mm) and diprotonated phosphate, [H2 PO4 - ], (young = 11.7 ± 3.6 mm, old = 18.6 ± 2.1 mm) at the end of the exercise in old compared to young adults. The age-related increase in power loss during the fatiguing exercise was strongly associated with intracellular pH (r = -0.837), [Pi ] (r = 0.917) and [H2 PO4 - ] (r = 0.930) at the end of the exercise. These data suggest that the age-related increase in fatigability during dynamic exercise has a bioenergetic basis and is explained by an increased accumulation of metabolites within the muscle.
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Affiliation(s)
- Christopher W Sundberg
- Department of Biological Sciences, Marquette University, Milwaukee, WI, USA.,Department of Physical Therapy, Marquette University, Milwaukee, WI, USA
| | - Robert W Prost
- Department of Radiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Robert H Fitts
- Department of Biological Sciences, Marquette University, Milwaukee, WI, USA
| | - Sandra K Hunter
- Department of Physical Therapy, Marquette University, Milwaukee, WI, USA
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26
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Warnez‐Soulie J, Macia M, Lac S, Pecchi E, Bernard M, Bendahan D, Bartoli M, Carrier A, Giannesini B. Tumor protein 53-induced nuclear protein 1 deficiency alters mouse gastrocnemius muscle function and bioenergetics in vivo. Physiol Rep 2019; 7:e14055. [PMID: 31124296 PMCID: PMC6533175 DOI: 10.14814/phy2.14055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 03/14/2019] [Indexed: 12/06/2022] Open
Abstract
Tumor protein 53-induced nuclear protein 1 (TP53INP1) deficiency leads to oxidative stress-associated obesity and insulin resistance. Although skeletal muscle has a predominant role in the development of metabolic syndrome, the bioenergetics and functional consequences of TP53INP1 deficiency upon this tissue remain undocumented. To clarify this issue, gastrocnemius muscle mechanical performance, energy metabolism, and anatomy were investigated in TP53INP1-deficient and wild-type mice using a multidisciplinary approach implementing noninvasive multimodal-NMR techniques. TP53INP1 deficiency increased body adiposity but did not affect cytosolic oxidative stress, lipid content, and mitochondrial pool and capacity in myocyte. During a fatiguing bout of exercise, the in vivo oxidative ATP synthesis capacity was dramatically reduced in TP53INP1-deficient mice despite ADP level (the main in vivo stimulator of mitochondrial respiration) did not differ between both genotypes. Moreover, TP53INP1 deficiency did not alter fatigue resistance but paradoxically increased the contractile force, whereas there were no differences for muscle fiber-type distribution and calcium homeostasis between both genotypes. In addition, muscle proton efflux was decreased in TP53INP1-deficient mice, thereby indicating a reduced blood supply. In conclusion, TP53INP1 plays a role in muscle function and bioenergetics through oxidative capacity impairment possibly as the consequence of abnormal mitochondrial respiration regulation and/or defective blood supply.
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Affiliation(s)
| | | | - Sophie Lac
- Aix Marseille Univ, CNRS, INSERM, Institut Paoli‐Calmettes, CRCMMarseilleFrance
| | | | | | | | | | - Alice Carrier
- Aix Marseille Univ, CNRS, INSERM, Institut Paoli‐Calmettes, CRCMMarseilleFrance
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27
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Semba RD, Moaddel R, Zhang P, Ramsden CE, Ferrucci L. Tetra-linoleoyl cardiolipin depletion plays a major role in the pathogenesis of sarcopenia. Med Hypotheses 2019; 127:142-149. [PMID: 31088638 DOI: 10.1016/j.mehy.2019.04.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 04/16/2019] [Indexed: 12/25/2022]
Abstract
Sarcopenia, the progressive loss of muscle mass, strength, and physical performance that occurs during aging, is highly prevalent among the elderly. Sarcopenia increases the risk of falls, disability, and death. The biological basis for sarcopenia is not well understood. There are no specific preventive or therapeutic strategies for sarcopenia except exercise. The elucidation of biological pathways and identification of therapeutic targets for treating or preventing sarcopenia remain a high priority in aging research. Mitochondria play a critical role in skeletal muscle by providing energy in the form of ATP, regulation of signaling, calcium homeostasis, autophagy, and other functions. Cardiolipin, a unique dimeric phospholipid specific to mitochondria and an essential component of mitochondrial membranes, is involved in mitochondrial protein transport, maintaining structural organization of mitochondrial membranes, cellular signaling, regulating enzymes involved in β-oxidation of fatty acids, and facilitating normal electron transport chain (ETC) function and generation of ATP. The fatty acid species composition of cardiolipin is critical to mitochondrial bioenergetics, as cardiolipin affects membrane biophysical properties, binds and stabilizes ETC protein complexes, and shapes the curvature of the mitochondrial cristae. Tetra-linoleoyl cardiolipin (18:2)4 comprises ∼80% of cardiolipin in mitochondria in normal human skeletal and cardiac muscle and is optimal for effective ETC function and ATP generation. Aging is associated with a decrease in cardiolipin content, decrease in tetra-linoleoyl cardiolipin (18:2)4 and replacement of linoleic acid (18:2) with other fatty acids in cardiolipin composition, decline of ETC function, and increased generation of reactive oxygen species in muscle. Together, these findings from the literature prompt the hypothesis that depletion of the cardiolipin (18:2)4 species may be at the root of mitochondrial dysfunction with aging, in turn leading to sarcopenia. Corroboration of the tetra-linoleoyl cardiolipin depletion hypothesis suggests new leads for the prevention and treatment of sarcopenia by enhancing the biosynthesis, accretion, and integrity of tetra-linoleoyl cardiolipin.
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Affiliation(s)
- Richard D Semba
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, United States.
| | - Ruin Moaddel
- National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
| | - Pingbo Zhang
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Christopher E Ramsden
- National Institute on Aging, National Institutes of Health, Baltimore, MD, United States; National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, United States
| | - Luigi Ferrucci
- National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
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28
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Layec G, Trinity JD, Hart CR, Le Fur Y, Zhao J, Reese V, Jeong EK, Richardson RS. Impaired Muscle Efficiency but Preserved Peripheral Hemodynamics and Mitochondrial Function With Advancing Age: Evidence From Exercise in the Young, Old, and Oldest-Old. J Gerontol A Biol Sci Med Sci 2018; 73:1303-1312. [PMID: 29584857 PMCID: PMC6132121 DOI: 10.1093/gerona/gly050] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Accepted: 03/20/2018] [Indexed: 12/17/2022] Open
Abstract
Muscle weakness in the elderly has been linked to recurrent falls and morbidity; therefore, elucidating the mechanisms contributing to the loss of muscle function and mobility with advancing age is critical. To this aim, we comprehensively examined skeletal muscle metabolic function and hemodynamics in 11 young (23 ± 2 years), 11 old (68 ± 2 years), and 10 oldest-old (84 ± 2 years) physical activity-matched participants. Specifically, oxidative stress markers, mitochondrial function, and the ATP cost of contraction as well as peripheral hemodynamics were assessed during dynamic plantar flexion exercise at 40 per cent of maximal work rate (WRmax). Both the PCr recovery time constant and the peak rate of mitochondrial ATP synthesis were not significantly different between groups. In contrast, the ATP cost of dynamic contractions (young: 1.5 ± 1.0, old: 3.4 ± 2.1, oldest-old: 6.1 ± 3.6 mM min-1 W-1) and systemic markers of oxidative stress were signficantly increased with age, with the ATP cost of contraction being negatively correlated with WRmax (r = .59, p < .05). End-of-exercise blood flow per Watt rose significantly with increasing age (young: 37 ± 20, old: 82 ± 68, oldest-old: 154 ± 93 mL min-1 W-1). These findings suggest that the progressive deterioration of muscle contractile efficiency with advancing age may play an important role in the decline in skeletal muscle functional capacity in the elderly.
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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 VA Medical Center, Salt Lake City, Utah
- Department of Nutrition and Integrative Physiology, 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 VA Medical Center, Salt Lake City, Utah
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Corey R Hart
- Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah
- Geriatric Research, Education, and Clinical Center, George E. Whalen VA 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, CNRS, CRMBM, UMR, Marseille, France
| | - Jia Zhao
- Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah
| | - Van Reese
- Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah
| | - Eun-Kee Jeong
- Department of Radiology and Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City, Utah
| | - 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 VA Medical Center, Salt Lake City, Utah
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
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Mitochondrial function is impaired in the skeletal muscle of pre-frail elderly. Sci Rep 2018; 8:8548. [PMID: 29867098 PMCID: PMC5986740 DOI: 10.1038/s41598-018-26944-x] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 05/23/2018] [Indexed: 01/15/2023] Open
Abstract
Aging is accompanied by a gradual decline in both muscle mass and strength over time, which can eventually lead to pathologies, such as frailty and sarcopenia. While these two conditions are well characterized, further investigation of the early biological signs present in pre-frail elderly is still needed to help identify strategies for preventative therapeutic intervention. The goal of the present clinical study was to evaluate the level of mitochondrial (dys)function in a well-defined population of pre-frail elderly (>60 years of age). Pre-frail elderly were compared with an age-matched population of active elderly. Muscle mitochondrial function was assessed in vivo using phosphorus magnetic resonance spectroscopy (31P-MRS) and a comprehensive set of biological biomarkers were measured ex vivo in vastus lateralis muscle biopsies. In pre-frail subjects, phosphocreatine recovery was impaired and mitochondrial respiratory complex protein and activity levels were significantly lower when compared with active elderly. Analysis of microarray data showed that mitochondrial genes were also significantly down-regulated in muscle of pre-frail compared to active elderly. These results show that mitochondrial impairment is a hallmark of pre-frailty development and the onset of decline in muscle function in the elderly.
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30
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Jones AM, Vanhatalo A. The 'Critical Power' Concept: Applications to Sports Performance with a Focus on Intermittent High-Intensity Exercise. Sports Med 2018; 47:65-78. [PMID: 28332113 PMCID: PMC5371646 DOI: 10.1007/s40279-017-0688-0] [Citation(s) in RCA: 132] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The curvilinear relationship between power output and the time for which it can be sustained is a fundamental and well-known feature of high-intensity exercise performance. This relationship 'levels off' at a 'critical power' (CP) that separates power outputs that can be sustained with stable values of, for example, muscle phosphocreatine, blood lactate, and pulmonary oxygen uptake ([Formula: see text]), from power outputs where these variables change continuously with time until their respective minimum and maximum values are reached and exercise intolerance occurs. The amount of work that can be done during exercise above CP (the so-called W') is constant but may be utilized at different rates depending on the proximity of the exercise power output to CP. Traditionally, this two-parameter CP model has been employed to provide insights into physiological responses, fatigue mechanisms, and performance capacity during continuous constant power output exercise in discrete exercise intensity domains. However, many team sports (e.g., basketball, football, hockey, rugby) involve frequent changes in exercise intensity and, even in endurance sports (e.g., cycling, running), intensity may vary considerably with environmental/course conditions and pacing strategy. In recent years, the appeal of the CP concept has been broadened through its application to intermittent high-intensity exercise. With the assumptions that W' is utilized during work intervals above CP and reconstituted during recovery intervals below CP, it can be shown that performance during intermittent exercise is related to four factors: the intensity and duration of the work intervals and the intensity and duration of the recovery intervals. However, while the utilization of W' may be assumed to be linear, studies indicate that the reconstitution of W' may be curvilinear with kinetics that are highly variable between individuals. This has led to the development of a new CP model for intermittent exercise in which the balance of W' remaining ([Formula: see text]) may be calculated with greater accuracy. Field trials of athletes performing stochastic exercise indicate that this [Formula: see text] model can accurately predict the time at which W' tends to zero and exhaustion is imminent. The [Formula: see text] model potentially has important applications in the real-time monitoring of athlete fatigue progression in endurance and team sports, which may inform tactics and influence pacing strategy.
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Affiliation(s)
- Andrew M Jones
- Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Heavitree Road, Exeter, EX12LU, UK.
| | - Anni Vanhatalo
- Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Heavitree Road, Exeter, EX12LU, UK
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Zhang S, Chen M, Gao L, Liu Y. Investigating Muscle Function After Stroke Rehabilitation with 31P-MRS: A Preliminary Study. Med Sci Monit 2018; 24:2841-2848. [PMID: 29730667 PMCID: PMC5958628 DOI: 10.12659/msm.907372] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Accepted: 11/16/2017] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND New evidence reveals significant metabolic changes in skeletal muscle after stroke. However, it is unknown if 31P magnetic resonance spectroscopy (31P-MRS) can evaluate these metabolic changes. Our objective here was to investigate: (a) if muscle energy metabolism changes in the affected side; (b) if muscle energy metabolism changes after rehabilitation; and (c) if energy metabolism measured by 31P-MRS can reflect changes in the Modified Modified Ashworth Scale (MMAS) and Fugl-Meyer assessment-lower extremity (FMA-LE) scores after rehabilitation. MATERIAL AND METHODS We enrolled 13 patients with stroke symptoms and hemiplegia. Lower-limb motor status on the affected side was evaluated by FMA-LE and MMAS. The 31P-MRS measures included phosphocreatine (PCr), inorganic phosphate (Pi), PCr/Pi, and pH. We statistically compared these measures in the affected and unaffected lower leg muscles before rehabilitation and after rehabilitation on the affected side. Spearman correlational analyses was performed to determine correlations between change in energy metabolism and change in FMA-LE score and MMAS score after rehabilitation. RESULTS PCr and PCr/Pi were significantly lower in the affected muscle compared to the unaffected muscle; however, there were no significant differences in Pi or pH. After rehabilitation, PCr, Pi, PCr/Pi, and pH did not significantly change. However, FMA-LE and MMAS score improved significantly after rehabilitation. Changes in energy metabolism measured by 31P-MRS had no correlation with FMA-LE change after rehabilitation. However, changes in PCr and PCr/Pi were correlated with change in MMAS score after rehabilitation. CONCLUSIONS 31P-MRS can evaluate changes in muscle energy metabolism in patients with stroke. PCr measured by 31P-MRS can reflect changes in MMAS after rehabilitation.
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Affiliation(s)
- Shuai Zhang
- Department of Radiology, Beijing Hospital, National Center of Gerontology, Beijing, P.R. China
- Graduate School, Peking Union Medical College, Beijing, P.R. China
| | - Min Chen
- Department of Radiology, Beijing Hospital, National Center of Gerontology, Beijing, P.R. China
- Graduate School, Peking Union Medical College, Beijing, P.R. China
| | - Lei Gao
- Department of Radiology, Beijing Hospital, National Center of Gerontology, Beijing, P.R. China
- Department of Rehabilitation, Beijing Hospital, National Center of Gerontology, Beijing, P.R. China
| | - Ying Liu
- Department of Radiology, Beijing Hospital, National Center of Gerontology, Beijing, P.R. China
- Graduate School, Peking University Health Science Center, Peking University, Beijing, P.R. China
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Sedivy P, Dezortova M, Drobny M, Vlasakova Z, Herynek V, Hajek M. Differences in muscle metabolism in patients with type I diabetes - influence of gender and nephropathy studied by (31)P MR spectroscopy. Physiol Res 2018. [PMID: 29527910 DOI: 10.33549/physiolres.933745] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Type I diabetes mellitus (DM1) is a complex disease with adverse effects on organs and tissues despite compensation by insulin treatment. The goal of our study was to study how kidney diseases change (31)P MR parameters of muscle metabolism in DM1 patients with respect to gender. 51 DM1 patients (19 m/14 f without and 13 m/5 f with nephropathy) and 26 (14 m/12 f) healthy volunteers were examined using (31)P magnetic resonance spectroscopy at 3T tomograph at rest, and during and after a calf muscle exercise. The exercise consisted of a six-minute plantar flexion using a pedal ergometer followed by a six-minute recovery. It is reflected by reduced relative beta-ATP and increased Pi and phosphodiester signals to phosphocreatine (PCr) at rest and prolongation of the PCr recovery time after the exercise. Measurement on healthy volunteers indicated differences between males and females in pH at the rest and after the exercise only. These differences between patients groups were not significant. We have proven that nephropathy affects the metabolism in diabetic patients and our results confirm significant difference between patients with and without nephropathy. Gender differences in pH were observed only between male and female healthy volunteers.
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Affiliation(s)
- P Sedivy
- MR-Unit, Department of Diagnostic and Interventional Radiology, Institute for Clinical and Experimental Medicine, Prague 4, Czech Republic.
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Abstract
Changes in mitochondrial capacity and quality play a critical role in skeletal and cardiac muscle dysfunction. In vivo measurements of mitochondrial capacity provide a clear link between physical activity and mitochondrial function in aging and heart failure, although the cause and effect relationship remains unclear. Age-related decline in mitochondrial quality leads to mitochondrial defects that affect redox, calcium, and energy-sensitive signaling by altering the cellular environment that can result in skeletal muscle dysfunction independent of reduced mitochondrial capacity. This reduced mitochondrial quality with age is also likely to sensitize skeletal muscle mitochondria to elevated angiotensin or beta-adrenergic signaling associated with heart failure. This synergy between aging and heart failure could further disrupt cell energy and redox homeostasis and contribute to exercise intolerance in this patient population. Therefore, the interaction between aging and heart failure, particularly with respect to mitochondrial dysfunction, should be a consideration when developing strategies to improve quality of life in heart failure patients. Given the central role of the mitochondria in skeletal and cardiac muscle dysfunction, mitochondrial quality may provide a common link for targeted interventions in these populations.
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Affiliation(s)
- Sophia Z Liu
- Department of Radiology, University of Washington, Box 358050, Seattle, WA, 98109, USA
| | - David J Marcinek
- Department of Radiology, University of Washington, Box 358050, Seattle, WA, 98109, USA. .,Department of Pathology, University of Washington, Seattle, WA, 98109, USA. .,Department of Bioengineering, University of Washington, Seattle, WA, 98109, USA.
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Liu Y, Gu Y, Yu X. Assessing tissue metabolism by phosphorous-31 magnetic resonance spectroscopy and imaging: a methodology review. Quant Imaging Med Surg 2017; 7:707-726. [PMID: 29312876 PMCID: PMC5756783 DOI: 10.21037/qims.2017.11.03] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 11/11/2017] [Indexed: 01/11/2023]
Abstract
Many human diseases are caused by an imbalance between energy production and demand. Magnetic resonance spectroscopy (MRS) and magnetic resonance imaging (MRI) provide the unique opportunity for in vivo assessment of several fundamental events in tissue metabolism without the use of ionizing radiation. Of particular interest, phosphate metabolites that are involved in ATP generation and utilization can be quantified noninvasively by phosphorous-31 (31P) MRS/MRI. Furthermore, 31P magnetization transfer (MT) techniques allow in vivo measurement of metabolic fluxes via creatine kinase (CK) and ATP synthase. However, a major impediment for the clinical applications of 31P-MRS/MRI is the prohibitively long acquisition time and/or the low spatial resolution that are necessary to achieve adequate signal-to-noise ratio. In this review, current 31P-MRS/MRI techniques used in basic science and clinical research are presented. Recent advances in the development of fast 31P-MRS/MRI methods are also discussed.
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Affiliation(s)
- Yuchi Liu
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Yuning Gu
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Xin Yu
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
- Department of Radiology, Case Western Reserve University, Cleveland, OH, USA
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH, USA
- Case Center for Imaging Research, Case Western Reserve University, Cleveland, OH, USA
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van Diemen MP, Berends CL, Akram N, Wezel J, Teeuwisse WM, Mik BG, Kan HE, Webb A, Beenakker JWM, Groeneveld GJ. Validation of a pharmacological model for mitochondrial dysfunction in healthy subjects using simvastatin: A randomized placebo-controlled proof-of-pharmacology study. Eur J Pharmacol 2017; 815:290-297. [DOI: 10.1016/j.ejphar.2017.09.031] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 09/16/2017] [Accepted: 09/20/2017] [Indexed: 10/18/2022]
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Weiss K, Schär M, Panjrath GS, Zhang Y, Sharma K, Bottomley PA, Golozar A, Steinberg A, Gerstenblith G, Russell SD, Weiss RG. Fatigability, Exercise Intolerance, and Abnormal Skeletal Muscle Energetics in Heart Failure. Circ Heart Fail 2017; 10:CIRCHEARTFAILURE.117.004129. [PMID: 28705910 DOI: 10.1161/circheartfailure.117.004129] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 06/16/2017] [Indexed: 11/16/2022]
Abstract
BACKGROUND Among central and peripheral factors contributing to exercise intolerance (EI) in heart failure (HF), the extent to which skeletal muscle (SM) energy metabolic abnormalities occur and contribute to EI and increased fatigability in HF patients with reduced or preserved ejection fraction (HFrEF and HFpEF, respectively) are not known. An energetic plantar flexion exercise fatigability test and magnetic resonance spectroscopy were used to probe the mechanistic in vivo relationships among SM high-energy phosphate concentrations, mitochondrial function, and EI in HFrEF and HFpEF patients and in healthy controls. METHODS AND RESULTS Resting SM high-energy phosphate concentrations and ATP flux rates were normal in HFrEF and HFpEF patients. Fatigue occurred at similar SM energetic levels in all subjects, consistent with a common SM energetic limit. Importantly, HFrEF New York Heart Association class II-III patients with EI and high fatigability exhibited significantly faster rates of exercise-induced high-energy phosphate decline than did HFrEF patients with low fatigability (New York Heart Association class I), despite similar left ventricular ejection fractions. HFpEF patients exhibited severe EI, the most rapid rates of high-energy phosphate depletion during exercise, and impaired maximal oxidative capacity. CONCLUSIONS Symptomatic fatigue during plantar flexion exercise occurs at a common energetic limit in all subjects. HFrEF and HFpEF patients with EI and increased fatigability manifest early, rapid exercise-induced declines in SM high-energy phosphates and reduced oxidative capacity compared with healthy and low-fatigability HF patients, suggesting that SM metabolism is a potentially important target for future HF treatment strategies.
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Affiliation(s)
- Kilian Weiss
- From the Division of Cardiology, Department of Medicine (K.W., G.S.P., K.S., A.S., G.G., S.D.R., R.G.W.) and Division of Magnetic Resonance Research, Department of Radiology (K.W., M.S., P.A.B.), Johns Hopkins University School of Medicine, Baltimore, MD; Philips Healthcare Germany, Hamburg, Germany (K.W.); Heart Failure and Circulatory Support Program, George Washington University School of Medicine, DC (G.S.P.); and Johns Hopkins School of Public Health, Baltimore, MD (A.G.)
| | - Michael Schär
- From the Division of Cardiology, Department of Medicine (K.W., G.S.P., K.S., A.S., G.G., S.D.R., R.G.W.) and Division of Magnetic Resonance Research, Department of Radiology (K.W., M.S., P.A.B.), Johns Hopkins University School of Medicine, Baltimore, MD; Philips Healthcare Germany, Hamburg, Germany (K.W.); Heart Failure and Circulatory Support Program, George Washington University School of Medicine, DC (G.S.P.); and Johns Hopkins School of Public Health, Baltimore, MD (A.G.)
| | - Gurusher S Panjrath
- From the Division of Cardiology, Department of Medicine (K.W., G.S.P., K.S., A.S., G.G., S.D.R., R.G.W.) and Division of Magnetic Resonance Research, Department of Radiology (K.W., M.S., P.A.B.), Johns Hopkins University School of Medicine, Baltimore, MD; Philips Healthcare Germany, Hamburg, Germany (K.W.); Heart Failure and Circulatory Support Program, George Washington University School of Medicine, DC (G.S.P.); and Johns Hopkins School of Public Health, Baltimore, MD (A.G.)
| | - Yi Zhang
- From the Division of Cardiology, Department of Medicine (K.W., G.S.P., K.S., A.S., G.G., S.D.R., R.G.W.) and Division of Magnetic Resonance Research, Department of Radiology (K.W., M.S., P.A.B.), Johns Hopkins University School of Medicine, Baltimore, MD; Philips Healthcare Germany, Hamburg, Germany (K.W.); Heart Failure and Circulatory Support Program, George Washington University School of Medicine, DC (G.S.P.); and Johns Hopkins School of Public Health, Baltimore, MD (A.G.)
| | - Kavita Sharma
- From the Division of Cardiology, Department of Medicine (K.W., G.S.P., K.S., A.S., G.G., S.D.R., R.G.W.) and Division of Magnetic Resonance Research, Department of Radiology (K.W., M.S., P.A.B.), Johns Hopkins University School of Medicine, Baltimore, MD; Philips Healthcare Germany, Hamburg, Germany (K.W.); Heart Failure and Circulatory Support Program, George Washington University School of Medicine, DC (G.S.P.); and Johns Hopkins School of Public Health, Baltimore, MD (A.G.)
| | - Paul A Bottomley
- From the Division of Cardiology, Department of Medicine (K.W., G.S.P., K.S., A.S., G.G., S.D.R., R.G.W.) and Division of Magnetic Resonance Research, Department of Radiology (K.W., M.S., P.A.B.), Johns Hopkins University School of Medicine, Baltimore, MD; Philips Healthcare Germany, Hamburg, Germany (K.W.); Heart Failure and Circulatory Support Program, George Washington University School of Medicine, DC (G.S.P.); and Johns Hopkins School of Public Health, Baltimore, MD (A.G.)
| | - Asieh Golozar
- From the Division of Cardiology, Department of Medicine (K.W., G.S.P., K.S., A.S., G.G., S.D.R., R.G.W.) and Division of Magnetic Resonance Research, Department of Radiology (K.W., M.S., P.A.B.), Johns Hopkins University School of Medicine, Baltimore, MD; Philips Healthcare Germany, Hamburg, Germany (K.W.); Heart Failure and Circulatory Support Program, George Washington University School of Medicine, DC (G.S.P.); and Johns Hopkins School of Public Health, Baltimore, MD (A.G.)
| | - Angela Steinberg
- From the Division of Cardiology, Department of Medicine (K.W., G.S.P., K.S., A.S., G.G., S.D.R., R.G.W.) and Division of Magnetic Resonance Research, Department of Radiology (K.W., M.S., P.A.B.), Johns Hopkins University School of Medicine, Baltimore, MD; Philips Healthcare Germany, Hamburg, Germany (K.W.); Heart Failure and Circulatory Support Program, George Washington University School of Medicine, DC (G.S.P.); and Johns Hopkins School of Public Health, Baltimore, MD (A.G.)
| | - Gary Gerstenblith
- From the Division of Cardiology, Department of Medicine (K.W., G.S.P., K.S., A.S., G.G., S.D.R., R.G.W.) and Division of Magnetic Resonance Research, Department of Radiology (K.W., M.S., P.A.B.), Johns Hopkins University School of Medicine, Baltimore, MD; Philips Healthcare Germany, Hamburg, Germany (K.W.); Heart Failure and Circulatory Support Program, George Washington University School of Medicine, DC (G.S.P.); and Johns Hopkins School of Public Health, Baltimore, MD (A.G.)
| | - Stuart D Russell
- From the Division of Cardiology, Department of Medicine (K.W., G.S.P., K.S., A.S., G.G., S.D.R., R.G.W.) and Division of Magnetic Resonance Research, Department of Radiology (K.W., M.S., P.A.B.), Johns Hopkins University School of Medicine, Baltimore, MD; Philips Healthcare Germany, Hamburg, Germany (K.W.); Heart Failure and Circulatory Support Program, George Washington University School of Medicine, DC (G.S.P.); and Johns Hopkins School of Public Health, Baltimore, MD (A.G.)
| | - Robert G Weiss
- From the Division of Cardiology, Department of Medicine (K.W., G.S.P., K.S., A.S., G.G., S.D.R., R.G.W.) and Division of Magnetic Resonance Research, Department of Radiology (K.W., M.S., P.A.B.), Johns Hopkins University School of Medicine, Baltimore, MD; Philips Healthcare Germany, Hamburg, Germany (K.W.); Heart Failure and Circulatory Support Program, George Washington University School of Medicine, DC (G.S.P.); and Johns Hopkins School of Public Health, Baltimore, MD (A.G.).
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Hooijmans MT, Doorenweerd N, Baligand C, Verschuuren JJGM, Ronen I, Niks EH, Webb AG, Kan HE. Spatially localized phosphorous metabolism of skeletal muscle in Duchenne muscular dystrophy patients: 24-month follow-up. PLoS One 2017; 12:e0182086. [PMID: 28763477 PMCID: PMC5538641 DOI: 10.1371/journal.pone.0182086] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 07/12/2017] [Indexed: 12/29/2022] Open
Abstract
Objectives To assess the changes in phosphodiester (PDE)-levels, detected by 31P magnetic resonance spectroscopy (MRS), over 24-months to determine the potential of PDE as marker for muscle tissue changes in Duchenne Muscular Dystrophy (DMD) patients. Methods Spatially resolved phosphorous datasets were acquired in the right lower leg of 18 DMD patients (range: 5–15.4 years) and 12 age-matched healthy controls (range: 5–14 years) at three time-points (baseline, 12-months, and 24-months) using a 7T MR-System (Philips Achieva). 3-point Dixon images were acquired at 3T (Philips Ingenia) to determine muscle fat fraction. Analyses were done for six muscles that represent different stages of muscle wasting. Differences between groups and time-points were assessed with non-parametric tests with correction for multiple comparisons. Coefficient of variance (CV) were determined for PDE in four healthy adult volunteers in high and low signal-to-noise ratio (SNR) datasets. Results PDE-levels were significantly higher (two-fold) in DMD patients compared to controls in all analyzed muscles at almost every time point and did not change over the study period. Fat fraction was significantly elevated in all muscles at all time points compared to healthy controls, and increased significantly over time, except in the tibialis posterior muscle. The mean within subject CV for PDE-levels was 4.3% in datasets with high SNR (>10:1) and 5.7% in datasets with low SNR. Discussion and conclusion The stable two-fold increase in PDE-levels found in DMD patients in muscles with different levels of muscle wasting over 2-year time, including DMD patients as young as 5.5 years-old, suggests that PDE-levels may increase very rapidly early in the disease process and remain elevated thereafter. The low CV values in high and low SNR datasets show that PDE-levels can be accurately and reproducibly quantified in all conditions. Our data confirms the great potential of PDE as a marker for muscle tissue changes in DMD patients.
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Affiliation(s)
- M. T. Hooijmans
- Dept of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
- * E-mail:
| | - N. Doorenweerd
- Dept of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
- John Walton Muscular Dystrophy Research Centre, Newcastle University, Newcastle Upon Tyne, United Kingdom
| | - C. Baligand
- Dept of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
| | | | - I. Ronen
- Dept of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
| | - E. H. Niks
- Dept of Neurology, Leiden University Medical Center, Leiden, The Netherlands
| | - A. G. Webb
- Dept of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
| | - H. E. Kan
- Dept of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
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Liu Y, Mei X, Li J, Lai N, Yu X. Mitochondrial function assessed by 31P MRS and BOLD MRI in non-obese type 2 diabetic rats. Physiol Rep 2017; 4:4/15/e12890. [PMID: 27511984 PMCID: PMC4985553 DOI: 10.14814/phy2.12890] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 07/19/2016] [Indexed: 12/23/2022] Open
Abstract
The study aims to characterize age‐associated changes in skeletal muscle bioenergetics by evaluating the response to ischemia‐reperfusion in the skeletal muscle of the Goto‐Kakizaki (GK) rats, a rat model of non‐obese type 2 diabetes (T2D). 31P magnetic resonance spectroscopy (MRS) and blood oxygen level‐dependent (BOLD) MRI was performed on the hindlimb of young (12 weeks) and adult (20 weeks) GK and Wistar (control) rats. 31P‐MRS and BOLD‐MRI data were acquired continuously during an ischemia and reperfusion protocol to quantify changes in phosphate metabolites and muscle oxygenation. The time constant of phosphocreatine recovery, an index of mitochondrial oxidative capacity, was not statistically different between GK rats (60.8 ± 13.9 sec in young group, 83.7 ± 13.0 sec in adult group) and their age‐matched controls (62.4 ± 11.6 sec in young group, 77.5 ± 7.1 sec in adult group). During ischemia, baseline‐normalized BOLD‐MRI signal was significantly lower in GK rats than in their age‐matched controls. These results suggest that insulin resistance leads to alterations in tissue metabolism without impaired mitochondrial oxidative capacity in GK rats.
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Affiliation(s)
- Yuchi Liu
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio Case Center for Imaging Research, Case Western Reserve University, Cleveland, Ohio
| | - Xunbai Mei
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio Case Center for Imaging Research, Case Western Reserve University, Cleveland, Ohio
| | - Jielei Li
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio
| | - Nicola Lai
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio Department of Electrical and Computer Engineering and Biomedical Engineering Institute, Old Dominion University, Norfolk, Virginia
| | - Xin Yu
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio Case Center for Imaging Research, Case Western Reserve University, Cleveland, Ohio Department of Radiology, Case Western Reserve University, Cleveland, Ohio Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, Ohio
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Fitzgerald LF, Christie AD, Kent JA. Heterogeneous effects of old age on human muscle oxidative capacity in vivo: a systematic review and meta-analysis. Appl Physiol Nutr Metab 2016; 41:1137-1145. [DOI: 10.1139/apnm-2016-0195] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Despite intensive efforts to understand the extent to which skeletal muscle mitochondrial capacity changes in older humans, the answer to this important question remains unclear. To determine what the preponderance of evidence from in vivo studies suggests, we conducted a systematic review and meta-analysis of the effects of age on muscle oxidative capacity as measured noninvasively by magnetic resonance spectroscopy. A secondary aim was to examine potential moderators contributing to differences in results across studies, including muscle group, physical activity status, and sex. Candidate papers were identified from PubMed searches (n = 3561 papers) and the reference lists of relevant papers. Standardized effects (Hedges’ g) were calculated for age and each moderator using data from the 22 studies that met the inclusion criteria (n = 28 effects). Effects were coded as positive when older (age, ≥55 years) adults had higher muscle oxidative capacity than younger (age, 20–45 years) adults. The overall effect of age on oxidative capacity was positive (g = 0.171, p < 0.001), indicating modestly greater oxidative capacity in old. Notably, there was significant heterogeneity in this result (Q = 245.8, p < 0.001; I2 = ∼70%–90%). Muscle group, physical activity, and sex were all significant moderators of oxidative capacity (p ≤ 0.029). This analysis indicates that the current body of literature does not support a de facto decrease of in vivo muscle oxidative capacity in old age. The heterogeneity of study results and identification of significant moderators provide clarity regarding apparent discrepancies in the literature, and indicate the importance of accounting for these variables when examining purported age-related differences in muscle oxidative capacity.
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Affiliation(s)
- Liam F. Fitzgerald
- Department of Kinesiology, University of Massachusetts Amherst, MA 01003, USA
| | - Anita D. Christie
- Department of Human Physiology, University of Oregon, Eugene, OR 97403, USA
| | - Jane A. Kent
- Department of Kinesiology, University of Massachusetts Amherst, MA 01003, USA
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Kent JA, Fitzgerald LF. In vivo mitochondrial function in aging skeletal muscle: capacity, flux, and patterns of use. J Appl Physiol (1985) 2016; 121:996-1003. [PMID: 27539499 DOI: 10.1152/japplphysiol.00583.2016] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 08/17/2016] [Indexed: 01/31/2023] Open
Abstract
Because of the fundamental dependence of mammalian life on adequate mitochondrial function, the question of how and why mitochondria change in old age is the target of intense study. Given the importance of skeletal muscle for the support of mobility and health, this question extends to the need to understand mitochondrial changes in the muscle of older adults, as well. We and others have focused on clarifying the age-related changes in human skeletal muscle mitochondrial function in vivo. These changes include both the maximal capacity for oxidative production of energy (ATP), as well as the relative use of mitochondrial ATP production for powering muscular activity. It has been known for nearly 50 yr that muscle mitochondrial content is highly plastic; exercise training can induce an ∼2-fold increase in mitochondrial content, while disuse has the opposite effect. Here, we suggest that a portion of the age-related changes in mitochondrial function that have been reported are likely the result of behavioral effects, as physical activity influences have not always been accounted for. Further, there is emerging evidence that various muscles may be affected differently by age-related changes in physical activity and movement patterns. In this review, we will focus on age-related changes in oxidative capacity and flux measured in vivo in human skeletal muscle.
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Affiliation(s)
- Jane A Kent
- Muscle Physiology Laboratory, Department of Kinesiology, University of Massachusetts Amherst, Amherst, Massachusetts
| | - Liam F Fitzgerald
- Muscle Physiology Laboratory, Department of Kinesiology, University of Massachusetts Amherst, Amherst, Massachusetts
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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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van der Zwaard S, de Ruiter CJ, Noordhof DA, Sterrenburg R, Bloemers FW, de Koning JJ, Jaspers RT, van der Laarse WJ. Maximal oxygen uptake is proportional to muscle fiber oxidative capacity, from chronic heart failure patients to professional cyclists. J Appl Physiol (1985) 2016; 121:636-45. [PMID: 27445298 DOI: 10.1152/japplphysiol.00355.2016] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 07/19/2016] [Indexed: 12/25/2022] Open
Abstract
V̇o2 max during whole body exercise is presumably constrained by oxygen delivery to mitochondria rather than by mitochondria's ability to consume oxygen. Humans and animals have been reported to exploit only 60-80% of their mitochondrial oxidative capacity at maximal oxygen uptake (V̇o2 max). However, ex vivo quantification of mitochondrial overcapacity is complicated by isolation or permeabilization procedures. An alternative method for estimating mitochondrial oxidative capacity is via enzyme histochemical quantification of succinate dehydrogenase (SDH) activity. We determined to what extent V̇o2 max attained during cycling exercise differs from mitochondrial oxidative capacity predicted from SDH activity of vastus lateralis muscle in chronic heart failure patients, healthy controls, and cyclists. V̇o2 max was assessed in 20 healthy subjects and 28 cyclists, and SDH activity was determined from biopsy cryosections of vastus lateralis using quantitative histochemistry. Similar data from our laboratory of 14 chronic heart failure patients and 6 controls were included. Mitochondrial oxidative capacity was predicted from SDH activity using estimated skeletal muscle mass and the relationship between ex vivo fiber V̇o2 max and SDH activity of isolated single muscle fibers and myocardial trabecula under hyperoxic conditions. Mitochondrial oxidative capacity predicted from SDH activity was related (r(2) = 0.89, P < 0.001) to V̇o2 max measured during cycling in subjects with V̇o2 max ranging from 9.8 to 79.0 ml·kg(-1)·min(-1) V̇o2 max measured during cycling was on average 90 ± 14% of mitochondrial oxidative capacity. We conclude that human V̇o2 max is related to mitochondrial oxidative capacity predicted from skeletal muscle SDH activity. Mitochondrial oxidative capacity is likely marginally limited by oxygen supply to mitochondria.
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Affiliation(s)
- Stephan van der Zwaard
- Faculty of Behavioural and Movement Sciences, Department of Human Movement Sciences, Vrije Universiteit Amsterdam, MOVE Research Institute Amsterdam, Amsterdam, The Netherlands;
| | - C Jo de Ruiter
- Faculty of Behavioural and Movement Sciences, Department of Human Movement Sciences, Vrije Universiteit Amsterdam, MOVE Research Institute Amsterdam, Amsterdam, The Netherlands
| | - Dionne A Noordhof
- Faculty of Behavioural and Movement Sciences, Department of Human Movement Sciences, Vrije Universiteit Amsterdam, MOVE Research Institute Amsterdam, Amsterdam, The Netherlands
| | - Renske Sterrenburg
- Faculty of Behavioural and Movement Sciences, Department of Human Movement Sciences, Vrije Universiteit Amsterdam, MOVE Research Institute Amsterdam, Amsterdam, The Netherlands
| | - Frank W Bloemers
- Department of Trauma Surgery, VU University Medical Center Amsterdam, Amsterdam, The Netherlands
| | - Jos J de Koning
- Faculty of Behavioural and Movement Sciences, Department of Human Movement Sciences, Vrije Universiteit Amsterdam, MOVE Research Institute Amsterdam, Amsterdam, The Netherlands
| | - Richard T Jaspers
- Faculty of Behavioural and Movement Sciences, Department of Human Movement Sciences, Vrije Universiteit Amsterdam, MOVE Research Institute Amsterdam, Amsterdam, The Netherlands; Laboratory for Myology, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, MOVE Research Institute Amsterdam, Amsterdam, The Netherlands; and
| | - Willem J van der Laarse
- Department of Physiology, Institute for Cardiovascular Research, VU University Medical Center Amsterdam, Amsterdam, The Netherlands
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Béchir N, Pecchi E, Vilmen C, Le Fur Y, Amthor H, Bernard M, Bendahan D, Giannesini B. ActRIIB blockade increases force-generating capacity and preserves energy supply in exercising mdx mouse muscle in vivo. FASEB J 2016; 30:3551-3562. [PMID: 27416839 DOI: 10.1096/fj.201600271rr] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 06/28/2016] [Indexed: 11/11/2022]
Abstract
Postnatal blockade of the activin type IIB receptor (ActRIIB) represents a promising therapeutic strategy for counteracting dystrophic muscle wasting. However, its impact on muscle function and bioenergetics remains poorly documented in physiologic conditions. We have investigated totally noninvasively the effect of 8-wk administration of either soluble ActRIIB signaling inhibitor (sActRIIB-Fc) or vehicle PBS (control) on gastrocnemius muscle force-generating capacity, energy metabolism, and anatomy in dystrophic mdx mice using magnetic resonance (MR) imaging and dynamic [31P]-MR spectroscopy ([31P]-MRS) in vivo ActRIIB inhibition increased muscle volume (+33%) without changing fiber-type distribution, and increased basal animal oxygen consumption (+22%) and energy expenditure (+23%). During an in vivo standardized fatiguing exercise, maximum and total absolute contractile forces were larger (+40 and 24%, respectively) in sActRIIB-Fc treated animals, whereas specific force-generating capacity and fatigue resistance remained unaffected. Furthermore, sActRIIB-Fc administration did not alter metabolic fluxes, ATP homeostasis, or contractile efficiency during the fatiguing bout of exercise, although it dramatically reduced the intrinsic mitochondrial capacity for producing ATP. Overall, sActRIIB-Fc treatment increased muscle mass and strength without altering the fundamental weakness characteristic of dystrophic mdx muscle. These data support the clinical interest of ActRIIB blockade for reversing dystrophic muscle wasting.-Béchir, N., Pecchi, E., Vilmen, C., Le Fur, Y., Amthor, H., Bernard, M., Bendahan, D., Giannesini, B. ActRIIB blockade increases force-generating capacity and preserves energy supply in exercising mdx mouse muscle in vivo.
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Affiliation(s)
- Nelly Béchir
- Aix-Marseille Université, Centre National de la Recherche Scientifique, Centre de Résonance Magnétique Biologique et Médicale, Unité Mixte de Recherche 7339, Marseille, France
| | - Emilie Pecchi
- Aix-Marseille Université, Centre National de la Recherche Scientifique, Centre de Résonance Magnétique Biologique et Médicale, Unité Mixte de Recherche 7339, Marseille, France
| | - Christophe Vilmen
- Aix-Marseille Université, Centre National de la Recherche Scientifique, Centre de Résonance Magnétique Biologique et Médicale, Unité Mixte de Recherche 7339, Marseille, France
| | - Yann Le Fur
- Aix-Marseille Université, Centre National de la Recherche Scientifique, Centre de Résonance Magnétique Biologique et Médicale, Unité Mixte de Recherche 7339, Marseille, France
| | - Helge Amthor
- Université de Versailles Saint-Quentin-en-Yvelines, Unités de Formation et de Recherche des Sciences de la Santé, INSERM U1179, Laboratoire International Associé, Biologie Appliquée Handicap Neuromusculaire, Cellules Souches Mésenchymateuses, Saint Quentin en Yvelines Therapeutics, Montigny-le-Bretonneux, France; and Service Génétique Médicale, Centre Hospitalier Universitaire Necker-Enfants Malades, Université Paris Descartes, Paris, France
| | - Monique Bernard
- Aix-Marseille Université, Centre National de la Recherche Scientifique, Centre de Résonance Magnétique Biologique et Médicale, Unité Mixte de Recherche 7339, Marseille, France
| | - David Bendahan
- Aix-Marseille Université, Centre National de la Recherche Scientifique, Centre de Résonance Magnétique Biologique et Médicale, Unité Mixte de Recherche 7339, Marseille, France
| | - Benoît Giannesini
- Aix-Marseille Université, Centre National de la Recherche Scientifique, Centre de Résonance Magnétique Biologique et Médicale, Unité Mixte de Recherche 7339, Marseille, France;
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Béchir N, Pecchi É, Relizani K, Vilmen C, Le Fur Y, Bernard M, Amthor H, Bendahan D, Giannesini B. Mitochondrial impairment induced by postnatal ActRIIB blockade does not alter function and energy status in exercising mouse glycolytic muscle in vivo. Am J Physiol Endocrinol Metab 2016; 310:E539-49. [PMID: 26837807 DOI: 10.1152/ajpendo.00370.2015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 01/24/2016] [Indexed: 11/22/2022]
Abstract
Because it leads to a rapid and massive muscle hypertrophy, postnatal blockade of the activin type IIB receptor (ActRIIB) is a promising therapeutic strategy for counteracting muscle wasting. However, the functional consequences remain very poorly documented in vivo. Here, we have investigated the impact of 8-wk ActRIIB blockade with soluble receptor (sActRIIB-Fc) on gastrocnemius muscle anatomy, energy metabolism, and force-generating capacity in wild-type mice, using totally noninvasive magnetic resonance imaging (MRI) and dynamic(31)P-MRS. Compared with vehicle (PBS) control, sActRIIB-Fc treatment resulted in a dramatic increase in body weight (+29%) and muscle volume (+58%) calculated from hindlimb MR imaging, but did not alter fiber type distribution determined via myosin heavy chain isoform analysis. In resting muscle, sActRIIB-Fc treatment induced acidosis and PCr depletion, thereby suggesting reduced tissue oxygenation. During an in vivo fatiguing exercise (6-min repeated maximal isometric contraction electrically induced at 1.7 Hz), maximal and total absolute forces were larger in sActRIIB-Fc treated animals (+26 and +12%, respectively), whereas specific force and fatigue resistance were lower (-30 and -37%, respectively). Treatment with sActRIIB-Fc further decreased the maximal rate of oxidative ATP synthesis (-42%) and the oxidative capacity (-34%), but did not alter the bioenergetics status in contracting muscle. Our findings demonstrate in vivo that sActRIIB-Fc treatment increases absolute force-generating capacity and reduces mitochondrial function in glycolytic gastrocnemius muscle, but this reduction does not compromise energy status during sustained activity. Overall, these data support the clinical interest of postnatal ActRIIB blockade.
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Affiliation(s)
- Nelly Béchir
- Aix-Marseille Université, CNRS, Centre de Résonance Magnétique Biologique et Médicale, UMR 7339, 13385, Marseille, France; and
| | - Émilie Pecchi
- Aix-Marseille Université, CNRS, Centre de Résonance Magnétique Biologique et Médicale, UMR 7339, 13385, Marseille, France; and
| | - Karima Relizani
- Université de Versailles Saint-Quentin-en-Yvelines, UFR des sciences de la santé, INSERM U1179, LIA BAHN CSM, SQY Therapeutics, 78180 Montigny-le-Bretonneux, France
| | - Christophe Vilmen
- Aix-Marseille Université, CNRS, Centre de Résonance Magnétique Biologique et Médicale, UMR 7339, 13385, Marseille, France; and
| | - Yann Le Fur
- Aix-Marseille Université, CNRS, Centre de Résonance Magnétique Biologique et Médicale, UMR 7339, 13385, Marseille, France; and
| | - Monique Bernard
- Aix-Marseille Université, CNRS, Centre de Résonance Magnétique Biologique et Médicale, UMR 7339, 13385, Marseille, France; and
| | - Helge Amthor
- Université de Versailles Saint-Quentin-en-Yvelines, UFR des sciences de la santé, INSERM U1179, LIA BAHN CSM, SQY Therapeutics, 78180 Montigny-le-Bretonneux, France
| | - David Bendahan
- Aix-Marseille Université, CNRS, Centre de Résonance Magnétique Biologique et Médicale, UMR 7339, 13385, Marseille, France; and
| | - Benoît Giannesini
- Aix-Marseille Université, CNRS, Centre de Résonance Magnétique Biologique et Médicale, UMR 7339, 13385, Marseille, France; and
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Campbell MD, Marcinek DJ. Evaluation of in vivo mitochondrial bioenergetics in skeletal muscle using NMR and optical methods. BIOCHIMICA ET BIOPHYSICA ACTA 2016; 1862:716-724. [PMID: 26708941 PMCID: PMC4788529 DOI: 10.1016/j.bbadis.2015.12.019] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 11/20/2015] [Accepted: 12/16/2015] [Indexed: 12/13/2022]
Abstract
It is now clear that mitochondria are involved as either a cause or consequence of many chronic diseases. This central role of the mitochondria is due to their position in the cell as important integrators of cellular energetics and signaling. Mitochondrial function affects many aspects of the cellular environment such as redox homeostasis and calcium signaling, which then also exert control over mitochondrial function. This complex dynamic between mitochondrial function and the cellular environment highlights the value of examining mitochondria in vivo in the intact physiological environment. This review discusses NMR and optical approaches used to measure mitochondria ATP and oxygen fluxes that provide in vivo measures of mitochondrial capacity and quality in animal and human models. Combining these in vivo measurements with more traditional ex vivo analyses can lead to new insights into the importance of the cellular environment in controlling mitochondrial function under pathological conditions. Interpretation and underlying assumptions for each technique are discussed with the goal of providing an overview of some of the most common approaches used to measure in vivo mitochondrial function encountered in the literature.
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Affiliation(s)
- Matthew D Campbell
- University of Washington, Seattle, 850 Republican St., Brotman D142, Seattle, WA 98109, USA.
| | - David J Marcinek
- University of Washington, Seattle, 850 Republican St., Brotman D142, Seattle, WA 98109, USA.
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Zhao J, Guan H, Li M, Gu H, Qin J, Wu X. Significance of the ADC ratio in the differential diagnosis of breast lesions. Acta Radiol 2016; 57:422-9. [PMID: 26071495 DOI: 10.1177/0284185115590286] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Accepted: 05/11/2015] [Indexed: 12/21/2022]
Abstract
BACKGROUND Magnetic resonance imaging (MRI) has high sensitivity but low specificity for breast cancer, and consequently, new techniques to improve the specificity of breast MRI in diagnosing breast cancer are under development. PURPOSE To assess the ability of the apparent diffusion coefficient (ADC) compared with the ADC ratio (ADCr) to differentially diagnose benign compared with malignant breast lesions. MATERIAL AND METHODS Forty-eight women with breast lesions (average age, 45 years) underwent MRI scanning including T1-weighted dynamic contrast-enhanced (DCE) scanning and diffusion-weighted imaging (DWI). The average ADC and ADCr values for both lesions and pectoralis major muscles (ADCrmuscle and ADCrmuscle) were measured in patients with malignant (n = 25) and benign (n = 23) breast lesions. The ADCr of the contralateral breast (ADCr contralateral) was also evaluated. All histology was confirmed by pathological analysis of biopsied tissue. ADC and ADCr values were analyzed using receiver-operating characteristic (ROC) curves. RESULTS For benign lesions compared with malignant lesions, lesion-side ADC was 1.45 vs. 1.05, respectively (P < 0.001), normal-side ADC was 1.82 vs.1.64 (P = 0.002), ADCrmuscle was 1.35 vs. 0.9 (P < 0.001), and ADCrcontralateral was 0.79 vs. 0.64 (P = 0.001). ADCrmuscle showed higher sensitivity (82.61%) and specificity (96.00%) than ADCrcontralateral (60.87% and 92.00%, respectively) and ADC (69.57% and 96.00%) for discriminating malignant from benign lesions. The AUC using ADCrmuscle had higher discriminatory power (0.92, P < 0.001) for malignant versus benign breast lesions compared with either ADC (0.82, P < 0.001) or ADCrcontralateral (0.78, P = 0.001). CONCLUSION The ADCrmuscle value showed higher sensitivity and specificity and improved diagnostic accuracy compared with either ADC or ADCrcontralateral in differentiating benign from malignant breast lesions.
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Affiliation(s)
- Jinli Zhao
- Department of Radiology, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, PR China
| | - Haitao Guan
- Department of Ultrasound, The Third People's Hospital of Nantong, Nantong, Jiangsu Province, PR China
| | - Minda Li
- Department of Radiology, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, PR China
| | - Hongmei Gu
- Department of Radiology, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, PR China
| | - Jufeng Qin
- Department of Radiology, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, PR China
| | - Xianhua Wu
- Department of Radiology, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, PR China
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Johnson ML, Distelmaier K, Lanza IR, Irving BA, Robinson MM, Konopka AR, Shulman GI, Nair KS. Mechanism by Which Caloric Restriction Improves Insulin Sensitivity in Sedentary Obese Adults. Diabetes 2016; 65:74-84. [PMID: 26324180 PMCID: PMC4686951 DOI: 10.2337/db15-0675] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 08/26/2015] [Indexed: 12/12/2022]
Abstract
Caloric restriction (CR) improves insulin sensitivity and reduces the incidence of diabetes in obese individuals. The underlying mechanisms whereby CR improves insulin sensitivity are not clear. We evaluated the effect of 16 weeks of CR on whole-body insulin sensitivity by pancreatic clamp before and after CR in 11 obese participants (BMI = 35 kg/m(2)) compared with 9 matched control subjects (BMI = 34 kg/m(2)). Compared with the control subjects, CR increased the glucose infusion rate needed to maintain euglycemia during hyperinsulinemia, indicating enhancement of peripheral insulin sensitivity. This improvement in insulin sensitivity was not accompanied by changes in skeletal muscle mitochondrial oxidative capacity or oxidant emissions, nor were there changes in skeletal muscle ceramide, diacylglycerol, or amino acid metabolite levels. However, CR lowered insulin-stimulated thioredoxin-interacting protein (TXNIP) levels and enhanced nonoxidative glucose disposal. These results support a role for TXNIP in mediating the improvement in peripheral insulin sensitivity after CR.
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Affiliation(s)
- Matthew L Johnson
- Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, MN
| | - Klaus Distelmaier
- Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, MN
| | - Ian R Lanza
- Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, MN
| | - Brian A Irving
- Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, MN
| | - Matthew M Robinson
- Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, MN
| | - Adam R Konopka
- Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, MN
| | - Gerald I Shulman
- Howard Hughes Medical Institute and the Departments of Medicine and Cellular & Molecular Physiology, Yale University School of Medicine, New Haven, CT
| | - K Sreekumaran Nair
- Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, MN
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Ryan ZC, Craig TA, Folmes CD, Wang X, Lanza IR, Schaible NS, Salisbury JL, Nair KS, Terzic A, Sieck GC, Kumar R. 1α,25-Dihydroxyvitamin D3 Regulates Mitochondrial Oxygen Consumption and Dynamics in Human Skeletal Muscle Cells. J Biol Chem 2015; 291:1514-28. [PMID: 26601949 DOI: 10.1074/jbc.m115.684399] [Citation(s) in RCA: 146] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Indexed: 12/16/2022] Open
Abstract
Muscle weakness and myopathy are observed in vitamin D deficiency and chronic renal failure, where concentrations of the active vitamin D3 metabolite, 1α,25-dihydroxyvitamin D3 (1α,25(OH)2D3), are low. To evaluate the mechanism of action of 1α,25(OH)2D3 in skeletal muscle, we examined mitochondrial oxygen consumption, dynamics, and biogenesis and changes in expression of nuclear genes encoding mitochondrial proteins in human skeletal muscle cells following treatment with 1α,25(OH)2D3. The mitochondrial oxygen consumption rate (OCR) increased in 1α,25(OH)2D3-treated cells. Vitamin D3 metabolites lacking a 1α-hydroxyl group (vitamin D3, 25-hydroxyvitamin D3, and 24R,25-dihydroxyvitamin D3) decreased or failed to increase OCR. 1α-Hydroxyvitamin D3 did not increase OCR. In 1α,25(OH)2D3-treated cells, mitochondrial volume and branching and expression of the pro-fusion protein OPA1 (optic atrophy 1) increased, whereas expression of the pro-fission proteins Fis1 (fission 1) and Drp1 (dynamin 1-like) decreased. Phosphorylated pyruvate dehydrogenase (PDH) (Ser-293) and PDH kinase 4 (PDK4) decreased in 1α,25(OH)2D3-treated cells. There was a trend to increased PDH activity in 1α,25(OH)2D3-treated cells (p = 0.09). 83 nuclear mRNAs encoding mitochondrial proteins were changed following 1α,25(OH)2D3 treatment; notably, PDK4 mRNA decreased, and PDP2 mRNA increased. MYC, MAPK13, and EPAS1 mRNAs, which encode proteins that regulate mitochondrial biogenesis, were increased following 1α,25(OH)2D3 treatment. Vitamin D receptor-dependent changes in the expression of 1947 mRNAs encoding proteins involved in muscle contraction, focal adhesion, integrin, JAK/STAT, MAPK, growth factor, and p53 signaling pathways were observed following 1α,25(OH)2D3 treatment. Five micro-RNAs were induced or repressed by 1α,25(OH)2D3. 1α,25(OH)2D3 regulates mitochondrial function, dynamics, and enzyme function, which are likely to influence muscle strength.
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Affiliation(s)
| | | | | | | | | | | | - Jeffrey L Salisbury
- Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, Minnesota 55905
| | | | | | | | - Rajiv Kumar
- From the Departments of Medicine, Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, Minnesota 55905
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Yanagisawa O, Kurihara T. Intramuscular water movement during and after isometric muscle contraction: evaluation at different exercise intensities. Clin Physiol Funct Imaging 2015; 36:368-75. [DOI: 10.1111/cpf.12239] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2014] [Accepted: 01/27/2015] [Indexed: 11/30/2022]
Affiliation(s)
- Osamu Yanagisawa
- Sports & Health Management Program; Faculty of Business & Information Sciences; Jobu University; Isesaki Japan
| | - Toshiyuki Kurihara
- Faculty of Sport and Health Science; Ritsumeikan University; Kusatsu Japan
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Lalia AZ, Johnson ML, Jensen MD, Hames KC, Port JD, Lanza IR. Effects of Dietary n-3 Fatty Acids on Hepatic and Peripheral Insulin Sensitivity in Insulin-Resistant Humans. Diabetes Care 2015; 38:1228-37. [PMID: 25852206 PMCID: PMC4477338 DOI: 10.2337/dc14-3101] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Accepted: 03/05/2015] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Dietary n-3 polyunsaturated fatty acids, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), prevent insulin resistance and stimulate mitochondrial biogenesis in rodents, but the findings of translational studies in humans are thus far ambiguous. The aim of this study was to evaluate the influence of EPA and DHA on insulin sensitivity, insulin secretion, and muscle mitochondrial function in insulin-resistant, nondiabetic humans using a robust study design and gold-standard measurements. RESEARCH DESIGN AND METHODS Thirty-one insulin-resistant adults received 3.9 g/day EPA+DHA or placebo for 6 months in a randomized double-blind study. Hyperinsulinemic-euglycemic clamp with somatostatin was used to assess hepatic and peripheral insulin sensitivity. Postprandial glucose disposal and insulin secretion were measured after a meal. Measurements were performed at baseline and after 6 months of treatment. Abdominal fat distribution was evaluated by MRI. Muscle oxidative capacity was measured in isolated mitochondria using high-resolution respirometry and noninvasively by magnetic resonance spectroscopy. RESULTS Compared with placebo, EPA+DHA did not alter peripheral insulin sensitivity, postprandial glucose disposal, or insulin secretion. Hepatic insulin sensitivity, determined from the suppression of endogenous glucose production by insulin, exhibited a small but significant improvement with EPA+DHA compared with placebo. Muscle mitochondrial function was unchanged by EPA+DHA or placebo. CONCLUSIONS This study demonstrates that dietary EPA+DHA does not improve peripheral glucose disposal, insulin secretion, or skeletal muscle mitochondrial function in insulin-resistant nondiabetic humans. There was a modest improvement in hepatic insulin sensitivity with EPA+DHA, but this was not associated with any improvements in clinically meaningful outcomes.
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Affiliation(s)
- Antigoni Z Lalia
- Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, MN
| | - Matthew L Johnson
- Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, MN
| | - Michael D Jensen
- Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, MN
| | - Kazanna C Hames
- Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, MN
| | - John D Port
- Division of Radiology, Mayo Clinic College of Medicine, Rochester, MN
| | - Ian R Lanza
- Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, MN
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