1
|
Koutlas A, Smilios I, Kokkinou EM, Myrkos A, Kounoupis A, Dipla K, Zafeiridis A. NIRS-Derived Muscle-Deoxygenation and Microvascular Reactivity During Occlusion-Reperfusion at Rest Are Associated With Whole-Body Aerobic Fitness. RESEARCH QUARTERLY FOR EXERCISE AND SPORT 2024; 95:127-139. [PMID: 36689603 DOI: 10.1080/02701367.2022.2159309] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 12/12/2022] [Indexed: 06/17/2023]
Abstract
Purpose: Near-infrared spectroscopy (NIRS) indices during arterial occlusion-reperfusion maneuver have been used to examine the muscle's oxidative metabolism and microvascular function-important determinants of whole-body aerobic-fitness. The association of NIRS-derived parameters with whole-body VO2max was previously examined using a method requiring exercise (or electrical stimulation) followed by multiple arterial occlusions. We examined whether NIRS-derived indices of muscle deoxygenation and microvascular reactivity assessed during a single occlusion-reperfusion at rest are (a) associated with maximal/submaximal indices of whole-body aerobic-fitness and (b) could discriminate individuals with different VO2max. We, also, investigated which NIRS-parameter during occlusion-reperfusion correlates best with whole-body aerobic-fitness. Methods: Twenty-five young individuals performed an arterial occlusion-reperfusion at rest. Changes in oxygenated- and deoxygenated-hemoglobin (O2Hb and HHb, respectively) in vastus-lateralis were monitored; adipose tissue thickness (ATT) at NIRS-application was assessed. Participants also underwent a maximal incremental exercise test for VO2max, maximal aerobic velocity (MAV), and ventilatory-thresholds (VTs) assessments. Results: The HHbslope and HHbmagnitude of increase (occlusion-phase) and O2Hbmagnitude of increase (reperfusion-phase) were strongly correlated with VO2max (r = .695-.763, p < .001) and moderately with MAV (r = .468-.530; p < .05). O2Hbmagnitude was moderately correlated with VTs (r = .399-.414; p < .05). After controlling for ATT, the correlations remained significant for VO2max (r = .672-.704; p < .001) and MAV (r = .407; p < .05). Individuals in the high percentiles after median and tritile splits for HHbslope and O2Hbmagnitude had significantly greater VO2max vs. those in low percentiles (p < .01-.05). The HHbslope during occlusion was the best predictor of VO2max. Conclusion: NIRS-derived muscle deoxygenation/reoxygenation indices during a single arterial occlusion-reperfusion maneuver are strongly associated with whole-body maximal indices of aerobic-fitness (VO2max, MAV) and may discriminate individuals with different VO2max.
Collapse
|
2
|
Brzęk P, Roussel D, Konarzewski M. Mice selected for a high basal metabolic rate evolved larger guts but not more efficient mitochondria. Proc Biol Sci 2022; 289:20220719. [PMID: 35858057 PMCID: PMC9277295 DOI: 10.1098/rspb.2022.0719] [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: 12/25/2022] Open
Abstract
Intra-specific variation in both the basal metabolic rate (BMR) and mitochondrial efficiency (the amount of ATP produced per unit of oxygen consumed) has profound evolutionary and ecological consequences. However, the functional mechanisms responsible for this variation are not fully understood. Mitochondrial efficiency is negatively correlated with BMR at the interspecific level but it is positively correlated with performance capacity at the intra-specific level. This discrepancy is surprising, as theories explaining the evolution of endothermy assume a positive correlation between BMR and performance capacity. Here, we quantified mitochondrial oxidative phosphorylation activity and efficiency in two lines of laboratory mice divergently selected for either high (H-BMR) or low (L-BMR) levels of BMR. H-BMR mice had larger livers and kidneys (organs that are important predictors of BMR). H-BMR mice also showed higher oxidative phosphorylation activity in liver mitochondria but this difference can be hypothesized to be a direct effect of selection only if the heritability of this trait is low. However, mitochondrial efficiency in all studied organs did not differ between the two lines. We conclude that the rapid evolution of BMR can reflect changes in organ size rather than mitochondrial properties, and does not need to be accompanied obligatorily by changes in mitochondrial efficiency.
Collapse
Affiliation(s)
- Paweł Brzęk
- Faculty of Biology, University of Białystok, Ciołkowskiego 1J, 15-245 Białystok, Poland
| | - Damien Roussel
- Univ Lyon, Université Claude Bernard Lyon 1, UMR 5023 LEHNA, CNRS, ENTPE, Villeurbanne, France
| | - Marek Konarzewski
- Faculty of Biology, University of Białystok, Ciołkowskiego 1J, 15-245 Białystok, Poland
| |
Collapse
|
3
|
Gursan A, Froeling M, Hendriks AD, Welting D, Kentgens APM, Klomp DWJ, Prompers JJ. Residual quadrupolar couplings observed in 7 Tesla deuterium MR spectra of skeletal muscle. Magn Reson Med 2021; 87:1165-1173. [PMID: 34657308 PMCID: PMC9297863 DOI: 10.1002/mrm.29053] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 09/21/2021] [Accepted: 09/30/2021] [Indexed: 12/21/2022]
Abstract
Purpose Deuterium metabolic imaging could potentially be used to investigate metabolism in skeletal muscle noninvasively. However, skeletal muscle is a tissue with a high degree of spatial organization. In this study, we investigated the effect of incomplete motional averaging on the naturally abundant deuterated water signal in 7 Tesla deuterium spectra of the lower leg muscles and the dependence on the angle between the muscle fibers and the main magnetic field B0, as determined by DTI. Methods Natural abundance deuterium MRSI measurements of the right lower leg muscles were performed at 7 Tesla. Three subjects were scanned in a supine position, with the right leg parallel with the B0 field. One subject was scanned twice; during the second scan, the subject was laying on his right side and the right knee was bent such that the angle between the right lower leg and B0 was approximately 45°. DTI was performed in the same subjects in the same positions at 3 Tesla to determine muscle fiber angles. Results We observed splittings in the natural abundance deuterated water signal. The size of the splittings varied between different muscles in the lower leg but were mostly similar among subjects for each muscle. The splittings depended on the orientation of the muscle fibers with respect to the main magnetic field B0. Conclusion Partial molecular alignment in skeletal muscle leads to residual deuteron quadrupolar couplings in deuterated water, the size of which depends on the angle between the muscle fibers and B0.
Collapse
Affiliation(s)
- Ayhan Gursan
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Martijn Froeling
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Arjan D Hendriks
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Dimitri Welting
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Arno P M Kentgens
- Magnetic Resonance Research Center, Institute for Molecules and Materials, Radboud University, Nijmegen, The Netherlands
| | - Dennis W J Klomp
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Jeanine J Prompers
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| |
Collapse
|
4
|
Galgani JE, Fernández-Verdejo R. Pathophysiological role of metabolic flexibility on metabolic health. Obes Rev 2021; 22:e13131. [PMID: 32815226 DOI: 10.1111/obr.13131] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 08/10/2020] [Accepted: 08/10/2020] [Indexed: 12/15/2022]
Abstract
Glucose, fatty acids, and amino acids among others are oxidized to generate adenosine triphosphate (ATP). These fuels are supplied from the environment (through food intake) and internal depots (through lipolysis, glycogenolysis, and proteolysis) at different rates throughout the day. Complex adaptive systems permit to accommodate fuel oxidation according to fuel availability. This capacity of a cell, tissue, or organism to adapt fuel oxidation to fuel availability is defined as metabolic flexibility (MetF). There are conditions, such as insulin resistance, diabetes, and obesity, in which MetF seems to be impaired. The observation that those conditions are accompanied by mitochondrial dysfunction has set the basis to propose a link between mitochondrial dysfunction, metabolic inflexibility, and metabolic health. We here highlight the evidence about the notion that MetF influences metabolic health.
Collapse
Affiliation(s)
- Jose E Galgani
- Department of Health Sciences, Nutrition and Dietetics Career, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile.,Department of Nutrition, Diabetes and Metabolism, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Rodrigo Fernández-Verdejo
- Department of Health Sciences, Nutrition and Dietetics Career, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| |
Collapse
|
5
|
Song JD, Alves TC, Befroy DE, Perry RJ, Mason GF, Zhang XM, Munk A, Zhang Y, Zhang D, Cline GW, Rothman DL, Petersen KF, Shulman GI. Dissociation of Muscle Insulin Resistance from Alterations in Mitochondrial Substrate Preference. Cell Metab 2020; 32:726-735.e5. [PMID: 33035493 PMCID: PMC8218871 DOI: 10.1016/j.cmet.2020.09.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 07/14/2020] [Accepted: 09/09/2020] [Indexed: 12/28/2022]
Abstract
Alterations in muscle mitochondrial substrate preference have been postulated to play a major role in the pathogenesis of muscle insulin resistance. In order to examine this hypothesis, we assessed the ratio of mitochondrial pyruvate oxidation (VPDH) to rates of mitochondrial citrate synthase flux (VCS) in muscle. Contrary to this hypothesis, we found that high-fat-diet (HFD)-fed insulin-resistant rats did not manifest altered muscle substrate preference (VPDH/VCS) in soleus or quadriceps muscles in the fasting state. Furthermore, hyperinsulinemic-euglycemic (HE) clamps increased VPDH/VCS in both muscles in normal and insulin-resistant rats. We then examined the muscle VPDH/VCS flux in insulin-sensitive and insulin-resistant humans and found similar relative rates of VPDH/VCS, following an overnight fast (∼20%), and similar increases in VPDH/VCS fluxes during a HE clamp. Altogether, these findings demonstrate that alterations in mitochondrial substrate preference are not an essential step in the pathogenesis of muscle insulin resistance.
Collapse
Affiliation(s)
- Joongyu D Song
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Tiago C Alves
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Douglas E Befroy
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA; Department of Radiology & Bioengineering, Yale School of Medicine, New Haven, CT, USA; PeakAnalysts, Benenden, Kent, UK
| | - Rachel J Perry
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA; Department of Cellular & Molecular Physiology, Yale School of Medicine, New Haven, CT, USA
| | - Graeme F Mason
- Department of Radiology & Bioengineering, Yale School of Medicine, New Haven, CT, USA; Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
| | - Xian-Man Zhang
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Alexander Munk
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Ye Zhang
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Dongyan Zhang
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Gary W Cline
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Douglas L Rothman
- Department of Radiology & Bioengineering, Yale School of Medicine, New Haven, CT, USA
| | - Kitt Falk Petersen
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA; Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark.
| | - Gerald I Shulman
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA; Department of Cellular & Molecular Physiology, Yale School of Medicine, New Haven, CT, USA.
| |
Collapse
|
6
|
Abstract
Temperature is a critical abiotic factor shaping the distribution and abundance of species, but the mechanisms that underpin organismal thermal limits remain poorly understood. One possible mechanism underlying these limits is the failure of mitochondrial processes, as mitochondria play a crucial role in animals as the primary site of ATP production. Conventional measures of mitochondrial performance suggest that these organelles can function at temperatures much higher than those that limit whole-organism function, suggesting that they are unlikely to set organismal thermal limits. However, this conclusion is challenged by recent data connecting sequence variation in mitochondrial genes to whole-organism thermal tolerance. Here, we review the current state of knowledge of mitochondrial responses to thermal extremes and ask whether they are consistent with a role for mitochondrial function in shaping whole-organism thermal limits. The available data are fragmentary, but it is possible to draw some conclusions. There is little evidence that failure of maximal mitochondrial oxidative capacity as assessed in vitro sets thermal limits, but there is some evidence to suggest that temperature effects on ATP synthetic capacity may be important. Several studies suggest that loss of mitochondrial coupling is associated with the thermal limits for organismal growth, although this needs to be rigorously tested. Most studies have utilized isolated mitochondrial preparations to assess the effects of temperature on these organelles, and there remain many untapped opportunities to address these questions using preparations that retain more of their biological context to better connect these subcellular processes with whole-organism thermal limits.
Collapse
Affiliation(s)
- Dillon J Chung
- National Heart Lung and Blood Institute, National Institutes of Health, 10 Center Drive, Bethesda, MD 20814, USA
| | - Patricia M Schulte
- Department of Zoology, University of British Columbia, 6270 University Blvd, Vancouver, British Columbia, Canada V6T 1Z4
| |
Collapse
|
7
|
Presby DM, Checkley LA, Jackman MR, Higgins JA, Jones KL, Giles ED, Houck JA, Webb PG, Steig AJ, Johnson GC, Rudolph MC, MacLean PS. Regular exercise potentiates energetically expensive hepatic de novo lipogenesis during early weight regain. Am J Physiol Regul Integr Comp Physiol 2019; 317:R684-R695. [PMID: 31553623 DOI: 10.1152/ajpregu.00074.2019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Exercise is a potent facilitator of long-term weight loss maintenance (WLM), whereby it decreases appetite and increases energy expenditure beyond the cost of the exercise bout. We have previously shown that exercise may amplify energy expenditure through energetically expensive nutrient deposition. Therefore, we investigated the effect of exercise on hepatic de novo lipogenesis (DNL) during WLM and relapse to obesity. Obese rats were calorically restricted with (EX) or without (SED) treadmill exercise (1 h/day, 6 days/wk, 15 m/min) to induce and maintain weight loss. After 6 wk of WLM, subsets of WLM-SED and WLM-EX rats were allowed ad libitum access to food for 1 day to promote relapse (REL). An energy gap-matched group of sedentary, relapsing rats (REL-GM) were provided a diet matched to the positive energy imbalance of the REL-EX rats. During relapse, exercise increased enrichment of hepatic DN-derived lipids and induced hepatic molecular adaptations favoring DNL compared with the gap-matched controls. In the liver, compared with both REL-SED and REL-GM rats, REL-EX rats had lower hepatic expression of genes required for cholesterol biosynthesis; greater hepatic expression of genes that mediate very low-density lipoprotein synthesis and secretion; and greater mRNA expression of Cyp27a1, which encodes an enzyme involved in the biosynthesis of bile acids. Altogether, these data provide compelling evidence that the liver has an active role in exercise-mediated potentiation of energy expenditure during early relapse.
Collapse
Affiliation(s)
- David M Presby
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - L Allyson Checkley
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Matthew R Jackman
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Janine A Higgins
- Department of Pediatrics, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Kenneth L Jones
- Department of Pediatrics, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Erin D Giles
- Department of Nutrition and Food Science at Texas A&M University, College Station, Texas
| | - Julie A Houck
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Patricia G Webb
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Amy J Steig
- Center for Human Nutrition at the University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Ginger C Johnson
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Michael C Rudolph
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Paul S MacLean
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado.,Department of Pathology, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado.,Center for Human Nutrition at the University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| |
Collapse
|
8
|
Stay Fit, Stay Young: Mitochondria in Movement: The Role of Exercise in the New Mitochondrial Paradigm. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:7058350. [PMID: 31320983 PMCID: PMC6607712 DOI: 10.1155/2019/7058350] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 04/23/2019] [Accepted: 05/08/2019] [Indexed: 12/29/2022]
Abstract
Skeletal muscles require the proper production and distribution of energy to sustain their work. To ensure this requirement is met, mitochondria form large networks within skeletal muscle cells, and during exercise, they can enhance their functions. In the present review, we discuss recent findings on exercise-induced mitochondrial adaptations. We emphasize the importance of mitochondrial biogenesis, morphological changes, and increases in respiratory supercomplex formation as mechanisms triggered by exercise that may increase the function of skeletal muscles. Finally, we highlight the possible effects of nutraceutical compounds on mitochondrial performance during exercise and outline the use of exercise as a therapeutic tool in noncommunicable disease prevention. The resulting picture shows that the modulation of mitochondrial activity by exercise is not only fundamental for physical performance but also a key point for whole-organism well-being.
Collapse
|
9
|
Is mitochondrial DNA profiling predictive for athletic performance? Mitochondrion 2019; 47:125-138. [PMID: 31228565 DOI: 10.1016/j.mito.2019.06.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Revised: 06/03/2019] [Accepted: 06/17/2019] [Indexed: 11/20/2022]
Abstract
Mitochondrial DNA encodes some proteins of the oxidative phosphorylation enzymatic complex, playing an important role in aerobic ATP production; therefore, it can contribute to the ability to respond to endurance exercise training. The accumulation of mitochondrial mutations and the migratory processes of populations have given a great contribution to the development of haplogroups with a different distribution in the world. Several studies have shown the important role of gene polymorphisms in aerobic performance. In this review, some mitochondrial haplogroups and multiple rare alleles were taken into consideration and could be linked to the athlete's physical performance of different ethnic groups.
Collapse
|
10
|
Nonaka K, Ozaki Y, Ito K, Sakita M, Une S, Akiyama J. Endurance exercise increases the protein levels of PGC-1α and respiratory chain complexes in mouse skeletal muscle during atorvastatin administration. J Physiol Sci 2019; 69:327-333. [PMID: 30536041 PMCID: PMC10717863 DOI: 10.1007/s12576-018-0649-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 11/27/2018] [Indexed: 11/29/2022]
Abstract
Statins and exercise reduce cardiovascular disease incidence. We investigated whether endurance exercise in mice induces mitochondrial adaptation in skeletal muscle and muscle injury during administration of atorvastatin, a member of the statin medication class. Male C57BL mice were assigned to one of three groups: control (Con), statin (Statin), or statin and exercise (Statin + Ex). Atorvastatin was administered, and exercise performed on a treadmill for 8 weeks. The levels of mitochondria-associated proteins, PGC-1α, and respiratory chain complex, (COX) I-V, in the quadriceps femoris, and serum creatine kinase, a muscle injury marker, were measured. PGC-1α and COX I-V were upregulated in the Statin + Ex group compared to those in the Statin and Con groups; serum creatine kinase levels were similar. Endurance training in mice induced mitochondrial adaptation in skeletal muscle without causing muscle injury, during atorvastatin administration.
Collapse
Affiliation(s)
- Koji Nonaka
- Department of Physical Therapy, Faculty of Health Sciences, Kyoto Tachibana University, 34 Oyakeyamada-cho, Yamashina-ku, Kyoto, Kyoto, 607-8175, Japan.
| | - Yutaka Ozaki
- Department of Rehabilitation, Kansai Electric Power Hospital, Osaka, Japan
| | - Kenichi Ito
- Faculty of Health Sciences, Naragakuen University, Nara, Japan
| | - Masahiro Sakita
- Department of Physical Therapy, Faculty of Health Sciences, Kyoto Tachibana University, 34 Oyakeyamada-cho, Yamashina-ku, Kyoto, Kyoto, 607-8175, Japan
| | - Satsuki Une
- Faculty of Education, Kagawa University, Takamatsu, Kagawa, Japan
| | - Junichi Akiyama
- Department of Physical Therapy, School of Health Care and Social Welfare, Kibi International University, Takahashi, Okayama, Japan
| |
Collapse
|
11
|
Koh AS, Gao F, Tan RS, Zhong L, Leng S, Zhao X, Fridianto KT, Ching J, Lee SY, Keng BMH, Yeo TJ, Tan SY, Tan HC, Lim CT, Koh WP, Kovalik JP. Metabolomic correlates of aerobic capacity among elderly adults. Clin Cardiol 2018; 41:1300-1307. [PMID: 30350416 DOI: 10.1002/clc.23016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 06/22/2018] [Accepted: 06/24/2018] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Aerobic capacity is a powerful predictor of cardiovascular disease and all-cause mortality, and it declines with advancing age. HYPOTHESIS Since physical activity alters body metabolism, metabolism markers will likely differ between subjects with high vs low aerobic capacities. METHODS Community-based participants without physician-diagnosed heart disease, stroke or cancer underwent same-day multimodal assessment of cardiovascular function (by echocardiography and magnetic resonance feature tracking of left atrium) and aerobic capacity by peak oxygen uptake (VO2 ) metrics. Associations between VO2 and cardiovascular and metabolomics profiles were studied in adjusted models including standard covariates. RESULTS We studied 141 participants, of whom 82 (58.2%) had low VO2 , while 59 (41.8%) had high VO2 . Compared to participants with high VO2 , participants with low VO2 had more adverse cardiovascular parameters, such as lower ratio of peak velocity flow in early diastole to peak velocity flow in late diastole by atrial contraction of >0.8 (76% vs 35%, adjusted odd ratio [OR] = 4.1, 95% confidence interval [CI] [1.7-9.5], P = 0.001) and lower left atrial conduit strain (11.3 ± 4.0 vs 15.6 ± 6.1%, adjusted OR = 1.1, 95% CI [1.002-1.3], P = 0.045). High VO2 was associated with lower accumulation of wide-spectrum acyl-carnitines (OR = 0.6, 95% CI [0.4-0.9], P = 0.013), alanine (OR = 0.1, 95% CI [0.01-0.9], P = 0.044) and glutamine /glutamate (OR = 0.1, 95% CI [0.01-0.5], P = 0.007), compared to low VO2. CONCLUSION: Elderly adults with low VO2 have adverse cardiovascular and metabolic parameters compared to their counterparts with high VO2 . Combined cardiac and metabolomics phenotyping may be a promising tool to provide insights into physiological states, useful for tracking future interventions related to physical activity among community cohorts.
Collapse
Affiliation(s)
- Angela S Koh
- Department of Cardiology, National Heart Centre Singapore, Duke-NUS Medical School, Singapore
| | - Fei Gao
- Department of Cardiology, National Heart Centre Singapore, Singapore, Centre for Quantitative Medicine, Duke-NUS Medical School, Singapore
| | - Ru S Tan
- Department of Cardiology, National Heart Centre Singapore, Duke-NUS Medical School, Singapore
| | - Liang Zhong
- Department of Cardiology, National Heart Centre Singapore, Duke-NUS Medical School, Singapore
| | - Shuang Leng
- Department of Cardiology, National Heart Centre, Singapore
| | - Xiaodan Zhao
- Department of Cardiology, National Heart Centre, Singapore
| | - Kevin T Fridianto
- Cardiovascular and Metabolic Diseases Programme, Duke-NUS Medical School, Singapore
| | - Jianhong Ching
- Cardiovascular and Metabolic Diseases Programme, Duke-NUS Medical School, Singapore
| | - Si Y Lee
- Department of Cardiology, National Heart Centre, Singapore
| | - Bryan M H Keng
- Department of Cardiology, National Heart Centre, Singapore
| | - Tee Joo Yeo
- Department of Cardiology, National University Heart Centre Singapore
| | - Shu Y Tan
- Department of Family Medicine and Continuing Care, General Hospital, Singapore
| | - Hong C Tan
- Department of Endocrinology, General Hospital, Singapore
| | - Chin T Lim
- Department of Orthopaedic Surgery, National University Hospital, Singapore
| | - Woon-Puay Koh
- Health Services and Systems Research, Duke-NUS Medical School, Singapore
| | - Jean-Paul Kovalik
- Cardiovascular and Metabolic Diseases Programme, Duke-NUS Medical School, Singapore.,Department of Endocrinology, General Hospital, Singapore
| |
Collapse
|
12
|
Hart CR, Lanza IR. Mitochondrial ADP Sensitivity and Transport: New Insights Into Diet-Induced Mitochondrial Impairments. Diabetes 2018; 67:2152-2153. [PMID: 30348821 DOI: 10.2337/dbi18-0030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Corey R Hart
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic College of Medicine and Science, Rochester, MN
| | - Ian R Lanza
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic College of Medicine and Science, Rochester, MN
| |
Collapse
|
13
|
Dyar KA, Hubert MJ, Mir AA, Ciciliot S, Lutter D, Greulich F, Quagliarini F, Kleinert M, Fischer K, Eichmann TO, Wright LE, Peña Paz MI, Casarin A, Pertegato V, Romanello V, Albiero M, Mazzucco S, Rizzuto R, Salviati L, Biolo G, Blaauw B, Schiaffino S, Uhlenhaut NH. Transcriptional programming of lipid and amino acid metabolism by the skeletal muscle circadian clock. PLoS Biol 2018; 16:e2005886. [PMID: 30096135 PMCID: PMC6105032 DOI: 10.1371/journal.pbio.2005886] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 08/22/2018] [Accepted: 07/27/2018] [Indexed: 12/30/2022] Open
Abstract
Circadian clocks are fundamental physiological regulators of energy homeostasis, but direct transcriptional targets of the muscle clock machinery are unknown. To understand how the muscle clock directs rhythmic metabolism, we determined genome-wide binding of the master clock regulators brain and muscle ARNT-like protein 1 (BMAL1) and REV-ERBα in murine muscles. Integrating occupancy with 24-hr gene expression and metabolomics after muscle-specific loss of BMAL1 and REV-ERBα, here we unravel novel molecular mechanisms connecting muscle clock function to daily cycles of lipid and protein metabolism. Validating BMAL1 and REV-ERBα targets using luciferase assays and in vivo rescue, we demonstrate how a major role of the muscle clock is to promote diurnal cycles of neutral lipid storage while coordinately inhibiting lipid and protein catabolism prior to awakening. This occurs by BMAL1-dependent activation of Dgat2 and REV-ERBα-dependent repression of major targets involved in lipid metabolism and protein turnover (MuRF-1, Atrogin-1). Accordingly, muscle-specific loss of BMAL1 is associated with metabolic inefficiency, impaired muscle triglyceride biosynthesis, and accumulation of bioactive lipids and amino acids. Taken together, our data provide a comprehensive overview of how genomic binding of BMAL1 and REV-ERBα is related to temporal changes in gene expression and metabolite fluctuations.
Collapse
Affiliation(s)
- Kenneth Allen Dyar
- Helmholtz Diabetes Center (HMGU) and German Center for Diabetes Research (DZD), Institute for Diabetes and Obesity (IDO), Munich, Germany
- Venetian Institute of Molecular Medicine (VIMM), Padova, Italy
| | - Michaël Jean Hubert
- Helmholtz Diabetes Center (HMGU) and German Center for Diabetes Research (DZD), Institute for Diabetes and Obesity (IDO), Munich, Germany
| | - Ashfaq Ali Mir
- Helmholtz Diabetes Center (HMGU) and German Center for Diabetes Research (DZD), Institute for Diabetes and Obesity (IDO), Munich, Germany
| | | | - Dominik Lutter
- Helmholtz Diabetes Center (HMGU) and German Center for Diabetes Research (DZD), Institute for Diabetes and Obesity (IDO), Munich, Germany
| | - Franziska Greulich
- Helmholtz Diabetes Center (HMGU) and German Center for Diabetes Research (DZD), Institute for Diabetes and Obesity (IDO), Munich, Germany
| | - Fabiana Quagliarini
- Helmholtz Diabetes Center (HMGU) and German Center for Diabetes Research (DZD), Institute for Diabetes and Obesity (IDO), Munich, Germany
| | - Maximilian Kleinert
- Helmholtz Diabetes Center (HMGU) and German Center for Diabetes Research (DZD), Institute for Diabetes and Obesity (IDO), Munich, Germany
| | - Katrin Fischer
- Helmholtz Diabetes Center (HMGU) and German Center for Diabetes Research (DZD), Institute for Diabetes and Obesity (IDO), Munich, Germany
| | | | | | | | - Alberto Casarin
- Clinical Genetics Unit, Department of Woman and Child Health, University of Padova, and IRP Città della Speranza, Padova, Italy
| | - Vanessa Pertegato
- Clinical Genetics Unit, Department of Woman and Child Health, University of Padova, and IRP Città della Speranza, Padova, Italy
| | | | - Mattia Albiero
- Venetian Institute of Molecular Medicine (VIMM), Padova, Italy
| | - Sara Mazzucco
- Clinica Medica, Department of Medical Sciences, University of Trieste, Trieste, Italy
| | - Rosario Rizzuto
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Leonardo Salviati
- Clinical Genetics Unit, Department of Woman and Child Health, University of Padova, and IRP Città della Speranza, Padova, Italy
| | - Gianni Biolo
- Clinica Medica, Department of Medical Sciences, University of Trieste, Trieste, Italy
| | - Bert Blaauw
- Venetian Institute of Molecular Medicine (VIMM), Padova, Italy
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | | | - N. Henriette Uhlenhaut
- Helmholtz Diabetes Center (HMGU) and German Center for Diabetes Research (DZD), Institute for Diabetes and Obesity (IDO), Munich, Germany
- Gene Center, Ludwig-Maximilians-Universitaet (LMU), Munich, Germany
| |
Collapse
|
14
|
Partial involvement of Nrf2 in skeletal muscle mitohormesis as an adaptive response to mitochondrial uncoupling. Sci Rep 2018; 8:2446. [PMID: 29402993 PMCID: PMC5799251 DOI: 10.1038/s41598-018-20901-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Accepted: 01/26/2018] [Indexed: 12/13/2022] Open
Abstract
Mitochondrial dysfunction is usually associated with various metabolic disorders and ageing. However, salutary effects in response to mild mitochondrial perturbations have been reported in multiple organisms, whereas molecular regulators of cell-autonomous stress responses remain elusive. We addressed this question by asking whether the nuclear factor erythroid-derived-like 2 (Nrf2), a transcription factor and master regulator of cellular redox status is involved in adaptive physiological responses including muscle mitohormesis. Using a transgenic mouse model with skeletal muscle-specific mitochondrial uncoupling and oxidative phosphorylation (OXPHOS) inefficiency (UCP1-transgenic, TG) we show that additional genetic ablation of Nrf2 abolishes an adaptive muscle NAD(P)H quinone dehydrogenase 1 (NQO1) and catalase induction. Deficiency of Nrf2 also leads to decreased mitochondrial respiratory performance although muscle functional integrity, fiber-type profile and mitochondrial biogenesis were not significantly altered. Importantly, Nrf2 ablation did not abolish the induction of key genes and proteins of muscle integrated stress response including the serine, one-carbon cycle, and glycine synthesis (SOG) pathway in TG mice while further increasing glutathione peroxidase (GPX) activity linked to increased GPX1 protein levels. Conclusively, our results tune down the functions controlled by Nrf2 in muscle mitohormesis and oxidative stress defense during mitochondrial OXPHOS inefficiency.
Collapse
|
15
|
Abstract
Brown fat is emerging as an interesting and promising target for therapeutic intervention in obesity and metabolic disease. Activation of brown fat in humans is associated with marked improvement in metabolic parameters such as levels of free fatty acids and insulin sensitivity. Skeletal muscle is another important organ for thermogenesis, with the capacity to induce energy-consuming futile cycles. In this Review, we focus on how these two major thermogenic organs - brown fat and muscle - act and cooperate to maintain normal body temperature. Moreover, in the light of disease-relevant mechanisms, we explore the molecular pathways that regulate thermogenesis in brown fat and muscle. Brown adipocytes possess a unique cellular mechanism to convert chemical energy into heat: uncoupling protein 1 (UCP1), which can short-circuit the mitochondrial proton gradient. However, recent research demonstrates the existence of several other energy-expending 'futile' cycles in both adipocytes and muscle, such as creatine and calcium cycling. These mechanisms can complement or even substitute for UCP1-mediated thermogenesis. Moreover, they expand our view of cold-induced thermogenesis from a special feature of brown adipocytes to a more general physiological principle. Finally, we discuss how thermogenic mechanisms can be exploited to expend energy and hence offer new therapeutic opportunities.
Collapse
Affiliation(s)
- Matthias J Betz
- Department of Endocrinology, Diabetes and Metabolism, University Hospital Basel, Petersgraben 4, CH-4031 Basel, Switzerland
| | - Sven Enerbäck
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, The Sahlgrenska Academy, University of Gothenburg, Medicinaregatan 9A, SE-405 30 Gothenburg, Sweden
| |
Collapse
|
16
|
Musci RV, Hamilton KL, Miller BF. Targeting mitochondrial function and proteostasis to mitigate dynapenia. Eur J Appl Physiol 2018; 118:1-9. [PMID: 28986697 PMCID: PMC5756099 DOI: 10.1007/s00421-017-3730-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 09/30/2017] [Indexed: 12/25/2022]
Abstract
Traditionally, interventions to treat skeletal muscle aging have largely targeted sarcopenia-the age-related loss of skeletal muscle mass. Dynapenia refers to the age-related loss in skeletal muscle function due to factors outside of muscle mass, which helps to inform treatment strategies for aging skeletal muscle. There is evidence that mechanisms to maintain protein homeostasis and proteostasis, deteriorate with age. One key mechanism to maintain proteostasis is protein turnover, which is an energetically costly process. When there is a mismatch between cellular energy demands and energy provision, inelastic processes related to metabolism are maintained, but there is competition for the remaining energy between the elastic processes of somatic maintenance and growth. With aging, mitochondrial dysfunction reduces ATP generation capacity, constraining the instantaneous supply of energy, thus compromising growth and somatic maintenance processes. Further, with age the need for somatic maintenance increases because of the accumulation of protein damage. In this review, we highlight the significant role mitochondria have in maintaining skeletal muscle proteostasis through increased energy provision, protein turnover, and substrate flux. In addition, we provide evidence that improving mitochondrial function could promote a cellular environment that is conducive to somatic maintenance, and consequently for mitigating dynapenia. Finally, we highlight interventions, such as aerobic exercise, that could be used to improve mitochondrial function and improve outcomes related to dynapenia.
Collapse
Affiliation(s)
- Robert V Musci
- Translational Research on Aging and Chronic Disease Laboratory, Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, 80523-1582, USA
| | - Karyn L Hamilton
- Translational Research on Aging and Chronic Disease Laboratory, Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, 80523-1582, USA
| | - Benjamin F Miller
- Translational Research on Aging and Chronic Disease Laboratory, Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, 80523-1582, USA.
| |
Collapse
|
17
|
Dai Z, Shestov AA, Lai L, Locasale JW. A Flux Balance of Glucose Metabolism Clarifies the Requirements of the Warburg Effect. Biophys J 2017; 111:1088-100. [PMID: 27602736 DOI: 10.1016/j.bpj.2016.07.028] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 07/20/2016] [Accepted: 07/22/2016] [Indexed: 12/19/2022] Open
Abstract
The Warburg effect, or aerobic glycolysis, is marked by the increased metabolism of glucose to lactate in the presence of oxygen. Despite its widespread prevalence in physiology and cancer biology, the causes and consequences remain incompletely understood. Here, we show that a simple balance of interacting fluxes in glycolysis creates constraints that impose the necessary conditions for glycolytic flux to generate lactate as opposed to entering into the mitochondria. These conditions are determined by cellular redox and energy demands. By analyzing the constraints and sampling the feasible region of the model, we further study how cell proliferation rate and mitochondria-associated NADH oxidizing and ATP producing fluxes are interlinked. Together this analysis illustrates the simplicity of the origins of the Warburg effect by identifying the flux distributions that are necessary for its instantiation.
Collapse
Affiliation(s)
- Ziwei Dai
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Duke Molecular Physiology Institute, Duke Cancer Institute, Durham, North Carolina; Center for Quantitative Biology, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Alexander A Shestov
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Luhua Lai
- Center for Quantitative Biology, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Jason W Locasale
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Duke Molecular Physiology Institute, Duke Cancer Institute, Durham, North Carolina.
| |
Collapse
|
18
|
Chen Y, Hill HZ, Lange G, Falvo MJ. Salivary Mitochondrial DNA Copy Number Is Associated With Exercise Ventilatory Efficiency. J Strength Cond Res 2017. [PMID: 28640773 DOI: 10.1519/jsc.0000000000001932] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Chen, Y, Hill, HZ, Lange, G, and Falvo, MJ. Salivary mitochondrial DNA copy number is associated with exercise ventilatory efficiency. J Strength Cond Res 31(7): 2000-2004, 2017-Mitochondrial DNA copy number (mtDNAcn) is an index of mitochondrial content and is responsive to changes in exercise training volume. Therefore, assessment of mtDNAcn may help to optimize exercise prescription and aid in athlete monitoring. Although previous work has assessed mtDNAcn derived from skeletal muscle and blood using invasive approaches, no study has examined salivary mtDNAcn and its relationship with sport performance. Fifteen adults (32.2 ± 7.1 years) volunteered to participate in this study. Each participant provided a saliva sample for the analysis of mtDNAcn via real-time polymerase reaction. In addition, participants completed an exercise challenge test to assess oxygen consumption relative to body weight (V[Combining Dot Above]O2·kg) and ventilatory efficiency (VE/V[Combining Dot Above]CO2). Using multiple linear regression, we examined the association of V[Combining Dot Above]O2·kg and VE/V[Combining Dot Above]CO2 with salivary mtDNAcn, adjusting for self-reported physical activity (min·wk). Greater mtDNAcn was associated with lower VE/V[Combining Dot Above]CO2 (p < 0.01) and higher V[Combining Dot Above]O2·kg (p < 0.05). In our model adjusted for physical activity, greater mtDNAcn remained associated with lower VE/V[Combining Dot Above]CO2 (β = -0.186; 95% confidence interval [CI], -0.348 to -0.025; p < 0.05), but not with V[Combining Dot Above]O2·kg (β = -0.022; 95% CI, -0.113 to 0.063). Our findings suggest that salivary mtDNAcn is associated with ventilatory efficiency, which may reflect enhanced exercise efficiency as a consequence of greater total mitochondrial content. As saliva collection is noninvasive, stable at room temperature, and less costly in comparison to skeletal muscle and blood, future studies may consider using saliva for the evaluation of mitochondrial content for the purposes of monitoring exercise training as well as optimizing exercise prescription.
Collapse
Affiliation(s)
- Yang Chen
- 1VA NJ Health Care System, War Related Illness and Injury Study Center, East Orange, New Jersey;2Rutgers Biomedical and Health Sciences, Department of Pharmacology, Physiology and Neuroscience, Newark, New Jersey;3Rutgers Biomedical and Health Sciences, Department of Radiology, New Jersey Medical School, Newark, New Jersey;4Rutgers Biomedical and Health Sciences, Department of Physical Medicine and Rehabilitation, Newark, New Jersey; and5Pain and Fatigue Study Center, Beth Israel Medical Center and Albert Einstein Medical Center, New York, New York
| | | | | | | |
Collapse
|
19
|
Clark A, Mach N. The Crosstalk between the Gut Microbiota and Mitochondria during Exercise. Front Physiol 2017; 8:319. [PMID: 28579962 PMCID: PMC5437217 DOI: 10.3389/fphys.2017.00319] [Citation(s) in RCA: 200] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 05/03/2017] [Indexed: 12/16/2022] Open
Abstract
Many physiological changes occur in response to endurance exercise in order to adapt to the increasing energy needs, mitochondria biogenesis, increased reactive oxygen species (ROS) production and acute inflammatory responses. Mitochondria are organelles within each cell that are crucial for ATP production and are also a major producer of ROS and reactive nitrogen species during intense exercise. Recent evidence shows there is a bidirectional interaction between mitochondria and microbiota. The gut microbiota have been shown to regulate key transcriptional co-activators, transcription factors and enzymes involved in mitochondrial biogenesis such as PGC-1α, SIRT1, and AMPK genes. Furthermore, the gut microbiota and its metabolites, such as short chain fatty acids and secondary bile acids, also contribute to host energy production, ROS modulation and inflammation in the gut by attenuating TNFα- mediated immune responses and inflammasomes such as NLRP3. On the other hand, mitochondria, particularly mitochondrial ROS production, have a crucial role in regulating the gut microbiota via modulating intestinal barrier function and mucosal immune responses. Recently, it has also been shown that genetic variants within the mitochondrial genome, could affect mitochondrial function and therefore the intestinal microbiota composition and activity. Diet is also known to dramatically modulate the composition of the gut microbiota. Therefore, studies targeting the gut microbiota can be useful for managing mitochondrial related ROS production, pro-inflammatory signals and metabolic limits in endurance athletes.
Collapse
Affiliation(s)
- Allison Clark
- Health Science Department, Open University of CataloniaBarcelona, Spain
| | - Núria Mach
- Health Science Department, Open University of CataloniaBarcelona, Spain.,UMR 1313, INRA, AgroParisTech, Université Paris-SaclayJouy-en-Josas, France
| |
Collapse
|
20
|
Layec G, Bringard A, Le Fur Y, Micallef JP, Vilmen C, Perrey S, Cozzone PJ, Bendahan D. Mitochondrial Coupling and Contractile Efficiency in Humans with High and Low V˙O2peaks. Med Sci Sports Exerc 2017; 48:811-21. [PMID: 26694849 DOI: 10.1249/mss.0000000000000858] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
INTRODUCTION Endurance training elicits tremendous adaptations of the mitochondrial energetic capacity. Yet, the effects of training or physical fitness on mitochondrial efficiency during exercise are still unclear. Accordingly, the purpose of the present study was to examine in vivo the differences in mitochondrial efficiency and ATP cost of contraction during exercise in two groups of adults differing in their aerobic capacity. METHOD We simultaneously assessed the ATP synthesis and O2 fluxes with P-magnetic resonance spectroscopy and pulmonary gas exchange measurements in seven endurance-trained (ET, V˙O2max: 67 ± 8 mL·min⁻¹·kg⁻¹) and seven recreationally active (RA, V˙O2max: 43 ± 7 mL·min⁻¹·kg⁻¹) subjects during 6 min of dynamic moderate-intensity knee extension. RESULTS The ATP cost of dynamic contraction was not significantly different between ET and RA (P > 0.05). Similarly, end-exercise O2 consumption was not significantly different between groups (ET: 848 ± 155 mL·min⁻¹ and RA: 760 ± 131 mL·min⁻¹, P > 0.05). During the recovery period, the PCr offset time constant was significantly faster in ET compared with RA (ET: 32 ± 8 s and RA: 43 ± 10 s, P < 0.05), thus indicating an increased mitochondrial capacity for ATP synthesis in the quadriceps of ET. In contrast, the estimated mitochondrial efficiency during exercise was not significantly different (P/O, ET: 2.0 ± 1.0 and RA: 1.8 ± 0.4, P > 0.05). Consequently, the higher mitochondrial capacity for ATP synthesis in ET likely originated from an elevated mitochondrial volume density, mitochondria-specific respiratory capacity, and/or slower postexercise inactivation of oxidative phosphorylation by the parallel activation mechanism. CONCLUSION Together, these findings reveal that 1) mitochondrial and contractile efficiencies are unaltered by several years of endurance training in young adults, and 2) the training-induced improvement in mitochondrial energetic capacity appears to be independent from changes in mitochondrial coupling.
Collapse
Affiliation(s)
- Gwenael Layec
- 1Aix-Marseille University, Centre National de la Recherche Scientifique, Center for Magnetic Resonance in Biology and Medicine, Unite Mixte de Recherche 7339, Marseille, FRANCE; 2Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT; 3Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT; 4Department of Anesthesiology, Pharmacology and Intensive Care and Department of Fundamental Neurosciences, University of Geneva, SWITZERLAND; 5Motricity Efficiency and Deficiency, EA 2991, Faculty of Sport Science, Unite de Formation et de Recherche en Sciences et Techniques des Activites Physiques et Sportives, Montpellier, FRANCE; 6INSERM ADR 08, Montpellier, FRANCE
| | | | | | | | | | | | | | | |
Collapse
|
21
|
Hesselink MKC, Schrauwen-Hinderling V, Schrauwen P. Skeletal muscle mitochondria as a target to prevent or treat type 2 diabetes mellitus. Nat Rev Endocrinol 2016; 12:633-645. [PMID: 27448057 DOI: 10.1038/nrendo.2016.104] [Citation(s) in RCA: 175] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Low levels of physical activity and the presence of obesity are associated with mitochondrial dysfunction. In addition, mitochondrial dysfunction has been associated with the development of insulin resistance and type 2 diabetes mellitus (T2DM). Although the evidence for a causal relationship between mitochondrial function and insulin resistance is still weak, emerging evidence indicates that boosting mitochondrial function might be beneficial to patient health. Exercise training is probably the most recognized promoter of mitochondrial function and insulin sensitivity and hence is still regarded as the best strategy to prevent and treat T2DM. Animal data, however, have revealed several new insights into the regulation of mitochondrial metabolism, and novel targets for interventions to boost mitochondrial function have emerged. Importantly, many of these targets seem to be regulated by factors such as nutrition, ambient temperature and circadian rhythms, which provides a basis for nonpharmacological strategies to prevent or treat T2DM in humans. Here, we will review the current evidence that mitochondrial function can be targeted therapeutically to improve insulin sensitivity and to prevent T2DM, focusing mainly on human intervention studies.
Collapse
Affiliation(s)
- Matthijs K C Hesselink
- Department of Human Biology and Human Movement Sciences, Maastricht University Medical Center, Universiteitsingel 50, 6229 ER, Maastricht, Netherlands
- NUTRIM, School for Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Universiteitsingel 50, 6229 ER, Maastricht, Netherlands
| | - Vera Schrauwen-Hinderling
- Department of Human Biology and Human Movement Sciences, Maastricht University Medical Center, Universiteitsingel 50, 6229 ER, Maastricht, Netherlands
- NUTRIM, School for Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Universiteitsingel 50, 6229 ER, Maastricht, Netherlands
- Department of Radiology, Maastricht University Medical Center, P. Debyelaan 25, 6229 HX, Maastricht, Netherlands
| | - Patrick Schrauwen
- Department of Human Biology and Human Movement Sciences, Maastricht University Medical Center, Universiteitsingel 50, 6229 ER, Maastricht, Netherlands
- NUTRIM, School for Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Universiteitsingel 50, 6229 ER, Maastricht, Netherlands
| |
Collapse
|
22
|
Schrauwen P, van Marken Lichtenbelt WD. Combatting type 2 diabetes by turning up the heat. Diabetologia 2016; 59:2269-2279. [PMID: 27591854 PMCID: PMC5506100 DOI: 10.1007/s00125-016-4068-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 06/22/2016] [Indexed: 12/21/2022]
Abstract
In our westernised society, the level of physical activity is low. Interventions that increase energy expenditure are generally associated with an improvement in metabolic health. Exercise and exercise training increase energy metabolism and are considered to be among the best strategies for prevention of type 2 diabetes mellitus. More recently, cold exposure has been suggested to have a therapeutic value in type 2 diabetes. At a cellular level, there is evidence that increasing the turnover of cellular substrates such as fatty acids is associated with preventive effects against lipid-induced insulin resistance. Cellular energy sensors may underlie the effects linking energy turnover with metabolic health effects. Here we review data supporting the hypothesis that increasing energy and substrate turnover has beneficial effects on insulin sensitivity and should be considered a target for the prevention and treatment of type 2 diabetes.
Collapse
Affiliation(s)
- Patrick Schrauwen
- Department of Human Biology and Human Movement Sciences, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, P.O. BOX 616, 6200MD, Maastricht, the Netherlands.
| | - Wouter D van Marken Lichtenbelt
- Department of Human Biology and Human Movement Sciences, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, P.O. BOX 616, 6200MD, Maastricht, the Netherlands
| |
Collapse
|
23
|
Conley KE. Mitochondria to motion: optimizing oxidative phosphorylation to improve exercise performance. ACTA ACUST UNITED AC 2016; 219:243-9. [PMID: 26792336 DOI: 10.1242/jeb.126623] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Mitochondria oxidize substrates to generate the ATP that fuels muscle contraction and locomotion. This review focuses on three steps in oxidative phosphorylation that have independent roles in setting the overall mitochondrial ATP flux and thereby have direct impact on locomotion. The first is the electron transport chain, which sets the pace for oxidation. New studies indicate that the electron transport chain capacity per mitochondria declines with age and disease, but can be revived by both acute and chronic treatments. The resulting higher ATP production is reflected in improved muscle power output and locomotory performance. The second step is the coupling of ATP supply from O2 uptake (mitochondrial coupling efficiency). Treatments that elevate mitochondrial coupling raise both exercise efficiency and the capacity for sustained exercise in both young and old muscle. The final step is ATP synthesis itself, which is under dynamic control at multiple sites to provide the 50-fold range of ATP flux between resting muscle and exercise at the mitochondrial capacity. Thus, malleability at sites in these subsystems of oxidative phosphorylation has an impact on ATP flux, with direct effects on exercise performance. Interventions are emerging that target these three independent subsystems to provide many paths to improve ATP flux and elevate the muscle performance lost to inactivity, age or disease.
Collapse
Affiliation(s)
- Kevin E Conley
- Departments of Radiology, Physiology & Biophysics, and Bioengineering, University of Washington Medical Center, Seattle, WA 98195, USA
| |
Collapse
|
24
|
Assessment of Hepatic Mitochondrial Oxidation and Pyruvate Cycling in NAFLD by (13)C Magnetic Resonance Spectroscopy. Cell Metab 2016; 24:167-71. [PMID: 27411016 PMCID: PMC4946568 DOI: 10.1016/j.cmet.2016.06.005] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2016] [Revised: 05/07/2016] [Accepted: 06/08/2016] [Indexed: 01/02/2023]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, and there is great interest in understanding the potential role of alterations in mitochondrial metabolism in its pathogenesis. To address this question, we assessed rates of hepatic mitochondrial oxidation in subjects with and without NAFLD by monitoring the rate of (13)C labeling in hepatic [5-(13)C]glutamate and [1-(13)C]glutamate by (13)C MRS during an infusion of [1-(13)C]acetate. We found that rates of hepatic mitochondrial oxidation were similar between NAFLD and control subjects. We also assessed rates of hepatic pyruvate cycling during an infusion of [3-(13)C]lactate by monitoring the (13)C label in hepatic [2-(13)C]alanine and [2-(13)C]glutamate and found that this flux was also similar between groups and more than 10-fold lower than previously reported. Contrary to previous studies, we show that hepatic mitochondrial oxidation and pyruvate cycling are not altered in NAFLD and do not account for the hepatic fat accumulation.
Collapse
|
25
|
Sparks LM, Gemmink A, Phielix E, Bosma M, Schaart G, Moonen-Kornips E, Jörgensen JA, Nascimento EBM, Hesselink MKC, Schrauwen P, Hoeks J. ANT1-mediated fatty acid-induced uncoupling as a target for improving myocellular insulin sensitivity. Diabetologia 2016; 59:1030-9. [PMID: 26886198 PMCID: PMC4826430 DOI: 10.1007/s00125-016-3885-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 01/15/2016] [Indexed: 12/29/2022]
Abstract
AIMS/HYPOTHESIS Dissipating energy via mitochondrial uncoupling has been suggested to contribute to enhanced insulin sensitivity. We hypothesised that skeletal muscle mitochondria of endurance-trained athletes have increased sensitivity for fatty acid (FA)-induced uncoupling, which is driven by the mitochondrial protein adenine nucleotide translocase 1 (ANT1). METHODS Capacity for FA-induced uncoupling was measured in endurance-trained male athletes (T) and sedentary young men (UT) in an observational study and also in isolated skeletal muscle mitochondria from Zucker diabetic fatty (ZDF) rats and C2C12 myotubes following small interfering RNA (siRNA)-mediated gene silencing of ANT1. Thus, fuelled by glutamate/succinate (fibres) or pyruvate (mitochondria and myotubes) and in the presence of oligomycin to block ATP synthesis, increasing levels of oleate (fibres) or palmitate (mitochondria and myotubes) were automatically titrated while respiration was monitored. Insulin sensitivity was measured by hyperinsulinaemic-euglycaemic clamp in humans and via insulin-stimulated glucose uptake in myotubes. RESULTS Skeletal muscle from the T group displayed increased sensitivity to FA-induced uncoupling (p = 0.011) compared with muscle from the UT group, and this was associated with elevated insulin sensitivity (p = 0.034). ANT1 expression was increased in T (p = 0.013). Mitochondria from ZDF rats displayed decreased sensitivity for FA-induced uncoupling (p = 0.008). This difference disappeared in the presence of the adenine nucleotide translocator inhibitor carboxyatractyloside. Partial knockdown of ANT1 in C2C12 myotubes decreased sensitivity to the FA-induced uncoupling (p = 0.008) and insulin-stimulated glucose uptake (p = 0.025) compared with controls. CONCLUSIONS/INTERPRETATION Increased sensitivity to FA-induced uncoupling is associated with enhanced insulin sensitivity and is affected by ANT1 activity in skeletal muscle. FA-induced mitochondrial uncoupling may help to preserve insulin sensitivity in the face of a high supply of FAs. TRIAL REGISTRATION www.trialregister.nl NTR2002.
Collapse
Affiliation(s)
- Lauren M Sparks
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, P. O. Box 616, 6200MD, Maastricht, the Netherlands
- Translational Research Institute for Metabolism and Diabetes, Florida Hospital, Orlando, FL, USA
| | - Anne Gemmink
- Department of Human Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, Maastricht, the Netherlands
| | - Esther Phielix
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, P. O. Box 616, 6200MD, Maastricht, the Netherlands
| | - Madeleen Bosma
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, P. O. Box 616, 6200MD, Maastricht, the Netherlands
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Gert Schaart
- Department of Human Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, Maastricht, the Netherlands
| | - Esther Moonen-Kornips
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, P. O. Box 616, 6200MD, Maastricht, the Netherlands
| | - Johanna A Jörgensen
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, P. O. Box 616, 6200MD, Maastricht, the Netherlands
| | - Emmani B M Nascimento
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, P. O. Box 616, 6200MD, Maastricht, the Netherlands
| | - Matthijs K C Hesselink
- Department of Human Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, Maastricht, the Netherlands
| | - Patrick Schrauwen
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, P. O. Box 616, 6200MD, Maastricht, the Netherlands
| | - Joris Hoeks
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, P. O. Box 616, 6200MD, Maastricht, the Netherlands.
| |
Collapse
|
26
|
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.
Collapse
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.
| |
Collapse
|
27
|
Van Thienen R, Hespel P. Enhanced muscular oxygen extraction in athletes exaggerates hypoxemia during exercise in hypoxia. J Appl Physiol (1985) 2015; 120:351-61. [PMID: 26607244 DOI: 10.1152/japplphysiol.00210.2015] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 11/22/2015] [Indexed: 01/11/2023] Open
Abstract
High rate of muscular oxygen utilization facilitates the development of hypoxemia during exercise at altitude. Because endurance training stimulates oxygen extraction capacity, we investigated whether endurance athletes are at higher risk to developing hypoxemia and thereby acute mountain sickness symptoms during exercise at simulated high altitude. Elite athletes (ATL; n = 8) and fit controls (CON; n = 7) cycled for 20 min at 100 W (EX100W), as well as performed an incremental maximal oxygen consumption test (EXMAX) in normobaric hypoxia (0.107 inspired O2 fraction) or normoxia (0.209 inspired O2 fraction). Cardiorespiratory responses, arterial Po2 (PaO2), and oxygenation status in m. vastus lateralis [tissue oxygenation index (TOIM)] and frontal cortex (TOIC) by near-infrared spectroscopy, were measured. Muscle O2 uptake rate was estimated from change in oxyhemoglobin concentration during a 10-min arterial occlusion in m. gastrocnemius. Maximal oxygen consumption in normoxia was 70 ± 2 ml·min(-1·)kg(-1) in ATL vs. 43 ± 2 ml·min(-1·)kg(-1) in CON, and in hypoxia decreased more in ATL (-41%) than in CON (-25%, P < 0.05). Both in normoxia at PaO2 of ∼95 Torr, and in hypoxia at PaO2 of ∼35 Torr, muscle O2 uptake was twofold higher in ATL than in CON (0.12 vs. 0.06 ml·min(-1)·100 g(-1); P < 0.05). During EX100W in hypoxia, PaO2 dropped to lower (P < 0.05) values in ATL (27.6 ± 0.7 Torr) than in CON (33.5 ± 1.0 Torr). During EXMAX, but not during EX100W, TOIM was ∼15% lower in ATL than in CON (P < 0.05). TOIC was similar between the groups at any time. This study shows that maintenance of high muscular oxygen extraction rate at very low circulating PaO2 stimulates the development of hypoxemia during submaximal exercise in hypoxia in endurance-trained individuals. This effect may predispose to premature development of acute mountain sickness symptoms during exercise at altitude.
Collapse
Affiliation(s)
- Ruud Van Thienen
- Exercise Physiology Research Group, Department of Kinesiology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Peter Hespel
- Exercise Physiology Research Group, Department of Kinesiology, Katholieke Universiteit Leuven, Leuven, Belgium
| |
Collapse
|
28
|
Emrani R, Rébillard A, Lefeuvre L, Gratas-Delamarche A, Davies KJA, Cillard J. The calcineurin antagonist RCAN1-4 is induced by exhaustive exercise in rat skeletal muscle. Free Radic Biol Med 2015; 87:290-9. [PMID: 26122706 DOI: 10.1016/j.freeradbiomed.2015.06.023] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Revised: 06/18/2015] [Accepted: 06/21/2015] [Indexed: 12/12/2022]
Abstract
The aim of this work was to study the regulation of the calcineurin antagonist regulator of calcineurin 1 (RCAN1) in rat skeletal muscles after exhaustive physical exercise, which is a physiological modulator of oxidative stress. Three skeletal muscles, namely extensor digitorum longus (EDL), gastrocnemius, and soleus, were investigated. Exhaustive exercise increased RCAN1-4 protein levels in EDL and gastrocnemius, but not in soleus. Protein oxidation as an index of oxidative stress was increased in EDL and gastrocnemius, but remained unchanged in soleus. However, lipid peroxidation was increased in all three muscles. CuZnSOD and catalase protein levels were increased at 3 h postexercise in soleus, whereas they remained unchanged in EDL and gastrocnemius. Calcineurin enzymatic activity declined in EDL and gastrocnemius but not in soleus, and its protein expression was decreased in all three muscles. The level of PGC1-α protein remained unchanged, whereas the protein expression of the transcription factor NFATc4 was decreased in all three muscles. Adiponectin expression was increased in all three muscles. RCAN1-4 expression in EDL and gastrocnemius muscles was augmented by the oxidative stress generated from exhaustive exercise. We propose that increased RCAN1-4 expression and the signal transduction pathways it regulates represent important components of the physiological adaptation to exercise-induced oxidative stress.
Collapse
Affiliation(s)
- Ramin Emrani
- Laboratory of Movement, Sport & Health Sciences (EA 1274), Faculty of Pharmacy, University Rennes 1, 35043 Rennes Cédex, France
| | - Amélie Rébillard
- Laboratory of Movement, Sport & Health Sciences, University Rennes 2, Ecole Normale Supérieure Rennes, 35170 Bruz, France
| | - Luz Lefeuvre
- Laboratory of Movement, Sport & Health Sciences, University Rennes 2, Ecole Normale Supérieure Rennes, 35170 Bruz, France
| | - Arlette Gratas-Delamarche
- Laboratory of Movement, Sport & Health Sciences, University Rennes 2, Ecole Normale Supérieure Rennes, 35170 Bruz, France
| | - Kelvin J A Davies
- Ethel Percy Andrus Gerontology Center, Leonard Davis School of Gerontology, and Division of Molecular and Computational Biology, Department of Biological Sciences, Dornsife College of Letters, Arts & Sciences, University of Southern California, Los Angeles, CA 90089-0191, USA
| | - Josiane Cillard
- Laboratory of Movement, Sport & Health Sciences (EA 1274), Faculty of Pharmacy, University Rennes 1, 35043 Rennes Cédex, France.
| |
Collapse
|
29
|
Constantinescu S, Turcotte LP. Amelioration of palmitate-induced metabolic dysfunction in L6 muscle cells expressing low levels of receptor-interacting protein 140. Can J Physiol Pharmacol 2015; 93:913-22. [PMID: 26406163 DOI: 10.1139/cjpp-2015-0020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We have shown that reduced expression of receptor-interacting protein 140 (RIP140) alters the regulation of fatty-acid (FA) oxidation in muscle. To determine whether a high level of FA availability alters the effects of RIP140 on metabolic regulation, L6 myotubes were transfected with or without RNA interference oligonucleotide sequences to reduce RIP140 expression, and then incubated with high levels of palmitic acid, with or without insulin. High levels of palmitate reduced basal (53%-58%) and insulin-treated (24%-44%) FA uptake and oxidation, and increased basal glucose uptake (88%). In cells incubated with high levels of palmitate, low RIP140 increased basal FA uptake and insulin-treated FA oxidation and glucose uptake, and decreased basal glucose uptake and insulin-treated FA uptake. Under basal conditions, low RIP140 increased the mRNA content of FAT/CD36 (159%) and COX4 (61%), as well as the protein content of Nur77 (68%), whereas the mRNA expression of FGF21 (50%) was decreased, as was the protein content of CPT1b (35%) and FGF21 (44%). Under insulin-treated conditions, low RIP140 expression increased the mRNA content of MCAD (84%) and Nur77 (84%), as well as the protein content of Nur77 (23%). Thus, a low level of RIP140 restores the rates of FA uptake in the basal state, in part via a reduction in upstream insulin signaling. Our data also indicate that the protein expression of Nur77 may be modulated by RIP140 when muscle cells are metabolically challenged by high levels of palmitate.
Collapse
Affiliation(s)
- Silvana Constantinescu
- b Department of Math and Science, Marymount California University, Rancho Palos Verdes, California, USA
| | - Lorraine P Turcotte
- a Department of Biological Sciences, Human and Evolutionary Biology, Dana and David Dornsife College of Letters, Arts and Sciences, University of Southern California, 3560 Watt Way, PED 107, Los Angeles, CA 90089-0652, USA
| |
Collapse
|
30
|
Overmyer KA, Evans CR, Qi NR, Minogue CE, Carson JJ, Chermside-Scabbo CJ, Koch LG, Britton SL, Pagliarini DJ, Coon JJ, Burant CF. Maximal oxidative capacity during exercise is associated with skeletal muscle fuel selection and dynamic changes in mitochondrial protein acetylation. Cell Metab 2015; 21:468-78. [PMID: 25738461 PMCID: PMC4350023 DOI: 10.1016/j.cmet.2015.02.007] [Citation(s) in RCA: 141] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2014] [Revised: 12/16/2014] [Accepted: 02/06/2015] [Indexed: 01/24/2023]
Abstract
Maximal exercise-associated oxidative capacity is strongly correlated with health and longevity in humans. Rats selectively bred for high running capacity (HCR) have improved metabolic health and are longer-lived than their low-capacity counterparts (LCR). Using metabolomic and proteomic profiling, we show that HCR efficiently oxidize fatty acids (FAs) and branched-chain amino acids (BCAAs), sparing glycogen and reducing accumulation of short- and medium-chain acylcarnitines. HCR mitochondria have reduced acetylation of mitochondrial proteins within oxidative pathways at rest, and there is rapid protein deacetylation with exercise, which is greater in HCR than LCR. Fluxomic analysis of valine degradation with exercise demonstrates a functional role of differential protein acetylation in HCR and LCR. Our data suggest that efficient FA and BCAA utilization contribute to high intrinsic exercise capacity and the health and longevity benefits associated with enhanced fitness.
Collapse
Affiliation(s)
- Katherine A Overmyer
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA; Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Charles R Evans
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA
| | - Nathan R Qi
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA
| | | | - Joshua J Carson
- Department of Biochemistry, University of Wisconsin, Madison, WI 53706, USA
| | | | - Lauren G Koch
- Department of Anesthesiology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Steven L Britton
- Department of Anesthesiology, University of Michigan, Ann Arbor, MI 48109, USA
| | - David J Pagliarini
- Department of Biochemistry, University of Wisconsin, Madison, WI 53706, USA
| | - Joshua J Coon
- Department of Biochemistry, University of Wisconsin, Madison, WI 53706, USA; Department of Biomolecular Chemistry, University of Wisconsin, Madison, WI 53706, USA; Genome Center of Wisconsin, University of Wisconsin, Madison, WI 53706, USA
| | - Charles F Burant
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA; Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA.
| |
Collapse
|
31
|
Kemp GJ, Ahmad RE, Nicolay K, Prompers JJ. Quantification of skeletal muscle mitochondrial function by 31P magnetic resonance spectroscopy techniques: a quantitative review. Acta Physiol (Oxf) 2015; 213:107-44. [PMID: 24773619 DOI: 10.1111/apha.12307] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2013] [Revised: 12/30/2013] [Accepted: 04/23/2014] [Indexed: 12/16/2022]
Abstract
Magnetic resonance spectroscopy (MRS) can give information about cellular metabolism in vivo which is difficult to obtain in other ways. In skeletal muscle, non-invasive (31) P MRS measurements of the post-exercise recovery kinetics of pH, [PCr], [Pi] and [ADP] contain valuable information about muscle mitochondrial function and cellular pH homeostasis in vivo, but quantitative interpretation depends on understanding the underlying physiology. Here, by giving examples of the analysis of (31) P MRS recovery data, by some simple computational simulation, and by extensively comparing data from published studies using both (31) P MRS and invasive direct measurements of muscle O2 consumption in a common analytical framework, we consider what can be learnt quantitatively about mitochondrial metabolism in skeletal muscle using MRS-based methodology. We explore some technical and conceptual limitations of current methods, and point out some aspects of the physiology which are still incompletely understood.
Collapse
Affiliation(s)
- G. J. Kemp
- Department of Musculoskeletal Biology, and Magnetic Resonance and Image Analysis Research Centre; University of Liverpool; Liverpool UK
| | - R. E. Ahmad
- Department of Musculoskeletal Biology, and Magnetic Resonance and Image Analysis Research Centre; University of Liverpool; Liverpool UK
| | - K. Nicolay
- Biomedical NMR; Department of Biomedical Engineering; Eindhoven University of Technology; Eindhoven the Netherlands
| | - J. J. Prompers
- Biomedical NMR; Department of Biomedical Engineering; Eindhoven University of Technology; Eindhoven the Netherlands
| |
Collapse
|
32
|
Fletcher JA, Meers GM, Linden MA, Kearney ML, Morris EM, Thyfault JP, Rector RS. Impact of various exercise modalities on hepatic mitochondrial function. Med Sci Sports Exerc 2014; 46:1089-97. [PMID: 24263979 DOI: 10.1249/mss.0000000000000223] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
PURPOSE Hepatic mitochondrial adaptations to exercise are largely unknown. In this study, we sought to determine the effects of various exercise modalities on measures of hepatic mitochondrial function and metabolism. METHODS Male Sprague-Dawley rats were randomly assigned (n = 8-10 per group) into sedentary (SED), voluntary wheel running (VWR), VWR with food pulled during the dark cycle (VMR-OF), treadmill endurance exercise (TM-END; 30 m·min, 12% gradient, 60 min·d, 5 d·wk), or treadmill interval sprint training (TM-IST; 50 m·min, 12% gradient, 6 × 2.5 min bouts, 5 d·wk) groups for a 4-wk intervention. RESULTS Hepatic mitochondrial state 3 and maximal uncoupled respiration were significantly (P < 0.05) increased in all four exercise groups compared with SED animals. In addition, hepatic mitochondrial [1-C] pyruvate oxidation to CO2, an index of pyruvate dehydrogenase (PDH) activity, was significantly increased in VWR-OF, TM-END, and TM-IST rats (P < 0.05), whereas exercise-induced increases in [2-C] pyruvate oxidation and [1-C] palmitate oxidation to CO2 did not reach statistical significance. Hepatic mitochondrial sirtuin 3 protein content, which putatively increases activity of mitochondrial proteins, was elevated in the VWR, VWR-OF, and TM-END groups (P < 0.05). In addition, only VWR-OF animals experienced increases in hepatic cytochrome c protein content and phosphoenolpyruvate carboxykinase mRNA, whereas PGC-1α mRNA expression and phospho-CREB protein content was increased in VWR-OF and TM-END groups. CONCLUSION Four weeks of exercise training, regardless of exercise modality, significantly increased hepatic mitochondrial respiration and evoked other unique improvements in mitochondrial metabolism that do not appear to be dependent on increases in mitochondrial content.
Collapse
Affiliation(s)
- Justin A Fletcher
- 1Harry S. Truman Memorial Veterans' Hospital, Columbia, MO; 2Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, MO; and 3Division of Gastroenterology and Hepatology, Department of Internal Medicine, University of Missouri, Columbia, MO
| | | | | | | | | | | | | |
Collapse
|
33
|
Trevellin E, Scorzeto M, Olivieri M, Granzotto M, Valerio A, Tedesco L, Fabris R, Serra R, Quarta M, Reggiani C, Nisoli E, Vettor R. Exercise training induces mitochondrial biogenesis and glucose uptake in subcutaneous adipose tissue through eNOS-dependent mechanisms. Diabetes 2014; 63:2800-11. [PMID: 24622799 DOI: 10.2337/db13-1234] [Citation(s) in RCA: 118] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Insulin resistance and obesity are associated with a reduction of mitochondrial content in various tissues of mammals. Moreover, a reduced nitric oxide (NO) bioavailability impairs several cellular functions, including mitochondrial biogenesis and insulin-stimulated glucose uptake, two important mechanisms of body adaptation in response to physical exercise. Although these mechanisms have been thoroughly investigated in skeletal muscle and heart, few studies have focused on the effects of exercise on mitochondria and glucose metabolism in adipose tissue. In this study, we compared the in vivo effects of chronic exercise in subcutaneous adipose tissue of wild-type (WT) and endothelial NO synthase (eNOS) knockout (eNOS(-/-)) mice after a swim training period. We then investigated the in vitro effects of NO on mouse 3T3-L1 and human subcutaneous adipose tissue-derived adipocytes after a chronic treatment with an NO donor: diethylenetriamine-NO (DETA-NO). We observed that swim training increases mitochondrial biogenesis, mitochondrial DNA content, and glucose uptake in subcutaneous adipose tissue of WT but not eNOS(-/-) mice. Furthermore, we observed that DETA-NO promotes mitochondrial biogenesis and elongation, glucose uptake, and GLUT4 translocation in cultured murine and human adipocytes. These results point to the crucial role of the eNOS-derived NO in the metabolic adaptation of subcutaneous adipose tissue to exercise training.
Collapse
Affiliation(s)
- Elisabetta Trevellin
- Internal Medicine 3, Endocrine-Metabolic Laboratory, Department of Medicine DIMED, University of Padua, Padua, Italy
| | - Michele Scorzeto
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Massimiliano Olivieri
- Internal Medicine 3, Endocrine-Metabolic Laboratory, Department of Medicine DIMED, University of Padua, Padua, Italy
| | - Marnie Granzotto
- Internal Medicine 3, Endocrine-Metabolic Laboratory, Department of Medicine DIMED, University of Padua, Padua, Italy
| | - Alessandra Valerio
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Laura Tedesco
- Center for Study and Research on Obesity, Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Roberto Fabris
- Internal Medicine 3, Endocrine-Metabolic Laboratory, Department of Medicine DIMED, University of Padua, Padua, Italy
| | - Roberto Serra
- Internal Medicine 3, Endocrine-Metabolic Laboratory, Department of Medicine DIMED, University of Padua, Padua, Italy
| | - Marco Quarta
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Carlo Reggiani
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Enzo Nisoli
- Center for Study and Research on Obesity, Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Roberto Vettor
- Internal Medicine 3, Endocrine-Metabolic Laboratory, Department of Medicine DIMED, University of Padua, Padua, Italy
| |
Collapse
|
34
|
Moshkin MP, Akulov AE, Petrovski DV, Saik OV, Petrovskiy ED, Savelov AA, Koptyug IV. Proton magnetic resonance spectroscopy of brain metabolic shifts induced by acute administration of 2-deoxy-d-glucose and lipopolysaccharides. NMR IN BIOMEDICINE 2014; 27:399-405. [PMID: 24493094 DOI: 10.1002/nbm.3074] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 12/05/2013] [Accepted: 12/11/2013] [Indexed: 06/03/2023]
Abstract
In vivo proton magnetic resonance spectroscopy ((1) H MRS) of outbred stock ICR male mice (originating from the Institute of Cancer Research) was used to study the brain (hippocampus) metabolic response to the pro-inflammatory stimulus and to the acute deficiency of the available energy, which was confirmed by measuring the maximum oxygen consumption. Inhibition of glycolysis by means of an injection with 2-deoxy-d-glucose (2DG) reduced the levels of gamma-aminobutyric acid (GABA, p < 0.05, in comparison with control, least significant difference (LSD) test), N-acetylaspartate (NAA, p < 0.05, LSD test) and choline compounds, and at the same time increased the levels of glutamate and glutamine. An opposite effect was found after injection with bacterial lipopolysaccharide (LPS) - a very common pro-inflammatory inducer. An increase in the amounts of GABA, NAA and choline compounds in the brain occurred in mice treated with LPS. Different metabolic responses to the energy deficiency and the pro-inflammatory stimuli can explain the contradictory results of the brain (1) H MRS studies under neurodegenerative pathology, which is accompanied by both mitochondrial dysfunction and inflammation. The prevalence of the excitatory metabolites such as glutamate and glutamine in 2DG treated mice is in good agreement with excitation observed during temporary reduction of the available energy under acute hypoxia or starvation. In turn, LPS, as an inducer of the sickness behavior, which was manifested as depression, sleepiness, loss of appetite etc., shifts the brain metabolic pattern toward the prevalence of the inhibitory neurotransmitter GABA.
Collapse
Affiliation(s)
- Mikhail P Moshkin
- Institute of Cytology and Genetics, Siberian Branch of RAS, Novosibirsk, Russia
| | | | | | | | | | | | | |
Collapse
|
35
|
Schlagowski AI, Singh F, Charles AL, Gali Ramamoorthy T, Favret F, Piquard F, Geny B, Zoll J. Mitochondrial uncoupling reduces exercise capacity despite several skeletal muscle metabolic adaptations. J Appl Physiol (1985) 2014; 116:364-75. [DOI: 10.1152/japplphysiol.01177.2013] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The effects of mitochondrial uncoupling on skeletal muscle mitochondrial adaptation and maximal exercise capacity are unknown. In this study, rats were divided into a control group (CTL, n = 8) and a group treated with 2,4-dinitrophenol, a mitochondrial uncoupler, for 28 days (DNP, 30 mg·kg−1·day−1in drinking water, n = 8). The DNP group had a significantly lower body mass ( P < 0.05) and a higher resting oxygen uptake (V̇o2, P < 0.005). The incremental treadmill test showed that maximal running speed and running economy ( P < 0.01) were impaired but that maximal V̇o2(V̇o2max) was higher in the DNP-treated rats ( P < 0.05). In skinned gastrocnemius fibers, basal respiration (V0) was higher ( P < 0.01) in the DNP-treated animals, whereas the acceptor control ratio (ACR, Vmax/V0) was significantly lower ( P < 0.05), indicating a reduction in OXPHOS efficiency. In skeletal muscle, DNP activated the mitochondrial biogenesis pathway, as indicated by changes in the mRNA expression of PGC1-α and -β, NRF-1 and −2, and TFAM, and increased the mRNA expression of cytochrome oxidase 1 ( P < 0.01). The expression of two mitochondrial proteins (prohibitin and Ndufs 3) was higher after DNP treatment. Mitochondrial fission 1 protein (Fis-1) was increased in the DNP group ( P < 0.01), but mitofusin-1 and -2 were unchanged. Histochemical staining for NADH dehydrogenase and succinate dehydrogenase activity in the gastrocnemius muscle revealed an increase in the proportion of oxidative fibers after DNP treatment. Our study shows that mitochondrial uncoupling induces several skeletal muscle adaptations, highlighting the role of mitochondrial coupling as a critical factor for maximal exercise capacities. These results emphasize the importance of investigating the qualitative aspects of mitochondrial function in addition to the amount of mitochondria.
Collapse
Affiliation(s)
- A. I. Schlagowski
- University of Strasbourg, Faculty of Medicine, FMTS, EA 3072, Strasbourg, France
- CHRU of Strasbourg, Physiology and Functional Explorations Department, New Civil Hospital, Strasbourg, France; and
| | - F. Singh
- University of Strasbourg, Faculty of Medicine, FMTS, EA 3072, Strasbourg, France
| | - A. L. Charles
- University of Strasbourg, Faculty of Medicine, FMTS, EA 3072, Strasbourg, France
| | - T. Gali Ramamoorthy
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Department of Physiological Genetics, Illkirch, France
| | - F. Favret
- University of Strasbourg, Faculty of Medicine, FMTS, EA 3072, Strasbourg, France
- CHRU of Strasbourg, Physiology and Functional Explorations Department, New Civil Hospital, Strasbourg, France; and
| | - F. Piquard
- University of Strasbourg, Faculty of Medicine, FMTS, EA 3072, Strasbourg, France
- CHRU of Strasbourg, Physiology and Functional Explorations Department, New Civil Hospital, Strasbourg, France; and
| | - B. Geny
- University of Strasbourg, Faculty of Medicine, FMTS, EA 3072, Strasbourg, France
- CHRU of Strasbourg, Physiology and Functional Explorations Department, New Civil Hospital, Strasbourg, France; and
| | - J. Zoll
- University of Strasbourg, Faculty of Medicine, FMTS, EA 3072, Strasbourg, France
- CHRU of Strasbourg, Physiology and Functional Explorations Department, New Civil Hospital, Strasbourg, France; and
| |
Collapse
|
36
|
Befroy DE, Perry RJ, Jain N, Dufour S, Cline GW, Trimmer JK, Brosnan J, Rothman DL, Petersen KF, Shulman GI. Direct assessment of hepatic mitochondrial oxidative and anaplerotic fluxes in humans using dynamic 13C magnetic resonance spectroscopy. Nat Med 2014; 20:98-102. [PMID: 24317120 PMCID: PMC3947269 DOI: 10.1038/nm.3415] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Accepted: 10/29/2013] [Indexed: 12/11/2022]
Abstract
Despite the central role of the liver in the regulation of glucose and lipid metabolism, there are currently no methods to directly assess hepatic oxidative metabolism in humans in vivo. By using a new (13)C-labeling strategy in combination with (13)C magnetic resonance spectroscopy, we show that rates of mitochondrial oxidation and anaplerosis in human liver can be directly determined noninvasively. Using this approach, we found the mean rates of hepatic tricarboxylic acid (TCA) cycle flux (VTCA) and anaplerotic flux (VANA) to be 0.43 ± 0.04 μmol g(-1) min(-1) and 0.60 ± 0.11 μmol g(-1) min(-1), respectively, in twelve healthy, lean individuals. We also found the VANA/VTCA ratio to be 1.39 ± 0.22, which is severalfold lower than recently published estimates using an indirect approach. This method will be useful for understanding the pathogenesis of nonalcoholic fatty liver disease and type 2 diabetes, as well as for assessing the effectiveness of new therapies targeting these pathways in humans.
Collapse
Affiliation(s)
- Douglas E Befroy
- 1] Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut, USA. [2] Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA. [3]
| | - Rachel J Perry
- 1] Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA. [2] Department of Cellular & Molecular Physiology, Yale University School of Medicine, New Haven, Connecticut, USA. [3]
| | - Nimit Jain
- Department of Biomedical Engineering, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Sylvie Dufour
- Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Gary W Cline
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | | | | | - Douglas L Rothman
- 1] Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut, USA. [2] Department of Biomedical Engineering, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Kitt Falk Petersen
- 1] Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA. [2] Novo Nordisk Foundation Center for Basic Metabolic Research, Copenhagen, Denmark
| | - Gerald I Shulman
- 1] Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA. [2] Department of Cellular & Molecular Physiology, Yale University School of Medicine, New Haven, Connecticut, USA. [3] Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut, USA. [4] Novo Nordisk Foundation Center for Basic Metabolic Research, Copenhagen, Denmark
| |
Collapse
|
37
|
Holloszy JO. Regulation of mitochondrial biogenesis and GLUT4 expression by exercise. Compr Physiol 2013; 1:921-40. [PMID: 23737207 DOI: 10.1002/cphy.c100052] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Endurance exercise training can induce large increases mitochondria and the GLUT4 isoform of the glucose transporter in skeletal muscle. For a long time after the discovery in the 1960s that exercise results in an increase in muscle mitochondria, there was no progress in elucidation of the mechanisms involved. The reason for this lack of progress was that nothing was known regarding how expression of the genes-encoding mitochondrial proteins is coordinately regulated. This situation changed rapidly after discovery of transcription factors that control transcription of genes-encoding mitochondrial proteins and, most importantly, the discovery of peroxisome proliferator-gamma coactivator-1α (PGC-1α). This transcription coactivator binds to and activates transcription factors that regulate transcription of genes-encoding mitochondrial proteins. Thus, PGC-1α activates and coordinates mitochondrial biogenesis. It is now known that exercise rapidly activates and induces increased expression of PGC-1α. The exercise-generated signals that lead to PGC-1α activation and increased expression are the increases in cytosolic Ca(2+) and decreases in ATP and creatine phosphate (∼P). Ca(2+) mediates its effect by activating CAMKII, while the decrease in ∼P mediates its effect via activation of AMPK. Expression of the GLUT4 isoform of the glucose transporter is regulated in parallel with mitochondrial biogenesis via the same signaling pathways. This review describes what is known regarding the regulation of mitochondrial biogenesis and GLUT4 expression by exercise. A major component of this review deals with the physiological and metabolic consequences of the exercise-induced increase in mitochondria and GLUT4.
Collapse
Affiliation(s)
- John O Holloszy
- Division of Geriatrics and Nutritional Sciences, Washington University School of Medicine, St. Louis, Missouri, USA.
| |
Collapse
|
38
|
Christensen B, Nellemann B, Larsen MS, Thams L, Sieljacks P, Vestergaard PF, Bibby BM, Vissing K, Stødkilde-Jørgensen H, Pedersen SB, Møller N, Nielsen S, Jessen N, Jørgensen JOL. Whole body metabolic effects of prolonged endurance training in combination with erythropoietin treatment in humans: a randomized placebo controlled trial. Am J Physiol Endocrinol Metab 2013; 305:E879-89. [PMID: 23921143 DOI: 10.1152/ajpendo.00269.2013] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
UNLABELLED Erythropoietin (Epo) administration improves aerobic exercise capacity and insulin sensitivity in renal patients and also increases resting energy expenditure (REE). Similar effects are observed in response to endurance training. The aim was to compare the effects of endurance training with erythropoiesis-stimulating agent (ESA) treatment in healthy humans. Thirty-six healthy untrained men were randomized to 10 wk of either: 1) placebo (n = 9), 2) ESA (n = 9), 3) endurance training (n = 10), or 4) ESA and endurance training (n = 8). In a single-blinded design, ESA/placebo was injected one time weekly. Training consisted of biking for 1 h at 65% of wattmax three times per week. Measurements performed before and after the intervention were as follows: body composition, maximal oxygen uptake, insulin sensitivity, REE, and palmitate turnover. Uncoupling protein 2 (UCP2) mRNA levels were assessed in skeletal muscle. Fat mass decreased after training (P = 0.003), whereas ESA induced a small but significant increase in intrahepatic fat (P = 0.025). Serum free fatty acid (FFA) levels and palmitate turnover decreased significantly in response to training, whereas the opposite pattern was found after ESA. REE corrected for lean body mass increased in response to ESA and training, and muscle UCP2 mRNA levels increased after ESA (P = 0.035). Insulin sensitivity increased only after training (P = 0.011). IN CONCLUSION 1) insulin sensitivity is not improved after ESA treatment despite improved exercise capacity, 2) the calorigenic effects of ESA may be related to increased UCP2 gene expression in skeletal muscle, and 3) training and ESA exert opposite effects on lipolysis under basal conditions, increased FFA levels and liver fat fraction was observed after ESA treatment.
Collapse
Affiliation(s)
- Britt Christensen
- Department of Endocrinology and Internal Medicine, NBG/THG, Aarhus University Hospital, Aarhus, Denmark
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
39
|
Barbieri E, Sestili P, Vallorani L, Guescini M, Calcabrini C, Gioacchini AM, Annibalini G, Lucertini F, Piccoli G, Stocchi V. Mitohormesis in muscle cells: a morphological, molecular, and proteomic approach. Muscles Ligaments Tendons J 2013; 3:254-266. [PMID: 24596688 PMCID: PMC3940498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Low-level oxidative stress induces an adaptive response commonly defined as hormesis; this type of stress is often related to reactive oxygen species (ROS) originating from the mitochondrial respiratory chain (mitochondrial hormesis or mitohormesis). The accumulation of transient low doses of ROS either through chronic physical activity or caloric restriction influences signaling from the mitochondrial compartment to the cell, reduces glucose metabolism, induces mitochondrial metabolism, increases stress resistance and ultimately, increases lifespan. Mitochondrial formation of presumably harmful levels (chronic and/or excessive) of ROS within skeletal muscle has been observed in insulin resistance of obese subjects, type 2 diabetes mellitus, as well as in impaired muscle function associated with normal aging. Advances in mitochondrial bioimaging combined with mitochondrial biochemistry and proteome research have broadened our knowledge of specific cellular signaling and other related functions of the mitochondrial behavior. In this review, we describe mitochondrial remodeling in response to different degrees of oxidative insults induced in vitro in myocytes and in vivo in skeletal muscle, focusing on the potential application of a combined morphological and biochemical approach. The use of such technologies could yield benefits for our overall understanding of physiology for biotechnological research related to drug design, physical activity prescription and significant lifestyle changes.
Collapse
Affiliation(s)
- Elena Barbieri
- Corresponding author: Elena Barbieri, Department of Biomolecular Sciences, Division of Exercise and Health Sciences, University Carlo Bo, Via I Maggetti, 26, 61029 Urbino, Italy, E-mail:
| | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Egger A, Kreis R, Allemann S, Stettler C, Diem P, Buehler T, Boesch C, Christ ER. The effect of aerobic exercise on intrahepatocellular and intramyocellular lipids in healthy subjects. PLoS One 2013; 8:e70865. [PMID: 23967125 PMCID: PMC3743875 DOI: 10.1371/journal.pone.0070865] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Accepted: 06/21/2013] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Intrahepatocellular (IHCL) and intramyocellular (IMCL) lipids are ectopic lipid stores. Aerobic exercise results in IMCL utilization in subjects over a broad range of exercise capacity. IMCL and IHCL have been related to impaired insulin action at the skeletal muscle and hepatic level, respectively. The acute effect of aerobic exercise on IHCL is unknown. Possible regulatory factors include exercise capacity, insulin sensitivity and fat availability subcutaneous and visceral fat mass). AIM To concomitantly investigate the effect of aerobic exercise on IHCL and IMCL in healthy subjects, using Magnetic Resonance spectroscopy. METHODS Normal weight, healthy subjects were included. Visit 1 consisted of a determination of VO2max on a treadmill. Visit 2 comprised the assessment of hepatic and peripheral insulin sensitivity by a two-step hyperinsulinaemic euglycaemic clamp. At Visit 3, subcutaneous and visceral fat mass were assessed by whole body MRI, IHCL and IMCL before and after a 2-hours aerobic exercise (50% of VO(2max)) using ¹H-MR-spectroscopy. RESULTS Eighteen volunteers (12M, 6F) were enrolled in the study (age, 37.6±3.2 years, mean±SEM; VO(2max), 53.4±2.9 mL/kg/min). Two hours aerobic exercise resulted in a significant decrease in IMCL (-22.6±3.3, % from baseline) and increase in IHCL (+34.9±7.6, % from baseline). There was no significant correlation between the exercise-induced changes in IMCL and IHCL and exercise capacity, subcutaneous and visceral fat mass and hepatic or peripheral insulin sensitivity. CONCLUSIONS IMCL and IHCL are flexible ectopic lipid stores that are acutely influenced by physical exercise, albeit in different directions. TRIAL REGISTRATION ClinicalTrial.gov NCT00491582.
Collapse
Affiliation(s)
- Andrea Egger
- Division of Endocrinology, Diabetology and Clinical Nutrition, University Hospital of Bern, Inselspital, Bern, Switzerland
| | - Roland Kreis
- Department of Clinical Research, Magnetic Resonance Spectroscopy and Methodology, University of Bern, Bern, Switzerland
| | - Sabin Allemann
- Division of Endocrinology, Diabetology and Clinical Nutrition, University Hospital of Bern, Inselspital, Bern, Switzerland
| | - Christoph Stettler
- Division of Endocrinology, Diabetology and Clinical Nutrition, University Hospital of Bern, Inselspital, Bern, Switzerland
| | - Peter Diem
- Division of Endocrinology, Diabetology and Clinical Nutrition, University Hospital of Bern, Inselspital, Bern, Switzerland
| | - Tania Buehler
- Department of Clinical Research, Magnetic Resonance Spectroscopy and Methodology, University of Bern, Bern, Switzerland
| | - Chris Boesch
- Department of Clinical Research, Magnetic Resonance Spectroscopy and Methodology, University of Bern, Bern, Switzerland
| | - Emanuel R. Christ
- Division of Endocrinology, Diabetology and Clinical Nutrition, University Hospital of Bern, Inselspital, Bern, Switzerland
- * E-mail:
| |
Collapse
|
41
|
Thrush AB, Dent R, McPherson R, Harper ME. Implications of mitochondrial uncoupling in skeletal muscle in the development and treatment of obesity. FEBS J 2013; 280:5015-29. [DOI: 10.1111/febs.12399] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 06/03/2013] [Accepted: 06/17/2013] [Indexed: 12/13/2022]
Affiliation(s)
- A. Brianne Thrush
- Department of Biochemistry, Microbiology and Immunology; Faculty of Medicine; University of Ottawa; Ontario; Canada
| | - Robert Dent
- Ottawa Hospital Weight Management Clinic; Ottawa Hospital; Ontario; Canada
| | | | - Mary-Ellen Harper
- Department of Biochemistry, Microbiology and Immunology; Faculty of Medicine; University of Ottawa; Ontario; Canada
| |
Collapse
|
42
|
Barbosa MR, Sampaio IH, Teodoro BG, Sousa TA, Zoppi CC, Queiroz AL, Passos MA, Alberici LC, Teixeira FR, Manfiolli AO, Batista TM, Cappelli APG, Reis RI, Frasson D, Kettelhut IC, Parreiras-e-Silva LT, Costa-Neto CM, Carneiro EM, Curi R, Silveira LR. Hydrogen peroxide production regulates the mitochondrial function in insulin resistant muscle cells: effect of catalase overexpression. Biochim Biophys Acta Mol Basis Dis 2013; 1832:1591-604. [PMID: 23643711 DOI: 10.1016/j.bbadis.2013.04.029] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Revised: 03/29/2013] [Accepted: 04/11/2013] [Indexed: 01/06/2023]
Abstract
The mitochondrial redox state plays a central role in the link between mitochondrial overloading and insulin resistance. However, the mechanism by which the ROS induce insulin resistance in skeletal muscle cells is not completely understood. We examined the association between mitochondrial function and H2O2 production in insulin resistant cells. Our hypothesis is that the low mitochondrial oxygen consumption leads to elevated ROS production by a mechanism associated with reduced PGC1α transcription and low content of phosphorylated CREB. The cells were transfected with either the encoded sequence for catalase overexpression or the specific siRNA for catalase inhibition. After transfection, myotubes were incubated with palmitic acid (500μM) and the insulin response, as well as mitochondrial function and fatty acid metabolism, was determined. The low mitochondrial oxygen consumption led to elevated ROS production by a mechanism associated with β-oxidation of fatty acids. Rotenone was observed to reduce the ratio of ROS production. The elevated H2O2 production markedly decreased the PGC1α transcription, an effect that was accompanied by a reduced phosphorylation of Akt and CREB. The catalase transfection prevented the reduction in the phosphorylated level of Akt and upregulated the levels of phosphorylated CREB. The mitochondrial function was elevated and H2O2 production reduced, thus increasing the insulin sensitivity. The catalase overexpression improved mitochondrial respiration protecting the cells from fatty acid-induced, insulin resistance. This effect indicates that control of hydrogen peroxide production regulates the mitochondrial respiration preventing the insulin resistance in skeletal muscle cells by a mechanism associated with CREB phosphorylation and β-oxidation of fatty acids.
Collapse
Affiliation(s)
- Marina R Barbosa
- Department of Biochemistry and Immunology, University of Sao Paulo, Ribeirão Preto, Brazil
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
43
|
Bastiaansen JAM, Cheng T, Mishkovsky M, Duarte JMN, Comment A, Gruetter R. In vivo enzymatic activity of acetylCoA synthetase in skeletal muscle revealed by (13)C turnover from hyperpolarized [1-(13)C]acetate to [1-(13)C]acetylcarnitine. Biochim Biophys Acta Gen Subj 2013; 1830:4171-8. [PMID: 23545238 DOI: 10.1016/j.bbagen.2013.03.023] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 03/20/2013] [Accepted: 03/22/2013] [Indexed: 12/28/2022]
Abstract
BACKGROUND Acetate metabolism in skeletal muscle is regulated by acetylCoA synthetase (ACS). The main function of ACS is to provide cells with acetylCoA, a key molecule for numerous metabolic pathways including fatty acid and cholesterol synthesis and the Krebs cycle. METHODS Hyperpolarized [1-(13)C]acetate prepared via dissolution dynamic nuclear polarization was injected intravenously at different concentrations into rats. The (13)C magnetic resonance signals of [1-(13)C]acetate and [1-(13)C]acetylcarnitine were recorded in vivo for 1min. The kinetic rate constants related to the transformation of acetate into acetylcarnitine were deduced from the 3s time resolution measurements using two approaches, either mathematical modeling or relative metabolite ratios. RESULTS Although separated by two biochemical transformations, a kinetic analysis of the (13)C label flow from [1-(13)C]acetate to [1-(13)C]acetylcarnitine led to a unique determination of the activity of ACS. The in vivo Michaelis constants for ACS were KM=0.35±0.13mM and Vmax=0.199±0.031μmol/g/min. CONCLUSIONS The conversion rates from hyperpolarized acetate into acetylcarnitine were quantified in vivo and, although separated by two enzymatic reactions, these rates uniquely defined the activity of ACS. The conversion rates associated with ACS were obtained using two analytical approaches, both methods yielding similar results. GENERAL SIGNIFICANCE This study demonstrates the feasibility of directly measuring ACS activity in vivo and, since the activity of ACS can be affected by various pathological states such as cancer or diabetes, the proposed method could be used to non-invasively probe metabolic signatures of ACS in diseased tissue.
Collapse
|
44
|
Larsen RG, Befroy DE, Kent-Braun JA. High-intensity interval training increases in vivo oxidative capacity with no effect on P(i)→ATP rate in resting human muscle. Am J Physiol Regul Integr Comp Physiol 2012; 304:R333-42. [PMID: 23255590 DOI: 10.1152/ajpregu.00409.2012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Mitochondrial ATP production is vital for meeting cellular energy demand at rest and during periods of high ATP turnover. We hypothesized that high-intensity interval training (HIT) would increase ATP flux in resting muscle (VPi→ATP) in response to a single bout of exercise, whereas changes in the capacity for oxidative ATP production (Vmax) would require repeated bouts. Eight untrained men (27 ± 4 yr; peak oxygen uptake = 36 ± 4 ml·kg(-1)·min(-1)) performed six sessions of HIT (4-6 × 30-s bouts of all-out cycling with 4-min recovery). After standardized meals and a 10-h fast, VPi→ATP and Vmax of the vastus lateralis muscle were measured using phosphorus magnetic resonance spectroscopy at 4 Tesla. Measurements were obtained at baseline, 15 h after the first training session, and 15 h after completion of the sixth session. VPi→ATP was determined from the unidirectional flux between Pi and ATP, using the saturation transfer technique. The rate of phosphocreatine recovery (kPCr) following a maximal contraction was used to calculate Vmax. While kPCr and Vmax were unchanged after a single session of HIT, completion of six training sessions resulted in a ∼14% increase in muscle oxidative capacity (P ≤ 0.004). In contrast, neither a single nor six training sessions altered VPi→ATP (P = 0.74). This novel analysis of resting and maximal high-energy phosphate kinetics in vivo in response to HIT provides evidence that distinct aspects of human skeletal muscle metabolism respond differently to this type of training.
Collapse
Affiliation(s)
- Ryan G Larsen
- Department of Kinesiology, University of Massachusetts, Amherst, MA 01003, USA
| | | | | |
Collapse
|
45
|
Jacobs RA, Lundby C. Mitochondria express enhanced quality as well as quantity in association with aerobic fitness across recreationally active individuals up to elite athletes. J Appl Physiol (1985) 2012; 114:344-50. [PMID: 23221957 DOI: 10.1152/japplphysiol.01081.2012] [Citation(s) in RCA: 149] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Changes in skeletal muscle respiratory capacity parallel that of aerobic fitness. It is unknown whether mitochondrial content, alone, can fully account for these differences in skeletal muscle respiratory capacity. The aim of the present study was to examine quantitative and qualitative mitochondrial characteristics across four different groups (n = 6 each), separated by cardiorespiratory fitness. High-resolution respirometry was performed on muscle samples to compare respiratory capacity and efficiency in active, well-trained, highly trained, and elite individuals. Maximal exercise capacity (ml O(2)·min(-1)·kg(-1)) differed across all groups, with mean ± SD values of 51 ± 4, 64 ± 5, 71 ± 2, and 77 ± 3, respectively. Mitochondrial content assessed by citrate synthase activity was higher in elite trained compared with active and well-trained (29 ± 7 vs. 16 ± 4 and 19 ± 4 nmol·min(-1)·mg wet wt(-1), respectively). When normalizing respiration to mitochondrial content, the respiratory capacities during maximal fatty acid oxidation (P = 0.003), maximal state 3 respiration (P = 0.021), and total electron transport system capacity (P = 0.008) improved with respect to maximal exercise capacity. The coupling efficiency of β-oxidation, however, expressed no difference across groups. These data demonstrate the quantitative and qualitative differences that exist in skeletal muscle mitochondrial respiratory capacity and efficiency across individuals that differ in aerobic capacity. Mitochondrial-specific respiration capacities during β-oxidation, maximal oxidative phosphorylation, and electron transport system capacity all correspondingly improve with aerobic capacity, independent of mitochondrial content in human skeletal muscle.
Collapse
Affiliation(s)
- Robert A Jacobs
- Zurich Center for Integrative Human Physiology, Zurich, Switzerland.
| | | |
Collapse
|
46
|
Cnop M, Igoillo-Esteve M, Rai M, Begu A, Serroukh Y, Depondt C, Musuaya AE, Marhfour I, Ladrière L, Moles Lopez X, Lefkaditis D, Moore F, Brion JP, Cooper JM, Schapira AHV, Clark A, Koeppen AH, Marchetti P, Pandolfo M, Eizirik DL, Féry F. Central role and mechanisms of β-cell dysfunction and death in friedreich ataxia-associated diabetes. Ann Neurol 2012; 72:971-82. [PMID: 23280845 PMCID: PMC4900175 DOI: 10.1002/ana.23698] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Revised: 06/14/2012] [Accepted: 06/29/2012] [Indexed: 12/26/2022]
Abstract
OBJECTIVE Friedreich ataxia (FRDA) is an autosomal recessive neurodegenerative disease caused in almost all cases by homozygosity for a GAA trinucleotide repeat expansion in the frataxin gene. Frataxin is a mitochondrial protein involved in iron homeostasis. FRDA patients have a high prevalence of diabetes, the pathogenesis of which is not known. We aimed to evaluate the relative contribution of insulin resistance and β-cell failure and the pathogenic mechanisms involved in FRDA diabetes. METHODS Forty-one FRDA patients, 26 heterozygous carriers of a GAA expansion, and 53 controls underwent oral and intravenous glucose tolerance tests. β-Cell proportion was quantified in postmortem pancreas sections from 9 unrelated FRDA patients. Using an in vitro disease model, we studied how frataxin deficiency affects β-cell function and survival. RESULTS FRDA patients had increased abdominal fat and were insulin resistant. This was not compensated for by increased insulin secretion, resulting in a markedly reduced disposition index, indicative of pancreatic β-cell failure. Loss of glucose tolerance was driven by β-cell dysfunction, which correlated with abdominal fatness. In postmortem pancreas sections, pancreatic islets of FRDA patients had a lower β-cell content. RNA interference-mediated frataxin knockdown impaired glucose-stimulated insulin secretion and induced apoptosis in rat β cells and human islets. Frataxin deficiency sensitized β cells to oleate-induced and endoplasmic reticulum stress-induced apoptosis, which could be prevented by the incretins glucagon-like peptide-1 and glucose-dependent insulinotropic polypeptide. INTERPRETATION Pancreatic β-cell dysfunction is central to diabetes development in FRDA as a result of mitochondrial dysfunction and higher sensitivity to metabolic and endoplasmic reticulum stress-induced β-cell death.
Collapse
Affiliation(s)
- Miriam Cnop
- Laboratory of Experimental Medicine, Universite Libre de Bruxelles, Brussels, Belgium.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
47
|
Hill BG, Benavides GA, Lancaster JR, Ballinger S, Dell’Italia L, Zhang J, Darley-Usmar VM. Integration of cellular bioenergetics with mitochondrial quality control and autophagy. Biol Chem 2012; 393:1485-1512. [PMID: 23092819 PMCID: PMC3594552 DOI: 10.1515/hsz-2012-0198] [Citation(s) in RCA: 346] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2012] [Accepted: 06/22/2012] [Indexed: 02/06/2023]
Abstract
Bioenergetic dysfunction is emerging as a cornerstone for establishing a framework for understanding the pathophysiology of cardiovascular disease, diabetes,cancer and neurodegeneration. Recent advances in cellular bioenergetics have shown that many cells maintain a substantial bioenergetic reserve capacity, which is a prospective index of ‘ healthy ’ mitochondrial populations.The bioenergetics of the cell are likely regulated by energy requirements and substrate availability. Additionally,the overall quality of the mitochondrial population and the relative abundance of mitochondria in cells and tissues also impinge on overall bioenergetic capacity and resistance to stress. Because mitochondria are susceptible to damage mediated by reactive oxygen/nitrogen and lipid species, maintaining a ‘ healthy ’ population of mitochondria through quality control mechanisms appears to be essential for cell survival under conditions of pathological stress. Accumulating evidence suggest that mitophagy is particularly important for preventing amplification of initial oxidative insults, which otherwise would further impair the respiratory chain or promote mutations in mitochondrial DNA (mtDNA). The processes underlying the regulation of mitophagy depend on several factors, including the integrity of mtDNA, electron transport chain activity, and the interaction and regulation of the autophagic machinery. The integration and interpretation of cellular bioenergetics in the context of mitochondrial quality control and genetics is the theme of this review.
Collapse
Affiliation(s)
- Bradford G. Hill
- Diabetes and Obesity Center, Institute of Molecular Cardiology, and Department of Medicine, University of Louisville, Louisville, KY
- Departments of Biochemistry and Molecular Biology and Physiology and Biophysics, University of Louisville, Louisville, KY
| | - Gloria A. Benavides
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294
- Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Jack R. Lancaster
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294
- Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL 35294
- Department of Anesthesiology, University of Alabama at Birmingham, Birmingham, AL 35294
- Department of Physiology and Biophysics, University of Alabama at Birmingham, Birmingham, AL 35294
- Department of Environmental Health Sciences, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Scott Ballinger
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294
- Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL 35294
- Department of Medicine, Center for Heart Failure Research, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Lou Dell’Italia
- Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL 35294
- Department of Medicine, Center for Heart Failure Research, University of Alabama at Birmingham, Birmingham, AL 35294
- Department of Veteran Affairs Medical Center, Birmingham, AL 35294
| | - Jianhua Zhang
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294
- Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL 35294
- Department of Veteran Affairs Medical Center, Birmingham, AL 35294
| | - Victor M. Darley-Usmar
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294
- Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL 35294
- Department of Medicine, Center for Heart Failure Research, University of Alabama at Birmingham, Birmingham, AL 35294
- Department of Environmental Health Sciences, University of Alabama at Birmingham, Birmingham, AL 35294
| |
Collapse
|
48
|
Freeman TC, Ivens A, Baillie JK, Beraldi D, Barnett MW, Dorward D, Downing A, Fairbairn L, Kapetanovic R, Raza S, Tomoiu A, Alberio R, Wu C, Su AI, Summers KM, Tuggle CK, Archibald AL, Hume DA. A gene expression atlas of the domestic pig. BMC Biol 2012; 10:90. [PMID: 23153189 PMCID: PMC3814290 DOI: 10.1186/1741-7007-10-90] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Accepted: 10/23/2012] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND This work describes the first genome-wide analysis of the transcriptional landscape of the pig. A new porcine Affymetrix expression array was designed in order to provide comprehensive coverage of the known pig transcriptome. The new array was used to generate a genome-wide expression atlas of pig tissues derived from 62 tissue/cell types. These data were subjected to network correlation analysis and clustering. RESULTS The analysis presented here provides a detailed functional clustering of the pig transcriptome where transcripts are grouped according to their expression pattern, so one can infer the function of an uncharacterized gene from the company it keeps and the locations in which it is expressed. We describe the overall transcriptional signatures present in the tissue atlas, where possible assigning those signatures to specific cell populations or pathways. In particular, we discuss the expression signatures associated with the gastrointestinal tract, an organ that was sampled at 15 sites along its length and whose biology in the pig is similar to human. We identify sets of genes that define specialized cellular compartments and region-specific digestive functions. Finally, we performed a network analysis of the transcription factors expressed in the gastrointestinal tract and demonstrate how they sub-divide into functional groups that may control cellular gastrointestinal development. CONCLUSIONS As an important livestock animal with a physiology that is more similar than mouse to man, we provide a major new resource for understanding gene expression with respect to the known physiology of mammalian tissues and cells. The data and analyses are available on the websites http://biogps.org and http://www.macrophages.com/pig-atlas.
Collapse
Affiliation(s)
- Tom C Freeman
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of
Edinburgh, Easter Bush, EH25 9PS, UK
| | - Alasdair Ivens
- Fios Genomics Ltd, ETTC, King's Buildings, Edinburgh EH9 3JL UK,Centre for Immunity, Infection and Evolution, University of Edinburgh Ashworth
Labs, King's Buildings, West Mains Road, Edinburgh EH9 3JT
| | - J Kenneth Baillie
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of
Edinburgh, Easter Bush, EH25 9PS, UK
| | - Dario Beraldi
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of
Edinburgh, Easter Bush, EH25 9PS, UK,Cancer Research UK, Cambridge Research Institute, Li Ka Shing Centre, Robinson
way, Cambridge, CB2 0RE, UK
| | - Mark W Barnett
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of
Edinburgh, Easter Bush, EH25 9PS, UK
| | - David Dorward
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of
Edinburgh, Easter Bush, EH25 9PS, UK
| | - Alison Downing
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of
Edinburgh, Easter Bush, EH25 9PS, UK
| | - Lynsey Fairbairn
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of
Edinburgh, Easter Bush, EH25 9PS, UK
| | - Ronan Kapetanovic
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of
Edinburgh, Easter Bush, EH25 9PS, UK
| | - Sobia Raza
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of
Edinburgh, Easter Bush, EH25 9PS, UK
| | - Andru Tomoiu
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of
Edinburgh, Easter Bush, EH25 9PS, UK
| | - Ramiro Alberio
- Division of Animal Sciences, School of Biosciences, University of Nottingham,
Sutton Bonington, Leicestershire LE12 5RD UK
| | - Chunlei Wu
- Department of Molecular and Experimental Medicine, The Scripps Research Institute,
MEM-216, 10550 North Torrey Pines Road, La Jolla, CA 92037 USA
| | - Andrew I Su
- Department of Molecular and Experimental Medicine, The Scripps Research Institute,
MEM-216, 10550 North Torrey Pines Road, La Jolla, CA 92037 USA
| | - Kim M Summers
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of
Edinburgh, Easter Bush, EH25 9PS, UK
| | | | - Alan L Archibald
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of
Edinburgh, Easter Bush, EH25 9PS, UK
| | - David A Hume
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of
Edinburgh, Easter Bush, EH25 9PS, UK
| |
Collapse
|
49
|
Larsen FJ, Schiffer TA, Weitzberg E, Lundberg JO. Regulation of mitochondrial function and energetics by reactive nitrogen oxides. Free Radic Biol Med 2012; 53:1919-28. [PMID: 22989554 DOI: 10.1016/j.freeradbiomed.2012.08.580] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Revised: 08/18/2012] [Accepted: 08/20/2012] [Indexed: 01/14/2023]
Abstract
Endogenous nitric oxide (NO) generated from L-arginine by NO synthase regulates mitochondrial function by binding to cytochrome c oxidase in competition with oxygen. This interaction can elicit a variety of intracellular signaling events of both physiological and pathophysiological significance. Recent lines of research demonstrate that inorganic nitrate and nitrite, derived from oxidized NO or from the diet, are metabolized in vivo to form NO and other bioactive nitrogen oxides with intriguing effects on cellular energetics and cytoprotection. Here we discuss the latest advances in our understanding of the roles of nitrate, nitrite, and NO in the modulation of mitochondrial function, with a particular focus on dietary nitrate and exercise.
Collapse
Affiliation(s)
- Filip J Larsen
- Department of Physiology and Pharmacology, Karolinska Institutet, 171 77 Stockholm, Sweden.
| | | | | | | |
Collapse
|
50
|
Befroy DE, Rothman DL, Petersen KF, Shulman GI. ³¹P-magnetization transfer magnetic resonance spectroscopy measurements of in vivo metabolism. Diabetes 2012; 61:2669-78. [PMID: 23093656 PMCID: PMC3478545 DOI: 10.2337/db12-0558] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Magnetic resonance spectroscopy offers a broad range of noninvasive analytical methods for investigating metabolism in vivo. Of these, the magnetization-transfer (MT) techniques permit the estimation of the unidirectional fluxes associated with metabolic exchange reactions. Phosphorus (³¹P) MT measurements can be used to examine the bioenergetic reactions of the creatine-kinase system and the ATP synthesis/hydrolysis cycle. Observations from our group and others suggest that the inorganic phosphate (P(i)) → ATP flux in skeletal muscle may be modulated by certain conditions, including aging, insulin resistance, and diabetes, and may reflect inherent alterations in mitochondrial metabolism. However, such effects on the P(i) → ATP flux are not universally observed under conditions in which mitochondrial function, assessed by other techniques, is impaired, and recent articles have raised concerns about the absolute magnitude of the measured reaction rates. As the application of ³¹P-MT techniques becomes more widespread, this article reviews the methodology and outlines our experience with its implementation in a variety of models in vivo. Also discussed are potential limitations of the technique, complementary methods for assessing oxidative metabolism, and whether the P(i) → ATP flux is a viable biomarker of metabolic function in vivo.
Collapse
Affiliation(s)
- Douglas E Befroy
- Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, CT, USA.
| | | | | | | |
Collapse
|