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Bajpeyi S, Apaflo JN, Rosas V, Sepulveda-Rivera K, Varela-Ramirez A, Covington JD, Galgani JE, Ravussin E. Effect of an acute long-duration exercise bout on skeletal muscle lipid droplet morphology, GLUT 4 protein, and perilipin protein expression. Eur J Appl Physiol 2023; 123:2771-2778. [PMID: 37368137 DOI: 10.1007/s00421-023-05266-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 06/21/2023] [Indexed: 06/28/2023]
Abstract
PURPOSE Smaller lipid droplet morphology and GLUT 4 protein expression have been associated with greater muscle oxidative capacity and glucose uptake, respectively. The main purpose of this study was to determine the effect of an acute long-duration exercise bout on skeletal muscle lipid droplet morphology, GLUT4, perilipin 3, and perilipin 5 expressions. METHODS Twenty healthy men (age 24.0 ± 1.0 years, BMI 23.6 ± 0.4 kg/m2) were recruited for the study. The participants were subjected to an acute bout of exercise on a cycle ergometer at 50% VO2max until they reached a total energy expenditure of 650 kcal. The study was conducted after an overnight fast. Vastus lateralis muscle biopsies were obtained before and immediately after exercise for immunohistochemical analysis to determine lipid, perilipin 3, perilipin 5, and GLUT4 protein contents while GLUT 4 mRNA was quantified using RT-qPCR. RESULTS Lipid droplet size decreased whereas total intramyocellular lipid content tended to reduce (p = 0.07) after an acute bout of endurance exercise. The density of smaller lipid droplets in the peripheral sarcoplasmic region significantly increased (0.584 ± 0.04 to 0.638 ± 0.08 AU; p = 0.01) while larger lipid droplets significantly decreased (p < 0.05). GLUT4 mRNA tended to increase (p = 0.05). There were no significant changes in GLUT 4, perilipin 3, and perilipin 5 protein levels. CONCLUSION The study demonstrates that exercise may impact metabolism by enhancing the quantity of smaller lipid droplets over larger lipid droplets.
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Affiliation(s)
- Sudip Bajpeyi
- Metabolic, Nutrition, and Exercise Research (MiNER) Laboratory, Department of Kinesiology, The University of Texas at El Paso, 500 University Ave, El Paso, TX, 79968, USA.
| | - Jehu N Apaflo
- Metabolic, Nutrition, and Exercise Research (MiNER) Laboratory, Department of Kinesiology, The University of Texas at El Paso, 500 University Ave, El Paso, TX, 79968, USA
| | - Victoria Rosas
- Metabolic, Nutrition, and Exercise Research (MiNER) Laboratory, Department of Kinesiology, The University of Texas at El Paso, 500 University Ave, El Paso, TX, 79968, USA
| | - Keisha Sepulveda-Rivera
- Metabolic, Nutrition, and Exercise Research (MiNER) Laboratory, Department of Kinesiology, The University of Texas at El Paso, 500 University Ave, El Paso, TX, 79968, USA
| | - Armando Varela-Ramirez
- The Cellular Characterization and Biorepository (CCB) Core Facility, Border Biomedical Research Center, Department of Biological Sciences, The University of Texas at El Paso, El Paso, TX, USA
| | - Jeffrey D Covington
- Department of Pathology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Jose E Galgani
- Faculty of Medicine, Pontificia Universidad Catolica de Chile, Santiago, Chile
| | - Eric Ravussin
- Laboratory of Skeletal Muscle Physiology, Pennington Biomedical Research Center, Baton Rouge, LA, USA
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2
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Mikłosz A, Łukaszuk B, Chabowski A, Górski J. Treadmill Running Changes Endothelial Lipase Expression: Insights from Gene and Protein Analysis in Various Striated Muscle Tissues and Serum. Biomolecules 2021; 11:biom11060906. [PMID: 34204548 PMCID: PMC8234415 DOI: 10.3390/biom11060906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 06/04/2021] [Accepted: 06/16/2021] [Indexed: 11/16/2022] Open
Abstract
Endothelial lipase (EL) is an enzyme capable of HDL phospholipids hydrolysis. Its action leads to a reduction in the serum high-density lipoprotein concentration, and thus, it exerts a pro-atherogenic effect. This study examines the impact of a single bout exercise on the gene and protein expression of the EL in skeletal muscles composed of different fiber types (the soleus—mainly type I, the red gastrocnemius—mostly IIA, and the white gastrocnemius—predominantly IIX fibers), as well as the diaphragm, and the heart. Wistar rats were subjected to a treadmill run: (1) t = 30 [min], V = 18 [m/min]; (2) t = 30 [min], V = 28 [m/min]; (3) t = 120 [min], V = 18 [m/min] (designated: M30, F30, and M120, respectively). We established EL expression in the total muscle homogenates in sedentary animals. Resting values could be ordered with the decreasing EL protein expression as follows: endothelium of left ventricle > diaphragm > red gastrocnemius > right ventricle > soleus > white gastrocnemius. Furthermore, we observed that even a single bout of exercise was capable of inducing changes in the mRNA and protein level of EL, with a clearer pattern observed for the former. After 30 min of running at either exercise intensity, the expression of EL transcript in all the cardiovascular components of muscles tested, except the soleus, was reduced in comparison to the respective sedentary control. The protein content of EL varied with the intensity and/or duration of the run in the studied whole tissue homogenates. The observed differences between EL expression in vascular beds of muscles may indicate the muscle-specific role of the lipase.
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Affiliation(s)
- Agnieszka Mikłosz
- Department of Physiology, Medical University of Bialystok, 12-222 Bialystok, Poland; (B.Ł.); (A.C.)
- Correspondence: ; Tel.: +48-85-746-55-85
| | - Bartłomiej Łukaszuk
- Department of Physiology, Medical University of Bialystok, 12-222 Bialystok, Poland; (B.Ł.); (A.C.)
| | - Adrian Chabowski
- Department of Physiology, Medical University of Bialystok, 12-222 Bialystok, Poland; (B.Ł.); (A.C.)
| | - Jan Górski
- Department of Basic Sciences, Lomza State University of Applied Sciences, 18-400 Lomza, Poland;
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Choudhary V, Schneiter R. A Unique Junctional Interface at Contact Sites Between the Endoplasmic Reticulum and Lipid Droplets. Front Cell Dev Biol 2021; 9:650186. [PMID: 33898445 PMCID: PMC8060488 DOI: 10.3389/fcell.2021.650186] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 03/09/2021] [Indexed: 12/19/2022] Open
Abstract
Lipid droplets (LDs) constitute compartments dedicated to the storage of metabolic energy in the form of neutral lipids. LDs originate from the endoplasmic reticulum (ER) with which they maintain close contact throughout their life cycle. These ER-LD junctions facilitate the exchange of both proteins and lipids between these two compartments. In recent years, proteins that are important for the proper formation of LDs and localize to ER-LD junctions have been identified. This junction is unique as it is generally believed to invoke a transition from the ER bilayer membrane to a lipid monolayer that delineates LDs. Proper formation of this junction requires the ordered assembly of proteins and lipids at specialized ER subdomains. Without such a well-ordered assembly of LD biogenesis factors, neutral lipids are synthesized throughout the ER membrane, resulting in the formation of aberrant LDs. Such ectopically formed LDs impact ER and lipid homeostasis, resulting in different types of lipid storage diseases. In response to starvation, the ER-LD junction recruits factors that tether the vacuole to these junctions to facilitate LD degradation. In addition, LDs maintain close contacts with peroxisomes and mitochondria for metabolic channeling of the released fatty acids toward beta-oxidation. In this review, we discuss the function of different components that ensure proper functioning of LD contact sites, their role in lipogenesis and lipolysis, and their relation to lipid storage diseases.
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Affiliation(s)
- Vineet Choudhary
- Department of Biotechnology, All India Institute of Medical Sciences (AIIMS), New Delhi, India
| | - Roger Schneiter
- Department of Biology, University of Fribourg, Fribourg, Switzerland
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4
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Affiliation(s)
- Maria Bohnert
- Institute of Cell Dynamics and Imaging, University of Münster
- Cells-in-Motion Cluster of Excellence (EXC 1003—CiM), University of Münster
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5
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Rezuş E, Burlui A, Cardoneanu A, Rezuş C, Codreanu C, Pârvu M, Rusu Zota G, Tamba BI. Inactivity and Skeletal Muscle Metabolism: A Vicious Cycle in Old Age. Int J Mol Sci 2020; 21:ijms21020592. [PMID: 31963330 PMCID: PMC7014434 DOI: 10.3390/ijms21020592] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 12/19/2019] [Accepted: 01/07/2020] [Indexed: 12/12/2022] Open
Abstract
Aging is an inevitable and gradually progressive process affecting all organs and systems. The musculoskeletal system makes no exception, elderly exhibit an increased risk of sarcopenia (low muscle mass),dynapenia (declining muscle strength), and subsequent disability. Whereas in recent years the subject of skeletal muscle metabolic decline in the elderly has been gathering interest amongst researchers, as well as medical professionals, there are many challenges yet to be solved in order to counteract the effects of aging on muscle function efficiently. Noteworthy, it has been shown that aging individuals exhibit a decline in skeletal muscle metabolism, a phenomenon which may be linked to a number of predisposing (risk) factors such as telomere attrition, epigenetic changes, mitochondrial dysfunction, sedentary behavior (leading to body composition alterations), age-related low-grade systemic inflammation (inflammaging), hormonal imbalance, as well as a hypoproteic diet (unable to counterbalance the repercussions of the age-related increase in skeletal muscle catabolism). The present review aims to discuss the relationship between old age and muscle wasting in an effort to highlight the modifications in skeletal muscle metabolism associated with aging and physical activity.
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Affiliation(s)
- Elena Rezuş
- Department of Rheumatology and Physiotherapy, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iaşi, Romania; (E.R.); (A.C.)
| | - Alexandra Burlui
- Department of Rheumatology and Physiotherapy, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iaşi, Romania; (E.R.); (A.C.)
- Correspondence:
| | - Anca Cardoneanu
- Department of Rheumatology and Physiotherapy, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iaşi, Romania; (E.R.); (A.C.)
| | - Ciprian Rezuş
- Department of Internal Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iaşi, Romania;
| | - Cătălin Codreanu
- Center for Rheumatic Diseases, “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania;
| | - Mirela Pârvu
- Department of Rheumatology and Physiotherapy,“George Emil Palade” University of Medicine, Pharmacy, Science and Technology, 540139 Târgu Mureş, Romania;
| | - Gabriela Rusu Zota
- Department of Pharmacology, Clinical Pharmacology and Algesiology, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iaşi, Romania;
| | - Bogdan Ionel Tamba
- Advanced Center for Research and Development in Experimental Medicine (CEMEX), “Grigore T. Popa” University of Medicine and Pharmacy, 700454 Iaşi, Romania;
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Shaw CS, Swinton C, Morales-Scholz MG, McRae N, Erftemeyer T, Aldous A, Murphy RM, Howlett KF. Impact of exercise training status on the fiber type-specific abundance of proteins regulating intramuscular lipid metabolism. J Appl Physiol (1985) 2020; 128:379-389. [PMID: 31917629 DOI: 10.1152/japplphysiol.00797.2019] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Endurance training enhances the capacity for fat oxidation during exercise due to increased utilization of intramuscular lipid (IMCL). This study quantitatively investigated the impact of exercise training status on muscle fiber type-specific abundance of regulatory proteins involved in IMCL utilization. Endurance-trained [n = 7 subjects, peak oxygen consumption (V̇o2peak) 62.6 ± 4.1 (SD) mL·min-1·kg-1] and non-endurance-trained (n = 8 subjects, V̇o2peak 44.9 ± 5.3 mL·min-1·kg-1) young men completed an incremental exercise test to determine maximal fat oxidation (MFO) and maximal oxygen uptake. Fiber type-specific IMCL content and protein abundance were assessed with immunofluorescence microscopy and immunoblot analysis of pooled single muscle fibers and whole muscle. Endurance-trained individuals displayed a higher MFO rate (0.45 ± 0.15 vs. 0.19 ± 0.07 g/min, P < 0.05), a greater proportion of type I muscle fibers, and higher IMCL content compared with untrained individuals (P < 0.05). Adipose triglyceride lipase, hormone-sensitive lipase, perilipin 2, perilipin 5, and hydroxyacyl-coenzyme A dehydrogenase abundances were ~2-3-fold higher in type I muscle fibers compared with type IIa fibers (P < 0.05). Correspondingly, these lipid proteins and oxidative enzymes were higher in endurance-trained individuals when assessed in whole muscle. MFO rate was strongly related to the proportion of type I fibers (R = 0.81, P < 0.01). The abundance of proteins involved in the regulation of IMCL storage and oxidation is highly muscle fiber type specific. The increased capacity for fat oxidation in endurance-trained individuals corresponded with increased IMCL content and elevated abundance of lipolytic and oxidative enzymes in combination with a greater proportion of type I muscle fibers.NEW & NOTEWORTHY We have utilized contemporary techniques to compare the fiber type-specific characteristics of skeletal muscle from endurance-trained athletes and untrained individuals. We show that type I muscle fibers have a coordinated upregulation of proteins controlling intramuscular lipid storage, mobilization, and oxidation. Furthermore, the enhanced capacity for intramuscular lipid storage and utilization in endurance-trained individuals is related to the increased expression of lipid regulatory proteins combined with a greater proportion of type I muscle fibers.
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Affiliation(s)
- C S Shaw
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Geelong, Victoria, Australia
| | - C Swinton
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Geelong, Victoria, Australia
| | - M G Morales-Scholz
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Geelong, Victoria, Australia
| | - N McRae
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Geelong, Victoria, Australia
| | - T Erftemeyer
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Geelong, Victoria, Australia
| | - A Aldous
- Olympic Park Sports Medicine Centre, Melbourne, Victoria, Australia
| | - R M Murphy
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia
| | - K F Howlett
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Geelong, Victoria, Australia
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7
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Hebisz R, Hebisz P, Borkowski J, Wierzbicka-Damska I, Zatoń M. Relationship Between the Skin Surface Temperature Changes During Sprint Interval Testing Protocol and the Aerobic Capacity in Well-Trained Cyclists. Physiol Res 2019; 68:981-989. [PMID: 31647289 DOI: 10.33549/physiolres.934114] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The study investigated whether changes in body surface temperature in a sprint interval testing protocol (SITP) correlated with aerobic capacity in cyclists. The study involved 21 well-trained cyclists. Maximal aerobic power and maximal oxygen uptake relative to lean body mass (LBM-P(max) and LBM-VO(2max), respectively) were determined by incremental exercise testing on a cycle ergometer. SITP was administered 48 hours later and involved four 30-s maximal sprints interspersed with 90-s active recovery. Body surface temperature was recorded at the temple and arm and the delta difference between baseline temperature and temperature measured immediately after the first sprint (DeltaTt(1) and DeltaTa(1), respectively) and 80 seconds after the fourth sprint (DeltaTt(4) and DeltaTa(4)), respectively) was calculated. Significant correlations were found between DeltaTt4 and LBM-Pmax and LBM-VO(2max) (r=0.63 and r=0.75, respectively) with no significant change in DeltaTa(1) or DeltaTa(4). Body surface temperature, measured at the temple region, can be used to indirectly assess aerobic capacity during maximal sprint exercise.
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Affiliation(s)
- R Hebisz
- Department of Physiology and Biochemistry, University School of Physical Education in Wroclaw, Poland.
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8
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Riis S, Møller AB, Dollerup O, Høffner L, Jessen N, Madsen K. Acute and sustained effects of a periodized carbohydrate intake using the sleep-low model in endurance-trained males. Scand J Med Sci Sports 2019; 29:1866-1880. [PMID: 31430404 DOI: 10.1111/sms.13541] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 08/12/2019] [Accepted: 08/15/2019] [Indexed: 12/19/2022]
Abstract
Repeated periodization of carbohydrate (CHO) intake using a diet-exercise strategy called the sleep-low model can potentially induce mitochondrial biogenesis and improve endurance performance in endurance-trained individuals. However, more studies are needed to confirm the performance-related effects and to investigate the sustained effects on maximal fat oxidation (MFO) rate and proteins involved in intramuscular lipid metabolism. Thirteen endurance-trained males (age 23-44 years; V ˙ O2 -max, 63.9 ± 4.6 mL·kg-1 ·min-1 ) were randomized into two groups: sleep-low (LOW-CHO) or high CHO availability (HIGH-CHO) in three weekly training blocks over 4 weeks. The acute metabolic response was investigated during 60 minutes of exercise within the last 3 weeks of the intervention. Pre- and post-intervention, 30-minute time-trial performance was investigated after a 90-minute pre-load, which as a novel approach included nine intense intervals (and estimation of MFO). Additionally, muscle biopsies (v. lateralis) were obtained to investigate expression of proteins involved in intramuscular lipid metabolism using Western blotting. During acute exercise, average fat oxidation rate was ~36% higher in LOW-CHO compared to HIGH-CHO (P = .03). This did not translate into sustained effects on MFO. Time-trial performance increased equally in both groups (overall time effect: P = .005). We observed no effect on intramuscular proteins involved in lipolysis (ATGL, G0S2, CGI-58, HSL) or fatty acid transport and β-oxidation (CD-36 and HAD, respectively). In conclusion, the sleep-low model did not induce sustained effects on MFO, endurance performance, or proteins involved in intramuscular lipid metabolism when compared to HIGH-CHO. Our study therefore questions the transferability of acute effects of the sleep-low model to superior sustained adaptations.
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Affiliation(s)
- Simon Riis
- Section for Sport Science, Department of Public Health, Aarhus University, Aarhus, Denmark.,Research Laboratory for Biochemical Pathology, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Andreas Buch Møller
- Research Laboratory for Biochemical Pathology, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus, Denmark
| | - Ole Dollerup
- Research Laboratory for Biochemical Pathology, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Medical Research Laboratory, Department of Clinical Medicine, Aarhus University Hospital, Denmark
| | - Line Høffner
- Section for Sport Science, Department of Public Health, Aarhus University, Aarhus, Denmark.,Research Laboratory for Biochemical Pathology, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Niels Jessen
- Research Laboratory for Biochemical Pathology, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus, Denmark.,Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Klavs Madsen
- Section for Sport Science, Department of Public Health, Aarhus University, Aarhus, Denmark.,Norwegian School of Sport Sciences, Oslo, Norway
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9
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Watt MJ, Cheng Y. Triglyceride metabolism in exercising muscle. Biochim Biophys Acta Mol Cell Biol Lipids 2017; 1862:1250-1259. [PMID: 28652193 DOI: 10.1016/j.bbalip.2017.06.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 06/15/2017] [Accepted: 06/20/2017] [Indexed: 12/21/2022]
Abstract
Triglycerides are stored within lipid droplets in skeletal muscle and can be hydrolyzed to produce fatty acids for energy production through β-oxidation and oxidative phosphorylation. While there was some controversy regarding the quantitative importance of intramyocellular triglyceride (IMTG) as a metabolic substrate, recent advances in proton magnetic resonance spectroscopy and confocal microscopy support earlier tracer and biopsy studies demonstrating a substantial contribution of IMTG to energy production, particularly during moderate-intensity endurance exercise. This review provides an update on the understanding of IMTG utilization during exercise, with a focus on describing the key regulatory proteins that control IMTG breakdown and how these proteins respond to acute exercise and in the adaptation to exercise training. This article is part of a Special Issue entitled: Recent Advances in Lipid Droplet Biology edited by Rosalind Coleman and Matthijs Hesselink.
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Affiliation(s)
- Matthew J Watt
- Metabolic Disease and Obesity program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia; Department of Physiology, Monash University, Clayton, Victoria 3800, Australia.
| | - Yunsheng Cheng
- Metabolic Disease and Obesity program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia; Department of Physiology, Monash University, Clayton, Victoria 3800, Australia
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10
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Schuldiner M, Bohnert M. A different kind of love - lipid droplet contact sites. Biochim Biophys Acta Mol Cell Biol Lipids 2017. [PMID: 28627434 DOI: 10.1016/j.bbalip.2017.06.005] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Lipid droplets (LDs) store lipids and hence serve as energy reservoir and as a source for building-blocks for the organelle membrane systems. LD biology therefore depends on tight communication with other organelles. The unique architecture of LDs, consisting of a neutral lipid core shielded by a phospholipid-monolayer, is however an obstacle to bulk-exchange of bilayer-bounded vesicles with other organelles. In recent years, it is emerging that contact sites, places where two organelles are positioned in close proximity allowing vesicle-independent communication, are an important way to integrate LDs into the organellar landscape. However, few LD contact sites have been studied in depth and our understanding of their structure, extent and function is only starting to emerge. Here, we highlight recent findings on the functions of LD contact sites and on the proteins involved in their formation and hypothesize about the unique characteristics of the contact sites formed by these intriguing organelles. This article is part of a Special Issue entitled: Recent Advances in Lipid Droplet Biology edited by Rosalind Coleman and Matthijs Hesselink.
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Affiliation(s)
- Maya Schuldiner
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Maria Bohnert
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel.
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Guadalupe-Grau A, Fernández-Elías VE, Ortega JF, Dela F, Helge JW, Mora-Rodriguez R. Effects of 6-month aerobic interval training on skeletal muscle metabolism in middle-aged metabolic syndrome patients. Scand J Med Sci Sports 2017; 28:585-595. [DOI: 10.1111/sms.12881] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/06/2017] [Indexed: 12/20/2022]
Affiliation(s)
- A. Guadalupe-Grau
- Xlab; Department of Biomedical Sciences; Faculty of Health Sciences; Center for Healthy Aging; University of Copenhagen; Copenhagen Denmark
- ImFINE Research Group; Department of Health and Human Performance; Technical University of Madrid; Madrid Spain
| | - V. E. Fernández-Elías
- Exercise Physiology Laboratory at Toledo; University of Castilla-La Mancha; Toledo Spain
- Department of Sport Science; European University of Madrid; Madrid Spain
| | - J. F. Ortega
- Exercise Physiology Laboratory at Toledo; University of Castilla-La Mancha; Toledo Spain
| | - F. Dela
- Xlab; Department of Biomedical Sciences; Faculty of Health Sciences; Center for Healthy Aging; University of Copenhagen; Copenhagen Denmark
| | - J. W. Helge
- Xlab; Department of Biomedical Sciences; Faculty of Health Sciences; Center for Healthy Aging; University of Copenhagen; Copenhagen Denmark
| | - R. Mora-Rodriguez
- Exercise Physiology Laboratory at Toledo; University of Castilla-La Mancha; Toledo Spain
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