1
|
Yu W, Yao Y, Ye N, Zhao Y, Ye Z, Wei W, Zhang L, Chen J. The myokine CCL5 recruits subcutaneous preadipocytes and promotes intramuscular fat deposition in obese mice. Am J Physiol Cell Physiol 2024; 326:C1320-C1333. [PMID: 38497114 DOI: 10.1152/ajpcell.00591.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 03/04/2024] [Accepted: 03/04/2024] [Indexed: 03/19/2024]
Abstract
Intramuscular fat (IMF) refers to the lipid stored in skeletal muscle tissue. The number and size of intramuscular adipocytes are the primary factors that regulate IMF content. Intramuscular adipocytes can be derived from either in situ or ectopic migration. In this study, it was discovered that the regulation of IMF levels is achieved through the chemokine (C-C motif) ligand 5 (CCL5)/chemokine (C-C motif) receptor 5 (CCR5) pathway by modulating adipocyte migration. In coculture experiments, C2C12 myotubes were more effective in promoting the migration of 3T3-L1 preadipocytes than C2C12 myoblasts, along with increasing CCL5. Correspondingly, overexpressing the CCR5, one of the receptors of CCL5, in 3T3-L1 preadipocytes facilitated their migration. Conversely, the application of the CCL5/CCR5 inhibitor, MARAVIROC (MVC), reduced this migration. In vivo, transplanted experiments of subcutaneous adipose tissue (SCAT) from transgenic mice expressing green fluorescent protein (GFP) provided evidence that injecting recombinant CCL5 (rCCL5) into skeletal muscle promotes the migration of subcutaneous adipocytes to the skeletal muscle. The level of CCL5 in skeletal muscle increased with obesity. Blocking the CCL5/CCR5 axis by MVC inhibited IMF deposition, whereas elevated skeletal muscle CCL5 promoted IMF deposition in obese mice. These results establish a link between the IMF and the CCL5/CCR5 pathway, which could have a potential application for modulating IMF through adipocyte migration.NEW & NOTEWORTHY C2C12 myotubes attract 3T3-L1 preadipocyte migration regulated by the chemokine (C-C motif) ligand 5 (CCL5)/ chemokine (C-C motif) receptor 5 (CCR5) axis. High levels of skeletal muscle-specific CCL5 promote the migration of subcutaneous adipocytes to skeletal muscle and induce the intramuscular fat (IMF) content.
Collapse
Affiliation(s)
- Wensai Yu
- College of Animal Science and TechnologyNanjing Agricultural University, NanjingPeople's Republic of China
| | - Yao Yao
- College of Animal Science and TechnologyNanjing Agricultural University, NanjingPeople's Republic of China
| | - Nanwei Ye
- College of Animal Science and TechnologyNanjing Agricultural University, NanjingPeople's Republic of China
| | - Yuelei Zhao
- College of Animal Science and TechnologyNanjing Agricultural University, NanjingPeople's Republic of China
| | - Zijian Ye
- College of Animal Science and TechnologyNanjing Agricultural University, NanjingPeople's Republic of China
| | - Wei Wei
- College of Animal Science and TechnologyNanjing Agricultural University, NanjingPeople's Republic of China
| | - Lifan Zhang
- College of Animal Science and TechnologyNanjing Agricultural University, NanjingPeople's Republic of China
| | - Jie Chen
- College of Animal Science and TechnologyNanjing Agricultural University, NanjingPeople's Republic of China
| |
Collapse
|
2
|
Alqallaf J, Orange ST, Matu J, Griffiths A, Johnson K, Stavropoulos-Kalinoglou A, Holliday A, Wilson O. The Effect of High-Fat Diet on Intramyocellular Lipid Content in Healthy Adults: A Systematic Review, Meta-Analysis, and Meta-Regression. J Nutr 2024; 154:1087-1100. [PMID: 38417551 PMCID: PMC11007750 DOI: 10.1016/j.tjnut.2024.02.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 02/20/2024] [Accepted: 02/23/2024] [Indexed: 03/01/2024] Open
Abstract
Fatty acids are stored within the muscle as intramyocellular lipids (IMCL). Some, but not all, studies indicate that following a high-fat diet (HFD), IMCL may accumulate and affect insulin sensitivity. This systematic review and meta-analysis aimed to quantify the effects of an HFD on IMCL. It also explored the potential modifying effects of HFD fat content and duration, IMCL measurement technique, physical activity status, and the associations of IMCL with insulin sensitivity. Five databases were systematically searched for studies that examined the effect of ≥3 d of HFD (>35% daily energy intake from fat) on IMCL content in healthy individuals. Meta-regressions were used to investigate associations of the HFD total fat content, duration, physical activity status, IMCL measurement technique, and insulin sensitivity with IMCL responses. Changes in IMCL content and insulin sensitivity (assessed by hyperinsulinemic-euglycemic clamp) are presented as standardized mean difference (SMD) using a random effects model with 95% confidence intervals (95% CIs). Nineteen studies were included in the systematic review and 16 in the meta-analysis. IMCL content increased following HFD (SMD = 0.63; 95% CI: 0.31, 0.94, P = 0.001). IMCL accumulation was not influenced by total fat content (P = 0.832) or duration (P = 0.844) of HFD, physical activity status (P = 0.192), or by the IMCL measurement technique (P > 0.05). Insulin sensitivity decreased following HFD (SMD = -0.34; 95% CI: -0.52, -0.16; P = 0.003), but this was not related to the increase in IMCL content following HFD (P = 0.233). Consumption of an HFD (>35% daily energy intake from fat) for ≥3 d significantly increases IMCL content in healthy individuals regardless of HFD total fat content and duration of physical activity status. All IMCL measurement techniques detected the increased IMCL content following HFD. The dissociation between changes in IMCL and insulin sensitivity suggests that other factors may drive HFD-induced impairments in insulin sensitivity in healthy individuals. This trial was registered at PROSPERO as CRD42021257984.
Collapse
Affiliation(s)
- Jasem Alqallaf
- Carnegie School of Sport, Leeds Beckett University, United Kingdom
| | - Samuel T Orange
- School of Biomedical, Nutritional, and Sport Sciences, Faculty of Medical Sciences, Newcastle University, United Kingdom; Newcastle University Centre for Cancer, Newcastle University, United Kingdom
| | - Jamie Matu
- School of Health, Leeds Beckett University, United Kingdom
| | - Alex Griffiths
- School of Health, Leeds Beckett University, United Kingdom
| | - Kelsie Johnson
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, United Kingdom
| | | | - Adrian Holliday
- School of Biomedical, Nutritional, and Sport Sciences, Faculty of Medical Sciences, Newcastle University, United Kingdom
| | - Oliver Wilson
- Carnegie School of Sport, Leeds Beckett University, United Kingdom.
| |
Collapse
|
3
|
Song Y, Wei D, Raza SHA, Zhao Y, Jiang C, Song X, Wu H, Wang X, Luoreng Z, Ma Y. Research progress of intramuscular fat formation based on co-culture. Anim Biotechnol 2023; 34:3216-3236. [PMID: 36200856 DOI: 10.1080/10495398.2022.2127410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
Intramuscular fat (IMF) is closely related to the meat quality of livestock and poultry. As a new cell culture technique in vitro, cell co-culture has been gradually applied to the related research of IMF formation because it can simulate the changes of microenvironment in vivo during the process of IMF cell formation. In the co-culture model, in addition to studying the effects of skeletal muscle cells on the proliferation and differentiation of IMF, we can also consider the role of many secretion factors in the formation of IMF, thus making the cell research in vitro closer to the real level in vivo. This paper reviewed the generation and origin of IMF, summarized the existing co-culture methods and systems, and discussed the advantages and disadvantages of each method as well as the challenges faced in the establishment of the system, with emphasis on the current status of research on the formation of IMF for human and animal based on co-culture technology.
Collapse
Affiliation(s)
- Yaping Song
- School of Agriculture, Ningxia University, Ningxia Yin Chuan, China
- Key Laboratory of Ruminant Molecular Cell Breeding, Ningxia University, Ningxia Yinchuan, China
| | - Dawei Wei
- School of Agriculture, Ningxia University, Ningxia Yin Chuan, China
- Key Laboratory of Ruminant Molecular Cell Breeding, Ningxia University, Ningxia Yinchuan, China
| | | | - Yiang Zhao
- School of Agriculture, Ningxia University, Ningxia Yin Chuan, China
- Key Laboratory of Ruminant Molecular Cell Breeding, Ningxia University, Ningxia Yinchuan, China
| | - Chao Jiang
- School of Agriculture, Ningxia University, Ningxia Yin Chuan, China
- Key Laboratory of Ruminant Molecular Cell Breeding, Ningxia University, Ningxia Yinchuan, China
| | - Xiaoyu Song
- School of Agriculture, Ningxia University, Ningxia Yin Chuan, China
- Key Laboratory of Ruminant Molecular Cell Breeding, Ningxia University, Ningxia Yinchuan, China
| | - Hao Wu
- School of Agriculture, Ningxia University, Ningxia Yin Chuan, China
- Key Laboratory of Ruminant Molecular Cell Breeding, Ningxia University, Ningxia Yinchuan, China
| | - Xingping Wang
- School of Agriculture, Ningxia University, Ningxia Yin Chuan, China
- Key Laboratory of Ruminant Molecular Cell Breeding, Ningxia University, Ningxia Yinchuan, China
| | - Zhuoma Luoreng
- School of Agriculture, Ningxia University, Ningxia Yin Chuan, China
- Key Laboratory of Ruminant Molecular Cell Breeding, Ningxia University, Ningxia Yinchuan, China
| | - Yun Ma
- School of Agriculture, Ningxia University, Ningxia Yin Chuan, China
- Key Laboratory of Ruminant Molecular Cell Breeding, Ningxia University, Ningxia Yinchuan, China
| |
Collapse
|
4
|
Lee YG, Woo H, Choi C, Ryoo GH, Chung YJ, Lee JH, Jung SJ, Chae SW, Bae EJ, Park BH. Supplementation with Vitis vinifera Jingzaojing Leaf and Shoot Extract Improves Exercise Endurance in Mice. Nutrients 2022; 14:nu14194033. [PMID: 36235689 PMCID: PMC9573418 DOI: 10.3390/nu14194033] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 09/24/2022] [Accepted: 09/26/2022] [Indexed: 11/16/2022] Open
Abstract
Switching myofibers from the fast-glycolytic type to the slow-oxidative type is associated with an alleviation of the symptoms associated with various cardiometabolic diseases. This study investigates the effect of Vitis vinifera Jingzaojing leaf and shoot extract (JLSE), which is rich in phenolic compounds, on the regulation of skeletal muscle fiber-type switching, as well as the associated underlying mechanism. Male C57BL/6N mice were supplemented orally with vehicle or JLSE (300 mg/kg) and subjected to treadmill exercise training. After four weeks, mice in the JLSE-supplemented group showed significantly improved exercise endurance and mitochondrial oxidative capacity. JLSE supplementation increased the expression of sirtuin 6 and decreased Sox6 expression, thereby elevating the number of mitochondria and encouraging fast-to-slow myofiber switching. The results of our experiments suggest that JLSE supplementation reprograms myofiber composition to favor the slow oxidative type, ultimately enhancing exercise endurance.
Collapse
Affiliation(s)
- Yong Gyun Lee
- School of Pharmacy, Jeonbuk National University, Jeonju 54896, Jeonbuk, Korea
| | - Hayoung Woo
- Department of Nutritional Sciences, University of Connecticut, Storrs, CT 06269, USA
| | - Chul Choi
- Department of Neurosurgery, Jeonbuk National University Medical School, Jeonju 54896, Jeonbuk, Korea
| | - Ga-Hee Ryoo
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 56212, Jeonbuk, Korea
| | - Yun-Jo Chung
- Biomedical Research Institute, Jeonbuk National University, Jeonju 54907, Jeonbuk, Korea
| | - Ju-Hyung Lee
- Department of Preventive Medicine, Jeonbuk National University Medical School, Jeonju 54896, Jeonbuk, Korea
| | - Su-Jin Jung
- Clinical Trial Center for Functional Foods, Jeonbuk National University Hospital, Jeonju 54907, Jeonbuk, Korea
| | - Soo-Wan Chae
- Clinical Trial Center for Functional Foods, Jeonbuk National University Hospital, Jeonju 54907, Jeonbuk, Korea
| | - Eun Ju Bae
- School of Pharmacy, Jeonbuk National University, Jeonju 54896, Jeonbuk, Korea
- Correspondence: (E.J.B.); (B.-H.P.)
| | - Byung-Hyun Park
- Department of Biochemistry and Research Institute for Endocrine Sciences, Jeonbuk National University Medical School, Jeonju 54896, Jeonbuk, Korea
- Correspondence: (E.J.B.); (B.-H.P.)
| |
Collapse
|
5
|
Barrett JS, Whytock KL, Strauss JA, Wagenmakers AJM, Shepherd SO. High intramuscular triglyceride turnover rates and the link to insulin sensitivity: influence of obesity, type 2 diabetes and physical activity. Appl Physiol Nutr Metab 2022; 47:343-356. [PMID: 35061523 DOI: 10.1139/apnm-2021-0631] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Large intramuscular triglyceride (IMTG) stores in sedentary, obese individuals have been linked to insulin resistance, yet well-trained athletes exhibit high IMTG levels whilst maintaining insulin sensitivity. Contrary to previous assumptions, it is now known that IMTG content per se does not result in insulin resistance. Rather, insulin resistance is caused, at least in part, by the presence of high concentrations of harmful lipid metabolites, such as diacylglycerols and ceramides in muscle. Several mechanistic differences between obese sedentary individuals and their highly trained counterparts have been identified, which determine the differential capacity for IMTG synthesis and breakdown in these populations. In this review, we first describe the most up-to-date mechanisms by which a low IMTG turnover rate (both breakdown and synthesis) leads to the accumulation of lipid metabolites and results in skeletal muscle insulin resistance. We then explore current and potential exercise and nutritional strategies that target IMTG turnover in sedentary obese individuals, to improve insulin sensitivity. Overall, improving IMTG turnover should be an important component of successful interventions that aim to prevent the development of insulin resistance in the ever-expanding sedentary, overweight and obese populations. Novelty: A description of the most up-to-date mechanisms regulating turnover of the IMTG pool. An exploration of current and potential exercise/nutritional strategies to target and enhance IMTG turnover in obese individuals. Overall, highlights the importance of improving IMTG turnover to prevent the development of insulin resistance.
Collapse
Affiliation(s)
- J S Barrett
- Research Institute for Sport & Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - K L Whytock
- Translational Research Institute, AdventHealth, Orlando, FL 32804, USA
| | - J A Strauss
- Research Institute for Sport & Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - A J M Wagenmakers
- Research Institute for Sport & Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - S O Shepherd
- Research Institute for Sport & Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| |
Collapse
|
6
|
Taatjes DJ, Roth J. In focus in HCB. Histochem Cell Biol 2021; 154:347-354. [PMID: 32984928 DOI: 10.1007/s00418-020-01921-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Douglas J Taatjes
- Department of Pathology and Laboratory Medicine, Larner College of Medicine, University of Vermont, Burlington, VT, 05405, USA.
| | - Jürgen Roth
- University of Zurich, 8091, Zurich, Switzerland
| |
Collapse
|
7
|
Turner MC, Rimington RP, Martin NRW, Fleming JW, Capel AJ, Hodson L, Lewis MP. Physiological and pathophysiological concentrations of fatty acids induce lipid droplet accumulation and impair functional performance of tissue engineered skeletal muscle. J Cell Physiol 2021; 236:7033-7044. [PMID: 33738797 DOI: 10.1002/jcp.30365] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 02/11/2021] [Accepted: 03/08/2021] [Indexed: 12/19/2022]
Abstract
Fatty acids (FA) exert physiological and pathophysiological effects leading to changes in skeletal muscle metabolism and function, however, in vitro models to investigate these changes are limited. These experiments sought to establish the effects of physiological and pathophysiological concentrations of exogenous FA upon the function of tissue engineered skeletal muscle (TESkM). Cultured initially for 14 days, C2C12 TESkM was exposed to FA-free bovine serum albumin alone or conjugated to a FA mixture (oleic, palmitic, linoleic, and α-linoleic acids [OPLA] [ratio 45:30:24:1%]) at different concentrations (200 or 800 µM) for an additional 4 days. Subsequently, TESkM morphology, functional capacity, gene expression and insulin signaling were analyzed. There was a dose response increase in the number and size of lipid droplets within the TESkM (p < .05). Exposure to exogenous FA increased the messenger RNA expression of genes involved in lipid storage (perilipin 2 [p < .05]) and metabolism (pyruvate dehydrogenase lipoamide kinase isozyme 4 [p < .01]) in a dose dependent manner. TESkM force production was reduced (tetanic and single twitch) (p < .05) and increases in transcription of type I slow twitch fiber isoform, myosin heavy chain 7, were observed when cultured with 200 µM OPLA compared to control (p < .01). Four days of OPLA exposure results in lipid accumulation in TESkM which in turn results in changes in muscle function and metabolism; thus, providing insight ito the functional and mechanistic changes of TESkM in response to exogenous FA.
Collapse
Affiliation(s)
- Mark C Turner
- School of Sport, Exercise and Health Sciences, National Centre for Sport and Exercise Medicine, Loughborough University, Loughborough, UK.,Leicester Biomedical Research Centre, University Hospitals of Leicester NHS Trust, Leicester, UK.,Centre for Sport, Exercise and Life Sciences, Research Institute for Health and Wellbeing, Coventry University, Coventry, UK
| | - Rowan P Rimington
- School of Sport, Exercise and Health Sciences, National Centre for Sport and Exercise Medicine, Loughborough University, Loughborough, UK
| | - Neil R W Martin
- School of Sport, Exercise and Health Sciences, National Centre for Sport and Exercise Medicine, Loughborough University, Loughborough, UK
| | - Jacob W Fleming
- School of Sport, Exercise and Health Sciences, National Centre for Sport and Exercise Medicine, Loughborough University, Loughborough, UK
| | - Andrew J Capel
- School of Sport, Exercise and Health Sciences, National Centre for Sport and Exercise Medicine, Loughborough University, Loughborough, UK
| | - Leanne Hodson
- Oxford Center for Diabetes, Endocrinology and Metabolism, Oxford Biomedical Research Centre, Radcliffe Department of Medicine, Churchill Hospital, University of Oxford, Oxford, UK
| | - Mark P Lewis
- School of Sport, Exercise and Health Sciences, National Centre for Sport and Exercise Medicine, Loughborough University, Loughborough, UK
| |
Collapse
|
8
|
Whytock KL, Shepherd SO, Cocks M, Wagenmakers AJM, Strauss JA. Young, healthy males and females present cardiometabolic protection against the detrimental effects of a 7-day high-fat high-calorie diet. Eur J Nutr 2020; 60:1605-1617. [PMID: 32789769 PMCID: PMC7987629 DOI: 10.1007/s00394-020-02357-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 08/03/2020] [Indexed: 01/19/2023]
Abstract
PURPOSE High-fat, high-calorie (HFHC) diets have been used as a model to investigate lipid-induced insulin resistance. Short-term HFHC diets reduce insulin sensitivity in young healthy males, but to date, no study has directly compared males and females to elucidate sex-specific differences in the effects of a HFHC diet on functional metabolic and cardiovascular outcomes. METHODS Eleven males (24 ± 4 years; BMI 23 ± 2 kg.m-2; V̇O2 peak 62.3 ± 8.7 ml.min-1.kg-1FFM) were matched to 10 females (25 ± 4 years; BMI 23 ± 2 kg.m-2; V̇O2 peak 58.2 ± 8.2 ml.min-1.kg-1FFM). Insulin sensitivity, measured via oral glucose tolerance test, metabolic flexibility, arterial stiffness, body composition and blood lipids and liver enzymes were measured before and after 7 days of a high-fat (65% energy) high-calorie (+ 50% kcal) diet. RESULTS The HFHC diet did not change measures of insulin sensitivity, metabolic flexibility or arterial stiffness in either sex. There was a trend towards increased total body fat mass (kg) after the HFHC diet (+ 1.8% and + 2.3% for males and females, respectively; P = 0.056). In contrast to females, males had a significant increase in trunk to leg fat mass ratio (+ 5.1%; P = 0.005). CONCLUSION Lean, healthy young males and females appear to be protected from the negative cardio-metabolic effects of a 7-day HFHC diet. Future research should use a prolonged positive energy balance achieved via increased energy intake and reduced energy expenditure to exacerbate negative metabolic and cardiovascular functional outcomes to determine whether sex-specific differences exist under more metabolically challenging conditions.
Collapse
Affiliation(s)
- Katie L Whytock
- Research Institute of Sport and Exercise Science, Liverpool John Moores University, Liverpool, UK
| | - Sam O Shepherd
- Research Institute of Sport and Exercise Science, Liverpool John Moores University, Liverpool, UK
| | - Matt Cocks
- Research Institute of Sport and Exercise Science, Liverpool John Moores University, Liverpool, UK
| | - Anton J M Wagenmakers
- Research Institute of Sport and Exercise Science, Liverpool John Moores University, Liverpool, UK
| | - Juliette A Strauss
- Research Institute of Sport and Exercise Science, Liverpool John Moores University, Liverpool, UK.
| |
Collapse
|
9
|
Strauss JA, Shepherd DA, Macey M, Jevons EFP, Shepherd SO. Divergence exists in the subcellular distribution of intramuscular triglyceride in human skeletal muscle dependent on the choice of lipid dye. Histochem Cell Biol 2020; 154:369-382. [PMID: 32627050 PMCID: PMC7532971 DOI: 10.1007/s00418-020-01898-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/27/2020] [Indexed: 01/19/2023]
Abstract
Despite over 50 years of research, a comprehensive understanding of how intramuscular triglyceride (IMTG) is stored in skeletal muscle and its contribution as a fuel during exercise is lacking. Immunohistochemical techniques provide information on IMTG content and lipid droplet (LD) morphology on a fibre type and subcellular-specific basis, and the lipid dye Oil Red O (ORO) is commonly used to achieve this. BODIPY 493/503 (BODIPY) is an alternative lipid dye with lower background staining and narrower emission spectra. Here we provide the first quantitative comparison of BODIPY and ORO for investigating exercise-induced changes in IMTG content and LD morphology on a fibre type and subcellular-specific basis. Estimates of IMTG content were greater when using BODIPY, which was predominantly due to BODIPY detecting a larger number of LDs, compared to ORO. The subcellular distribution of intramuscular lipid was also dependent on the lipid dye used; ORO detects a greater proportion of IMTG in the periphery (5 μm below cell membrane) of the fibre, whereas IMTG content was higher in the central region using BODIPY. In response to 60 min moderate-intensity cycling exercise, IMTG content was reduced in both the peripheral (− 24%) and central region (− 29%) of type I fibres (P < 0.05) using BODIPY, whereas using ORO, IMTG content was only reduced in the peripheral region of type I fibres (− 31%; P < 0.05). As well as highlighting some methodological considerations herein, our investigation demonstrates that important differences exist between BODIPY and ORO for detecting and quantifying IMTG on a fibre type and subcellular-specific basis.
Collapse
Affiliation(s)
- Juliette A Strauss
- Research Institute for Sport and Exercise Science, Liverpool John Moores University, Liverpool, L3 3AF, UK.
| | - Daisy A Shepherd
- Clinical Epidemiology and Biostatistics Unit, Murdoch Children's Research Institute, Royal Children's Hospital, Victoria, 3052, Australia.,Department of Paediatrics, The University of Melbourne, Victoria, 3010, Australia
| | - Myfanwy Macey
- Research Institute for Sport and Exercise Science, Liverpool John Moores University, Liverpool, L3 3AF, UK
| | - Emily F P Jevons
- Research Institute for Sport and Exercise Science, Liverpool John Moores University, Liverpool, L3 3AF, UK
| | - Sam O Shepherd
- Research Institute for Sport and Exercise Science, Liverpool John Moores University, Liverpool, L3 3AF, UK
| |
Collapse
|
10
|
Chow LS, Mashek DG. The microenvironment matters: the secret life of intramuscular lipid droplets. J Physiol 2020; 598:1117-1118. [PMID: 32052866 DOI: 10.1113/jp279583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Lisa S Chow
- Division of Diabetes, Endocrinology and Metabolism, University of Minnesota, Minneapolis, MN, USA
| | - Douglas G Mashek
- Division of Diabetes, Endocrinology and Metabolism, University of Minnesota, Minneapolis, MN, USA.,Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA
| |
Collapse
|