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Lynch CE, Brandt AR, Vincenty CS, Robbins E, Skiles C, Minchev K, Chambers TL, Belangee A, Trappe TA, Trappe SW. Adipose biopsy techniques for studies in human exercise physiology. Am J Physiol Regul Integr Comp Physiol 2024; 326:R220-R229. [PMID: 38223939 DOI: 10.1152/ajpregu.00266.2023] [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: 11/28/2023] [Revised: 01/05/2024] [Accepted: 01/05/2024] [Indexed: 01/16/2024]
Abstract
Adipose biopsy techniques are relatively undefined for exercise physiology research in individuals at or near normal weight. The purpose of this study was to compare the influence of two adipose biopsy techniques on tissue quality through measurements of adipocyte cell size, as well as mRNA and protein levels of select pro- and anti-inflammatory cytokines and adipokines. Thirteen participants (9 M, 4 W; 28 ± 4 yr; 27 ± 3 kg·m-2; V̇o2max: 3.3 ± 0.7 L·min-1) underwent subcutaneous adipose biopsies on either side of the umbilicus (incision: ∼8 cm lateral, sampling area: ∼5 cm lateral) using 1) a 6-mm Bergström biopsy needle and 2) a mini-liposuction approach with a 4-mm Mercedes biopsy needle that used prebiopsy tumescent delivery (∼30 mL 0.9% NaCl solution) into the sampling area (i.e., 'wet' technique). Tissue obtained was processed identically for analysis and both techniques returned high-quality tissue for histology (similar % intact adipocytes), mRNA (RNA integrity numbers >7.0), and protein. Adipocyte size was similar (P > 0.05) between both techniques (Bergström: 6,116 ± 1,652 μm2, 554-23,522 µm2; Mercedes: 6,517 ± 952 μm2, 926-21,969 µm2). There were also no differences (P > 0.05) between the two techniques for the measured cytokines (pro- and anti-inflammatory) and adipokines at the mRNA and protein levels. Adipocyte size was positively correlated with body mass index and body fat percentage, and negatively correlated with V̇o2max (P < 0.05). These results suggest both adipose biopsy techniques used in the current investigation are appropriate for histological, transcriptional, and translational level measurements in exercise physiology studies of nonobese women and men.NEW & NOTEWORTHY This study provides investigators with useful information related to adipose biopsy sampling approaches that can be used when planning studies that use measurements of adipose histology, as well as measurements at the mRNA and protein level. Adipose periumbilical sampling with the Bergström biopsy needle and the Mercedes wet mini-liposuction technique are both appropriate options for studies in exercise physiology and in nonobese individuals.
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Affiliation(s)
- Colleen E Lynch
- Human Performance Laboratory, Ball State University, Muncie, Indiana, United States
| | - Anna R Brandt
- Human Performance Laboratory, Ball State University, Muncie, Indiana, United States
| | - Caroline S Vincenty
- Human Performance Laboratory, Ball State University, Muncie, Indiana, United States
| | - Ethan Robbins
- Human Performance Laboratory, Ball State University, Muncie, Indiana, United States
| | - Chad Skiles
- Human Performance Laboratory, Ball State University, Muncie, Indiana, United States
| | - Kiril Minchev
- Human Performance Laboratory, Ball State University, Muncie, Indiana, United States
| | - Toby L Chambers
- Human Performance Laboratory, Ball State University, Muncie, Indiana, United States
| | - Alicia Belangee
- Human Performance Laboratory, Ball State University, Muncie, Indiana, United States
| | - Todd A Trappe
- Human Performance Laboratory, Ball State University, Muncie, Indiana, United States
| | - Scott W Trappe
- Human Performance Laboratory, Ball State University, Muncie, Indiana, United States
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2
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Ashcroft SP, Stocks B, Egan B, Zierath JR. Exercise induces tissue-specific adaptations to enhance cardiometabolic health. Cell Metab 2024; 36:278-300. [PMID: 38183980 DOI: 10.1016/j.cmet.2023.12.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 10/06/2023] [Accepted: 12/05/2023] [Indexed: 01/08/2024]
Abstract
The risk associated with multiple cancers, cardiovascular disease, diabetes, and all-cause mortality is decreased in individuals who meet the current recommendations for physical activity. Therefore, regular exercise remains a cornerstone in the prevention and treatment of non-communicable diseases. An acute bout of exercise results in the coordinated interaction between multiple tissues to meet the increased energy demand of exercise. Over time, the associated metabolic stress of each individual exercise bout provides the basis for long-term adaptations across tissues, including the cardiovascular system, skeletal muscle, adipose tissue, liver, pancreas, gut, and brain. Therefore, regular exercise is associated with a plethora of benefits throughout the whole body, including improved cardiorespiratory fitness, physical function, and glycemic control. Overall, we summarize the exercise-induced adaptations that occur within multiple tissues and how they converge to ultimately improve cardiometabolic health.
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Affiliation(s)
- Stephen P Ashcroft
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ben Stocks
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Brendan Egan
- School of Health and Human Performance, Dublin City University, Dublin, Ireland
| | - Juleen R Zierath
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Integrative Physiology, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; Integrative Physiology, Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
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3
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Pitzer CR, Paez HG, Ferrandi PJ, Mohamed J, Alway SE. Extracellular vesicles from obese and diabetic mouse plasma alter C2C12 myotube glucose uptake and gene expression. Physiol Rep 2024; 12:e15898. [PMID: 38169108 PMCID: PMC10761623 DOI: 10.14814/phy2.15898] [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: 06/29/2023] [Revised: 10/07/2023] [Accepted: 11/20/2023] [Indexed: 01/05/2024] Open
Abstract
Recent studies have indicated a role for circulating extracellular vesicles (EVs) in the pathogenesis of multiple diseases. However, most in vitro studies have used variable and arbitrary doses of EVs rather than interpreting EVs as an existing component of standard skeletal muscle cell culture media. The current study provides an initial investigation into the effects of circulating EVs on the metabolic phenotype of C2C12 myotubes by replacing EVs from fetal bovine serum with circulating EVs from control mice or mice with obesity and type 2 diabetes (OT2D). We report that EVs associated with OT2D decrease 2-NBDG uptake (a proxy measure of glucose uptake) in the insulin-stimulated state compared to controls. OT2D associated EV treatment also significantly decreased myosin heavy chain type 1 (MHCI) mRNA abundance in myotubes but had no effect on mRNA expression of any other myosin heavy chain isoforms. OT2D-associated circulating EVs also significantly increased lipid accumulation within myotubes without altering the expression of a selection of genes important for lipid entry, synthesis, or catabolism. The data indicate that, in a severely diabetic state, circulating EVs may contribute to insulin resistance and alter gene expression in myotubes in a manner consistent with the skeletal muscle phenotype observed in OT2D.
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Affiliation(s)
- Christopher R. Pitzer
- Center for Muscle, Metabolism and Neuropathology, Division of Regenerative and Rehabilitation Sciences, College of Health ProfessionsThe University of Tennessee Health Science CenterMemphisTennesseeUSA
- Department of Physiology, College of MedicineThe University of Tennessee Health Science CenterMemphisTennesseeUSA
- Integrated Biomedical Sciences Graduate Program, College of Graduate Health SciencesThe University of Tennessee Health Science CenterMemphisTennesseeUSA
- Laboratory of Muscle Biology and Sarcopenia, Department of Physical Therapy, College of Health ProfessionsThe University of Tennessee Health Science CenterMemphisTennesseeUSA
| | - Hector G. Paez
- Center for Muscle, Metabolism and Neuropathology, Division of Regenerative and Rehabilitation Sciences, College of Health ProfessionsThe University of Tennessee Health Science CenterMemphisTennesseeUSA
- Department of Physiology, College of MedicineThe University of Tennessee Health Science CenterMemphisTennesseeUSA
- Integrated Biomedical Sciences Graduate Program, College of Graduate Health SciencesThe University of Tennessee Health Science CenterMemphisTennesseeUSA
- Laboratory of Muscle Biology and Sarcopenia, Department of Physical Therapy, College of Health ProfessionsThe University of Tennessee Health Science CenterMemphisTennesseeUSA
| | - Peter J. Ferrandi
- Center for Muscle, Metabolism and Neuropathology, Division of Regenerative and Rehabilitation Sciences, College of Health ProfessionsThe University of Tennessee Health Science CenterMemphisTennesseeUSA
- Integrated Biomedical Sciences Graduate Program, College of Graduate Health SciencesThe University of Tennessee Health Science CenterMemphisTennesseeUSA
- Laboratory of Muscle and Nerve, Department of Diagnostic and Health Sciences, College of Health ProfessionsThe University of Tennessee Health Science CenterMemphisTennesseeUSA
| | - Junaith S. Mohamed
- Center for Muscle, Metabolism and Neuropathology, Division of Regenerative and Rehabilitation Sciences, College of Health ProfessionsThe University of Tennessee Health Science CenterMemphisTennesseeUSA
- Laboratory of Muscle and Nerve, Department of Diagnostic and Health Sciences, College of Health ProfessionsThe University of Tennessee Health Science CenterMemphisTennesseeUSA
- Tennessee Institute of Regenerative MedicineThe University of Tennessee Health Science CenterMemphisTennesseeUSA
| | - Stephen E. Alway
- Center for Muscle, Metabolism and Neuropathology, Division of Regenerative and Rehabilitation Sciences, College of Health ProfessionsThe University of Tennessee Health Science CenterMemphisTennesseeUSA
- Department of Physiology, College of MedicineThe University of Tennessee Health Science CenterMemphisTennesseeUSA
- Laboratory of Muscle Biology and Sarcopenia, Department of Physical Therapy, College of Health ProfessionsThe University of Tennessee Health Science CenterMemphisTennesseeUSA
- Tennessee Institute of Regenerative MedicineThe University of Tennessee Health Science CenterMemphisTennesseeUSA
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4
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Lilja M, Moberg M, Apró W, Martínez-Aranda LM, Rundqvist H, Langlet B, Gustafsson T, Lundberg TR. Limited effect of over-the-counter doses of ibuprofen on mechanisms regulating muscle hypertrophy during resistance training in young adults. J Appl Physiol (1985) 2023; 134:753-765. [PMID: 36794689 DOI: 10.1152/japplphysiol.00698.2022] [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: 02/17/2023] Open
Abstract
We have previously shown that maximal over-the-counter doses of ibuprofen, compared with low doses of acetylsalicylic acid, reduce muscle hypertrophy in young individuals after 8 wk of resistance training. Because the mechanism behind this effect has not been fully elucidated, we here investigated skeletal muscle molecular responses and myofiber adaptations in response to acute and chronic resistance training with concomitant drug intake. Thirty-one young (aged 18-35 yr) healthy men (n = 17) and women (n = 14) were randomized to receive either ibuprofen (IBU; 1,200 mg daily; n = 15) or acetylsalicylic acid (ASA; 75 mg daily; n = 16) while undergoing 8 wk of knee extension training. Muscle biopsies from the vastus lateralis were obtained before, at week 4 after an acute exercise session, and after 8 wk of resistance training and analyzed for mRNA markers and mTOR signaling, as well as quantification of total RNA content (marker of ribosome biogenesis) and immunohistochemical analysis of muscle fiber size, satellite cell content, myonuclear accretion, and capillarization. There were only two treatment × time interaction in selected molecular markers after acute exercise (atrogin-1 and MuRF1 mRNA), but several exercise effects. Muscle fiber size, satellite cell and myonuclear accretion, and capillarization were not affected by chronic training or drug intake. RNA content increased comparably (∼14%) in both groups. Collectively, these data suggest that established acute and chronic hypertrophy regulators (including mTOR signaling, ribosome biogenesis, satellite cell content, myonuclear accretion, and angiogenesis) were not differentially affected between groups and therefore do not explain the deleterious effects of ibuprofen on muscle hypertrophy in young adults.NEW & NOTEWORTHY Here we show that mTOR signaling, fiber size, ribosome biogenesis, satellite cell content, myonuclear accretion, and angiogenesis were not differentially affected between groups undergoing 8 wk of resistance training with concomitant anti-inflammatory medication (ibuprofen versus low-dose aspirin). Atrogin-1 and MuRF-1 mRNA were more downregulated after acute exercise in the low-dose aspirin group than in the ibuprofen group. Taken together it appears that these established hypertrophy regulators do not explain the previously reported deleterious effects of high doses of ibuprofen on muscle hypertrophy in young adults.
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Affiliation(s)
- Mats Lilja
- Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden.,Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden
| | - Marcus Moberg
- Department of Physiology, Nutrition and Biomechanics, Swedish School of Sport and Health Sciences, Stockholm, Sweden
| | - William Apró
- Department of Physiology, Nutrition and Biomechanics, Swedish School of Sport and Health Sciences, Stockholm, Sweden
| | - Luis Manuel Martínez-Aranda
- Movement Analysis Laboratory for Sport and Health (MALab), Faculty of Sport, Catholic University of Murcia, Murcia, Spain
| | - Håkan Rundqvist
- Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden.,Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden
| | - Billy Langlet
- Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Thomas Gustafsson
- Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden.,Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden
| | - Tommy R Lundberg
- Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden.,Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden
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5
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Ludzki AC, Krueger EM, Gillen JB, Taylor NM, Middlebrook DO, Baldwin TC, Karabetsos KC, Schleh MW, Horowitz JF. One week of overeating upregulates angiogenic and lipolytic gene expression in human subcutaneous adipose tissue from exercise trained and untrained adults. Appl Physiol Nutr Metab 2022; 47:992-1004. [PMID: 35816737 PMCID: PMC10127504 DOI: 10.1139/apnm-2022-0078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Effective storage of excess energy in abdominal subcutaneous adipose tissue during periods of overeating may help attenuate weight-gain-related insulin resistance. The objective of this study was to assess changes in the expression of factors regulating abdominal subcutaneous adipose tissue storage capacity in response to a brief exposure to overeating in nonobese adults. Because exercise can alter the expression of genes involved in regulating adipose tissue storage capacity, we compared the responses to overeating in regular exercisers (EX, n = 11) and nonexercisers (nonEX, n = 11). Abdominal subcutaneous adipose tissue samples and oral glucose tolerance tests were performed before and after participants ate 30% above their estimated daily energy requirements for 1 week. Both EX and nonEX gained ∼1 kg (P < 0.01), and Matsuda insulin sensitivity index was reduced ∼15% (P = 0.04) in both groups. Gene expression of factors involved in lipid metabolism (HSL, ATGL, DGAT, and PPARγ) and angiogenesis (HIF1α and KDR) were increased (P < 0.05), with no differences observed between EX and nonEX. In contrast, protein abundance of these factors did not change. The modest overeating stimulus did not increase markers of inflammation in the systemic circulation or adipose tissue. Overall, our findings indicate that a brief and modest overeating stimulus can impair insulin sensitivity and upregulate genes involved in abdominal adipose tissue storage capacity similarly in exercisers and nonexercisers. ClinicalTrials.gov ID#: NCT02701738.
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Affiliation(s)
- Alison C Ludzki
- School of Kinesiology, University of Michigan, Ann Arbor, MI, USA
| | - Emily M Krueger
- School of Kinesiology, University of Michigan, Ann Arbor, MI, USA
| | - Jenna B Gillen
- School of Kinesiology, University of Michigan, Ann Arbor, MI, USA
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | - Natalie M Taylor
- School of Kinesiology, University of Michigan, Ann Arbor, MI, USA
| | | | - Toree C Baldwin
- School of Kinesiology, University of Michigan, Ann Arbor, MI, USA
| | | | - Michael W Schleh
- School of Kinesiology, University of Michigan, Ann Arbor, MI, USA
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6
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Meister BM, Hong SG, Shin J, Rath M, Sayoc J, Park JY. Healthy versus Unhealthy Adipose Tissue Expansion: the Role of Exercise. J Obes Metab Syndr 2022; 31:37-50. [PMID: 35283364 PMCID: PMC8987461 DOI: 10.7570/jomes21096] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 12/29/2021] [Accepted: 12/30/2021] [Indexed: 12/14/2022] Open
Abstract
Although the hallmark of obesity is the expansion of adipose tissue, not all adipose tissue expansion is the same. Expansion of healthy adipose tissue is accompanied by adequate capillary angiogenesis and mitochondria-centered metabolic integrity, whereas expansion of unhealthy adipose tissue is associated with capillary and mitochondrial derangement, resulting in deposition of immune cells (M1-stage macrophages) and excess production of pro-inflammatory cytokines. Accumulation of these dysfunctional adipose tissues has been linked to the development of obesity comorbidities, such as type 2 diabetes, hypertension, dyslipidemia, and cardiovascular disease, which are leading causes of human mortality and morbidity in modern society. Mechanistically, vascular rarefaction and mitochondrial incompetency (for example, low mitochondrial content, fragmented mitochondria, defective mitochondrial respiratory function, and excess production of mitochondrial reactive oxygen species) are frequently observed in adipose tissue of obese patients. Recent studies have demonstrated that exercise is a potent behavioral intervention for preventing and reducing obesity and other metabolic diseases. However, our understanding of potential cellular mechanisms of exercise, which promote healthy adipose tissue expansion, is at the beginning stage. In this review, we hypothesize that exercise can induce unique physiological stimuli that can alter angiogenesis and mitochondrial remodeling in adipose tissues and ultimately promote the development and progression of healthy adipogenesis. We summarize recent reports on how regular exercise can impose differential processes that lead to the formation of either healthy or unhealthy adipose tissue and discuss key knowledge gaps that warrant future research.
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Affiliation(s)
- Benjamin M Meister
- Department of Kinesiology, College of Public Health and Cardiovascular Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Soon-Gook Hong
- Department of Kinesiology, College of Public Health and Cardiovascular Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Junchul Shin
- Department of Kinesiology, College of Public Health and Cardiovascular Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Meghan Rath
- Department of Kinesiology, College of Public Health and Cardiovascular Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Jacqueline Sayoc
- Department of Kinesiology, College of Public Health and Cardiovascular Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Joon-Young Park
- Department of Kinesiology, College of Public Health and Cardiovascular Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
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7
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Araujo N, Sledziona J, Noothi SK, Burikhanov R, Hebbar N, Ganguly S, Shrestha-Bhattarai T, Zhu B, Katz WS, Zhang Y, Taylor BS, Liu J, Chen L, Weiss HL, He D, Wang C, Morris AJ, Cassis LA, Nikolova-Karakashian M, Nagareddy PR, Melander O, Evers BM, Kern PA, Rangnekar VM. Tumor Suppressor Par-4 Regulates Complement Factor C3 and Obesity. Front Oncol 2022; 12:860446. [PMID: 35425699 PMCID: PMC9004617 DOI: 10.3389/fonc.2022.860446] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Accepted: 02/28/2022] [Indexed: 11/30/2022] Open
Abstract
Prostate apoptosis response-4 (Par-4) is a tumor suppressor that induces apoptosis in cancer cells. However, the physiological function of Par-4 remains unknown. Here we show that conventional Par-4 knockout (Par-4-/-) mice and adipocyte-specific Par-4 knockout (AKO) mice, but not hepatocyte-specific Par-4 knockout mice, are obese with standard chow diet. Par-4-/- and AKO mice exhibit increased absorption and storage of fat in adipocytes. Mechanistically, Par-4 loss is associated with mdm2 downregulation and activation of p53. We identified complement factor c3 as a p53-regulated gene linked to fat storage in adipocytes. Par-4 re-expression in adipocytes or c3 deletion reversed the obese mouse phenotype. Moreover, obese human subjects showed lower expression of Par-4 relative to lean subjects, and in longitudinal studies, low baseline Par-4 levels denoted an increased risk of developing obesity later in life. These findings indicate that Par-4 suppresses p53 and its target c3 to regulate obesity.
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Affiliation(s)
- Nathalia Araujo
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY, United States
| | - James Sledziona
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY, United States
| | - Sunil K. Noothi
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky, Lexington, KY, United States
| | - Ravshan Burikhanov
- Department of Radiation Medicine, University of Kentucky, Lexington, KY, United States
| | - Nikhil Hebbar
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY, United States
| | - Saptadwipa Ganguly
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY, United States
| | - Tripti Shrestha-Bhattarai
- Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY, United States
| | - Beibei Zhu
- Division of Internal Medicine, University of Kentucky, Lexington, KY, United States
- Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, United States
| | - Wendy S. Katz
- Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, United States
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY, United States
| | - Yi Zhang
- Department of Computer Science, University of Kentucky, Lexington, KY, United States
| | - Barry S. Taylor
- Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY, United States
| | - Jinze Liu
- Department of Computer Science, University of Kentucky, Lexington, KY, United States
| | - Li Chen
- Division of Internal Medicine, University of Kentucky, Lexington, KY, United States
- Markey Cancer Center, University of Kentucky, Lexington, KY, United States
| | - Heidi L. Weiss
- Division of Internal Medicine, University of Kentucky, Lexington, KY, United States
- Markey Cancer Center, University of Kentucky, Lexington, KY, United States
| | - Daheng He
- Department of Statistics, University of Kentucky, Lexington, KY, United States
| | - Chi Wang
- Markey Cancer Center, University of Kentucky, Lexington, KY, United States
- Department of Biostatistics, University of Kentucky, Lexington, KY, United States
| | - Andrew J. Morris
- Division of Internal Medicine, University of Kentucky, Lexington, KY, United States
- Markey Cancer Center, University of Kentucky, Lexington, KY, United States
| | - Lisa A. Cassis
- Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, United States
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY, United States
| | - Mariana Nikolova-Karakashian
- Markey Cancer Center, University of Kentucky, Lexington, KY, United States
- Department of Physiology, University of Kentucky, Lexington, KY, United States
| | | | - Olle Melander
- Department of Clinical Sciences, Lund University, Malmö, Sweden
- Department of Internal Medicine, Skåne University Hospital, Malmö, Sweden
| | - B. Mark Evers
- Markey Cancer Center, University of Kentucky, Lexington, KY, United States
- Department of Surgery, University of Kentucky, Lexington, KY, United States
| | - Philip A. Kern
- Division of Internal Medicine, University of Kentucky, Lexington, KY, United States
- Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, United States
| | - Vivek M. Rangnekar
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY, United States
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky, Lexington, KY, United States
- Department of Radiation Medicine, University of Kentucky, Lexington, KY, United States
- Markey Cancer Center, University of Kentucky, Lexington, KY, United States
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8
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Ahn C, Ryan BJ, Schleh MW, Varshney P, Ludzki AC, Gillen JB, Van Pelt DW, Pitchford LM, Howton SM, Rode T, Hummel SL, Burant CF, Little JP, Horowitz JF. Exercise training remodels subcutaneous adipose tissue in adults with obesity even without weight loss. J Physiol 2022; 600:2127-2146. [PMID: 35249225 PMCID: PMC9058215 DOI: 10.1113/jp282371] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 03/01/2022] [Indexed: 11/08/2022] Open
Abstract
Excessive adipose tissue mass underlies much of the metabolic health complications in obesity. Although exercise training is known to improve metabolic health in individuals with obesity, the effects of exercise training without weight loss on adipose tissue structure and metabolic function remain unclear. Thirty-six adults with obesity (body mass index = 33 ± 3 kg · m-2 ) were assigned to 12 weeks (4 days week-1 ) of either moderate-intensity continuous training (MICT; 70% maximal heart rate, 45 min; n = 17) or high-intensity interval training (HIIT; 90% maximal heart rate, 10 × 1 min; n = 19), maintaining their body weight throughout. Abdominal subcutaneous adipose tissue (aSAT) biopsy samples were collected once before and twice after training (1 day after last exercise and again 4 days later). Exercise training modified aSAT morphology (i.e. reduced fat cell size, increased collagen type 5a3, both P ≤ 0.05, increased capillary density, P = 0.05) and altered protein abundance of factors that regulate aSAT remodelling (i.e. reduced matrix metallopeptidase 9; P = 0.02; increased angiopoietin-2; P < 0.01). Exercise training also increased protein abundance of factors that regulate lipid metabolism (e.g. hormone sensitive lipase and fatty acid translocase; P ≤ 0.03) and key proteins involved in the mitogen-activated protein kinase pathway when measured the day after the last exercise session. However, most of these exercise-mediated changes were no longer significant 4 days after exercise. Importantly, MICT and HIIT induced remarkably similar adaptations in aSAT. Collectively, even in the absence of weight loss, 12 weeks of exercise training induced changes in aSAT structure, as well as factors that regulate metabolism and the inflammatory signal pathway in adults with obesity. KEY POINTS: Exercise training is well-known to improve metabolic health in obesity, although how exercise modifies the structure and metabolic function of adipose tissue, in the absence of weight loss, remains unclear. We report that both 12 weeks of moderate-intensity continuous training (MICT) and 12 weeks of high-intensity interval training (HIIT) induced modifications in adipose tissue structure and factors that regulate adipose tissue remodelling, metabolism and the inflammatory signal pathway in adults with obesity, even without weight loss (with no meaningful differences between MICT and HIIT). The modest modifications in adipose tissue structure in response to 12 weeks of MICT or HIIT did not lead to changes in the rate of fatty acid release from adipose tissue. These results expand our understanding about the effects of two commonly used exercise training prescriptions (MICT and HIIT) on adipose tissue remodelling that may lead to advanced strategies for improving metabolic health outcomes in adults with obesity.
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Affiliation(s)
- Cheehoon Ahn
- Substrate Metabolism Laboratory School of Kinesiology University of Michigan Ann Arbor Michigan 48109
| | - Benjamin J. Ryan
- Substrate Metabolism Laboratory School of Kinesiology University of Michigan Ann Arbor Michigan 48109
| | - Michael W. Schleh
- Substrate Metabolism Laboratory School of Kinesiology University of Michigan Ann Arbor Michigan 48109
| | - Pallavi Varshney
- Substrate Metabolism Laboratory School of Kinesiology University of Michigan Ann Arbor Michigan 48109
| | - Alison C. Ludzki
- Substrate Metabolism Laboratory School of Kinesiology University of Michigan Ann Arbor Michigan 48109
| | - Jenna B. Gillen
- Substrate Metabolism Laboratory School of Kinesiology University of Michigan Ann Arbor Michigan 48109
- Faculty of Kinesiology and Physical Education University of Toronto Toronto Ontario M5S 2C9 Canada
| | - Douglas W. Van Pelt
- Substrate Metabolism Laboratory School of Kinesiology University of Michigan Ann Arbor Michigan 48109
| | - Lisa M. Pitchford
- Substrate Metabolism Laboratory School of Kinesiology University of Michigan Ann Arbor Michigan 48109
| | - Suzette M. Howton
- Substrate Metabolism Laboratory School of Kinesiology University of Michigan Ann Arbor Michigan 48109
| | - Thomas Rode
- Substrate Metabolism Laboratory School of Kinesiology University of Michigan Ann Arbor Michigan 48109
| | - Scott L. Hummel
- Division of Cardiology Department of Internal Medicine University of Michigan Ann Arbor Michigan 48109
- Ann Arbor Veterans Affairs Health System Ann Arbor Michigan 48109
| | - Charles F. Burant
- Division of Metabolism, Endocrinology, and Diabetes Department of Internal Medicine University of Michigan Ann Arbor MI 48109
| | - Jonathan P. Little
- School of Health and Exercise Sciences University of British Columbia Okanagan Campus Kelowna British Columbia V1V 1V7 Canada
| | - Jeffrey F. Horowitz
- Substrate Metabolism Laboratory School of Kinesiology University of Michigan Ann Arbor Michigan 48109
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9
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Verdú E, Homs J, Boadas-Vaello P. Physiological Changes and Pathological Pain Associated with Sedentary Lifestyle-Induced Body Systems Fat Accumulation and Their Modulation by Physical Exercise. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:13333. [PMID: 34948944 PMCID: PMC8705491 DOI: 10.3390/ijerph182413333] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 12/02/2021] [Accepted: 12/10/2021] [Indexed: 12/11/2022]
Abstract
A sedentary lifestyle is associated with overweight/obesity, which involves excessive fat body accumulation, triggering structural and functional changes in tissues, organs, and body systems. Research shows that this fat accumulation is responsible for several comorbidities, including cardiovascular, gastrointestinal, and metabolic dysfunctions, as well as pathological pain behaviors. These health concerns are related to the crosstalk between adipose tissue and body systems, leading to pathophysiological changes to the latter. To deal with these health issues, it has been suggested that physical exercise may reverse part of these obesity-related pathologies by modulating the cross talk between the adipose tissue and body systems. In this context, this review was carried out to provide knowledge about (i) the structural and functional changes in tissues, organs, and body systems from accumulation of fat in obesity, emphasizing the crosstalk between fat and body tissues; (ii) the crosstalk between fat and body tissues triggering pain; and (iii) the effects of physical exercise on body tissues and organs in obese and non-obese subjects, and their impact on pathological pain. This information may help one to better understand this crosstalk and the factors involved, and it could be useful in designing more specific training interventions (according to the nature of the comorbidity).
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Affiliation(s)
- Enrique Verdú
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Department of Medical Sciences, University of Girona, 17003 Girona, Spain;
| | - Judit Homs
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Department of Medical Sciences, University of Girona, 17003 Girona, Spain;
- Department of Physical Therapy, EUSES-University of Girona, 17190 Salt, Spain
| | - Pere Boadas-Vaello
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Department of Medical Sciences, University of Girona, 17003 Girona, Spain;
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10
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Garritson JD, Boudina S. The Effects of Exercise on White and Brown Adipose Tissue Cellularity, Metabolic Activity and Remodeling. Front Physiol 2021; 12:772894. [PMID: 34795599 PMCID: PMC8593176 DOI: 10.3389/fphys.2021.772894] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 10/12/2021] [Indexed: 12/15/2022] Open
Abstract
Emerging evidence suggests a significant functional role of adipose tissue in maintaining whole-body metabolic health. It is well established that obesity leads to compositional and morphological changes in adipose tissue that can contribute to the development of cardiometabolic disorders. Thus, the function and size of adipocytes as well as perfusion and inflammation can significantly impact health outcomes independent of body mass index. Lifestyle interventions such as exercise can improve metabolic homeostasis and reduce the risk for developing cardiometabolic disorders. Adipose tissue displays remarkable plasticity in response to external stimuli such as dietary intervention and exercise. Here we review systemic and local effects of exercise that modulate white and brown adipose tissue cellularity, metabolic function and remodeling in humans and animals.
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Affiliation(s)
- Jacob D Garritson
- Department of Nutrition and Integrative Physiology, College of Health, University of Utah, Salt Lake City, UT, United States
| | - Sihem Boudina
- Department of Nutrition and Integrative Physiology, College of Health, University of Utah, Salt Lake City, UT, United States
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11
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Fu P, Zhu R, Jia J, Hu Y, Wu C, Cieszczyk P, Holmberg HC, Gong L. Aerobic exercise promotes the functions of brown adipose tissue in obese mice via a mechanism involving COX2 in the VEGF signaling pathway. Nutr Metab (Lond) 2021; 18:56. [PMID: 34082784 PMCID: PMC8176720 DOI: 10.1186/s12986-021-00581-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 05/27/2021] [Indexed: 12/18/2022] Open
Abstract
Background High-fat diet (HFD)-induced obesity causes immune cells to infiltrate adipose tissue, leading to chronic inflammation and metabolic syndrome. Brown adipose tissue (BAT) can dissipate the energy produced by lipid oxidation as heat, thereby counteracting obesity. Aerobic exercise activates BAT, but the specific underlying mechanism is still unclear. Methods Male C57BL/6 J mice were divided into a normal diet control group (NC group) and HFD group (H group). After becoming obese, the animals in the H group were subdivided into a control group (HC group) and an exercise group (HE group, with treadmill training). After 4 weeks, the mRNA profile of BAT was determined, and then differentially expressed key genes and pathways were verified in vitro. Results Relative to the NC group, the genes upregulated in the HC group coded mainly for proteins involved in immune system progression and inflammatory and immune responses, while the downregulated genes regulated lipid metabolism and oxidation–reduction. Relative to the HC group, the genes upregulated in the HE group coded for glycolipid metabolism, while those that were downregulated were involved in cell death and apoptosis. VEGF and other signaling pathways were enhanced by aerobic exercise. Interaction analysis revealed that the gene encoding cyclooxygenase 2 (COX2) of the VEGF signaling pathway is central to this process, which was verified by a sympathetic activator (isoprenaline hydrochloride) and COX2 inhibitor (NS-398). Conclusions In mice with HFD-induced obesity, four weeks of aerobic exercise elevated BAT mass and increased the expression of genes related to glycolipid metabolism and anti-inflammatory processes. Several pathways are involved, with COX2 in the VEGF signaling pathway playing a key role.
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Affiliation(s)
- Pengyu Fu
- China Institute of Sport and Health Science, Beijing Sport University, Xinxi Road 48, Haidian District, Beijing, 100084, China.,Department of Physical Education, Northwestern Polytechnical University, West Youyi Road 127, Beilin District, Shaanxi, 710109, China
| | - Rongxin Zhu
- China Institute of Sport and Health Science, Beijing Sport University, Xinxi Road 48, Haidian District, Beijing, 100084, China.,Shanghai Research Institute of Sports Science, Xuhui District, Wuxing Road 87, Shanghai, 200030, China
| | - Jie Jia
- China Institute of Sport and Health Science, Beijing Sport University, Xinxi Road 48, Haidian District, Beijing, 100084, China.,Sport Science College, Beijing Sport University, Xinxi Road 48, Haidian District, Beijing, 100084, China
| | - Yang Hu
- China Institute of Sport and Health Science, Beijing Sport University, Xinxi Road 48, Haidian District, Beijing, 100084, China
| | - Chengjun Wu
- School of Biomedical Engineering, Dalian University of Technology and IC Technology Key Lab of Liaoning, Dalian, 116024, China
| | - Pawel Cieszczyk
- Department of Molecular Biology, Faculty of Physical Education, Gdańsk University of Physical Education and Sport, ul. Kazimierza Górskiego 1, 80-336, Gdańsk, Poland
| | - Hans-Christer Holmberg
- Department of Physiology and Pharmacology, Biomedicum C5, Karolinska Institute, Stockholm, Sweden
| | - Lijing Gong
- China Institute of Sport and Health Science, Beijing Sport University, Xinxi Road 48, Haidian District, Beijing, 100084, China.
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12
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Verboven K, Hansen D. Critical Reappraisal of the Role and Importance of Exercise Intervention in the Treatment of Obesity in Adults. Sports Med 2021; 51:379-389. [PMID: 33332014 DOI: 10.1007/s40279-020-01392-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
In the treatment of obesity in adults, exercise intervention is recommended and some people with obesity even prefer exercise above dietary intervention as a single weight-loss strategy. However, evidence is accumulating that the long-term body weight and adipose tissue mass loss as a result of exercise intervention in these individuals is disappointingly small. Although this could be related to various clinical reasons, more recent evidence reveals that also (patho)physiological abnormalities are involved which cannot be remediated by exercise intervention, especially in metabolically compromised patients. As a result, the role and importance of exercise intervention in the treatment of obesity deserve significant reconsideration to avoid confusion and disappointment amongst clinicians, patients and society. Hence, to reduce adipose tissue mass and body weight, dietary intervention is much more effective than exercise intervention, and is, therefore, of key importance in this endeavour. However, dietary interventions must be supplemented by exercise training to induce clinically relevant changes in specific cardiovascular or metabolic risk factors like blood pressure, blood triglycerides and high-density lipoprotein cholesterol concentrations, as well as visceral adipose tissue mass, physical fitness, muscle mass and strength, quality of life and life expectancy. This allows individuals with obesity to preserve their cardiometabolic health or to shift from a metabolically unhealthy phenotype to a metabolically healthy phenotype. Signifying the true clinical value of exercise interventions might lead to a better understanding and appreciation of the goals and associated effects when implemented in the multidisciplinary treatment of obesity, for which a proper tailoring of exercise prescription is required.
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Affiliation(s)
- Kenneth Verboven
- REVAL-Rehabilitation Research Center, Faculty of Rehabilitation Sciences, Hasselt University, Building A, 3590, AgoralaanDiepenbeek, Belgium. .,BIOMED-Biomedical Research Center, Faculty of Medicine and Life Sciences, Hasselt University, Diepenbeek, Belgium.
| | - Dominique Hansen
- REVAL-Rehabilitation Research Center, Faculty of Rehabilitation Sciences, Hasselt University, Building A, 3590, AgoralaanDiepenbeek, Belgium.,BIOMED-Biomedical Research Center, Faculty of Medicine and Life Sciences, Hasselt University, Diepenbeek, Belgium.,Jessa Hospital, Heart Centre Hasselt, Hasselt, Belgium
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13
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MacDonald TL, Pattamaprapanont P, Pathak P, Fernandez N, Freitas EC, Hafida S, Mitri J, Britton SL, Koch LG, Lessard SJ. Hyperglycaemia is associated with impaired muscle signalling and aerobic adaptation to exercise. Nat Metab 2020; 2:902-917. [PMID: 32694831 PMCID: PMC8278496 DOI: 10.1038/s42255-020-0240-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 06/12/2020] [Indexed: 12/11/2022]
Abstract
Increased aerobic exercise capacity, as a result of exercise training, has important health benefits. However, some individuals are resistant to improvements in exercise capacity, probably due to undetermined genetic and environmental factors. Here, we show that exercise-induced improvements in aerobic capacity are blunted and aerobic remodelling of skeletal muscle is impaired in several animal models associated with chronic hyperglycaemia. Our data point to chronic hyperglycaemia as a potential negative regulator of aerobic adaptation, in part, via glucose-mediated modifications of the extracellular matrix, impaired vascularization and aberrant mechanical signalling in muscle. We also observe low exercise capacity and enhanced c-Jun N-terminal kinase activation in response to exercise in humans with impaired glucose tolerance. Our work indicates that current shifts in dietary and metabolic health, associated with increasing incidence of hyperglycaemia, might impair muscular and organismal adaptations to exercise training, including aerobic capacity as one of its key health outcomes.
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Affiliation(s)
- Tara L MacDonald
- Research Division, Joslin Diabetes Center, Boston, MA, USA
- Harvard Medical School, Harvard University, Boston, MA, USA
- Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | - Pattarawan Pattamaprapanont
- Research Division, Joslin Diabetes Center, Boston, MA, USA
- Harvard Medical School, Harvard University, Boston, MA, USA
- Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | - Prerana Pathak
- Research Division, Joslin Diabetes Center, Boston, MA, USA
| | | | - Ellen C Freitas
- School of Physical Education and Sport, University of São Paulo, Ribeirão Preto, Brazil
| | - Samar Hafida
- Research Division, Joslin Diabetes Center, Boston, MA, USA
- Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | - Joanna Mitri
- Research Division, Joslin Diabetes Center, Boston, MA, USA
- Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | - Steven L Britton
- Department of Molecular and Integrative Physiology, and Department of Anesthesiology, University of Michigan, Ann Arbor, MI, USA
| | - Lauren G Koch
- Department of Physiology and Pharmacology, The University of Toledo, Toledo, OH, USA
| | - Sarah J Lessard
- Research Division, Joslin Diabetes Center, Boston, MA, USA.
- Harvard Medical School, Harvard University, Boston, MA, USA.
- Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA.
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14
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Ludzki AC, Krueger EM, Baldwin TC, Schleh MW, Porsche CE, Ryan BJ, Muir LA, Singer K, Lumeng CN, Horowitz JF. Acute Aerobic Exercise Remodels the Adipose Tissue Progenitor Cell Phenotype in Obese Adults. Front Physiol 2020; 11:903. [PMID: 32848853 PMCID: PMC7399179 DOI: 10.3389/fphys.2020.00903] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 07/06/2020] [Indexed: 12/19/2022] Open
Abstract
Adipose tissue pathology in obese patients often features impaired adipogenesis, angiogenesis, and chronic low-grade inflammation, all of which are regulated in large part by adipose tissue stromal vascular cells [SVC; i.e., non-adipocyte cells within adipose tissue including preadipocytes, endothelial cells (ECs), and immune cells]. Exercise is known to increase subcutaneous adipose tissue lipolysis, but the impact of exercise on SVCs in adipose tissue has not been explored. The purpose of this study was to assess the effects of a session of exercise on preadipocyte, EC, macrophage, and T cell content in human subcutaneous adipose tissue. We collected abdominal subcutaneous adipose tissue samples from 10 obese adults (BMI 33 ± 3 kg/m2, body fat 41 ± 7%) 12 h after a 60 min acute session of endurance exercise (80 ± 3%HRpeak) vs. no acute exercise session. SVCs were isolated by collagenase digestion and stained for flow cytometry. We found that acute exercise reduced preadipocyte content (38 ± 7 vs. 30 ± 13%SVC; p = 0.04). The reduction was driven by a decrease in CD34hi preadipocytes (18 ± 5 vs. 13 ± 6%SVC; p = 0.002), a subset of preadipocytes that generates high lipolytic rate adipocytes ex vivo. Acute exercise did not alter EC content. Acute exercise also did not change total immune cell, macrophage, or T cell content, and future work should assess the effects of exercise on subpopulations of these cells. We conclude that exercise may rapidly regulate the subcutaneous adipose tissue preadipocyte pool in ways that may help attenuate the high lipolytic rates that are commonly found in obesity.
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Affiliation(s)
- Alison C Ludzki
- Substrate Metabolism Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI, United States
| | - Emily M Krueger
- Substrate Metabolism Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI, United States
| | - Toree C Baldwin
- Substrate Metabolism Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI, United States
| | - Michael W Schleh
- Substrate Metabolism Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI, United States
| | - Cara E Porsche
- Department of Pediatrics, Medical School, University of Michigan, Ann Arbor, MI, United States.,Graduate Program in Immunology, Medical School, University of Michigan, Ann Arbor, MI, United States
| | - Benjamin J Ryan
- Substrate Metabolism Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI, United States
| | - Lindsey A Muir
- Department of Computational Medicine and Bioinformatics, Medical School, University of Michigan, Ann Arbor, MI, United States
| | - Kanakadurga Singer
- Department of Pediatrics, Medical School, University of Michigan, Ann Arbor, MI, United States.,Graduate Program in Immunology, Medical School, University of Michigan, Ann Arbor, MI, United States.,Department of Molecular and Integrative Physiology, Medical School, University of Michigan, Ann Arbor, MI, United States
| | - Carey N Lumeng
- Department of Pediatrics, Medical School, University of Michigan, Ann Arbor, MI, United States.,Graduate Program in Immunology, Medical School, University of Michigan, Ann Arbor, MI, United States.,Department of Molecular and Integrative Physiology, Medical School, University of Michigan, Ann Arbor, MI, United States
| | - Jeffrey F Horowitz
- Substrate Metabolism Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI, United States
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15
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16
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Walton RG, Kosmac K, Mula J, Fry CS, Peck BD, Groshong JS, Finlin BS, Zhu B, Kern PA, Peterson CA. Human skeletal muscle macrophages increase following cycle training and are associated with adaptations that may facilitate growth. Sci Rep 2019; 9:969. [PMID: 30700754 PMCID: PMC6353900 DOI: 10.1038/s41598-018-37187-1] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 11/23/2018] [Indexed: 12/26/2022] Open
Abstract
Skeletal muscle macrophages participate in repair and regeneration following injury. However, their role in physiological adaptations to exercise is unexplored. We determined whether endurance exercise training (EET) alters macrophage content and characteristics in response to resistance exercise (RE), and whether macrophages are associated with other exercise adaptations. Subjects provided vastus lateralis biopsies before and after one bout of RE, after 12 weeks of EET (cycling), and after a final bout of RE. M2 macrophages (CD11b+/CD206+) did not increase with RE, but increased in response to EET (P < 0.01). Increases in M2 macrophages were positively correlated with fiber hypertrophy (r = 0.49) and satellite cells (r = 0.47). M2c macrophages (CD206+/CD163+) also increased following EET (P < 0.001), and were associated with fiber hypertrophy (r = 0.64). Gene expression was quantified using NanoString. Following EET, the change in M2 macrophages was positively associated with changes in HGF, IGF1, and extracellular matrix genes. EET decreased expression of IL6 (P < 0.05), C/EBPβ (P < 0.01), and MuRF (P < 0.05), and increased expression of IL-4 (P < 0.01), TNFα (P < 0.01) and the TWEAK receptor FN14 (P < 0.05). The change in FN14 gene expression was inversely associated with changes in C/EBPβ (r = -0.58) and MuRF (r = -0.46) following EET. In cultured human myotubes, siRNA inhibition of FN14 increased expression of C/EBPβ (P < 0.05) and MuRF (P < 0.05). Our data suggest that macrophages contribute to the muscle response to EET, potentially including modulation of TWEAK-FN14 signaling.
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Affiliation(s)
- R Grace Walton
- College of Health Sciences and Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA.
| | - Kate Kosmac
- College of Health Sciences and Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA
| | - Jyothi Mula
- College of Health Sciences and Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA
| | - Christopher S Fry
- Deptartment of Nutrition & Metabolism, School of Health Professions, University of Texas Medical Branch at Galveston, Galveston, Texas, USA
| | - Bailey D Peck
- College of Health Sciences and Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA
| | - Jason S Groshong
- Department of Health Professions, University of Central Florida, Orlando, Florida, USA
| | - Brian S Finlin
- Department of Medicine, Division of Endocrinology, and Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, Kentucky, USA
| | - Beibei Zhu
- Department of Medicine, Division of Endocrinology, and Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, Kentucky, USA
| | - Philip A Kern
- Department of Medicine, Division of Endocrinology, and Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, Kentucky, USA
| | - Charlotte A Peterson
- College of Health Sciences and Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, USA
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17
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Dollet L, Zierath JR. Interplay between diet, exercise and the molecular circadian clock in orchestrating metabolic adaptations of adipose tissue. J Physiol 2019; 597:1439-1450. [PMID: 30615204 DOI: 10.1113/jp276488] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 12/12/2018] [Indexed: 12/12/2022] Open
Abstract
Disruption of circadian rhythmicity induced by prolonged light exposure, altered sleep patterns and shift work is associated with the development of obesity and related metabolic disorders, including type 2 diabetes and cardiovascular diseases. White and brown adipose tissue activity shows circadian rhythmicity, with daily variations in the regulation of metabolic processes such as lipolysis, glucose and lipid uptake, and adipokine secretion. The role of the circadian clock in the regulation of energy homeostasis has raised interest in clock-related strategies to mitigate metabolic disturbances associated with type 2 diabetes, including 'resynchronizing' metabolism through diet or targeting a particular time of a day to potentiate the effect of a pharmacological or physiological treatment. Exercise is an effective intervention to prevent insulin resistance and type 2 diabetes. Beyond its effect on skeletal muscle, exercise training also has a profound effect on adipose tissue. Adipose tissue partly mediates the beneficial effect of exercise on glucose and energy homeostasis, via its metabolic and endocrine function. The interaction between zeitgeber time and diet or exercise is likely to influence the metabolic response of adipose tissue and therefore impact the whole-body phenotype. Understanding the impact of circadian clock systems on human physiology and how this is regulated by exercise in a tissue-specific manner will yield new insights for the management of metabolic disorders.
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Affiliation(s)
- Lucile Dollet
- Department of Physiology and Pharmacology, Section for Integrative Physiology, Karolinska Institutet, Stockholm, Sweden
| | - Juleen R Zierath
- Department of Physiology and Pharmacology, Section for Integrative Physiology, Karolinska Institutet, Stockholm, Sweden.,Department of Molecular Medicine and Surgery, Section for Integrative Physiology, Karolinska Institutet, Stockholm, Sweden.,Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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18
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Ludzki AC, Pataky MW, Cartee GD, Horowitz JF. Acute endurance exercise increases Vegfa mRNA expression in adipose tissue of rats during the early stages of weight gain. Appl Physiol Nutr Metab 2018; 43:751-754. [PMID: 29486133 DOI: 10.1139/apnm-2017-0434] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The aim of this study was to determine the effects of acute exercise on key factors regulating angiogenesis in adipose tissue. Adipose tissue Vegf-a messenger RNA expression was upregulated immediately after acute exercise (p < 0.05) in rats consuming a high-fat diet, but was lower after exercise (p < 0.05) in rats consuming a low-fat diet. Our working hypothesis is that acute exercise augments angiogenic signaling under conditions when adipose tissue is expanding, and with repeated exercise sessions these signals can accrue to enhance vascularization.
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Affiliation(s)
- Alison C Ludzki
- School of Kinesiology, University of Michigan, 401 Washtenaw Ave., Ann Arbor, MI 48109, USA.,School of Kinesiology, University of Michigan, 401 Washtenaw Ave., Ann Arbor, MI 48109, USA
| | - Mark W Pataky
- School of Kinesiology, University of Michigan, 401 Washtenaw Ave., Ann Arbor, MI 48109, USA.,School of Kinesiology, University of Michigan, 401 Washtenaw Ave., Ann Arbor, MI 48109, USA
| | - Gregory D Cartee
- School of Kinesiology, University of Michigan, 401 Washtenaw Ave., Ann Arbor, MI 48109, USA.,School of Kinesiology, University of Michigan, 401 Washtenaw Ave., Ann Arbor, MI 48109, USA
| | - Jeffrey F Horowitz
- School of Kinesiology, University of Michigan, 401 Washtenaw Ave., Ann Arbor, MI 48109, USA.,School of Kinesiology, University of Michigan, 401 Washtenaw Ave., Ann Arbor, MI 48109, USA
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19
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Jialal I, Adams-Huet B, Major A, Devaraj S. Increased fibrosis and angiogenesis in subcutaneous gluteal adipose tissue in nascent metabolic syndrome. DIABETES & METABOLISM 2017; 43:364-367. [DOI: 10.1016/j.diabet.2016.12.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 12/07/2016] [Accepted: 12/15/2016] [Indexed: 01/21/2023]
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20
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Van Pelt DW, Guth LM, Horowitz JF. Aerobic exercise elevates markers of angiogenesis and macrophage IL-6 gene expression in the subcutaneous adipose tissue of overweight-to-obese adults. J Appl Physiol (1985) 2017; 123:1150-1159. [PMID: 28798202 DOI: 10.1152/japplphysiol.00614.2017] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 07/28/2017] [Accepted: 08/07/2017] [Indexed: 01/04/2023] Open
Abstract
Alterations in the inflammatory state, metabolic function, and structure of subcutaneous adipose tissue (SAT) can impact the development of insulin resistance in obesity. Exercise can improve metabolic health in obesity, but the effects of exercise on SAT are not well known. The purpose of this study was to examine the effects of acute exercise and habitual exercise training on mRNA expression of markers of lipid metabolism, inflammation, fibrosis, and hypoxia/angiogenesis in SAT, as well as adipocyte cell size. We recruited overweight-to-obese adults who exercised regularly (ACTIVE: n = 8) or were sedentary (SED: n = 12). The groups were well matched for age (27 ± 1 vs. 24 ± 2 yr), body mass index (29 ± 1 vs. 27 ± 1 kg/m2), and body composition (30 ± 1 vs. 29 ± 1% body fat), but as expected, cardiorespiratory fitness was greater in ACTIVE vs. SED (V̇o2peak: 51 ± 3 vs. 42 ± 1 ml·kg fat-free mass-1·min-1; P = 0.01). Abdominal SAT biopsy samples were obtained before and 1 h after a single session of aerobic exercise (60 min at ~65% V̇o2peak). The exercise session increased SAT mRNA expression of VEGFA, an important regulator of angiogenic processes, in both groups. In addition, SAT from ACTIVE subjects had greater mRNA expression of the endothelial cell marker CD31 compared with SED, which may be a cumulative effect of the transient increases in VEGFA with regular exercise. We also magnetically sorted CD14+ immune cells from SAT samples and found that IL-6 expression was elevated in ACTIVE compared with SED. In conclusion, exercise initiates increases in factors related to angiogenic processes and may promote alterations in macrophage inflammation in SAT.NEW & NOTEWORTHY Acute exercise in overweight/obese adults increased subcutaneous adipose tissue (SAT) mRNA expression of VEGFA, an important regulator of angiogenesis and capillary growth. In addition, subjects that regularly exercise had elevated SAT CD31 mRNA expression and elevated IL-6 mRNA in adipose tissue macrophages compared with nonexercisers. This study demonstrates that aerobic exercise may alter processes related to whole body metabolic outcomes in obesity, such as angiogenesis and immune response, in the SAT of overweight/obese adults.
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Affiliation(s)
- Douglas W Van Pelt
- Substrate Metabolism Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, Michigan
| | - Lisa M Guth
- Substrate Metabolism Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, Michigan
| | - Jeffrey F Horowitz
- Substrate Metabolism Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, Michigan
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21
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Matulewicz N, Stefanowicz M, Nikolajuk A, Karczewska-Kupczewska M. Markers of Adipogenesis, but Not Inflammation, in Adipose Tissue Are Independently Related to Insulin Sensitivity. J Clin Endocrinol Metab 2017. [PMID: 28633482 DOI: 10.1210/jc.2017-00597] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
CONTEXT In obesity, adipose tissue (AT) undergoes dynamic remodeling, including an alternation in adipogenesis, AT-resident cell content, angiogenesis, and turnover of extracellular matrix (ECM) components. Studies of AT in humans have been carried out mostly in people with severe metabolic abnormalities, like type 2 diabetes or morbid obesity. OBJECTIVE The purpose of this study was to investigate subcutaneous AT gene expression of markers of adipogenesis, ECM remodeling, and inflammation in young, healthy, overweight or obese subjects. DESIGN The study group comprised 83 normal-weight, 48 overweight, and 19 obese subjects. Euglycemic hyperinsulinemic clamp, biopsy of subcutaneous AT, and isolation of peripheral blood mononuclear cells (PBMCs) were performed. Gene expression was measured with real-time polymerase chain reaction. RESULTS Overweight/obese subjects had lower AT expression of markers of adipogenesis, insulin signaling, and angiogenesis; higher expression of markers of ECM remodeling; altered expression of genes of the nuclear factor-κ-B (NFκB), but not c-Jun NH2-terminal kinase, pathway; and higher expression of macrophage markers but not markers of other immune cells. In multiple regression analysis, the expression of CEBPA, ADIPOQ, IRS1, IRS2, SLC2A4, and MMP9 was associated with insulin sensitivity independently of body mass index. No differences were found in inflammatory-gene PBMC expression. CONCLUSION Overweight/obesity is associated with altered expression of genes of adipogenesis, insulin signaling, ECM remodeling, and inflammation. NFκB seems to be the earliest inflammatory pathway altered at the transcriptional level in AT. Macrophages seem to be the first immune cells to infiltrate AT. Adipogenesis and ECM remodeling are the initial processes in AT that are independently associated with insulin sensitivity.
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Affiliation(s)
- Natalia Matulewicz
- Department of Metabolic Diseases, Medical University of Bialystok, Poland
| | | | - Agnieszka Nikolajuk
- Department of Prophylaxis of Metabolic Diseases, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Olsztyn, Poland
| | - Monika Karczewska-Kupczewska
- Department of Metabolic Diseases, Medical University of Bialystok, Poland
- Department of Prophylaxis of Metabolic Diseases, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Olsztyn, Poland
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22
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Murach KA, Walton RG, Fry CS, Michaelis SL, Groshong JS, Finlin BS, Kern PA, Peterson CA. Cycle training modulates satellite cell and transcriptional responses to a bout of resistance exercise. Physiol Rep 2016; 4:e12973. [PMID: 27650251 PMCID: PMC5037921 DOI: 10.14814/phy2.12973] [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] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 08/23/2016] [Indexed: 12/17/2022] Open
Abstract
This investigation evaluated whether moderate-intensity cycle ergometer training affects satellite cell and molecular responses to acute maximal concentric/eccentric resistance exercise in middle-aged women. Baseline and 72 h postresistance exercise vastus lateralis biopsies were obtained from seven healthy middle-aged women (56 ± 5 years, BMI 26 ± 1, VO2max 27 ± 4) before and after 12 weeks of cycle training. Myosin heavy chain (MyHC) I- and II-associated satellite cell density and cross-sectional area was determined via immunohistochemistry. Expression of 93 genes representative of the muscle-remodeling environment was also measured via NanoString. Overall fiber size increased ~20% with cycle training (P = 0.052). MyHC I satellite cell density increased 29% in response to acute resistance exercise before endurance training and 50% with endurance training (P < 0.05). Following endurance training, MyHC I satellite cell density decreased by 13% in response to acute resistance exercise (acute resistance × training interaction, P < 0.05). Genes with an interaction effect tracked with satellite cell behavior, increasing in the untrained state and decreasing in the endurance trained state in response to resistance exercise. Similar satellite cell and gene expression response patterns indicate coordinated regulation of the muscle environment to promote adaptation. Moderate-intensity endurance cycle training modulates the response to acute resistance exercise, potentially conditioning the muscle for more intense concentric/eccentric activity. These results suggest that cycle training is an effective endurance exercise modality for promoting growth in middle-aged women, who are susceptible to muscle mass loss with progressing age.
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Affiliation(s)
- Kevin A Murach
- Department of Rehabilitation Sciences, Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, Kentucky
| | - R Grace Walton
- Department of Rehabilitation Sciences, Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, Kentucky
| | - Christopher S Fry
- Department of Nutrition and Metabolism, University of Texas Medical Branch, Galveston, Texas
| | - Sami L Michaelis
- Department of Rehabilitation Sciences, Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, Kentucky
| | - Jason S Groshong
- Department of Rehabilitation Sciences, Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, Kentucky
| | - Brian S Finlin
- Division of Endocrinology, and Barnstable Brown Diabetes and Obesity Center, Department of Medicine, University of Kentucky, Lexington, Kentucky
| | - Philip A Kern
- Division of Endocrinology, and Barnstable Brown Diabetes and Obesity Center, Department of Medicine, University of Kentucky, Lexington, Kentucky
| | - Charlotte A Peterson
- Department of Rehabilitation Sciences, Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, Kentucky
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23
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Böhm A, Weigert C, Staiger H, Häring HU. Exercise and diabetes: relevance and causes for response variability. Endocrine 2016; 51:390-401. [PMID: 26643313 PMCID: PMC4762932 DOI: 10.1007/s12020-015-0792-6] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 10/28/2015] [Indexed: 12/31/2022]
Abstract
Exercise as a key prevention strategy for diabetes and obesity is commonly accepted and recommended throughout the world. Unfortunately, not all individuals profit to the same extent, some exhibit exercise resistance. This phenomenon of non-response to exercise is found for several endpoints, including glucose tolerance and insulin sensitivity. Since these non-responders are of notable quantity, there is the need to understand the underlying mechanisms and to identify predictors of response. This displays the basis to develop personalized training intervention regimes. In this review, we summarize the current knowledge on response variability, with focus on human studies and improvement of glucose homeostasis as outcome.
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Affiliation(s)
- Anja Böhm
- Department of Internal Medicine IV, Division of Endocrinology, Diabetology, Angiology, Nephrology, and Clinical Chemistry, University Hospital Tübingen, Eberhard Karls University Tübingen, 72076, Tübingen, Germany
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the Eberhard Karls University Tübingen, Tübingen, Germany
- German Center for Diabetes Research (DZD), 85764, München-Neuherberg, Germany
| | - Cora Weigert
- Department of Internal Medicine IV, Division of Endocrinology, Diabetology, Angiology, Nephrology, and Clinical Chemistry, University Hospital Tübingen, Eberhard Karls University Tübingen, 72076, Tübingen, Germany
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the Eberhard Karls University Tübingen, Tübingen, Germany
- German Center for Diabetes Research (DZD), 85764, München-Neuherberg, Germany
| | - Harald Staiger
- Department of Internal Medicine IV, Division of Endocrinology, Diabetology, Angiology, Nephrology, and Clinical Chemistry, University Hospital Tübingen, Eberhard Karls University Tübingen, 72076, Tübingen, Germany
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the Eberhard Karls University Tübingen, Tübingen, Germany
- German Center for Diabetes Research (DZD), 85764, München-Neuherberg, Germany
| | - Hans-Ulrich Häring
- Department of Internal Medicine IV, Division of Endocrinology, Diabetology, Angiology, Nephrology, and Clinical Chemistry, University Hospital Tübingen, Eberhard Karls University Tübingen, 72076, Tübingen, Germany.
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the Eberhard Karls University Tübingen, Tübingen, Germany.
- German Center for Diabetes Research (DZD), 85764, München-Neuherberg, Germany.
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24
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Arentson-Lantz EJ, English KL, Paddon-Jones D, Fry CS. Fourteen days of bed rest induces a decline in satellite cell content and robust atrophy of skeletal muscle fibers in middle-aged adults. J Appl Physiol (1985) 2016; 120:965-75. [PMID: 26796754 DOI: 10.1152/japplphysiol.00799.2015] [Citation(s) in RCA: 124] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 01/20/2016] [Indexed: 01/06/2023] Open
Abstract
Bed rest, a ground-based spaceflight analog, induces robust atrophy of skeletal muscle, an effect that is exacerbated with increasing age. We examined the effect of 14 days of bed rest on skeletal muscle satellite cell content and fiber type atrophy in middle-aged adults, an understudied age demographic with few overt signs of muscle aging that is representative of astronauts who perform long-duration spaceflight. Muscle biopsies were obtained from the vastus lateralis of healthy middle-aged adults [n= 7 (4 male, 3 female); age: 51 ± 1 yr] before (Pre-BR) and after (Post-BR) 14 days of bed rest. Immunohistochemical analyses were used to quantify myosin heavy chain (MyHC) isoform expression, cross-sectional area (CSA), satellite cell and myonuclear content, and capillary density. Peak oxygen consumption, knee extensor strength, and body composition were also measured Pre-BR and Post-BR. Post-BR MyHC type 2a fiber percentage was reduced, and mean CSA decreased in all fiber types (-24 ± 5%;P< 0.05). Satellite cell content was also reduced Post-BR (-39 ± 9%;P< 0.05), and the change in satellite cell content was significantly correlated with the change in mean fiber CSA (r(2)= 0.60;P< 0.05). A decline in capillary density was observed Post-BR (-23 ± 6%;P< 0.05), and Post-BR capillary content was significantly associated with Post-BR peak aerobic capacity (r(2)= 0.59;P< 0.05). A subtle decline in myonuclear content occurred during bed rest (-5 ± 1%;P< 0.05). The rapid maladaptation of skeletal muscle to 14 days of mechanical unloading in middle-aged adults emphasizes the need for robust countermeasures to preserve muscle function in astronauts.
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Affiliation(s)
- Emily J Arentson-Lantz
- Department of Nutrition and Metabolism, University of Texas Medical Branch, Galveston, Texas; Division of Rehabilitation Sciences, University of Texas Medical Branch, Galveston, Texas
| | - Kirk L English
- Department of Nutrition and Metabolism, University of Texas Medical Branch, Galveston, Texas; Division of Rehabilitation Sciences, University of Texas Medical Branch, Galveston, Texas
| | - Douglas Paddon-Jones
- Department of Nutrition and Metabolism, University of Texas Medical Branch, Galveston, Texas; Division of Rehabilitation Sciences, University of Texas Medical Branch, Galveston, Texas; Sealy Center on Aging, University of Texas Medical Branch, Galveston, Texas
| | - Christopher S Fry
- Department of Nutrition and Metabolism, University of Texas Medical Branch, Galveston, Texas; Division of Rehabilitation Sciences, University of Texas Medical Branch, Galveston, Texas; Sealy Center on Aging, University of Texas Medical Branch, Galveston, Texas
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