1
|
Townsend LK, Steinberg GR. AMPK and the Endocrine Control of Metabolism. Endocr Rev 2023; 44:910-933. [PMID: 37115289 DOI: 10.1210/endrev/bnad012] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 03/10/2023] [Accepted: 04/24/2023] [Indexed: 04/29/2023]
Abstract
Complex multicellular organisms require a coordinated response from multiple tissues to maintain whole-body homeostasis in the face of energetic stressors such as fasting, cold, and exercise. It is also essential that energy is stored efficiently with feeding and the chronic nutrient surplus that occurs with obesity. Mammals have adapted several endocrine signals that regulate metabolism in response to changes in nutrient availability and energy demand. These include hormones altered by fasting and refeeding including insulin, glucagon, glucagon-like peptide-1, catecholamines, ghrelin, and fibroblast growth factor 21; adipokines such as leptin and adiponectin; cell stress-induced cytokines like tumor necrosis factor alpha and growth differentiating factor 15, and lastly exerkines such as interleukin-6 and irisin. Over the last 2 decades, it has become apparent that many of these endocrine factors control metabolism by regulating the activity of the AMPK (adenosine monophosphate-activated protein kinase). AMPK is a master regulator of nutrient homeostasis, phosphorylating over 100 distinct substrates that are critical for controlling autophagy, carbohydrate, fatty acid, cholesterol, and protein metabolism. In this review, we discuss how AMPK integrates endocrine signals to maintain energy balance in response to diverse homeostatic challenges. We also present some considerations with respect to experimental design which should enhance reproducibility and the fidelity of the conclusions.
Collapse
Affiliation(s)
- Logan K Townsend
- Centre for Metabolism Obesity and Diabetes Research, Hamilton, ON L8S 4L8, Canada
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Gregory R Steinberg
- Centre for Metabolism Obesity and Diabetes Research, Hamilton, ON L8S 4L8, Canada
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, ON L8S 4L8, Canada
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4L8, Canada
| |
Collapse
|
2
|
Chang YC, Chan MH, Yang YF, Li CH, Hsiao M. Glucose transporter 4: Insulin response mastermind, glycolysis catalyst and treatment direction for cancer progression. Cancer Lett 2023; 563:216179. [PMID: 37061122 DOI: 10.1016/j.canlet.2023.216179] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 03/27/2023] [Accepted: 04/07/2023] [Indexed: 04/17/2023]
Abstract
The glucose transporter family (GLUT) consists of fourteen members. It is responsible for glucose homeostasis and glucose transport from the extracellular space to the cell cytoplasm to further cascade catalysis. GLUT proteins are encoded by the solute carrier family 2 (SLC2) genes and are members of the major facilitator superfamily of membrane transporters. Moreover, different GLUTs also have their transporter kinetics and distribution, so each GLUT member has its uniqueness and importance to play essential roles in human physiology. Evidence from many studies in the field of diabetes showed that GLUT4 travels between the plasma membrane and intracellular vesicles (GLUT4-storage vesicles, GSVs) and that the PI3K/Akt pathway regulates this activity in an insulin-dependent manner or by the AMPK pathway in response to muscle contraction. Moreover, some published results also pointed out that GLUT4 mediates insulin-dependent glucose uptake. Thus, dysfunction of GLUT4 can induce insulin resistance, metabolic reprogramming in diverse chronic diseases, inflammation, and cancer. In addition to the relationship between GLUT4 and insulin response, recent studies also referred to the potential upstream transcription factors that can bind to the promoter region of GLUT4 to regulating downstream signals. Combined all of the evidence, we conclude that GLUT4 has shown valuable unknown functions and is of clinical significance in cancers, which deserves our in-depth discussion and design compounds by structure basis to achieve therapeutic effects. Thus, we intend to write up a most updated review manuscript to include the most recent and critical research findings elucidating how and why GLUT4 plays an essential role in carcinogenesis, which may have broad interests and impacts on this field.
Collapse
Affiliation(s)
- Yu-Chan Chang
- Department of Biomedical Imaging and Radiological Science, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Ming-Hsien Chan
- Department of Biomedical Imaging and Radiological Science, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Yi-Fang Yang
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Chien-Hsiu Li
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
| | - Michael Hsiao
- Genomics Research Center, Academia Sinica, Taipei, Taiwan; Department of Biochemistry, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
| |
Collapse
|
3
|
Dennis KMJH, Heather LC. Post-translational palmitoylation of metabolic proteins. Front Physiol 2023; 14:1122895. [PMID: 36909239 PMCID: PMC9998952 DOI: 10.3389/fphys.2023.1122895] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 02/03/2023] [Indexed: 03/14/2023] Open
Abstract
Numerous cellular proteins are post-translationally modified by addition of a lipid group to their structure, which dynamically influences the proteome by increasing hydrophobicity of proteins often impacting protein conformation, localization, stability, and binding affinity. These lipid modifications include myristoylation and palmitoylation. Palmitoylation involves a 16-carbon saturated fatty acyl chain being covalently linked to a cysteine thiol through a thioester bond. Palmitoylation is unique within this group of modifications, as the addition of the palmitoyl group is reversible and enzyme driven, rapidly affecting protein targeting, stability and subcellular trafficking. The palmitoylation reaction is catalyzed by a large family of Asp-His-His-Cys (DHHCs) motif-containing palmitoyl acyltransferases, while the reverse reaction is catalyzed by acyl-protein thioesterases (APTs), that remove the acyl chain. Palmitoyl-CoA serves an important dual purpose as it is not only a key metabolite fueling energy metabolism, but is also a substrate for this PTM. In this review, we discuss protein palmitoylation in regulating substrate metabolism, focusing on membrane transport proteins and kinases that participate in substrate uptake into the cell. We then explore the palmitoylation of mitochondrial proteins and the palmitoylation regulatory enzymes, a less explored field for potential lipid metabolic regulation.
Collapse
Affiliation(s)
- Kaitlyn M J H Dennis
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Lisa C Heather
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| |
Collapse
|
4
|
Skeletal-Muscle-Specific Overexpression of Chrono Leads to Disruption of Glucose Metabolism and Exercise Capacity. LIFE (BASEL, SWITZERLAND) 2022; 12:life12081233. [PMID: 36013411 PMCID: PMC9410257 DOI: 10.3390/life12081233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 08/07/2022] [Accepted: 08/09/2022] [Indexed: 11/17/2022]
Abstract
Disruption of circadian rhythms is related to disorders of glucose metabolism, and the molecular clock also exists in skeletal muscle. The ChIP-derived repressor of network oscillator (Chrono) and brain and muscle ARNT-like 1 (Bmal1) are core circadian components. Chrono is considered to be the repressor of Bmal1, and the Chrono–Bmal1 pathway is important in regulating the circadian rhythm; it has been speculated that this pathway could be a new mechanism for regulating glucose metabolism. The purpose of this study was to investigate the effects of Chrono on glucose metabolism in skeletal muscle and exercise capacity by using mice with skeletal-muscle-specific overexpression of Chrono (Chrono TG) and wild-type (WT) mice as the animal models. The results of this cross-sectional study indicated that the Chrono TG mice had an impaired glucose tolerance, lower exercise capacity, and higher levels of nonfasted blood glucose and glycogen content in skeletal muscle compared to WT mice. In addition, the Chrono TG mice also showed a significant increase in the amount of Chrono bound to Bmal1 according to a co-IP analysis; a remarkable decrease in mRNA expression of Tbc1d1, Glut4, Hk2, Pfkm, Pdp1, Gbe1, and Phka1, as well as in activity of Hk and protein expression of Ldhb; but higher mRNA expression of Pdk4 and protein expression of Ldha compared with those of WT mice. These data suggested the skeletal-muscle-specific overexpression of Chrono led to a greater amount of Chrono bound to Bmal1, which then could affect the glucose transporter, glucose oxidation, and glycogen utilization in skeletal muscle, as well as exercise capacity.
Collapse
|
5
|
Zheng A, Arias EB, Wang H, Kwak SE, Pan X, Duan D, Cartee GD. Exercise-Induced Improvement in Insulin-Stimulated Glucose Uptake by Rat Skeletal Muscle Is Absent in Male AS160-Knockout Rats, Partially Restored by Muscle Expression of Phosphomutated AS160, and Fully Restored by Muscle Expression of Wild-Type AS160. Diabetes 2022; 71:219-232. [PMID: 34753801 PMCID: PMC8914290 DOI: 10.2337/db21-0601] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 11/03/2021] [Indexed: 11/13/2022]
Abstract
One exercise session can elevate insulin-stimulated glucose uptake (ISGU) in skeletal muscle, but the mechanisms remain elusive. Circumstantial evidence suggests a role for Akt substrate of 160 kDa (AS160 or TBC1D4). We used genetic approaches to rigorously test this idea. The initial experiment evaluated the role of AS160 in postexercise increase in ISGU using muscles from male wild-type (WT) and AS160-knockout (KO) rats. The next experiment used AS160-KO rats with an adeno-associated virus (AAV) approach to determine if rescuing muscle AS160 deficiency could restore the ability of exercise to improve ISGU. The third experiment tested if eliminating the muscle GLUT4 deficit in AS160-KO rats via AAV-delivered GLUT4 would enable postexercise enhancement of ISGU. The final experiment used AS160-KO rats and AAV delivery of AS160 mutated to prevent phosphorylation of Ser588, Thr642, and Ser704 to evaluate their role in postexercise ISGU. We discovered the following: 1) AS160 expression was essential for postexercise increase in ISGU; 2) rescuing muscle AS160 expression of AS160-KO rats restored postexercise enhancement of ISGU; 3) restoring GLUT4 expression in AS160-KO muscle did not rescue the postexercise increase in ISGU; and 4) although AS160 phosphorylation on three key sites was not required for postexercise elevation in ISGU, it was essential for the full exercise effect.
Collapse
Affiliation(s)
- Amy Zheng
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI
| | - Edward B. Arias
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI
| | - Haiyan Wang
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI
| | - Seong Eun Kwak
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI
| | - Xiufang Pan
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO
| | - Dongsheng Duan
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO
- Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO
- Department of Neurology, School of Medicine, University of Missouri, Columbia, MO
- Department of Biomedical, Biological & Chemical Engineering, College of Engineering, University of Missouri, Columbia, MO
| | - Gregory D. Cartee
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI
- Institute of Gerontology, University of Michigan, Ann Arbor, MI
- Corresponding author: Gregory D. Cartee,
| |
Collapse
|
6
|
Wang H, Zheng A, Arias EB, Cartee GD. Prior AICAR induces elevated glucose uptake concomitant with greater γ3-AMPK activation and reduced membrane cholesterol in skeletal muscle from 26-month-old rats. Facets (Ott) 2022; 7:774-791. [PMID: 36381195 PMCID: PMC9648397 DOI: 10.1139/facets-2021-0166] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/05/2024] Open
Abstract
Attenuated skeletal muscle glucose uptake (GU) has been observed with advancing age. It is important to elucidate the mechanisms linked to interventions that oppose this detrimental outcome. Earlier research using young rodents and (or) cultured myocytes reported that treatment with 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside (AICAR; an AMP-activated protein kinase (AMPK) activator) can increase γ3-AMPK activity and reduce membrane cholesterol content, each of which has been proposed to elevate GU. However, the effect of AICAR treatment on γ3-AMPK activity and membrane cholesterol in skeletal muscle of aged animals has not been reported. Our purpose was to evaluate the effects of AICAR treatment on these potential mechanisms for enhanced glucose uptake in the skeletal muscle of aged animals. Epitrochlearis muscles from 26-27-month-old male rats were isolated and incubated ± AICAR, followed by 3 h incubation without AICAR, and then incubation with 3-O-methyl-[3 H] glucose (to assess GU ± insulin). Muscles were also analyzed for γ3-AMPK activity and membrane cholesterol content. Prior AICAR treatment led to increased γ3-AMPK activity, reduced membrane cholesterol content, and enhanced glucose uptake in skeletal muscle from aged rats. These observations revealed that two potential mechanisms for greater GU previously observed in younger animals and (or) cell models are also potentially relevant for enhanced GU by muscles from older animals.
Collapse
Affiliation(s)
- Haiyan Wang
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI, USA
| | - Amy Zheng
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI, USA
| | - Edward B. Arias
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI, USA
| | - Gregory D. Cartee
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI, USA
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
- Institute of Gerontology, University of Michigan, Ann Arbor, MI, USA
| |
Collapse
|
7
|
Interactions between insulin and exercise. Biochem J 2021; 478:3827-3846. [PMID: 34751700 DOI: 10.1042/bcj20210185] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 10/11/2021] [Accepted: 10/13/2021] [Indexed: 02/06/2023]
Abstract
The interaction between insulin and exercise is an example of balancing and modifying the effects of two opposing metabolic regulatory forces under varying conditions. While insulin is secreted after food intake and is the primary hormone increasing glucose storage as glycogen and fatty acid storage as triglycerides, exercise is a condition where fuel stores need to be mobilized and oxidized. Thus, during physical activity the fuel storage effects of insulin need to be suppressed. This is done primarily by inhibiting insulin secretion during exercise as well as activating local and systemic fuel mobilizing processes. In contrast, following exercise there is a need for refilling the fuel depots mobilized during exercise, particularly the glycogen stores in muscle. This process is facilitated by an increase in insulin sensitivity of the muscles previously engaged in physical activity which directs glucose to glycogen resynthesis. In physically trained individuals, insulin sensitivity is also higher than in untrained individuals due to adaptations in the vasculature, skeletal muscle and adipose tissue. In this paper, we review the interactions between insulin and exercise during and after exercise, as well as the effects of regular exercise training on insulin action.
Collapse
|
8
|
Schnurr TM, Jørsboe E, Chadt A, Dahl-Petersen IK, Kristensen JM, Wojtaszewski JFP, Springer C, Bjerregaard P, Brage S, Pedersen O, Moltke I, Grarup N, Al-Hasani H, Albrechtsen A, Jørgensen ME, Hansen T. Physical activity attenuates postprandial hyperglycaemia in homozygous TBC1D4 loss-of-function mutation carriers. Diabetologia 2021; 64:1795-1804. [PMID: 33912980 PMCID: PMC8245392 DOI: 10.1007/s00125-021-05461-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 02/24/2021] [Indexed: 12/28/2022]
Abstract
AIMS/HYPOTHESIS The common muscle-specific TBC1D4 p.Arg684Ter loss-of-function variant defines a subtype of non-autoimmune diabetes in Arctic populations. Homozygous carriers are characterised by elevated postprandial glucose and insulin levels. Because 3.8% of the Greenlandic population are homozygous carriers, it is important to explore possibilities for precision medicine. We aimed to investigate whether physical activity attenuates the effect of this variant on 2 h plasma glucose levels after an oral glucose load. METHODS In a Greenlandic population cohort (n = 2655), 2 h plasma glucose levels were obtained after an OGTT, physical activity was estimated as physical activity energy expenditure and TBC1D4 genotype was determined. We performed TBC1D4-physical activity interaction analysis, applying a linear mixed model to correct for genetic admixture and relatedness. RESULTS Physical activity was inversely associated with 2 h plasma glucose levels (β[main effect of physical activity] -0.0033 [mmol/l] / [kJ kg-1 day-1], p = 6.5 × 10-5), and significantly more so among homozygous carriers of the TBC1D4 risk variant compared with heterozygous carriers and non-carriers (β[interaction] -0.015 [mmol/l] / [kJ kg-1 day-1], p = 0.0085). The estimated effect size suggests that 1 h of vigorous physical activity per day (compared with resting) reduces 2 h plasma glucose levels by an additional ~0.7 mmol/l in homozygous carriers of the risk variant. CONCLUSIONS/INTERPRETATION Physical activity improves glucose homeostasis particularly in homozygous TBC1D4 risk variant carriers via a skeletal muscle TBC1 domain family member 4-independent pathway. This provides a rationale to implement physical activity as lifestyle precision medicine in Arctic populations. DATA REPOSITORY The Greenlandic Cardio-Metabochip data for the Inuit Health in Transition study has been deposited at the European Genome-phenome Archive ( https://www.ebi.ac.uk/ega/dacs/EGAC00001000736 ) under accession EGAD00010001428.
Collapse
Affiliation(s)
- Theresia M Schnurr
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Emil Jørsboe
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- The Bioinformatics Centre, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Alexandra Chadt
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center (DDZ), Leibniz Center for Diabetes research at the Heinrich-Heine-University Duesseldorf, Medical Faculty, Duesseldorf, Germany
- German Center for Diabetes Research (DZD), Duesseldorf, Germany
| | - Inger K Dahl-Petersen
- National Institute of Public Health, University of Southern Denmark, Odense, Denmark
- Steno Diabetes Center Copenhagen, Gentofte, Denmark
| | - Jonas M Kristensen
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Jørgen F P Wojtaszewski
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Christian Springer
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center (DDZ), Leibniz Center for Diabetes research at the Heinrich-Heine-University Duesseldorf, Medical Faculty, Duesseldorf, Germany
- German Center for Diabetes Research (DZD), Duesseldorf, Germany
| | - Peter Bjerregaard
- National Institute of Public Health, University of Southern Denmark, Odense, Denmark
| | - Søren Brage
- Medical Research Council Epidemiology Unit, University of Cambridge, Cambridge, UK
| | - Oluf Pedersen
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ida Moltke
- The Bioinformatics Centre, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Niels Grarup
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Hadi Al-Hasani
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center (DDZ), Leibniz Center for Diabetes research at the Heinrich-Heine-University Duesseldorf, Medical Faculty, Duesseldorf, Germany
- German Center for Diabetes Research (DZD), Duesseldorf, Germany
| | - Anders Albrechtsen
- The Bioinformatics Centre, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Marit E Jørgensen
- National Institute of Public Health, University of Southern Denmark, Odense, Denmark
- Steno Diabetes Center Copenhagen, Gentofte, Denmark
- Greenland Center for Health Research, University of Greenland, Nuuk, Greenland
| | - Torben Hansen
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| |
Collapse
|
9
|
Townsend LK, Weber AJ, Day EA, Shamshoum H, Shaw SJ, Perry CGR, Kemp BE, Steinberg GR, Wright DC. AMPK mediates energetic stress-induced liver GDF15. FASEB J 2021; 35:e21218. [PMID: 33337559 DOI: 10.1096/fj.202000954r] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 10/30/2020] [Accepted: 11/10/2020] [Indexed: 12/11/2022]
Abstract
Growth differentiating factor-15 (GDF15) is an emerging target for the treatment of obesity and metabolic disease partly due to its ability to suppress food intake. GDF15 expression and secretion are thought to be regulated by a cellular integrated stress response, which involves endoplasmic reticulum (ER) stress. AMPK is another cellular stress sensor, but the relationship between AMPK, ER stress, and GDF15 has not been assessed in vivo. Wildtype (WT), AMPK β1 deficient (AMPKβ1-/- ), and CHOP-/- mice were treated with three distinct AMPK activators; AICAR, which is converted to ZMP mimicking the effects of AMP on the AMPKγ isoform, R419, which indirectly activates AMPK through inhibition of mitochondrial respiration, or A769662, a direct AMPK activator which binds the AMPKβ1 isoform ADaM site causing allosteric activation. Following treatments, liver Gdf15, markers of ER-stress, AMPK activity, adenine nucleotides, circulating GDF15, and food intake were assessed. AICAR and R419 caused ER and energetic stress, increased GDF15 expression and secretion, and suppressed food intake. Direct activation of AMPK β1 containing complexes by A769662 increased hepatic Gdf15 expression, circulating GDF15, and suppressed food intake, independent of ER stress. The effects of AICAR, R419, and A769662 on GDF15 were attenuated in AMPKβ1-/- mice. AICAR and A769662 increased GDF15 to a similar extent in WT and CHOP-/- mice. Herein, we provide evidence that AMPK plays a role in mediating the induction of GDF15 under conditions of energetic stress in mouse liver in vivo.
Collapse
Affiliation(s)
- Logan K Townsend
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada.,Centre for Metabolism, Obesity and Diabetes Research and Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, ON, Canada
| | - Alyssa J Weber
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada
| | - Emily A Day
- Centre for Metabolism, Obesity and Diabetes Research and Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, ON, Canada
| | - Hesham Shamshoum
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada
| | - Simon J Shaw
- Rigel Pharmaceuticals Inc., South San Francisco, CA, USA
| | - Christopher G R Perry
- School of Kinesiology and Health Science, Muscle Health Research Centre, York University, Toronto, ON, Canada
| | - Bruce E Kemp
- Department of Medicine, St. Vincent's Institute, University of Melbourne, Melbourne, Vic, Australia.,Mary MacKillop Institute for Health Research, Australian Catholic University, Fitzroy, Victoria, Australia
| | - Gregory R Steinberg
- Centre for Metabolism, Obesity and Diabetes Research and Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, ON, Canada
| | - David C Wright
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada
| |
Collapse
|
10
|
Gunay A, Shin HH, Gozutok O, Gautam M, Ozdinler PH. Importance of lipids for upper motor neuron health and disease. Semin Cell Dev Biol 2020; 112:92-104. [PMID: 33323321 DOI: 10.1016/j.semcdb.2020.11.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 10/12/2020] [Accepted: 11/11/2020] [Indexed: 12/18/2022]
Abstract
Building evidence reveals the importance of maintaining lipid homeostasis for the health and function of neurons, and upper motor neurons (UMNs) are no exception. UMNs are critically important for the initiation and modulation of voluntary movement as they are responsible for conveying cerebral cortex' input to spinal cord targets. To maintain their unique cytoarchitecture with a prominent apical dendrite and a very long axon, UMNs require a stable cell membrane, a lipid bilayer. Lipids can act as building blocks for many biomolecules, and they also contribute to the production of energy. Therefore, UMNs require sustained control over the production, utilization and homeostasis of lipids. Perturbations of lipid homeostasis lead to UMN vulnerability and progressive degeneration in diseases such as hereditary spastic paraplegia (HSP) and primary lateral sclerosis (PLS). Here, we discuss the importance of lipids, especially for UMNs.
Collapse
Affiliation(s)
- Aksu Gunay
- Department of Neurology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA, 60611
| | - Heather H Shin
- Department of Neurology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA, 60611
| | - Oge Gozutok
- Department of Neurology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA, 60611
| | - Mukesh Gautam
- Department of Neurology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA, 60611
| | - P Hande Ozdinler
- Department of Neurology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA, 60611.
| |
Collapse
|
11
|
Sole-Navais P, Bacelis J, Helgeland Ø, Modzelewska D, Vaudel M, Flatley C, Andreassen O, Njølstad PR, Muglia LJ, Johansson S, Zhang G, Jacobsson B. Autozygosity mapping and time-to-spontaneous delivery in Norwegian parent-offspring trios. Hum Mol Genet 2020; 29:3845-3858. [PMID: 33291140 PMCID: PMC7861013 DOI: 10.1093/hmg/ddaa255] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 11/21/2020] [Accepted: 11/24/2020] [Indexed: 11/18/2022] Open
Abstract
Parental genetic relatedness may lead to adverse health and fitness outcomes in the offspring. However, the degree to which it affects human delivery timing is unknown. We use genotype data from ≃25 000 parent-offspring trios from the Norwegian Mother, Father and Child Cohort Study to optimize runs of homozygosity (ROH) calling by maximizing the correlation between parental genetic relatedness and offspring ROHs. We then estimate the effect of maternal, paternal and fetal autozygosity and that of autozygosity mapping (common segments and gene burden test) on the timing of spontaneous onset of delivery. The correlation between offspring ROH using a variety of parameters and parental genetic relatedness ranged between −0.2 and 0.6, revealing the importance of the minimum number of genetic variants included in an ROH and the use of genetic distance. The optimized compared to predefined parameters showed a ≃45% higher correlation between parental genetic relatedness and offspring ROH. We found no evidence of an effect of maternal, paternal nor fetal overall autozygosity on spontaneous delivery timing. Yet, through autozygosity mapping, we identified three maternal loci TBC1D1, SIGLECs and EDN1 gene regions reducing the median time-to-spontaneous onset of delivery by ≃2–5% (P-value < 2.3 × 10−6). We also found suggestive evidence of a fetal locus at 3q22.2, near the RYK gene region (P-value = 2.0 × 10−6). Autozygosity mapping may provide new insights on the genetic determinants of delivery timing beyond traditional genome-wide association studies, but particular and rigorous attention should be given to ROH calling parameter selection.
Collapse
Affiliation(s)
- Pol Sole-Navais
- Department of Obstetrics and Gynecology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg 41685, Sweden
| | - Jonas Bacelis
- Department of Obstetrics and Gynecology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg 41685, Sweden
| | - Øyvind Helgeland
- Center for Diabetes Research, Department of Clinical Science, University of Bergen, 5020 Bergen, Norway.,Division of Health Data and Digitalization, Department of Genetics and Bioinformatics, Norwegian Institute of Public Health, Oslo 0213, Norway
| | - Dominika Modzelewska
- Department of Obstetrics and Gynecology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg 41685, Sweden
| | - Marc Vaudel
- Center for Diabetes Research, Department of Clinical Science, University of Bergen, 5020 Bergen, Norway.,Department of Pediatrics and Adolescents, Haukeland University Hospital, Bergen 5021, Norway
| | - Christopher Flatley
- Division of Health Data and Digitalization, Department of Genetics and Bioinformatics, Norwegian Institute of Public Health, Oslo 0213, Norway
| | - Ole Andreassen
- NORMENT, University of Oslo, Oslo 0450, Norway.,Division of Mental Health and Addiction, Oslo University Hospital, Oslo 0450, Norway.,Department of Psychiatry, University of California San Diego, San Diego, CA 92093, USA
| | - Pål R Njølstad
- Center for Diabetes Research, Department of Clinical Science, University of Bergen, 5020 Bergen, Norway.,Department of Pediatrics and Adolescents, Haukeland University Hospital, Bergen 5021, Norway
| | - Louis J Muglia
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA.,Division of Human Genetics, The Center for Prevention of Preterm Birth, Perinatal Institute, March of Dimes Prematurity Research Center Ohio Collaborative, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45267, USA
| | - Stefan Johansson
- Center for Diabetes Research, Department of Clinical Science, University of Bergen, 5020 Bergen, Norway.,Center for Medical Genetics, Haukeland University Hospital, Bergen 5021, Norway
| | - Ge Zhang
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA.,Division of Human Genetics, The Center for Prevention of Preterm Birth, Perinatal Institute, March of Dimes Prematurity Research Center Ohio Collaborative, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45267, USA
| | - Bo Jacobsson
- Department of Obstetrics and Gynecology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg 41685, Sweden.,Division of Health Data and Digitalization, Department of Genetics and Bioinformatics, Norwegian Institute of Public Health, Oslo 0213, Norway.,Department of Obstetrics and Gynecology, Sahlgrenska University Hospital, Gothenburg 41685, Sweden
| |
Collapse
|
12
|
Alghamdi F, Alshuweishi Y, Salt IP. Regulation of nutrient uptake by AMP-activated protein kinase. Cell Signal 2020; 76:109807. [DOI: 10.1016/j.cellsig.2020.109807] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 10/05/2020] [Accepted: 10/06/2020] [Indexed: 02/07/2023]
|
13
|
Benninghoff T, Espelage L, Eickelschulte S, Zeinert I, Sinowenka I, Müller F, Schöndeling C, Batchelor H, Cames S, Zhou Z, Kotzka J, Chadt A, Al-Hasani H. The RabGAPs TBC1D1 and TBC1D4 Control Uptake of Long-Chain Fatty Acids Into Skeletal Muscle via Fatty Acid Transporter SLC27A4/FATP4. Diabetes 2020; 69:2281-2293. [PMID: 32868338 DOI: 10.2337/db20-0180] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 08/24/2020] [Indexed: 11/13/2022]
Abstract
The two closely related RabGTPase-activating proteins (RabGAPs) TBC1D1 and TBC1D4 play a crucial role in the regulation of GLUT4 translocation in response to insulin and contraction in skeletal muscle. In mice, deficiency in one or both RabGAPs leads to reduced insulin- and contraction-stimulated glucose uptake and to elevated fatty acid (FA) uptake and oxidation in both glycolytic and oxidative muscle fibers without altering mitochondrial copy number and the abundance of proteins for oxidative phosphorylation. Here we present evidence for a novel mechanism of skeletal muscle lipid utilization involving the two RabGAPs and the FA transporter SLC27A4/FATP4. Both RabGAPs control the uptake of saturated and unsaturated long-chain FAs (LCFAs) into skeletal muscle and knockdown (Kd) of a subset of RabGAP substrates, Rab8, Rab10, or Rab14, decreased LCFA uptake into these cells. In skeletal muscle from Tbc1d1 and Tbc1d4 knockout animals, SLC27A4/FATP4 abundance was increased and depletion of SLC27A4/FATP4 but not FAT/CD36 completely abrogated the enhanced FA oxidation in RabGAP-deficient skeletal muscle and cultivated C2C12 myotubes. Collectively, our data demonstrate that RabGAP-mediated control of skeletal muscle lipid metabolism converges with glucose metabolism at the level of downstream RabGTPases and involves regulated transport of LCFAs via SLC27A4/FATP4.
Collapse
Affiliation(s)
- Tim Benninghoff
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Duesseldorf, Medical Faculty, Duesseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Germany
| | - Lena Espelage
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Duesseldorf, Medical Faculty, Duesseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Germany
| | - Samaneh Eickelschulte
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Duesseldorf, Medical Faculty, Duesseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Germany
| | - Isabel Zeinert
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Duesseldorf, Medical Faculty, Duesseldorf, Germany
| | - Isabelle Sinowenka
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Duesseldorf, Medical Faculty, Duesseldorf, Germany
| | - Frank Müller
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Duesseldorf, Medical Faculty, Duesseldorf, Germany
| | - Christina Schöndeling
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Duesseldorf, Medical Faculty, Duesseldorf, Germany
| | - Hannah Batchelor
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Duesseldorf, Medical Faculty, Duesseldorf, Germany
| | - Sandra Cames
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Duesseldorf, Medical Faculty, Duesseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Germany
| | - Zhou Zhou
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Duesseldorf, Medical Faculty, Duesseldorf, Germany
| | - Jörg Kotzka
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Duesseldorf, Medical Faculty, Duesseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Germany
| | - Alexandra Chadt
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Duesseldorf, Medical Faculty, Duesseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Germany
| | - Hadi Al-Hasani
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Duesseldorf, Medical Faculty, Duesseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Germany
| |
Collapse
|
14
|
Abstract
The glucose transporter GLUT4 is critical for skeletal muscle glucose uptake in response to insulin and muscle contraction/exercise. Exercise increases GLUT4 translocation to the sarcolemma and t-tubule and, over the longer term, total GLUT4 protein content. Here, we review key aspects of GLUT4 biology in relation to exercise, with a focus on exercise-induced GLUT4 translocation, postexercise metabolism and muscle insulin sensitivity, and exercise effects on GLUT4 expression.
Collapse
Affiliation(s)
- Marcelo Flores-Opazo
- Laboratory of Exercise and Physical Activity Sciences, Department of Physiotherapy, University Finis Terrae, Santiago, Chile
| | - Sean L McGee
- Metabolic Research Unit, School of Medicine and Institute for Mental and Physical Health and Clinical Translation (IMPACT), Deakin University, Waurn Ponds
| | - Mark Hargreaves
- Department of Physiology, The University of Melbourne, Melbourne, Australia
| |
Collapse
|
15
|
Hook SC, Chadt A, Heesom KJ, Kishida S, Al-Hasani H, Tavaré JM, Thomas EC. TBC1D1 interacting proteins, VPS13A and VPS13C, regulate GLUT4 homeostasis in C2C12 myotubes. Sci Rep 2020; 10:17953. [PMID: 33087848 PMCID: PMC7578007 DOI: 10.1038/s41598-020-74661-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 09/07/2020] [Indexed: 01/01/2023] Open
Abstract
Proteins involved in the spaciotemporal regulation of GLUT4 trafficking represent potential therapeutic targets for the treatment of insulin resistance and type 2 diabetes. A key regulator of insulin- and exercise-stimulated glucose uptake and GLUT4 trafficking is TBC1D1. This study aimed to identify proteins that regulate GLUT4 trafficking and homeostasis via TBC1D1. Using an unbiased quantitative proteomics approach, we identified proteins that interact with TBC1D1 in C2C12 myotubes including VPS13A and VPS13C, the Rab binding proteins EHBP1L1 and MICAL1, and the calcium pump SERCA1. These proteins associate with TBC1D1 via its phosphotyrosine binding (PTB) domains and their interactions with TBC1D1 were unaffected by AMPK activation, distinguishing them from the AMPK regulated interaction between TBC1D1 and AMPKα1 complexes. Depletion of VPS13A or VPS13C caused a post-transcriptional increase in cellular GLUT4 protein and enhanced cell surface GLUT4 levels in response to AMPK activation. The phenomenon was specific to GLUT4 because other recycling proteins were unaffected. Our results provide further support for a role of the TBC1D1 PTB domains as a scaffold for a range of Rab regulators, and also the VPS13 family of proteins which have been previously linked to fasting glycaemic traits and insulin resistance in genome wide association studies.
Collapse
Affiliation(s)
- Sharon C Hook
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, University Walk, Bristol, BS8 1TD, UK
| | - Alexandra Chadt
- Institute of Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University, Medical Faculty, Düsseldorf, Germany
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
| | - Kate J Heesom
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, University Walk, Bristol, BS8 1TD, UK
| | - Shosei Kishida
- Department of Biochemistry and Genetics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Hadi Al-Hasani
- Institute of Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University, Medical Faculty, Düsseldorf, Germany
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
| | - Jeremy M Tavaré
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, University Walk, Bristol, BS8 1TD, UK
| | - Elaine C Thomas
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, University Walk, Bristol, BS8 1TD, UK.
| |
Collapse
|
16
|
Szpirer C. Rat models of human diseases and related phenotypes: a systematic inventory of the causative genes. J Biomed Sci 2020; 27:84. [PMID: 32741357 PMCID: PMC7395987 DOI: 10.1186/s12929-020-00673-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 07/09/2020] [Indexed: 12/13/2022] Open
Abstract
The laboratory rat has been used for a long time as the model of choice in several biomedical disciplines. Numerous inbred strains have been isolated, displaying a wide range of phenotypes and providing many models of human traits and diseases. Rat genome mapping and genomics was considerably developed in the last decades. The availability of these resources has stimulated numerous studies aimed at discovering causal disease genes by positional identification. Numerous rat genes have now been identified that underlie monogenic or complex diseases and remarkably, these results have been translated to the human in a significant proportion of cases, leading to the identification of novel human disease susceptibility genes, helping in studying the mechanisms underlying the pathological abnormalities and also suggesting new therapeutic approaches. In addition, reverse genetic tools have been developed. Several genome-editing methods were introduced to generate targeted mutations in genes the function of which could be clarified in this manner [generally these are knockout mutations]. Furthermore, even when the human gene causing a disease had been identified without resorting to a rat model, mutated rat strains (in particular KO strains) were created to analyze the gene function and the disease pathogenesis. Today, over 350 rat genes have been identified as underlying diseases or playing a key role in critical biological processes that are altered in diseases, thereby providing a rich resource of disease models. This article is an update of the progress made in this research and provides the reader with an inventory of these disease genes, a significant number of which have similar effects in rat and humans.
Collapse
Affiliation(s)
- Claude Szpirer
- Université Libre de Bruxelles, B-6041, Gosselies, Belgium.
- , Waterloo, Belgium.
| |
Collapse
|
17
|
Brunetta HS, Politis-Barber V, Petrick HL, Dennis KMJH, Kirsh AJ, Barbeau PA, Nunes EA, Holloway GP. Nitrate attenuates high fat diet-induced glucose intolerance in association with reduced epididymal adipose tissue inflammation and mitochondrial reactive oxygen species emission. J Physiol 2020; 598:3357-3371. [PMID: 32449521 DOI: 10.1113/jp279455] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 05/19/2020] [Indexed: 12/20/2023] Open
Abstract
KEY POINTS Dietary nitrate is a prominent therapeutic strategy to mitigate some metabolic deleterious effects related to obesity. Mitochondrial dysfunction is causally linked to adipose tissue inflammation and insulin resistance. Whole-body glucose tolerance is prevented by nitrate independent of body weight and energy expenditure. Dietary nitrate reduces epididymal adipose tissue inflammation and mitochondrial reactive oxygen species emission while preserving insulin signalling. Metabolic beneficial effects of nitrate consumption are associated with improvements in mitochondrial redox balance in hypertrophic adipose tissue. ABSTRACT Evidence has accumulated to indicate that dietary nitrate alters energy expenditure and the metabolic derangements associated with a high fat diet (HFD), but the mechanism(s) of action remain incompletely elucidated. Therefore, we aimed to determine if dietary nitrate (4 mm sodium nitrate via drinking water) could prevent HFD-mediated glucose intolerance in association with improved mitochondrial bioenergetics within both white (WAT) and brown (BAT) adipose tissue in mice. HFD feeding caused glucose intolerance (P < 0.05) and increased body weight. As a result of higher body weight, energy expenditure increased proportionally. HFD-fed mice displayed greater mitochondrial uncoupling and a twofold increase in uncoupling protein 1 content within BAT. Within epididymal white adipose tissue (eWAT), HFD increased cell size (i.e. hypertrophy), mitochondrial H2 O2 emission, oxidative stress, c-Jun N-terminal kinase phosphorylation and leucocyte infiltration, and induced insulin resistance. Remarkably, dietary nitrate consumption attenuated and/or mitigated all these responses, including rendering mitochondria more coupled within BAT, and normalizing mitochondrial H2 O2 emission and insulin-mediated Akt-Thr308 phosphorylation within eWAT. Intriguingly, the positive effects of dietary nitrate appear to be independent of eWAT mitochondrial respiratory capacity and content. Altogether, these data suggest that dietary nitrate attenuates the development of HFD-induced insulin resistance in association with attenuating WAT inflammation and redox balance, independent of changes in either WAT or BAT mitochondrial respiratory capacity/content.
Collapse
Affiliation(s)
- Henver S Brunetta
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
- Department of Physiological Sciences, Federal University of Santa Catarina, Florianopolis, Santa Catarina, Brazil
| | - Valerie Politis-Barber
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Heather L Petrick
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Kaitlyn M J H Dennis
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Aleah J Kirsh
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Pierre-Andre Barbeau
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Everson A Nunes
- Department of Physiological Sciences, Federal University of Santa Catarina, Florianopolis, Santa Catarina, Brazil
| | - Graham P Holloway
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| |
Collapse
|
18
|
Politis-Barber V, Brunetta HS, Paglialunga S, Petrick HL, Holloway GP. Long-term, high-fat feeding exacerbates short-term increases in adipose mitochondrial reactive oxygen species, without impairing mitochondrial respiration. Am J Physiol Endocrinol Metab 2020; 319:E376-E387. [PMID: 32543945 PMCID: PMC7473917 DOI: 10.1152/ajpendo.00028.2020] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
White adipose tissue (WAT) dysfunction in obesity is implicated in the onset of whole body insulin resistance. Alterations in mitochondrial bioenergetics, namely impaired mitochondrial respiration and increased mitochondrial reactive oxygen species (mtROS) production, have been suggested to contribute to this metabolic dysregulation. However, techniques investigating mitochondrial function are classically normalized to tissue weight, which may be confounding when considering obesity-related adipocyte hypertrophy. Furthermore, the effect of long-term high-fat diet (HFD) on mtROS in WAT has yet to be elucidated. Therefore, we sought to determine the HFD-mediated temporal changes in mitochondrial respiration and mtROS emission in WAT. C57BL/6N mice received low-fat diet or HFD for 1 or 8 wk and changes in inguinal WAT (iWAT) and epididymal WAT (eWAT) were assessed. While tissue weight-normalized mitochondrial respiration was reduced in iWAT following 8-wk HFD-feeding, this effect was mitigated when adipocyte cell size and/or number were considered. These data suggest HFD does not impair mitochondrial respiratory capacity per adipocyte within WAT. In support of this assertion, within eWAT compensatory increases in lipid-supported and maximal succinate-supported respiration occurred at 8 wk despite cell hypertrophy and increases in WAT inflammation. Although these data suggest impairments in mitochondrial respiration do not contribute to HFD-mediated WAT phenotype, lipid-supported mtROS emission increased following 1-wk HFD in eWAT, while both lipid and carbohydrate-supported mtROS were increased at 8 wk in both depots. Combined, these data establish that while HFD does not impair adipocyte mitochondrial respiratory capacity, increased mtROS is an enduring physiological occurrence within WAT in HFD-induced obesity.
Collapse
Affiliation(s)
| | - Henver S. Brunetta
- 1Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
- 2Department of Physiological Sciences, Federal University of Santa Catarina, Florianopolis, Brazil
| | - Sabina Paglialunga
- 1Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Heather L. Petrick
- 1Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Graham P. Holloway
- 1Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| |
Collapse
|
19
|
Abstract
The skeletal muscle is the largest organ in the body, by mass. It is also the regulator of glucose homeostasis, responsible for 80% of postprandial glucose uptake from the circulation. Skeletal muscle is essential for metabolism, both for its role in glucose uptake and its importance in exercise and metabolic disease. In this article, we give an overview of the importance of skeletal muscle in metabolism, describing its role in glucose uptake and the diseases that are associated with skeletal muscle metabolic dysregulation. We focus on the role of skeletal muscle in peripheral insulin resistance and the potential for skeletal muscle-targeted therapeutics to combat insulin resistance and diabetes, as well as other metabolic diseases like aging and obesity. In particular, we outline the possibilities and pitfalls of the quest for exercise mimetics, which are intended to target the molecular mechanisms underlying the beneficial effects of exercise on metabolic disease. We also provide a description of the molecular mechanisms that regulate skeletal muscle glucose uptake, including a focus on the SNARE proteins, which are essential regulators of glucose transport into the skeletal muscle. © 2020 American Physiological Society. Compr Physiol 10:785-809, 2020.
Collapse
Affiliation(s)
- Karla E. Merz
- Department of Molecular and Cellular Endocrinology, City of Hope Beckman Research Institute, Duarte, California, USA
- The Irell and Manella Graduate School of Biological Sciences, City of Hope, Duarte, California, USA
| | - Debbie C. Thurmond
- Department of Molecular and Cellular Endocrinology, City of Hope Beckman Research Institute, Duarte, California, USA
| |
Collapse
|
20
|
Barbeau PA, Houad JM, Huber JS, Paglialunga S, Snook LA, Herbst EAF, Dennis KMJH, Simpson JA, Holloway GP. Ablating the Rab-GTPase activating protein TBC1D1 predisposes rats to high-fat diet-induced cardiomyopathy. J Physiol 2020; 598:683-697. [PMID: 31845331 DOI: 10.1113/jp279042] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2019] [Accepted: 12/12/2019] [Indexed: 01/08/2023] Open
Abstract
KEY POINTS Although the role of TBC1D1 within the heart remains unknown, expression of TBC1D1 increases in the left ventricle following an acute infarction, suggesting a biological importance within this tissue. We investigated the mechanistic role of TBC1D1 within the heart, aiming to establish the consequences of attenuating TBC1D1 signalling in the development of diabetic cardiomyopathy, as well as to determine potential sex differences. TBC1D1 ablation increased plasma membrane fatty acid binding protein content and myocardial palmitate oxidation. Following high-fat feeding, TBC1D1 ablation dramatically increased fibrosis and induced end-diastolic dysfunction in both male and female rats in the absence of changes in mitochondrial bioenergetics. Altogether, independent of sex, ablating TBC1D1 predisposes the left ventricle to pathological remodelling following high-fat feeding, and suggests TBC1D1 protects against diabetic cardiomyopathy. ABSTRACT TBC1D1, a Rab-GTPase activating protein, is involved in the regulation of glucose handling and substrate metabolism within skeletal muscle, and is essential for maintaining pancreatic β-cell mass and insulin secretion. However, the function of TBC1D1 within the heart is largely unknown. Therefore, we examined the role of TBC1D1 in the left ventricle and the functional consequence of ablating TBC1D1 on the susceptibility to high-fat diet-induced abnormalities. Since mutations within TBC1D1 (R125W) display stronger associations with clinical parameters in women, we further examined possible sex differences in the predisposition to diabetic cardiomyopathy. In control-fed animals, TBC1D1 ablation did not alter insulin-stimulated glucose uptake, or echocardiogram parameters, but increased accumulation of a plasma membrane fatty acid transporter and the capacity for palmitate oxidation. When challenged with an 8 week high-fat diet, TBC1D1 knockout rats displayed a four-fold increase in fibrosis compared to wild-type animals, and this was associated with diastolic dysfunction, suggesting a predisposition to diet-induced cardiomyopathy. Interestingly, high-fat feeding only induced cardiac hypertrophy in male TBC1D1 knockout animals, implicating a possible sex difference. Mitochondrial respiratory capacity and substrate sensitivity to pyruvate and ADP were not altered by diet or TBC1D1 ablation, nor were markers of oxidative stress, or indices of overt heart failure. Altogether, independent of sex, ablation of TBC1D1 not only increased the susceptibility to high-fat diet-induced diastolic dysfunction and left ventricular fibrosis, independent of sex, but also predisposed male animals to the development of cardiac hypertrophy. These data suggest that TBC1D1 may exert cardioprotective effects in the development of diabetic cardiomyopathy.
Collapse
Affiliation(s)
- Pierre-Andre Barbeau
- Department of Human Health & Nutritional Sciences, University of Guelph, Ontario, Canada
| | - Jacy M Houad
- Department of Human Health & Nutritional Sciences, University of Guelph, Ontario, Canada
| | - Jason S Huber
- Department of Human Health & Nutritional Sciences, University of Guelph, Ontario, Canada
| | - Sabina Paglialunga
- Department of Human Health & Nutritional Sciences, University of Guelph, Ontario, Canada
| | - Laelie A Snook
- Department of Human Health & Nutritional Sciences, University of Guelph, Ontario, Canada
| | - Eric A F Herbst
- Department of Human Health & Nutritional Sciences, University of Guelph, Ontario, Canada
| | - Kaitlyn M J H Dennis
- Department of Human Health & Nutritional Sciences, University of Guelph, Ontario, Canada
| | - Jeremy A Simpson
- Department of Human Health & Nutritional Sciences, University of Guelph, Ontario, Canada
| | - Graham P Holloway
- Department of Human Health & Nutritional Sciences, University of Guelph, Ontario, Canada
| |
Collapse
|
21
|
Pataky MW, Van Acker SL, Dhingra R, Freeburg MM, Arias EB, Oki K, Wang H, Treebak JT, Cartee GD. Fiber type-specific effects of acute exercise on insulin-stimulated AS160 phosphorylation in insulin-resistant rat skeletal muscle. Am J Physiol Endocrinol Metab 2019; 317:E984-E998. [PMID: 31573845 PMCID: PMC6957376 DOI: 10.1152/ajpendo.00304.2019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Muscle is a heterogeneous tissue composed of multiple fiber types. Earlier research revealed fiber type-selective postexercise effects on insulin-stimulated glucose uptake (ISGU) from insulin-resistant rats (increased for type IIA, IIB, IIBX, and IIX, but not type I). In whole muscle from insulin-resistant rats, the exercise increase in ISGU is accompanied by an exercise increase in insulin-stimulated AS160 phosphorylation (pAS160), an ISGU-regulating protein. We hypothesized that, in insulin-resistant muscle, the fiber type-selective exercise effects on ISGU would correspond to the fiber type-selective exercise effects on pAS160. Rats were fed a 2-wk high-fat diet (HFD) and remained sedentary (SED) or exercised before epitrochlearis muscles were dissected either immediately postexercise (IPEX) or at 3 h postexercise (3hPEX) using an exercise protocol that previously revealed fiber type-selective effects on ISGU. 3hPEX muscles and SED controls were incubated ± 100µU/mL insulin. Individual myofibers were isolated and pooled on the basis of myosin heavy chain (MHC) expression, and key phosphoproteins were measured. Myofiber glycogen and MHC expression were evaluated in muscles from other SED, IPEX, and 3hPEX rats. Insulin-stimulated pAktSer473 and pAktThr308 were unaltered by exercise in all fiber types. Insulin-stimulated pAS160 was greater for 3hPEX vs. SED on at least one phosphosite (Ser588, Thr642, and/or Ser704) in type IIA, IIBX, and IIB fibers, but not in type I or IIX fibers. Both IPEX and 3hPEX glycogen were decreased versus SED in all fiber types. These results provided evidence that fiber type-specific pAS160 in insulin-resistant muscle may play a role in the previously reported fiber type-specific elevation in ISGU in some, but not all, fiber types.
Collapse
Affiliation(s)
- Mark W Pataky
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, Michigan
| | - Sydney L Van Acker
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, Michigan
| | - Rhea Dhingra
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, Michigan
| | - Marina M Freeburg
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, Michigan
| | - Edward B Arias
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, Michigan
| | - Kentaro Oki
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, Michigan
| | - Haiyan Wang
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, Michigan
| | - Jonas T Treebak
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Gregory D Cartee
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, Michigan
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan
- Institute of Gerontology, University of Michigan, Ann Arbor, Michigan
| |
Collapse
|
22
|
Sylow L, Richter EA. Current advances in our understanding of exercise as medicine in metabolic disease. CURRENT OPINION IN PHYSIOLOGY 2019. [DOI: 10.1016/j.cophys.2019.04.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
|
23
|
Takahashi Y, Matsunaga Y, Banjo M, Takahashi K, Sato Y, Seike K, Nakano S, Hatta H. Effects of Nutrient Intake Timing on Post-Exercise Glycogen Accumulation and its Related Signaling Pathways in Mouse Skeletal Muscle. Nutrients 2019; 11:nu11112555. [PMID: 31652791 PMCID: PMC6893707 DOI: 10.3390/nu11112555] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 10/17/2019] [Accepted: 10/21/2019] [Indexed: 01/19/2023] Open
Abstract
We investigated the effects of nutrient intake timing on glycogen accumulation and its related signals in skeletal muscle after an exercise that did not induce large glycogen depletion. Male ICR mice ran on a treadmill at 25 m/min for 60 min under a fed condition. Mice were orally administered a solution containing 1.2 mg/g carbohydrate and 0.4 mg/g protein or water either immediately (early nutrient, EN) or 180 min (late nutrient, LN) after the exercise. Tissues were harvested at 30 min after the oral administration. No significant difference in blood glucose or plasma insulin concentrations was found between the EN and LN groups. The plantaris muscle glycogen concentration was significantly (p < 0.05) higher in the EN group—but not in the LN group—compared to the respective time-matched control group. Akt Ser473 phosphorylation was significantly higher in the EN group than in the time-matched control group (p < 0.01), while LN had no effect. Positive main effects of time were found for the phosphorylations in Akt substrate of 160 kDa (AS160) Thr642 (p < 0.05), 5′-AMP-activated protein kinase (AMPK) Thr172 (p < 0.01), and acetyl-CoA carboxylase Ser79 (p < 0.01); however, no effect of nutrient intake was found for these. We showed that delayed nutrient intake could not increase muscle glycogen after endurance exercise which did not induce large glycogen depletion. The results also suggest that post-exercise muscle glycogen accumulation after nutrient intake might be partly influenced by Akt activation. Meanwhile, increased AS160 and AMPK activation by post-exercise fasting might not lead to glycogen accumulation.
Collapse
Affiliation(s)
- Yumiko Takahashi
- Department of Sports Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan.
| | - Yutaka Matsunaga
- Department of Sports Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan.
| | - Mai Banjo
- Department of Sports Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan.
| | - Kenya Takahashi
- Department of Sports Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan.
| | - Yosuke Sato
- Department of Sports Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan.
| | - Kohei Seike
- Department of Sports Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan.
| | - Suguru Nakano
- Department of Sports Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan.
| | - Hideo Hatta
- Department of Sports Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan.
| |
Collapse
|
24
|
Regulation of Skeletal Muscle Glucose Transport and Glucose Metabolism by Exercise Training. Nutrients 2019; 11:nu11102432. [PMID: 31614762 PMCID: PMC6835691 DOI: 10.3390/nu11102432] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Revised: 09/30/2019] [Accepted: 10/08/2019] [Indexed: 12/22/2022] Open
Abstract
Aerobic exercise training and resistance exercise training are both well-known for their ability to improve human health; especially in individuals with type 2 diabetes. However, there are critical differences between these two main forms of exercise training and the adaptations that they induce in the body that may account for their beneficial effects. This article reviews the literature and highlights key gaps in our current understanding of the effects of aerobic and resistance exercise training on the regulation of systemic glucose homeostasis, skeletal muscle glucose transport and skeletal muscle glucose metabolism.
Collapse
|
25
|
Jaiswal N, Gavin MG, Quinn WJ, Luongo TS, Gelfer RG, Baur JA, Titchenell PM. The role of skeletal muscle Akt in the regulation of muscle mass and glucose homeostasis. Mol Metab 2019; 28:1-13. [PMID: 31444134 PMCID: PMC6822261 DOI: 10.1016/j.molmet.2019.08.001] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 07/29/2019] [Accepted: 08/01/2019] [Indexed: 12/15/2022] Open
Abstract
OBJECTIVE Skeletal muscle insulin signaling is a major determinant of muscle growth and glucose homeostasis. Protein kinase B/Akt plays a prominent role in mediating many of the metabolic effects of insulin. Mice and humans harboring systemic loss-of-function mutations in Akt2, the most abundant Akt isoform in metabolic tissues, are glucose intolerant and insulin resistant. Since the skeletal muscle accounts for a significant amount of postprandial glucose disposal, a popular hypothesis in the diabetes field suggests that a reduction in Akt, specifically in skeletal muscle, leads to systemic glucose intolerance and insulin resistance. Despite this common belief, the specific role of skeletal muscle Akt in muscle growth and insulin sensitivity remains undefined. METHODS We generated multiple mouse models of skeletal muscle Akt deficiency to evaluate the role of muscle Akt signaling in vivo. The effects of these genetic perturbations on muscle mass, glucose homeostasis and insulin sensitivity were assessed using both in vivo and ex vivo assays. RESULTS Surprisingly, mice lacking Akt2 alone in skeletal muscle displayed normal skeletal muscle insulin signaling, glucose tolerance, and insulin sensitivity despite a dramatic reduction in phosphorylated Akt. In contrast, deletion of both Akt isoforms (M-AktDKO) prevented downstream signaling and resulted in muscle atrophy. Despite the absence of Akt signaling, in vivo and ex vivo insulin-stimulated glucose uptake were normal in M-AktDKO mice. Similar effects on insulin sensitivity were observed in mice with prolonged deletion (4 weeks) of both skeletal muscle Akt isoforms selectively in adulthood. Conversely, short term deletion (2 weeks) of skeletal muscle specific Akt in adult muscles impaired insulin tolerance paralleling the effect observed by acute pharmacological inhibition of Akt in vitro. Mechanistically, chronic ablation of Akt induced mitochondrial dysfunction and activation of AMPK, which was required for insulin-stimulated glucose uptake in the absence of Akt. CONCLUSIONS Together, these data indicate that chronic reduction in Akt activity alone in skeletal muscle is not sufficient to induce insulin resistance or prevent glucose uptake in all conditions. Therefore, since insulin-stimulated glucose disposal in skeletal muscle is markedly impaired in insulin-resistant states, we hypothesize that alterations in signaling molecules in addition to skeletal muscle Akt are necessary to perturb glucose tolerance and insulin sensitivity in vivo.
Collapse
Affiliation(s)
- N Jaiswal
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - M G Gavin
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - W J Quinn
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - T S Luongo
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - R G Gelfer
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - J A Baur
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA; Department of Physiology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - P M Titchenell
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA; Department of Physiology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.
| |
Collapse
|
26
|
Fu S, Meng Y, Zhang W, Wang J, He Y, Huang L, Chen H, Kuang J, Du H. Transcriptomic Responses of Skeletal Muscle to Acute Exercise in Diabetic Goto-Kakizaki Rats. Front Physiol 2019; 10:872. [PMID: 31338039 PMCID: PMC6629899 DOI: 10.3389/fphys.2019.00872] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 06/21/2019] [Indexed: 12/27/2022] Open
Abstract
Physical activity exerts positive effects on glycemic control in type 2 diabetes (T2D), which is mediated in part by extensive metabolic and molecular remodeling of skeletal muscle in response to exercise, while many regulators of skeletal muscle remain unclear. In the present study, we investigated the effects of acute exercise on skeletal muscle transcriptomic responses in the Goto-Kakizaki (GK) rats which can spontaneously develop T2D. The transcriptomes of skeletal muscle from both 8-week-old GK and Wistar rats that underwent a single exercise session (60 min running using an animal treadmill at 15 m/min) or remained sedentary were analyzed by next-generation RNA sequencing. We identified 819 differentially expressed genes in the sedentary GK rats compared with those of the sedentary Wistar rats. After a single bout of running, we found 291 and 598 genes that were differentially expressed in the exercise GK and exercise Wistar rats when compared with the corresponding sedentary rats. By integrating our data and previous studies including RNA or protein expression patterns and transgenic experiments, the downregulated expression of Fasn and upregulated expression of Tbc1d1, Hk2, Lpin1, Ppargc1a, Sorbs1, and Hmox1 might enhance glucose uptake or improve insulin sensitivity to ameliorate hyperglycemia in the exercise GK rats. Our results provide mechanistic insight into the beneficial effects of exercise on hyperglycemia and insulin action in skeletal muscle of diabetic GK rats.
Collapse
Affiliation(s)
- Shuying Fu
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Yuhuan Meng
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Wenlu Zhang
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Jiajian Wang
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Yuting He
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Lizhen Huang
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Hongmei Chen
- Department of Endocrinology, Guangdong General Hospital/Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Jian Kuang
- Department of Endocrinology, Guangdong General Hospital/Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Hongli Du
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| |
Collapse
|
27
|
Abstract
A pivotal metabolic function of insulin is the stimulation of glucose uptake into muscle and adipose tissues. The discovery of the insulin-responsive glucose transporter type 4 (GLUT4) protein in 1988 inspired its molecular cloning in the following year. It also spurred numerous cellular mechanistic studies laying the foundations for how insulin regulates glucose uptake by muscle and fat cells. Here, we reflect on the importance of the GLUT4 discovery and chronicle additional key findings made in the past 30 years. That exocytosis of a multispanning membrane protein regulates cellular glucose transport illuminated a novel adaptation of the secretory pathway, which is to transiently modulate the protein composition of the cellular plasma membrane. GLUT4 controls glucose transport into fat and muscle tissues in response to insulin and also into muscle during exercise. Thus, investigation of regulated GLUT4 trafficking provides a major means by which to map the essential signaling components that transmit the effects of insulin and exercise. Manipulation of the expression of GLUT4 or GLUT4-regulating molecules in mice has revealed the impact of glucose uptake on whole-body metabolism. Remaining gaps in our understanding of GLUT4 function and regulation are highlighted here, along with opportunities for future discoveries and for the development of therapeutic approaches to manage metabolic disease.
Collapse
Affiliation(s)
- Amira Klip
- Cell Biology Program, Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada
| | - Timothy E McGraw
- Department of Biochemistry, Weill Medical College of Cornell University, New York, New York 10065
| | - David E James
- Charles Perkins Centre, School of Life and Environmental Sciences, Sydney Medical School, University of Sydney, Camperdown, New South Wales 2050, Australia
| |
Collapse
|
28
|
Townsend LK, Medak KD, Peppler WT, Meers GM, Rector RS, LeBlanc PJ, Wright DC. High-saturated-fat diet-induced obesity causes hepatic interleukin-6 resistance via endoplasmic reticulum stress. J Lipid Res 2019; 60:1236-1249. [PMID: 31085628 DOI: 10.1194/jlr.m092510] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Revised: 04/23/2019] [Indexed: 12/14/2022] Open
Abstract
The relationship between liver interleukin-6 (IL-6) resistance following high-fat diet (HFD)-induced obesity and glucose intolerance is unclear. The purpose of this study was to assess the temporal development of hepatic IL-6 resistance and the role of endoplasmic reticulum (ER) stress in this process. We hypothesized that HFD would rapidly induce hepatic IL-6 resistance through a mechanism involving ER stress. Male C57BL/6N mice consumed chow or a HFD (60%) derived from lard (saturated) or olive oil (monounsaturated) for 4 days or 7 weeks before being injected intraperitoneally with IL-6 (6 ng·kg-1). Glucose, insulin, and pyruvate tolerance tests were used as proxies for systemic glucose metabolism and hepatic glucose production, respectively. Primary mouse hepatocytes were incubated with palmitate (saturated) and oleate (unsaturated) overnight, then treated with 20 ng/ml IL-6. ER stress was induced via tunicamycin or prevented by sodium phenylbutyrate (PBA). Seven weeks of a saturated, but not monounsaturated, HFD reduced hepatic IL-6 signaling in conjunction with hepatic ER stress. Palmitate directly impaired IL-6 signaling in hepatocytes along with inducing ER stress. Pharmacologically induced ER stress caused hepatic IL-6 resistance, whereas PBA reversed HFD-induced IL-6 resistance. Chronic HFD-induced obesity is associated with hepatic IL-6 resistance due to saturated FA-induced ER stress.
Collapse
Affiliation(s)
- Logan K Townsend
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada
| | - Kyle D Medak
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada
| | - Willem T Peppler
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada
| | - Grace M Meers
- Division of Gastroenterology and Hepatology, School of Medicine University of Missouri, Columbia, MO.,Research Service, Harry S Truman Memorial VA Hospital, Columbia, MO
| | - R Scott Rector
- Nutrition and Exercise Physiology University of Guelph, Guelph, ON, Canada.,Division of Gastroenterology and Hepatology, School of Medicine University of Missouri, Columbia, MO.,Research Service, Harry S Truman Memorial VA Hospital, Columbia, MO
| | - Paul J LeBlanc
- Department of Health Sciences Brock University, St. Catharines, ON, Canada
| | - David C Wright
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada
| |
Collapse
|
29
|
Williams PhD MV, Cox B, Lafuse PhD WP, Ariza ME. Epstein-Barr Virus dUTPase Induces Neuroinflammatory Mediators: Implications for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Clin Ther 2019; 41:848-863. [PMID: 31040055 PMCID: PMC6525645 DOI: 10.1016/j.clinthera.2019.04.009] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 04/01/2019] [Accepted: 04/01/2019] [Indexed: 01/04/2023]
Abstract
PURPOSE Neuroinflammation is a common feature in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), affecting 85%-90% of all patients, yet the underlying mechanism or mechanisms responsible for the initiation and/or promotion of this process is largely unknown. Multiple reports, however, have suggested a role for Epstein-Barr virus (EBV), in particular, in ME/CFS, but its potential role, if any, in the neuroinflammatory process has not been addressed. In support of this premise, studies by our group have found that the EBV protein deoxyuridine triphosphate nucleotidohydrolase (dUTPase) induces anxiety and sickness behaviors in female mice. We also found that a small subset of patients with ME/CFS exhibited prolonged and significantly elevated neutralizing antibodies against EBV dUTPase protein in serum, which inversely correlated with ME/CFS symptoms. A larger ME/CFS case-control cohort study further confirmed that a significant percentage of patients with ME/CFS (30.91%-52.7%) were simultaneously producing antibodies against multiple human herpesviruses-encoded dUTPases and/or human dUTPase. Altogether, these findings suggest that EBV dUTPase protein may be involved in the neuroinflammatory process observed in ME/CFS. Thus, the aim of the present study was to determine whether the EBV dUTPase protein could contribute to neuroinflammation by altering the expression of genes involved with maintaining blood-brain barrier (BBB) integrity and/or modulating synaptic plasticity. METHODS With the use of human immortalized astrocytes, microglia, and cerebral microvascular endothelial cells, we conducted time-course (0-24 h) experiments with EBV dUTPase protein (10 μg/mL) to determine what effect(s) it may have on the expression of genes involved with BBB permeability, astrocytes and microglia cell function, tryptophan metabolism, and synaptic plasticity by quantitative reverse transcription polymerase chain reaction (qRT-PCR). In parallel, in vivo studies were conducted in female C57Bl/6 mice. Mice were injected by the intraperitoneal route with EBV dUTPase protein (10 μg) or vehicle daily for 5 days, and the brains were collected and processed for further qRT-PCR analysis of the in vivo effect of the dUTPase on the dopamine/serotonin and γ-aminobutyric acid/glutamate pathways, which are important for brain function, using RT2 Profiler PCR Arrays. FINDINGS EBV dUTPase protein altered the expression in vitro (12 of 15 genes and 32 of 1000 proteins examined) and in vivo (34 of 84 genes examined) of targets with central roles in BBB integrity/function, fatigue, pain synapse structure, and function, as well as tryptophan, dopamine, and serotonin metabolism. IMPLICATIONS The data suggest that in a subset of patients with ME/CFS, the EBV dUTPase could initiate a neuroinflammatory reaction, which contributes to the fatigue, excessive pain, and cognitive impairments observed in these patients.
Collapse
Affiliation(s)
- Marshall V Williams PhD
- Department of Cancer Biology and Genetics, The Ohio State University Wexner Medical Center, Columbus, OH, USA; Institute for Behavioral Medicine Research, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Brandon Cox
- Department of Cancer Biology and Genetics, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - William P Lafuse PhD
- Department of Microbial Infection and Immunity, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Maria Eugenia Ariza
- Department of Cancer Biology and Genetics, The Ohio State University Wexner Medical Center, Columbus, OH, USA; Institute for Behavioral Medicine Research, The Ohio State University Wexner Medical Center, Columbus, OH, USA.
| |
Collapse
|
30
|
Lundsgaard AM, Holm JB, Sjøberg KA, Bojsen-Møller KN, Myrmel LS, Fjære E, Jensen BAH, Nicolaisen TS, Hingst JR, Hansen SL, Doll S, Geyer PE, Deshmukh AS, Holst JJ, Madsen L, Kristiansen K, Wojtaszewski JFP, Richter EA, Kiens B. Mechanisms Preserving Insulin Action during High Dietary Fat Intake. Cell Metab 2019; 29:50-63.e4. [PMID: 30269983 DOI: 10.1016/j.cmet.2018.08.022] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 06/21/2018] [Accepted: 08/30/2018] [Indexed: 01/03/2023]
Abstract
Prolonged intervention studies investigating molecular metabolism are necessary for a deeper understanding of dietary effects on health. Here we provide mechanistic information about metabolic adaptation to fat-rich diets. Healthy, slightly overweight men ingested saturated or polyunsaturated fat-rich diets for 6 weeks during weight maintenance. Hyperinsulinemic clamps combined with leg balance technique revealed unchanged peripheral insulin sensitivity, independent of fatty acid type. Both diets increased fat oxidation potential in muscle. Hepatic insulin clearance increased, while glucose production, de novo lipogenesis, and plasma triacylglycerol decreased. High fat intake changed the plasma proteome in the immune-supporting direction and the gut microbiome displayed changes at taxonomical and functional level with polyunsaturated fatty acid (PUFA). In mice, eucaloric feeding of human PUFA and saturated fatty acid diets lowered hepatic triacylglycerol content compared with low-fat-fed control mice, and induced adaptations in the liver supportive of decreased gluconeogenesis and lipogenesis. Intake of fat-rich diets thus induces extensive metabolic adaptations enabling disposition of dietary fat without metabolic complications.
Collapse
Affiliation(s)
- Anne-Marie Lundsgaard
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Universitetsparken 13, Copenhagen 2100, Denmark
| | - Jacob B Holm
- Laboratory of Genomics and Molecular Biomedicine, Department of Biology, University of Copenhagen, Copenhagen, Denmark; Clinical Microbiomics, Copenhagen, Denmark
| | - Kim A Sjøberg
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Universitetsparken 13, Copenhagen 2100, Denmark
| | | | | | - Even Fjære
- Institute of Marine Research, Bergen, Norway
| | - Benjamin A H Jensen
- Laboratory of Genomics and Molecular Biomedicine, Department of Biology, University of Copenhagen, Copenhagen, Denmark; Department of Medicine, Laval University, Quebec, QC, Canada
| | - Trine S Nicolaisen
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Universitetsparken 13, Copenhagen 2100, Denmark
| | - Janne R Hingst
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Universitetsparken 13, Copenhagen 2100, Denmark
| | - Sine L Hansen
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Universitetsparken 13, Copenhagen 2100, Denmark
| | - Sophia Doll
- Department of Proteomics and Signal Transduction, Max-Planck-Institute of Biochemistry, Munich, Germany
| | - Philip E Geyer
- Department of Proteomics and Signal Transduction, Max-Planck-Institute of Biochemistry, Munich, Germany
| | - Atul S Deshmukh
- The Novo Nordisk Foundation Center for Protein Research, Clinical Proteomics, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens J Holst
- Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Lise Madsen
- Laboratory of Genomics and Molecular Biomedicine, Department of Biology, University of Copenhagen, Copenhagen, Denmark; Institute of Marine Research, Bergen, Norway
| | - Karsten Kristiansen
- Laboratory of Genomics and Molecular Biomedicine, Department of Biology, University of Copenhagen, Copenhagen, Denmark; Institute of Metagenomics, BGI-Shenzhen, Shenzhen, China
| | - Jørgen F P Wojtaszewski
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Universitetsparken 13, Copenhagen 2100, Denmark
| | - Erik A Richter
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Universitetsparken 13, Copenhagen 2100, Denmark
| | - Bente Kiens
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Universitetsparken 13, Copenhagen 2100, Denmark.
| |
Collapse
|
31
|
Miotto PM, LeBlanc PJ, Holloway GP. High-Fat Diet Causes Mitochondrial Dysfunction as a Result of Impaired ADP Sensitivity. Diabetes 2018; 67:2199-2205. [PMID: 29980534 DOI: 10.2337/db18-0417] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 06/26/2018] [Indexed: 11/13/2022]
Abstract
Although molecular approaches altering mitochondrial content have implied a direct relationship between mitochondrial bioenergetics and insulin sensitivity, paradoxically, consumption of a high-fat (HF) diet increases mitochondrial content while inducing insulin resistance. We hypothesized that despite the induction of mitochondrial biogenesis, consumption of an HF diet would impair mitochondrial ADP sensitivity in skeletal muscle of mice and therefore manifest in mitochondrial dysfunction in the presence of ADP concentrations indicative of skeletal muscle biology. We found that HF consumption increased mitochondrial protein expression; however, absolute mitochondrial respiration and ADP sensitivity were impaired across a range of biologically relevant ADP concentrations. In addition, HF consumption attenuated the ability of ADP to suppress mitochondrial H2O2 emission, further suggesting impairments in ADP sensitivity. The abundance of ADP transport proteins were not altered, but the sensitivity to carboxyatractyloside-mediated inhibition was attenuated after HF consumption, implicating alterations in adenine nucleotide translocase (ANT) ADP sensitivity in these observations. Moreover, palmitoyl-CoA is known to inhibit ANT, and modeling intramuscular palmitoyl-CoA concentrations that occur after HF consumption exacerbated the deficiency in ADP sensitivity. Altogether, these data suggest that an HF diet induces mitochondrial dysfunction secondary to an intrinsic impairment in mitochondrial ADP sensitivity that is magnified by palmitoyl-CoA.
Collapse
Affiliation(s)
- Paula M Miotto
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Paul J LeBlanc
- Department of Health Sciences, Brock University, St. Catharines, Ontario, Canada
| | - Graham P Holloway
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| |
Collapse
|
32
|
Wang H, Arias EB, Pataky MW, Goodyear LJ, Cartee GD. Postexercise improvement in glucose uptake occurs concomitant with greater γ3-AMPK activation and AS160 phosphorylation in rat skeletal muscle. Am J Physiol Endocrinol Metab 2018; 315:E859-E871. [PMID: 30130149 PMCID: PMC6293165 DOI: 10.1152/ajpendo.00020.2018] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
A single exercise session can increase insulin-stimulated glucose uptake (GU) by skeletal muscle, concomitant with greater Akt substrate of 160 kDa (AS160) phosphorylation on Akt-phosphosites (Thr642 and Ser588) that regulate insulin-stimulated GU. Recent research using mouse skeletal muscle suggested that ex vivo 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) or electrically stimulated contractile activity-inducing increased γ3-AMPK activity and AS160 phosphorylation on a consensus AMPK-motif (Ser704) resulted in greater AS160 Thr642 phosphorylation and GU by insulin-stimulated muscle. Our primary goal was to determine whether in vivo exercise that increases insulin-stimulated GU in rat skeletal muscle would also increase γ3-AMPK activity and AS160 site-selective phosphorylation (Ser588, Thr642, and Ser704) immediately postexercise (IPEX) and/or 3 h postexercise (3hPEX). Epitrochlearis muscles isolated from sedentary and exercised (2-h swim exercise; studied IPEX and 3hPEX) rats were incubated with 2-deoxyglucose to determine GU (without insulin at IPEX; without or with insulin at 3hPEX). Muscles were also assessed for γ1-AMPK activity, γ3-AMPK activity, phosphorylated AMPK (pAMPK), and phosphorylated AS160 (pAS160). IPEX versus sedentary had greater γ3-AMPK activity, pAS160 (Ser588, Thr642, Ser704), and GU with unaltered γ1-AMPK activity. 3hPEX versus sedentary had greater γ3-AMPK activity, pAS160 Ser704, and GU with or without insulin; greater pAS160 Thr642 only with insulin; and unaltered γ1-AMPK activity. These results using an in vivo exercise protocol that increased insulin-stimulated GU in rat skeletal muscle are consistent with the hypothesis that in vivo exercise-induced enhancement of γ3-AMPK activation and AS160 Ser704 IPEX and 3hPEX are important for greater pAS160 Thr642 and enhanced insulin-stimulated GU by skeletal muscle.
Collapse
Affiliation(s)
- Haiyan Wang
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan , Ann Arbor, Michigan
| | - Edward B Arias
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan , Ann Arbor, Michigan
| | - Mark W Pataky
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan , Ann Arbor, Michigan
| | - Laurie J Goodyear
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School , Boston, Massachusetts
| | - Gregory D Cartee
- Muscle Biology Laboratory, School of Kinesiology, University of Michigan , Ann Arbor, Michigan
- Department of Molecular and Integrative Physiology, University of Michigan , Ann Arbor, Michigan
- Institute of Gerontology, University of Michigan , Ann Arbor, Michigan
| |
Collapse
|
33
|
Interactive Roles for AMPK and Glycogen from Cellular Energy Sensing to Exercise Metabolism. Int J Mol Sci 2018; 19:ijms19113344. [PMID: 30373152 PMCID: PMC6274970 DOI: 10.3390/ijms19113344] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 10/15/2018] [Accepted: 10/23/2018] [Indexed: 12/12/2022] Open
Abstract
The AMP-activated protein kinase (AMPK) is a heterotrimeric complex with central roles in cellular energy sensing and the regulation of metabolism and exercise adaptations. AMPK regulatory β subunits contain a conserved carbohydrate-binding module (CBM) that binds glycogen, the major tissue storage form of glucose. Research over the past two decades has revealed that the regulation of AMPK is impacted by glycogen availability, and glycogen storage dynamics are concurrently regulated by AMPK activity. This growing body of research has uncovered new evidence of physical and functional interactive roles for AMPK and glycogen ranging from cellular energy sensing to the regulation of whole-body metabolism and exercise-induced adaptations. In this review, we discuss recent advancements in the understanding of molecular, cellular, and physiological processes impacted by AMPK-glycogen interactions. In addition, we appraise how novel research technologies and experimental models will continue to expand the repertoire of biological processes known to be regulated by AMPK and glycogen. These multidisciplinary research advances will aid the discovery of novel pathways and regulatory mechanisms that are central to the AMPK signaling network, beneficial effects of exercise and maintenance of metabolic homeostasis in health and disease.
Collapse
|
34
|
Knuth CM, Peppler WT, Townsend LK, Miotto PM, Gudiksen A, Wright DC. Prior exercise training improves cold tolerance independent of indices associated with non-shivering thermogenesis. J Physiol 2018; 596:4375-4391. [PMID: 30109697 DOI: 10.1113/jp276228] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 07/12/2018] [Indexed: 12/18/2022] Open
Abstract
KEY POINTS Mammals defend against cold-induced reductions in body temperature through both shivering and non-shivering thermogenesis. The activation of non-shivering thermogenesis is primarily driven by uncoupling protein-1 in brown adipose tissue and to a lesser degree by the browning of white adipose tissue. Endurance exercise has also been shown to increase markers of white adipose tissue browning. This study aimed to determine whether prior exercise training would alter the response to a cold challenge and if this would be associated with differences in indices of non-shivering thermogenesis. It is shown that exercise training protects against cold-induced weight loss by increasing food intake. Exercise-trained mice were better able to maintain their core temperature, independent of differences in markers of non-shivering thermogenesis. ABSTRACT Shivering is one of the first defences against cold, and as skeletal muscle fatigues there is an increased reliance on non-shivering thermogenesis. Brown and beige adipose tissues are the primary thermogenic tissues regulating this process. Exercise has also been shown to increase the thermogenic capacity of subcutaneous white adipose tissue. Whether exercise has an effect on the adaptations to cold stress within adipose tissue and skeletal muscle remains to be shown. Male C57BL/6 mice were either subjected to voluntary wheel running or remained sedentary for 12 days. Exercise led to decreased body weight and increased glucose tolerance. Mice were then divided into groups kept at 25°C room temperature or a cold challenge of 4°C for 48 h. Exercised mice were protected against cold-induced reductions in weight and in parallel with increased food intake. Providing exercised mice with the same amount of food as sedentary mice eliminated the protection against cold-induced weight loss. Cold exposure led to greater reductions in rectal temperature in sedentary compared to exercised mice. This protective effect was not explained by differences in the browning of white adipose tissue or brown adipose tissue mass. Similarly, the ability of the β3 -adrenergic agonist CL 316,243 to increase energy expenditure was attenuated in previously exercised mice, suggesting that the activation of uncoupling protein-1 in brown and/or beige adipocytes is not the source of protective effects. We speculate that the protection against cold-induced reductions in rectal temperature could potentially be linked to exercise-induced alterations in skeletal muscle.
Collapse
Affiliation(s)
- Carly M Knuth
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada N1G 2W1
| | - Willem T Peppler
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada N1G 2W1
| | - Logan K Townsend
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada N1G 2W1
| | - Paula M Miotto
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada N1G 2W1
| | - Anders Gudiksen
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - David C Wright
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada N1G 2W1
| |
Collapse
|
35
|
Stermann T, Menzel F, Weidlich C, Jeruschke K, Weiss J, Altenhofen D, Benninghoff T, Pujol A, Bosch F, Rustenbeck I, Ouwens DM, Thoresen GH, de Wendt C, Lebek S, Schallschmidt T, Kragl M, Lammert E, Chadt A, Al-Hasani H. Deletion of the RabGAP TBC1D1 Leads to Enhanced Insulin Secretion and Fatty Acid Oxidation in Islets From Male Mice. Endocrinology 2018; 159:1748-1761. [PMID: 29481597 DOI: 10.1210/en.2018-00087] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 01/26/2018] [Indexed: 01/24/2023]
Abstract
The Rab guanosine triphosphatase-activating protein (RabGAP) TBC1D1 has been shown to be a key regulator of glucose and lipid metabolism in skeletal muscle. Its function in pancreatic islets, however, is not yet fully understood. Here, we aimed to clarify the specific impact of TBC1D1 on insulin secretion and substrate use in pancreatic islets. We analyzed the dynamics of glucose-stimulated insulin secretion (GSIS) and lipid metabolism in isolated islets from Tbc1d1-deficient (D1KO) mice. To further investigate the underlying cellular mechanisms, we conducted pharmacological studies in these islets. In addition, we determined morphology and number of both pancreatic islets and insulin vesicles in β-cells using light and transmission electron microscopy. Isolated pancreatic islets from D1KO mice exhibited substantially increased GSIS compared with wild-type (WT) controls. This was attributed to both enhanced first and second phase of insulin secretion, and this enhanced secretion persisted during repetitive glucose stimuli. Studies with sulfonylureas or KCl in isolated islets demonstrated that TBC1D1 exerts its function via a signaling pathway at the level of membrane depolarization. In line, ultrastructural analysis of isolated pancreatic islets revealed both higher insulin-granule density and number of docked granules in β-cells from D1KO mice compared with WT controls. Like in skeletal muscle, lipid use in isolated islets was enhanced upon D1KO, presumably as a result of a higher mitochondrial fission rate and/or higher mitochondrial activity. Our results clearly demonstrate a dual role of TBC1D1 in controlling substrate metabolism of the pancreatic islet.
Collapse
Affiliation(s)
- Torben Stermann
- German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Medical Faculty, Duesseldorf, Germany
- German Center for Diabetes Research, Duesseldorf, Germany
| | - Franziska Menzel
- German Institute for Human Nutrition Potsdam-Rehbruecke, Nuthetal, Germany
| | - Carmen Weidlich
- German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Medical Faculty, Duesseldorf, Germany
| | - Kay Jeruschke
- German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Medical Faculty, Duesseldorf, Germany
| | - Jürgen Weiss
- German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Medical Faculty, Duesseldorf, Germany
| | - Delsi Altenhofen
- German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Medical Faculty, Duesseldorf, Germany
- German Center for Diabetes Research, Duesseldorf, Germany
| | - Tim Benninghoff
- German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Medical Faculty, Duesseldorf, Germany
- German Center for Diabetes Research, Duesseldorf, Germany
| | - Anna Pujol
- Center of Animal Biotechnology and Gene Therapy, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Fatima Bosch
- Center of Animal Biotechnology and Gene Therapy, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Ingo Rustenbeck
- Institute of Pharmacology, Toxicology and Clinical Pharmacy, Technical University Braunschweig, Braunschweig, Germany
| | - D Margriet Ouwens
- German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Medical Faculty, Duesseldorf, Germany
| | - G Hege Thoresen
- Department of Pharmaceutical Biosciences, School of Pharmacy, University of Oslo, Oslo, Norway
| | - Christian de Wendt
- German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Medical Faculty, Duesseldorf, Germany
- German Center for Diabetes Research, Duesseldorf, Germany
| | - Sandra Lebek
- German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Medical Faculty, Duesseldorf, Germany
- German Center for Diabetes Research, Duesseldorf, Germany
| | - Tanja Schallschmidt
- German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Medical Faculty, Duesseldorf, Germany
- German Center for Diabetes Research, Duesseldorf, Germany
| | - Martin Kragl
- German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Medical Faculty, Duesseldorf, Germany
- German Center for Diabetes Research, Duesseldorf, Germany
| | - Eckhard Lammert
- German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Medical Faculty, Duesseldorf, Germany
- German Center for Diabetes Research, Duesseldorf, Germany
| | - Alexandra Chadt
- German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Medical Faculty, Duesseldorf, Germany
- German Center for Diabetes Research, Duesseldorf, Germany
| | - Hadi Al-Hasani
- German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Medical Faculty, Duesseldorf, Germany
- German Center for Diabetes Research, Duesseldorf, Germany
| |
Collapse
|
36
|
Lundsgaard AM, Fritzen AM, Kiens B. Molecular Regulation of Fatty Acid Oxidation in Skeletal Muscle during Aerobic Exercise. Trends Endocrinol Metab 2018; 29:18-30. [PMID: 29221849 DOI: 10.1016/j.tem.2017.10.011] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 10/28/2017] [Accepted: 10/30/2017] [Indexed: 01/21/2023]
Abstract
This review summarizes how fatty acid (FA) oxidation is regulated in skeletal muscle during exercise. From the available evidence it seems that acetyl-CoA availability in the mitochondrial matrix adjusts FA oxidation to exercise intensity and duration. This is executed at the step of mitochondrial fatty acyl import, as the extent of acetyl group sequestration by carnitine determines the availability of carnitine for the carnitine palmitoyltransferase 1 (CPT1) reaction. The rate of glycolysis seems therefore to be central to the amount of β-oxidation-derived acetyl-CoA that is oxidized in the tricarboxylic acid (TCA) cycle. FA oxidation during exercise is also determined by FA availability to mitochondria, dependent on trans-sarcolemmal FA uptake via cluster of differentiation 36/SR-B2 (CD36) and FAs mobilized from myocellular lipid droplets.
Collapse
Affiliation(s)
- Anne-Marie Lundsgaard
- Section of Molecular Physiology, Department of Nutrition, Exercise, and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Andreas Mæchel Fritzen
- Section of Molecular Physiology, Department of Nutrition, Exercise, and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Bente Kiens
- Section of Molecular Physiology, Department of Nutrition, Exercise, and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark.
| |
Collapse
|
37
|
Characterisation of L-Type Amino Acid Transporter 1 (LAT1) Expression in Human Skeletal Muscle by Immunofluorescent Microscopy. Nutrients 2017; 10:nu10010023. [PMID: 29278358 PMCID: PMC5793251 DOI: 10.3390/nu10010023] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 11/16/2017] [Accepted: 12/13/2017] [Indexed: 12/21/2022] Open
Abstract
The branch chain amino acid leucine is a potent stimulator of protein synthesis in skeletal muscle. Leucine rapidly enters the cell via the L-Type Amino Acid Transporter 1 (LAT1); however, little is known regarding the localisation and distribution of this transporter in human skeletal muscle. Therefore, we applied immunofluorescence staining approaches to visualise LAT1 in wild type (WT) and LAT1 muscle-specific knockout (mKO) mice, in addition to basal human skeletal muscle samples. LAT1 positive staining was visually greater in WT muscles compared to mKO muscle. In human skeletal muscle, positive LAT1 staining was noted close to the sarcolemmal membrane (dystrophin positive staining), with a greater staining intensity for LAT1 observed in the sarcoplasmic regions of type II fibres (those not stained positively for myosin heavy-chain 1, Type II—25.07 ± 5.93, Type I—13.71 ± 1.98, p < 0.01), suggesting a greater abundance of this protein in these fibres. Finally, we observed association with LAT1 and endothelial nitric oxide synthase (eNOS), suggesting LAT1 association close to the microvasculature. This is the first study to visualise the distribution and localisation of LAT1 in human skeletal muscle. As such, this approach provides a validated experimental platform to study the role and regulation of LAT1 in human skeletal muscle in response to various physiological and pathophysiological models.
Collapse
|