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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]
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Henríquez-Olguin C, Knudsen JR, Raun SH, Li Z, Dalbram E, Treebak JT, Sylow L, Holmdahl R, Richter EA, Jaimovich E, Jensen TE. Cytosolic ROS production by NADPH oxidase 2 regulates muscle glucose uptake during exercise. Nat Commun 2019; 10:4623. [PMID: 31604916 PMCID: PMC6789013 DOI: 10.1038/s41467-019-12523-9] [Citation(s) in RCA: 115] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Accepted: 09/11/2019] [Indexed: 12/11/2022] Open
Abstract
Reactive oxygen species (ROS) act as intracellular compartmentalized second messengers, mediating metabolic stress-adaptation. In skeletal muscle fibers, ROS have been suggested to stimulate glucose transporter 4 (GLUT4)-dependent glucose transport during artificially evoked contraction ex vivo, but whether myocellular ROS production is stimulated by in vivo exercise to control metabolism is unclear. Here, we combined exercise in humans and mice with fluorescent dyes, genetically-encoded biosensors, and NADPH oxidase 2 (NOX2) loss-of-function models to demonstrate that NOX2 is the main source of cytosolic ROS during moderate-intensity exercise in skeletal muscle. Furthermore, two NOX2 loss-of-function mouse models lacking either p47phox or Rac1 presented striking phenotypic similarities, including greatly reduced exercise-stimulated glucose uptake and GLUT4 translocation. These findings indicate that NOX2 is a major myocellular ROS source, regulating glucose transport capacity during moderate-intensity exercise.
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Affiliation(s)
- Carlos Henríquez-Olguin
- Department of Nutrition, Exercise and Sports, Section of Molecular Physiology, University of Copenhagen, Universitetsparken 13, 2100, Copenhagen, Denmark.,Center for Exercise, Metabolism and Cancer, ICBM, Universidad de Chile, 8380453, Santiago, Chile
| | - Jonas R Knudsen
- Department of Nutrition, Exercise and Sports, Section of Molecular Physiology, University of Copenhagen, Universitetsparken 13, 2100, Copenhagen, Denmark
| | - Steffen H Raun
- Department of Nutrition, Exercise and Sports, Section of Molecular Physiology, University of Copenhagen, Universitetsparken 13, 2100, Copenhagen, Denmark
| | - Zhencheng Li
- Department of Nutrition, Exercise and Sports, Section of Molecular Physiology, University of Copenhagen, Universitetsparken 13, 2100, Copenhagen, Denmark
| | - Emilie Dalbram
- Novo Nordisk Foundation Center for Basic Metabolic Research, Integrative Metabolism and Environmental Influence, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3A, 2200, Copenhagen, Denmark
| | - Jonas T Treebak
- Novo Nordisk Foundation Center for Basic Metabolic Research, Integrative Metabolism and Environmental Influence, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3A, 2200, Copenhagen, Denmark
| | - Lykke Sylow
- Department of Nutrition, Exercise and Sports, Section of Molecular Physiology, University of Copenhagen, Universitetsparken 13, 2100, Copenhagen, Denmark
| | - Rikard Holmdahl
- Section for Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Solnavägen 9, 171 65, Solna, Sweden
| | - Erik A Richter
- Department of Nutrition, Exercise and Sports, Section of Molecular Physiology, University of Copenhagen, Universitetsparken 13, 2100, Copenhagen, Denmark
| | - Enrique Jaimovich
- Center for Exercise, Metabolism and Cancer, ICBM, Universidad de Chile, 8380453, Santiago, Chile
| | - Thomas E Jensen
- Department of Nutrition, Exercise and Sports, Section of Molecular Physiology, University of Copenhagen, Universitetsparken 13, 2100, Copenhagen, Denmark.
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Amri J, Parastesh M, Sadegh M, Latifi SA, Alaee M. High-intensity interval training improved fasting blood glucose and lipid profiles in type 2 diabetic rats more than endurance training; possible involvement of irisin and betatrophin. Physiol Int 2019; 106:213-224. [PMID: 31578075 DOI: 10.1556/2060.106.2019.24] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
BACKGROUND AND AIMS In this study, we aimed to investigate the effects of 10 weeks of high-intensity interval training (HIIT) and endurance training (END) on irisin, betatrophin, insulin, fasting blood glucose (FBG) concentrations, and lipid profiles in diabetic rats. METHODS Twenty-four Wistar rats (weight: 200-250 g) were randomly assigned into four groups as follows: (1) control (Cnt), (2) diabetic (Dibt), (3) diabetic HIIT (Dibt-HIIT), and (4) diabetic END (Dibt-END). For inducing diabetes, after 12 h of food starvation, nicotinamide (120 mg/kg) and streptozotocin (STZ; 65 mg/kg) were intraperitoneally injected. The diabetic training groups received 10 weeks of HIIT or END training following the induction of diabetes. Twenty-four hours following the last training session, blood serum samples were collected for evaluating the concentration of irisin, betatrophin, and insulin hormones through enzyme-linked immunosorbent assay. RESULTS FBG and lipid profiles were measured by biochemical kits. A significant increase in the serum concentration of irisin (p < 0.05), betatrophin (p < 0.05), and insulin (p < 0.001) and significant decrease in the FBG (P < 0.01) and lipid profiles (p < 0.01) were observed in the Dibt-HIIT group compared to the Dibt-END group. In addition, irisin revealed a significant positive association with betatrophin and insulin values in diabetic training groups (p < 0.01). CONCLUSIONS It seems that HIIT leads to a more extensive improvement in diabetic conditions compared to the END training. Therefore, HIIT appears to be an important time-efficient approach for the treatment of type 2 diabetes.
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Affiliation(s)
- J Amri
- Traditional and Complementary Medicine Research Center, Arak University of Medical Sciences, Arak, Iran
| | - M Parastesh
- Department of Sports Physiology and Pathology, Faculty of Sport Sciences, Arak University, Arak, Iran
| | - M Sadegh
- Traditional and Complementary Medicine Research Center, Arak University of Medical Sciences, Arak, Iran.,Department of Physiology, Faculty of Medicine, Arak University of Medical Sciences, Arak, Iran
| | - S A Latifi
- Traditional and Complementary Medicine Research Center, Arak University of Medical Sciences, Arak, Iran
| | - M Alaee
- Traditional and Complementary Medicine Research Center, Arak University of Medical Sciences, Arak, Iran
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Bonnet N, Bourgoin L, Biver E, Douni E, Ferrari S. RANKL inhibition improves muscle strength and insulin sensitivity and restores bone mass. J Clin Invest 2019; 129:3214-3223. [PMID: 31120440 PMCID: PMC6668701 DOI: 10.1172/jci125915] [Citation(s) in RCA: 161] [Impact Index Per Article: 32.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 05/14/2019] [Indexed: 12/13/2022] Open
Abstract
Receptor activator of Nfkb ligand (RANKL) activates, while osteoprotegerin (OPG) inhibits, osteoclastogenesis. In turn a neutralizing Ab against RANKL, denosumab improves bone strength in osteoporosis. OPG also improves muscle strength in mouse models of Duchenne's muscular dystrophy (mdx) and denervation-induce atrophy, but its role and mechanisms of action on muscle weakness in other conditions remains to be investigated. We investigated the effects of RANKL inhibitors on muscle in osteoporotic women and mice that either overexpress RANKL (HuRANKL-Tg+), or lack Pparb and concomitantly develop sarcopenia (Pparb-/-). In women, denosumab over 3 years improved appendicular lean mass and handgrip strength compared to no treatment, whereas bisphosphonate did not. HuRANKL-Tg+ mice displayed lower limb force and maximal speed, while their leg muscle mass was diminished, with a lower number of type I and II fibers. Both OPG and denosumab increased limb force proportionally to the increase in muscle mass. They markedly improved muscle insulin sensitivity and glucose uptake, and decrease anti-myogenic and inflammatory gene expression in muscle, such as myostatin and protein tyrosine phosphatase receptor-γ. Similarly, in Pparb-/-, OPG increased muscle volume and force, while also normalizing their insulin signaling and higher expression of inflammatory genes in skeletal muscle. In conclusions, RANKL deteriorates, while its inhibitor improves, muscle strength and insulin sensitivity in osteoporotic mice and humans. Hence denosumab could represent a novel therapeutic approach for sarcopenia.
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Affiliation(s)
- Nicolas Bonnet
- Division of Bone Diseases, Department of Internal Medicine Specialties, Geneva University Hospital & Faculty of Medicine, Geneva, Switzerland
| | - Lucie Bourgoin
- Division of Bone Diseases, Department of Internal Medicine Specialties, Geneva University Hospital & Faculty of Medicine, Geneva, Switzerland
| | - Emmanuel Biver
- Division of Bone Diseases, Department of Internal Medicine Specialties, Geneva University Hospital & Faculty of Medicine, Geneva, Switzerland
| | - Eleni Douni
- Biomedical Sciences Research Center “Alexander Fleming,” Athens, Greece
- Department of Biotechnology, Agricultural University of Athens, Athens, Greece
| | - Serge Ferrari
- Division of Bone Diseases, Department of Internal Medicine Specialties, Geneva University Hospital & Faculty of Medicine, Geneva, Switzerland
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Møller LLV, Klip A, Sylow L. Rho GTPases-Emerging Regulators of Glucose Homeostasis and Metabolic Health. Cells 2019; 8:E434. [PMID: 31075957 PMCID: PMC6562660 DOI: 10.3390/cells8050434] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 05/02/2019] [Accepted: 05/06/2019] [Indexed: 12/11/2022] Open
Abstract
Rho guanosine triphosphatases (GTPases) are key regulators in a number of cellular functions, including actin cytoskeleton remodeling and vesicle traffic. Traditionally, Rho GTPases are studied because of their function in cell migration and cancer, while their roles in metabolism are less documented. However, emerging evidence implicates Rho GTPases as regulators of processes of crucial importance for maintaining metabolic homeostasis. Thus, the time is now ripe for reviewing Rho GTPases in the context of metabolic health. Rho GTPase-mediated key processes include the release of insulin from pancreatic β cells, glucose uptake into skeletal muscle and adipose tissue, and muscle mass regulation. Through the current review, we cast light on the important roles of Rho GTPases in skeletal muscle, adipose tissue, and the pancreas and discuss the proposed mechanisms by which Rho GTPases act to regulate glucose metabolism in health and disease. We also describe challenges and goals for future research.
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Affiliation(s)
- Lisbeth Liliendal Valbjørn Møller
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, 2100 Copenhagen Oe, Denmark.
| | - Amira Klip
- Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada.
| | - Lykke Sylow
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, 2100 Copenhagen Oe, Denmark.
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Wu M, Li L, Hamaker M, Small D, Duffield AS. FLT3-ITD cooperates with Rac1 to modulate the sensitivity of leukemic cells to chemotherapeutic agents via regulation of DNA repair pathways. Haematologica 2019; 104:2418-2428. [PMID: 30975911 PMCID: PMC6959181 DOI: 10.3324/haematol.2018.208843] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 04/09/2019] [Indexed: 01/01/2023] Open
Abstract
Acute myeloid leukemia (AML) is an aggressive hematologic neoplasm, and patients with an internal tandem duplication (ITD) mutation of the FMS-like tyrosine kinase-3 (FLT3) receptor gene have a poor prognosis. FLT3-ITD interacts with DOCK2, a G effector protein that activates Rac1/2. Previously, we showed that knockdown of DOCK2 leads to decreased survival of FLT3-ITD leukemic cells. We further investigated the mechanisms by which Rac1/DOCK2 activity affects cell survival and chemotherapeutic response in FLT3-ITD leukemic cells. Exogenous expression of FLT3-ITD led to increased Rac1 activity, reactive oxygen species, phosphorylated STAT5, DNA damage response factors and cytarabine resistance. Conversely, DOCK2 knockdown resulted in a decrease in these factors. Consistent with the reduction in DNA damage response factors, FLT3-ITD cells with DOCK2 knockdown exhibited significantly increased sensitivity to DNA damage response inhibitors. Moreover, in a mouse model of FLT3-ITD AML, animals treated with the CHK1 inhibitor MK8776 + cytarabine survived longer than those treated with cytarabine alone. These findings suggest that FLT3-ITD and Rac1 activity cooperatively modulate DNA repair activity, the addition of DNA damage response inhibitors to conventional chemotherapy may be useful in the treatment of FLT3-ITD AML, and inhibition of the Rac signaling pathways via DOCK2 may provide a novel and promising therapeutic target for FLT3-ITD AML.
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Affiliation(s)
| | - Li Li
- Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins Hospital, Baltimore, Maryland, USA
| | | | - Donald Small
- Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins Hospital, Baltimore, Maryland, USA
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Knudsen JR, Henriquez-Olguin C, Li Z, Jensen TE. Electroporated GLUT4-7myc-GFP detects in vivo glucose transporter 4 translocation in skeletal muscle without discernible changes in GFP patterns. Exp Physiol 2019; 104:704-714. [PMID: 30710396 DOI: 10.1113/ep087545] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 02/01/2019] [Indexed: 12/22/2022]
Abstract
NEW FINDINGS What is the central question of this study? Resolving the mechanism(s) leading to glucose transporter 4 (GLUT4) translocation to the muscle surface membrane has great therapeutic potential. However, the measurement of GLUT4 translocation is technically challenging. Here, we asked whether electroporation of GLUT4-7myc-GFP into skeletal muscle could be used as a tool to study GLUT4 translocation in vivo. What is the main finding and its importance? By acutely inducing GLUT4-7myc-GFP expression in skeletal muscle, we verified that in vivo exercise and AICAR stimulation increased the GLUT4 presence in the sarcolemma measured as myc signal. Importantly, the increased myc signal in the sarcolemma was not accompanied by major visual changes in the distribution of the GFP signal. ABSTRACT Insulin and exercise lead to translocation of the glucose transporter 4 (GLUT4) to the surface membrane of skeletal muscle fibres. This process is pivotal for facilitating glucose uptake into skeletal muscle. To study this, a robust assay is needed to measure the translocation of GLUT4 in adult skeletal muscle directly. Here, we aimed to validate a simple GLUT4 translocation assay using a genetically encoded biosensor in mouse skeletal muscle. We transfected GLUT4-7myc-GFP into mouse muscle to study live GLUT4 movement and to evaluate GLUT4 insertion in the muscle surface membrane after in vivo running exercise and pharmacological activation of AMP-activated protein kinase (AMPK). Transfection led to expression of GLUT4-7myc-GFP that was dynamic in live flexor digitorum brevis fibres and which, upon insulin stimulation, exposed the myc epitope extracellularly. Running exercise, in addition to AMPK activation by 5-aminoimidazole-4-carboxamide ribonucleotide, induced ∼125 and ∼100% increase, respectively, in extracellularly exposure of GLUT4 in the surface membrane of tibialis anterior muscle. Interestingly, the clear increase in surface-exposed GLUT4 content induced by insulin, exercise or AMPK activation was not accompanied by any discernible reorganization of the GLUT4-GFP signal. In conclusion, we provide a detailed description of an easy-to-use translocation assay to study GLUT4 accumulation at the surface membrane induced by exercise and exercise-mimicking stimuli. Notably, our analyses revealed that increased GLUT4 surface membrane accumulation was not accompanied by a discernible change in the GLUT4 localization pattern.
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Affiliation(s)
- Jonas Roland Knudsen
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Carlos Henriquez-Olguin
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Zhencheng Li
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Thomas Elbenhardt Jensen
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
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58
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Yaribeygi H, Atkin SL, Simental‐Mendía LE, Sahebkar A. Molecular mechanisms by which aerobic exercise induces insulin sensitivity. J Cell Physiol 2019; 234:12385-12392. [DOI: 10.1002/jcp.28066] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 12/18/2018] [Indexed: 12/14/2022]
Affiliation(s)
- Habib Yaribeygi
- Chronic Kidney Disease Research Center, Shahid Beheshti University of Medical Sciences Tehran Iran
| | | | | | - Amirhossein Sahebkar
- Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences Mashhad Iran
- Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences Mashhad Iran
- School of Pharmacy, Mashhad University of Medical Sciences Mashhad Iran
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59
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Marko DM, Shamshoum H. Rac1 supports muscle glucose uptake independently of Akt. J Physiol 2018; 596:4815-4816. [PMID: 30160315 DOI: 10.1113/jp276851] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Daniel M Marko
- Department of Health Sciences, Brock University, St Catharines, ON, L2S 3A1, Canada
| | - Hesham Shamshoum
- Department of Health Sciences, Brock University, St Catharines, ON, L2S 3A1, Canada
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60
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Hutt DM, Loguercio S, Campos AR, Balch WE. A Proteomic Variant Approach (ProVarA) for Personalized Medicine of Inherited and Somatic Disease. J Mol Biol 2018; 430:2951-2973. [PMID: 29924966 PMCID: PMC6097907 DOI: 10.1016/j.jmb.2018.06.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 06/07/2018] [Accepted: 06/08/2018] [Indexed: 12/21/2022]
Abstract
The advent of precision medicine for genetic diseases has been hampered by the large number of variants that cause familial and somatic disease, a complexity that is further confounded by the impact of genetic modifiers. To begin to understand differences in onset, progression and therapeutic response that exist among disease-causing variants, we present the proteomic variant approach (ProVarA), a proteomic method that integrates mass spectrometry with genomic tools to dissect the etiology of disease. To illustrate its value, we examined the impact of variation in cystic fibrosis (CF), where 2025 disease-associated mutations in the CF transmembrane conductance regulator (CFTR) gene have been annotated and where individual genotypes exhibit phenotypic heterogeneity and response to therapeutic intervention. A comparative analysis of variant-specific proteomics allows us to identify a number of protein interactions contributing to the basic defects associated with F508del- and G551D-CFTR, two of the most common disease-associated variants in the patient population. We demonstrate that a number of these causal interactions are significantly altered in response to treatment with Vx809 and Vx770, small-molecule therapeutics that respectively target the F508del and G551D variants. ProVarA represents the first comparative proteomic analysis among multiple disease-causing mutations, thereby providing a methodological approach that provides a significant advancement to existing proteomic efforts in understanding the impact of variation in CF disease. We posit that the implementation of ProVarA for any familial or somatic mutation will provide a substantial increase in the knowledge base needed to implement a precision medicine-based approach for clinical management of disease.
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Affiliation(s)
- Darren M Hutt
- The Scripps Research Institute, Department of Molecular Medicine, 10550 North Torrey Pines Rd, La Jolla CA USA 92037
| | - Salvatore Loguercio
- The Scripps Research Institute, Department of Molecular Medicine, 10550 North Torrey Pines Rd, La Jolla CA USA 92037
| | - Alexandre Rosa Campos
- Sanford Burnham Prebys Medical Discovery Institute Proteomic Core 10901 North Torrey Pines Road, La Jolla CA USA 92037
| | - William E Balch
- The Scripps Research Institute, Department of Molecular Medicine, 10550 North Torrey Pines Rd, La Jolla CA USA 92037
- Integrative Structural and Computational Biology, 10550 North Torrey Pines Rd, La Jolla CA USA 92037
- The Skaggs Institute for Chemical Biology, 10550 North Torrey Pines Rd, La Jolla CA USA 92037
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Hargreaves M, Spriet LL. Exercise Metabolism: Fuels for the Fire. Cold Spring Harb Perspect Med 2018; 8:cshperspect.a029744. [PMID: 28533314 DOI: 10.1101/cshperspect.a029744] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
During exercise, the supply of adenosine triphosphate (ATP) is essential for the energy-dependent processes that underpin ongoing contractile activity. These pathways involve both substrate-level phosphorylation, without any need for oxygen, and oxidative phosphorylation that is critically dependent on oxygen delivery to contracting skeletal muscle by the respiratory and cardiovascular systems and on the supply of reducing equivalents from the degradation of carbohydrate, fat, and, to a limited extent, protein fuel stores. The relative contribution of these pathways is primarily determined by exercise intensity, but also modulated by training status, preceding diet, age, gender, and environmental conditions. Optimal substrate availability and utilization before, during, and after exercise is critical for maintaining exercise performance. This review provides a brief overview of exercise metabolism, with expanded discussion of the regulation of muscle glucose uptake and fatty acid uptake and oxidation.
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Affiliation(s)
- Mark Hargreaves
- Department of Physiology, The University of Melbourne, Victoria 3010, Australia
| | - Lawrence L Spriet
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada
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Madsen AB, Knudsen JR, Henriquez-Olguin C, Angin Y, Zaal KJ, Sylow L, Schjerling P, Ralston E, Jensen TE. β-Actin shows limited mobility and is required only for supraphysiological insulin-stimulated glucose transport in young adult soleus muscle. Am J Physiol Endocrinol Metab 2018; 315. [PMID: 29533739 PMCID: PMC6087721 DOI: 10.1152/ajpendo.00392.2017] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Studies in skeletal muscle cell cultures suggest that the cortical actin cytoskeleton is a major requirement for insulin-stimulated glucose transport, implicating the β-actin isoform, which in many cell types is the main actin isoform. However, it is not clear that β-actin plays such a role in mature skeletal muscle. Neither dependency of glucose transport on β-actin nor actin reorganization upon glucose transport have been tested in mature muscle. To investigate the role of β-actin in fully differentiated muscle, we performed a detailed characterization of wild type and muscle-specific β-actin knockout (KO) mice. The effects of the β-actin KO were subtle; however, we confirmed the previously reported decline in running performance of β-actin KO mice compared with wild type during repeated maximal running tests. We also found insulin-stimulated glucose transport into incubated muscles reduced in soleus but not in extensor digitorum longus muscle of young adult mice. Contraction-stimulated glucose transport trended toward the same pattern, but the glucose transport phenotype disappeared in soleus muscles from mature adult mice. No genotype-related differences were found in body composition or glucose tolerance or by indirect calorimetry measurements. To evaluate β-actin mobility in mature muscle, we electroporated green fluorescent protein (GFP)-β-actin into flexor digitorum brevis muscle fibers and measured fluorescence recovery after photobleaching. GFP-β-actin showed limited unstimulated mobility and no changes after insulin stimulation. In conclusion, β-actin is not required for glucose transport regulation in mature mouse muscle under the majority of the tested conditions. Thus, our work reveals fundamental differences in the role of the cortical β-actin cytoskeleton in mature muscle compared with cell culture.
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Affiliation(s)
- Agnete B Madsen
- Department of Nutrition, Exercise and Sports, University of Copenhagen , Copenhagen , Denmark
| | - Jonas R Knudsen
- Department of Nutrition, Exercise and Sports, University of Copenhagen , Copenhagen , Denmark
| | - Carlos Henriquez-Olguin
- Department of Nutrition, Exercise and Sports, University of Copenhagen , Copenhagen , Denmark
- Centro de Estudios Moleculares de la Célula, Instituto de Ciencias Biomédicas, Universidad de Chile ; Laboratory of Exercise Sciences, Clínica MEDS, Santiago , Chile
| | - Yeliz Angin
- Department of Nutrition, Exercise and Sports, University of Copenhagen , Copenhagen , Denmark
| | - Kristien J Zaal
- Light Imaging Section, Office of Science and Technology, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health , Bethesda, Maryland
| | - Lykke Sylow
- Department of Nutrition, Exercise and Sports, University of Copenhagen , Copenhagen , Denmark
| | - Peter Schjerling
- Institute of Sports Medicine, Department of Orthopedic Surgery, Bispebjerg Hospital , Copenhagen , Denmark
- Center of Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen , Copenhagen , Denmark
| | - Evelyn Ralston
- Light Imaging Section, Office of Science and Technology, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health , Bethesda, Maryland
| | - Thomas E Jensen
- Department of Nutrition, Exercise and Sports, University of Copenhagen , Copenhagen , Denmark
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Raun SH, Ali M, Kjøbsted R, Møller LLV, Federspiel MA, Richter EA, Jensen TE, Sylow L. Rac1 muscle knockout exacerbates the detrimental effect of high-fat diet on insulin-stimulated muscle glucose uptake independently of Akt. J Physiol 2018; 596:2283-2299. [PMID: 29749029 DOI: 10.1113/jp275602] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 03/19/2018] [Indexed: 12/17/2022] Open
Abstract
KEY POINTS The actin cytoskeleton regulating GTPase, Rac1, is a novel player in insulin-stimulated glucose uptake in muscle in vivo. High-fat diet (HFD) exacerbates muscle insulin resistance in Rac1 muscle knockout (mKO) mice. Muscle Rac1 KO protects against HFD-induced insulin resistance in fat tissue indicating tissue cross-talk. A fatty diet markedly reduces insulin clearance in mice. ABSTRACT Insulin resistance and perturbations in glucose metabolism underpin common lifestyle diseases such as type 2 diabetes and obesity. Insulin resistance in muscle is characterized by compromised activity of the GTPase, Ras-related C3 Botulinum toxin substrate 1 (Rac1), yet the role of Rac1 in insulin-stimulated glucose uptake in vivo and diet-induced insulin resistance is unknown. Inducible muscle-specific Rac1 knockout (Rac1 mKO) and wild type (WT) littermate mice were either fed a chow or a 60% high-fat diet (HFD). Insulin-stimulated 2-deoxy-glucose uptake, intracellular signalling, protein expression, substrate utilization, and glucose and insulin tolerance were assessed. In chow-fed mice, in vivo insulin-stimulated glucose uptake was reduced in triceps, soleus and gastrocnemius muscles from Rac1 mKO mice. HFD-induced whole body insulin resistance was exacerbated by the lack of muscle Rac1 and glucose uptake was reduced in all muscles, except for soleus. Muscle Akt (also known as protein kinase B) signalling was unaffected by diet or genotype. In adipose tissue, Rac1 mKO mice were protected from HFD-induced insulin resistance (with respect to both glucose uptake and phosphorylated-Akt), rendering their whole body glucose tolerance comparable to WT mice on HFD. Our findings show that lack of Rac1 exacerbates HFD-induced insulin resistance in skeletal muscle. Whole body glucose tolerance, however, was largely unaffected in Rac1 mKO mice, likely due to improved insulin-stimulated glucose uptake in adipose tissue. We conclude that lack of Rac1 in the context of obesity is detrimental to insulin-stimulated muscle glucose uptake in muscle independently of Akt signalling.
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Affiliation(s)
- Steffen H Raun
- Molecular Physiology Group, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Universitetsparken 13, Copenhagen, 2100, Denmark
| | - Mona Ali
- Molecular Physiology Group, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Universitetsparken 13, Copenhagen, 2100, Denmark
| | - Rasmus Kjøbsted
- Molecular Physiology Group, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Universitetsparken 13, Copenhagen, 2100, Denmark
| | - Lisbeth L V Møller
- Molecular Physiology Group, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Universitetsparken 13, Copenhagen, 2100, Denmark
| | - Morten A Federspiel
- Cell Biology and Physiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Erik A Richter
- Molecular Physiology Group, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Universitetsparken 13, Copenhagen, 2100, Denmark
| | - Thomas E Jensen
- Molecular Physiology Group, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Universitetsparken 13, Copenhagen, 2100, Denmark
| | - Lykke Sylow
- Molecular Physiology Group, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Universitetsparken 13, Copenhagen, 2100, Denmark
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Li Z, Yue Y, Hu F, Zhang C, Ma X, Li N, Qiu L, Fu M, Chen L, Yao Z, Bilan PJ, Klip A, Niu W. Electrical pulse stimulation induces GLUT4 translocation in C 2C 12 myotubes that depends on Rab8A, Rab13, and Rab14. Am J Physiol Endocrinol Metab 2018; 314:E478-E493. [PMID: 29089333 DOI: 10.1152/ajpendo.00103.2017] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The signals mobilizing GLUT4 to the plasma membrane in response to muscle contraction are less known than those elicited by insulin. This disparity is undoubtedly due to lack of suitable in vitro models to study skeletal muscle contraction. We generated C2C12 myotubes stably expressing HA-tagged GLUT4 (C2C12-GLUT4 HA) that contract in response to electrical pulse stimulation (EPS) and investigated molecular mechanisms regulating GLUT4 HA. EPS (60 min, 20 V, 1 Hz, 24-ms pulses at 976-ms intervals) elicited a gain in surface GLUT4 HA (GLUT4 translocation) comparably to insulin or 5-amino imidazole-4-carboxamide ribonucleotide (AICAR). A myosin II inhibitor prevented EPS-stimulated myotube contraction and reduced surface GLUT4 by 56%. EPS stimulated AMPK and CaMKII phosphorylation, and EPS-stimulated GLUT4 translocation was reduced in part by small interfering (si)RNA-mediated AMPKα1/α2 knockdown, compound C, siRNA-mediated Ca2+/calmodulin-dependent protein kinase (CaMKII)δ knockdown, or CaMKII inhibitor KN93. Key regulatory residues on the Rab-GAPs AS160 and TBC1D1 were phosphorylated in response to EPS. Stable expression of an activated form of the Rab-GAP AS160 (AS160-4A) diminished EPS- and insulin-stimulated GLUT4 translocation, suggesting regulation of GLUT4 vesicle traffic by Rab GTPases. Knockdown of each Rab8a, Rab13, or Rab14 reduced, in part, GLUT4 translocation induced by EPS, whereas only Rab8a, or Rab14 knockdown reduced the AICAR response. In conclusion, EPS involves Rab8a, Rab13, and Rab14 to elicit GLUT4 translocation but not Rab10; moreover, Rab10 and Rab13 are not engaged by AMPK activation alone. C2C12-GLUT4 HA cultures constitute a valuable in vitro model to investigate molecular mechanisms of contraction-stimulated GLUT4 translocation.
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Affiliation(s)
- Zhu Li
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Key Laboratory of Hormones and Development (Ministry of Health), Tianjin Metabolic Diseases Hospital, Tianjin Medical University , Tianjin , China
| | - Yingying Yue
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Key Laboratory of Hormones and Development (Ministry of Health), Tianjin Metabolic Diseases Hospital, Tianjin Medical University , Tianjin , China
| | - Fang Hu
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Key Laboratory of Hormones and Development (Ministry of Health), Tianjin Metabolic Diseases Hospital, Tianjin Medical University , Tianjin , China
| | - Chang Zhang
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Key Laboratory of Hormones and Development (Ministry of Health), Tianjin Metabolic Diseases Hospital, Tianjin Medical University , Tianjin , China
| | - Xiaofang Ma
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Key Laboratory of Hormones and Development (Ministry of Health), Tianjin Metabolic Diseases Hospital, Tianjin Medical University , Tianjin , China
- Central Laboratory, The Fifth Central Hospital of Tianjin , Tianjin , China
| | - Nana Li
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Key Laboratory of Hormones and Development (Ministry of Health), Tianjin Metabolic Diseases Hospital, Tianjin Medical University , Tianjin , China
| | - Lihong Qiu
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Key Laboratory of Hormones and Development (Ministry of Health), Tianjin Metabolic Diseases Hospital, Tianjin Medical University , Tianjin , China
| | - Maolong Fu
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Key Laboratory of Hormones and Development (Ministry of Health), Tianjin Metabolic Diseases Hospital, Tianjin Medical University , Tianjin , China
- Tianjin Third Central Hospital , Tianjin , China
| | - Liming Chen
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Key Laboratory of Hormones and Development (Ministry of Health), Tianjin Metabolic Diseases Hospital, Tianjin Medical University , Tianjin , China
| | - Zhi Yao
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Key Laboratory of Hormones and Development (Ministry of Health), Tianjin Metabolic Diseases Hospital, Tianjin Medical University , Tianjin , China
| | - Philip J Bilan
- Cell Biology Program, The Hospital for Sick Children , Toronto, Ontario , Canada
| | - Amira Klip
- Cell Biology Program, The Hospital for Sick Children , Toronto, Ontario , Canada
| | - Wenyan Niu
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Key Laboratory of Hormones and Development (Ministry of Health), Tianjin Metabolic Diseases Hospital, Tianjin Medical University , Tianjin , China
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Tsuchiya M, Sekiai S, Hatakeyama H, Koide M, Chaweewannakorn C, Yaoita F, Tan-No K, Sasaki K, Watanabe M, Sugawara S, Endo Y, Itoi E, Hagiwara Y, Kanzaki M. Neutrophils Provide a Favorable IL-1-Mediated Immunometabolic Niche that Primes GLUT4 Translocation and Performance in Skeletal Muscles. Cell Rep 2018; 23:2354-2364. [DOI: 10.1016/j.celrep.2018.04.067] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 03/09/2018] [Accepted: 04/14/2018] [Indexed: 11/27/2022] Open
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Hu F, Li N, Li Z, Zhang C, Yue Y, Liu Q, Chen L, Bilan PJ, Niu W. Electrical pulse stimulation induces GLUT4 translocation in a Rac-Akt-dependent manner in C2C12 myotubes. FEBS Lett 2018; 592:644-654. [PMID: 29355935 DOI: 10.1002/1873-3468.12982] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 01/07/2018] [Accepted: 01/15/2018] [Indexed: 12/12/2022]
Abstract
Muscle contraction increases skeletal muscle glucose uptake, but the underlying mechanisms are not fully elucidated. While important for insulin-stimulated glucose uptake, the role of Akt in contraction-stimulated muscle glucose uptake is controversial. In our study, C2C12 skeletal muscle myotubes were contracted by electrical pulse stimulation (EPS). We found that EPS leads to Akt phosphorylation on sites S473 and T308 in a time-dependent manner. The Akt inhibitor MK2206 partly reduces EPS-stimulated GLUT4 translocation without affecting EPS-stimulated AMPK phosphorylation. EPS activates Rac1 GTP-binding, and EPS-stimulated GLUT4 translocation is partly inhibited by Rac1 inhibitor II and siRac1. Interestingly, both Rac1 inhibitor II and siRac1 inhibit EPS-stimulated Akt phosphorylation on sites S473 and T308. Our findings implicate a Rac1-Akt signaling pathway in EPS-stimulated GLUT4 translocation in C2C12 myotubes.
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Affiliation(s)
- Fang Hu
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Metabolic Diseases Hospital, Tianjin Medical University, China
| | - Nana Li
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Metabolic Diseases Hospital, Tianjin Medical University, China
| | - Zhu Li
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Metabolic Diseases Hospital, Tianjin Medical University, China
| | - Chang Zhang
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Metabolic Diseases Hospital, Tianjin Medical University, China
| | - Yingying Yue
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Metabolic Diseases Hospital, Tianjin Medical University, China
| | - Qian Liu
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Metabolic Diseases Hospital, Tianjin Medical University, China
| | - Liming Chen
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Metabolic Diseases Hospital, Tianjin Medical University, China
| | - Philip J Bilan
- Cell Biology Program, The Hospital for Sick Children, Toronto, ON, Canada
| | - Wenyan Niu
- Department of Immunology, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Metabolic Diseases Hospital, Tianjin Medical University, China
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Cardama GA, Alonso DF, Gonzalez N, Maggio J, Gomez DE, Rolfo C, Menna PL. Relevance of small GTPase Rac1 pathway in drug and radio-resistance mechanisms: Opportunities in cancer therapeutics. Crit Rev Oncol Hematol 2018; 124:29-36. [PMID: 29548483 DOI: 10.1016/j.critrevonc.2018.01.012] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 11/21/2017] [Accepted: 01/31/2018] [Indexed: 10/18/2022] Open
Abstract
Rac1 GTPase signaling pathway has a critical role in the regulation of a plethora of cellular functions governing cancer cell behavior. Recently, it has been shown a critical role of Rac1 in the emergence of resistance mechanisms to cancer therapy. This review describes the current knowledge regarding Rac1 pathway deregulation and its association with chemoresistance, radioresistance, resistance to targeted therapies and immune evasion. This supports the idea that interfering Rac1 signaling pathway could be an interesting approach to tackle cancer resistance.
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Affiliation(s)
- G A Cardama
- Laboratory of Molecular Oncology, National University of Quilmes, Buenos Aires, Argentina
| | - D F Alonso
- Laboratory of Molecular Oncology, National University of Quilmes, Buenos Aires, Argentina; National Council of Scientific and Technical Research (CONICET), Buenos Aires, Argentina
| | - N Gonzalez
- Laboratory of Molecular Oncology, National University of Quilmes, Buenos Aires, Argentina
| | - J Maggio
- Laboratory of Molecular Oncology, National University of Quilmes, Buenos Aires, Argentina
| | - D E Gomez
- Laboratory of Molecular Oncology, National University of Quilmes, Buenos Aires, Argentina; National Council of Scientific and Technical Research (CONICET), Buenos Aires, Argentina
| | - C Rolfo
- Phase I-Early Clinical trials Unit, Oncology Department Antwerp University Hospital & Center for Oncological Research (CORE), Antwerp University, Belgium.
| | - P L Menna
- Laboratory of Molecular Oncology, National University of Quilmes, Buenos Aires, Argentina; National Council of Scientific and Technical Research (CONICET), Buenos Aires, Argentina
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Jaldin-Fincati JR, Bilan PJ, Klip A. GLUT4 Translocation in Single Muscle Cells in Culture: Epitope Detection by Immunofluorescence. Methods Mol Biol 2018; 1713:175-192. [PMID: 29218526 DOI: 10.1007/978-1-4939-7507-5_14] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
GLUT4 is the major glucose transporter in skeletal muscle. GLUT4 cycles to and from the plasma membrane and its exocytic rate is accelerated by insulin and muscle contraction to achieve a new steady state with more GLUT4 proteins at the muscle cell surface. To gain a better understanding of the molecular and cellular mechanisms that govern GLUT4 protein recycling, we developed an in vitro model in which myc-epitope-tagged GLUT4 or GLUT4-GFP is expressed in L6 skeletal muscle cells. The myc-epitope is inserted into an exofacial domain that is accessible to anti-myc antibodies from the outside of non-permeabilized cells, allowing one to count the number of transporters at the cell surface. This enables one to perform single-cell analysis using confocal fluorescence microscopy to quantify cell surface GLUT4myc or GLUT4myc-GFP in cells co-transfected with diverse cDNA constructs, treated with siRNAs, or co-stained with antibodies for other proteins of interest. Herein, we describe the methodology to perform these experimental approaches in insulin-stimulated L6 muscle cells.
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Affiliation(s)
- Javier R Jaldin-Fincati
- Cell Biology Program, Research Institute, The Hospital for Sick Children, 686 Bay Street, PGCRL, Room 19.9709, Toronto, ON, Canada, M5G 0A4
| | - Philip J Bilan
- Cell Biology Program, Research Institute, The Hospital for Sick Children, 686 Bay Street, PGCRL, Room 19.9709, Toronto, ON, Canada, M5G 0A4
| | - Amira Klip
- Cell Biology Program, Research Institute, The Hospital for Sick Children, 686 Bay Street, PGCRL, Room 19.9709, Toronto, ON, Canada, M5G 0A4.
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69
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Peppler WT, MacPherson REK. Rac1 is a novel regulator of exercise-induced glucose uptake. J Physiol 2018; 594:7155-7156. [PMID: 27976403 DOI: 10.1113/jp272929] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Willem T Peppler
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Rebecca E K MacPherson
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
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70
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Jaldin-Fincati JR, Pavarotti M, Frendo-Cumbo S, Bilan PJ, Klip A. Update on GLUT4 Vesicle Traffic: A Cornerstone of Insulin Action. Trends Endocrinol Metab 2017; 28:597-611. [PMID: 28602209 DOI: 10.1016/j.tem.2017.05.002] [Citation(s) in RCA: 180] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 05/08/2017] [Accepted: 05/09/2017] [Indexed: 12/20/2022]
Abstract
Glucose transport is rate limiting for dietary glucose utilization by muscle and fat. The glucose transporter GLUT4 is dynamically sorted and retained intracellularly and redistributes to the plasma membrane (PM) by insulin-regulated vesicular traffic, or 'GLUT4 translocation'. Here we emphasize recent findings in GLUT4 translocation research. The application of total internal reflection fluorescence microscopy (TIRFM) has increased our understanding of insulin-regulated events beneath the PM, such as vesicle tethering and membrane fusion. We describe recent findings on Akt-targeted Rab GTPase-activating proteins (GAPs) (TBC1D1, TBC1D4, TBC1D13) and downstream Rab GTPases (Rab8a, Rab10, Rab13, Rab14, and their effectors) along with the input of Rac1 and actin filaments, molecular motors [myosinVa (MyoVa), myosin1c (Myo1c), myosinIIA (MyoIIA)], and membrane fusion regulators (syntaxin4, munc18c, Doc2b). Collectively these findings reveal novel events in insulin-regulated GLUT4 traffic.
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Affiliation(s)
| | - Martin Pavarotti
- Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5J 2L4, Canada; IHEM, Universidad Nacional de Cuyo, CONICET, Mendoza 5500, Argentina
| | - Scott Frendo-Cumbo
- Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5J 2L4, Canada; Department of Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Philip J Bilan
- Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5J 2L4, Canada
| | - Amira Klip
- Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5J 2L4, Canada; Department of Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada.
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71
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Molecular mechanisms of ROS production and oxidative stress in diabetes. Biochem J 2017; 473:4527-4550. [PMID: 27941030 DOI: 10.1042/bcj20160503c] [Citation(s) in RCA: 528] [Impact Index Per Article: 75.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 10/07/2016] [Accepted: 10/10/2016] [Indexed: 12/18/2022]
Abstract
Oxidative stress and chronic inflammation are known to be associated with the development of metabolic diseases, including diabetes. Oxidative stress, an imbalance between oxidative and antioxidative systems of cells and tissues, is a result of over production of oxidative-free radicals and associated reactive oxygen species (ROS). One outcome of excessive levels of ROS is the modification of the structure and function of cellular proteins and lipids, leading to cellular dysfunction including impaired energy metabolism, altered cell signalling and cell cycle control, impaired cell transport mechanisms and overall dysfunctional biological activity, immune activation and inflammation. Nutritional stress, such as that caused by excess high-fat and/or carbohydrate diets, promotes oxidative stress as evident by increased lipid peroxidation products, protein carbonylation and decreased antioxidant status. In obesity, chronic oxidative stress and associated inflammation are the underlying factors that lead to the development of pathologies such as insulin resistance, dysregulated pathways of metabolism, diabetes and cardiovascular disease through impaired signalling and metabolism resulting in dysfunction to insulin secretion, insulin action and immune responses. However, exercise may counter excessive levels of oxidative stress and thus improve metabolic and inflammatory outcomes. In the present article, we review the cellular and molecular origins and significance of ROS production, the molecular targets and responses describing how oxidative stress affects cell function including mechanisms of insulin secretion and action, from the point of view of possible application of novel diabetic therapies based on redox regulation.
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Kleinert M, Parker BL, Fritzen AM, Knudsen JR, Jensen TE, Kjøbsted R, Sylow L, Ruegg M, James DE, Richter EA. Mammalian target of rapamycin complex 2 regulates muscle glucose uptake during exercise in mice. J Physiol 2017; 595:4845-4855. [PMID: 28464351 DOI: 10.1113/jp274203] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 04/26/2017] [Indexed: 01/04/2023] Open
Abstract
KEY POINTS Exercise is a potent physiological stimulus to clear blood glucose from the circulation into skeletal muscle. The mammalian target of rapamycin complex 2 (mTORC2) is an important regulator of muscle glucose uptake in response to insulin stimulation. Here we report for the first time that the activity of mTORC2 in mouse muscle increases during exercise. We further show that glucose uptake during exercise is decreased in mouse muscle that lacks mTORC2 activity. We also provide novel identifications of new mTORC2 substrates during exercise in mouse muscle. ABSTRACT Exercise increases glucose uptake into insulin-resistant muscle. Thus, elucidating the exercise signalling network in muscle may uncover new therapeutic targets. The mammalian target of rapamycin complex 2 (mTORC2), a regulator of insulin-controlled glucose uptake, has been reported to interact with ras-related C3 botulinum toxin substrate 1 (Rac1), which plays a role in exercise-induced glucose uptake in muscle. Therefore, we tested the hypothesis that mTORC2 activity is necessary for muscle glucose uptake during treadmill exercise. We used mice that specifically lack mTORC2 signalling in muscle by deletion of the obligatory mTORC2 component Rictor (Ric mKO). Running capacity and running-induced changes in blood glucose, plasma lactate and muscle glycogen levels were similar in wild-type (Ric WT) and Ric mKO mice. At rest, muscle glucose uptake was normal, but during running muscle glucose uptake was reduced by 40% in Ric mKO mice compared to Ric WT mice. Running increased muscle phosphorylated 5' AMP-activated protein kinase (AMPK) similarly in Ric WT and Ric mKO mice, and glucose transporter type 4 (GLUT4) and hexokinase II (HKII) protein expressions were also normal in Ric mKO muscle. The mTORC2 substrate, phosphorylated protein kinase C α (PKCα), and the mTORC2 activity readout, phosphorylated N-myc downstream regulated 1 (NDRG1) protein increased with running in Ric WT mice, but were not altered by running in Ric mKO muscle. Quantitative phosphoproteomics uncovered several additional potential exercise-dependent mTORC2 substrates, including contractile proteins, kinases, transcriptional regulators, actin cytoskeleton regulators and ion-transport proteins. Our study suggests that mTORC2 is a component of the exercise signalling network that regulates muscle glucose uptake and we provide a resource of new potential members of the mTORC2 signalling network.
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Affiliation(s)
- Maximilian Kleinert
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark.,Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, Germany
| | - Benjamin L Parker
- Charles Perkins Centre, School of Life and Environmental Science, The University of Sydney, Sydney, Australia
| | - Andreas M Fritzen
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Jonas R Knudsen
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Thomas E Jensen
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Rasmus Kjøbsted
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Lykke Sylow
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Markus Ruegg
- Biozentrum, University of Basel, Basel, Switzerland
| | - David E James
- Charles Perkins Centre, School of Life and Environmental Science, The University of Sydney, Sydney, Australia.,Sydney Medical School, The University of Sydney, Sydney, Australia
| | - Erik A Richter
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
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Sylow L, Møller LLV, Kleinert M, D'Hulst G, De Groote E, Schjerling P, Steinberg GR, Jensen TE, Richter EA. Rac1 and AMPK Account for the Majority of Muscle Glucose Uptake Stimulated by Ex Vivo Contraction but Not In Vivo Exercise. Diabetes 2017; 66:1548-1559. [PMID: 28389470 DOI: 10.2337/db16-1138] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 03/15/2017] [Indexed: 11/13/2022]
Abstract
Exercise bypasses insulin resistance to increase glucose uptake in skeletal muscle and therefore represents an important alternative to stimulate glucose uptake in insulin-resistant muscle. Both Rac1 and AMPK have been shown to partly regulate contraction-stimulated muscle glucose uptake, but whether those two signaling pathways jointly account for the entire signal to glucose transport is unknown. We therefore studied the ability of contraction and exercise to stimulate glucose transport in isolated muscles with AMPK loss of function combined with either pharmacological inhibition or genetic deletion of Rac1.Muscle-specific knockout (mKO) of Rac1, a kinase-dead α2 AMPK (α2KD), and double knockout (KO) of β1 and β2 AMPK subunits (β1β2 KO) each partially decreased contraction-stimulated glucose transport in mouse soleus and extensor digitorum longus (EDL) muscle. Interestingly, when pharmacological Rac1 inhibition was combined with either AMPK β1β2 KO or α2KD, contraction-stimulated glucose transport was almost completely inhibited. Importantly, α2KD+Rac1 mKO double-transgenic mice also displayed severely impaired contraction-stimulated glucose transport, whereas exercise-stimulated glucose uptake in vivo was only partially reduced by Rac1 mKO with no additive effect of α2KD. It is concluded that Rac1 and AMPK together account for almost the entire ex vivo contraction response in muscle glucose transport, whereas only Rac1, but not α2 AMPK, regulates muscle glucose uptake during submaximal exercise in vivo.
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Affiliation(s)
- Lykke Sylow
- Molecular Physiology Group, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Lisbeth L V Møller
- Molecular Physiology Group, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Maximilian Kleinert
- Molecular Physiology Group, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Gommaar D'Hulst
- Department of Kinesiology, Exercise Physiology Research Group, Faculty of Kinesiology and Rehabilitation Sciences, KU Leuven, Leuven, Belgium
| | | | - Peter Schjerling
- Institute of Sports Medicine, Department of Orthopedic Surgery, Bispebjerg Hospital, Copenhagen, Denmark
- Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Gregory R Steinberg
- Division of Endocrinology and Metabolism, Department of Medicine and Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Thomas E Jensen
- Molecular Physiology Group, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Erik A Richter
- Molecular Physiology Group, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
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74
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Sylow L, Kleinert M, Richter EA, Jensen TE. Exercise-stimulated glucose uptake - regulation and implications for glycaemic control. Nat Rev Endocrinol 2017; 13:133-148. [PMID: 27739515 DOI: 10.1038/nrendo.2016.162] [Citation(s) in RCA: 265] [Impact Index Per Article: 37.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Skeletal muscle extracts glucose from the blood to maintain demand for carbohydrates as an energy source during exercise. Such uptake involves complex molecular signalling processes that are distinct from those activated by insulin. Exercise-stimulated glucose uptake is preserved in insulin-resistant muscle, emphasizing exercise as a therapeutic cornerstone among patients with metabolic diseases such as diabetes mellitus. Exercise increases uptake of glucose by up to 50-fold through the simultaneous stimulation of three key steps: delivery, transport across the muscle membrane and intracellular flux through metabolic processes (glycolysis and glucose oxidation). The available data suggest that no single signal transduction pathway can fully account for the regulation of any of these key steps, owing to redundancy in the signalling pathways that mediate glucose uptake to ensure maintenance of muscle energy supply during physical activity. Here, we review the molecular mechanisms that regulate the movement of glucose from the capillary bed into the muscle cell and discuss what is known about their integrated regulation during exercise. Novel developments within the field of mass spectrometry-based proteomics indicate that the known regulators of glucose uptake are only the tip of the iceberg. Consequently, many exciting discoveries clearly lie ahead.
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Affiliation(s)
- Lykke Sylow
- Molecular Physiology Group, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Maximilian Kleinert
- Molecular Physiology Group, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
- Institute for Diabetes and Obesity, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Erik A Richter
- Molecular Physiology Group, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Thomas E Jensen
- Molecular Physiology Group, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
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75
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Tunduguru R, Thurmond DC. Promoting Glucose Transporter-4 Vesicle Trafficking along Cytoskeletal Tracks: PAK-Ing Them Out. Front Endocrinol (Lausanne) 2017; 8:329. [PMID: 29209279 PMCID: PMC5701999 DOI: 10.3389/fendo.2017.00329] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 11/06/2017] [Indexed: 12/27/2022] Open
Abstract
Glucose is the principal cellular energy source in humans and maintenance of glucose homeostasis is critical for survival. Glucose uptake into peripheral skeletal muscle and adipose tissues requires the trafficking of vesicles containing glucose transporter-4 (GLUT4) from the intracellular storage compartments to the cell surface. Trafficking of GLUT4 storage vesicles is initiated via the canonical insulin signaling cascade in skeletal muscle and fat cells, as well as via exercise-induced contraction in muscle cells. Recent studies have elucidated steps in the signaling cascades that involve remodeling of the cytoskeleton, a process that underpins the mechanical movement of GLUT4 vesicles. This review is focused upon an alternate phosphoinositide-3 kinase-dependent pathway involving Ras-related C3 botulinum toxin substrate 1 signaling through the p21-activated kinase p21-activated kinase 1 and showcases related signaling events that co-regulate both the depolymerization and re-polymerization of filamentous actin. These new insights provide an enriched understanding into the process of glucose transport and yield potential new targets for interventions aimed to improve insulin sensitivity and remediate insulin resistance, pre-diabetes, and the progression to type 2 diabetes.
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Affiliation(s)
- Ragadeepthi Tunduguru
- Department of Molecular and Cellular Endocrinology, Diabetes and Metabolism Research Institute of City of Hope, Duarte, CA, United States
| | - Debbie C. Thurmond
- Department of Molecular and Cellular Endocrinology, Diabetes and Metabolism Research Institute of City of Hope, Duarte, CA, United States
- *Correspondence: Debbie C. Thurmond,
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Parker L, Shaw CS, Stepto NK, Levinger I. Exercise and Glycemic Control: Focus on Redox Homeostasis and Redox-Sensitive Protein Signaling. Front Endocrinol (Lausanne) 2017; 8:87. [PMID: 28529499 PMCID: PMC5418238 DOI: 10.3389/fendo.2017.00087] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 04/04/2017] [Indexed: 12/16/2022] Open
Abstract
Physical inactivity, excess energy consumption, and obesity are associated with elevated systemic oxidative stress and the sustained activation of redox-sensitive stress-activated protein kinase (SAPK) and mitogen-activated protein kinase signaling pathways. Sustained SAPK activation leads to aberrant insulin signaling, impaired glycemic control, and the development and progression of cardiometabolic disease. Paradoxically, acute exercise transiently increases oxidative stress and SAPK signaling, yet postexercise glycemic control and skeletal muscle function are enhanced. Furthermore, regular exercise leads to the upregulation of antioxidant defense, which likely assists in the mitigation of chronic oxidative stress-associated disease. In this review, we explore the complex spatiotemporal interplay between exercise, oxidative stress, and glycemic control, and highlight exercise-induced reactive oxygen species and redox-sensitive protein signaling as important regulators of glucose homeostasis.
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Affiliation(s)
- Lewan Parker
- Institute of Sport, Exercise and Active Living (ISEAL), College of Sport and Exercise Science, Victoria University, Melbourne, VIC, Australia
- *Correspondence: Lewan Parker, ,
| | - Christopher S. Shaw
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Geelong, VIC, Australia
| | - Nigel K. Stepto
- Institute of Sport, Exercise and Active Living (ISEAL), College of Sport and Exercise Science, Victoria University, Melbourne, VIC, Australia
- Monash Centre for Health Research and Implementation, School of Public Health and Preventative Medicine, Monash University, Clayton, VIC, Australia
- Australian Institute for Musculoskeletal Science (AIMSS), Victoria University and Western Health, St. Albans, VIC, Australia
| | - Itamar Levinger
- Institute of Sport, Exercise and Active Living (ISEAL), College of Sport and Exercise Science, Victoria University, Melbourne, VIC, Australia
- Australian Institute for Musculoskeletal Science (AIMSS), Victoria University and Western Health, St. Albans, VIC, Australia
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77
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Zhou X, Shentu P, Xu Y. Spatiotemporal Regulators for Insulin-Stimulated GLUT4 Vesicle Exocytosis. J Diabetes Res 2017; 2017:1683678. [PMID: 28529958 PMCID: PMC5424486 DOI: 10.1155/2017/1683678] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 03/21/2017] [Accepted: 04/03/2017] [Indexed: 11/30/2022] Open
Abstract
Insulin increases glucose uptake and storage in muscle and adipose cells, which is accomplished through the mobilization of intracellular GLUT4 storage vesicles (GSVs) to the cell surface upon stimulation. Importantly, the dysfunction of insulin-regulated GLUT4 trafficking is strongly linked with peripheral insulin resistance and type 2 diabetes in human. The insulin signaling pathway, key signaling molecules involved, and precise trafficking itinerary of GSVs are largely identified. Understanding the interaction between insulin signaling molecules and key regulatory proteins that are involved in spatiotemporal regulation of GLUT4 vesicle exocytosis is of great importance to explain the pathogenesis of diabetes and may provide new potential therapeutic targets.
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Affiliation(s)
- Xiaoxu Zhou
- Department of Biomedical Engineering, Key Laboratory for Biomedical Engineering of Ministry of Education, Zhejiang Provincial Key Laboratory of Cardio-Cerebral Vascular Detection Technology and Medicinal Effectiveness Appraisal, Zhejiang University, Hangzhou 310027, China
| | - Ping Shentu
- Department of Biomedical Engineering, Key Laboratory for Biomedical Engineering of Ministry of Education, Zhejiang Provincial Key Laboratory of Cardio-Cerebral Vascular Detection Technology and Medicinal Effectiveness Appraisal, Zhejiang University, Hangzhou 310027, China
| | - Yingke Xu
- Department of Biomedical Engineering, Key Laboratory for Biomedical Engineering of Ministry of Education, Zhejiang Provincial Key Laboratory of Cardio-Cerebral Vascular Detection Technology and Medicinal Effectiveness Appraisal, Zhejiang University, Hangzhou 310027, China
- *Yingke Xu:
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78
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Teich T, Riddell MC. The Enhancement of Muscle Insulin Sensitivity After Exercise: A Rac1-Independent Handoff to Some Other Player? Endocrinology 2016; 157:2999-3001. [PMID: 27477862 DOI: 10.1210/en.2016-1453] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Trevor Teich
- School of Kinesiology and Health Science (T.T., M.C.R.), Muscle Health Research Centre, York University, Toronto, Ontario, Canada M3J 1P3; and LMC Diabetes and Endocrinology (M.C.R.), Toronto, Ontario, Canada M4G 3E8
| | - Michael C Riddell
- School of Kinesiology and Health Science (T.T., M.C.R.), Muscle Health Research Centre, York University, Toronto, Ontario, Canada M3J 1P3; and LMC Diabetes and Endocrinology (M.C.R.), Toronto, Ontario, Canada M4G 3E8
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79
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Li W, Liang X, Zeng Z, Yu K, Zhan S, Su Q, Yan Y, Mansai H, Qiao W, Yang Q, Qi Z, Huang Z. Simvastatin inhibits glucose uptake activity and GLUT4 translocation through suppression of the IR/IRS-1/Akt signaling in C2C12 myotubes. Biomed Pharmacother 2016; 83:194-200. [PMID: 27470565 DOI: 10.1016/j.biopha.2016.06.029] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Revised: 05/17/2016] [Accepted: 06/16/2016] [Indexed: 12/24/2022] Open
Abstract
Simvastatin,a 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase inhibitor, is clinically used in the prevention and treatment of cardiovascular diseases. Numerous studies demonstrate that statins increase the risk of new-onset diabetes in long-term therapy, but mechanisms underpinning this effect are still unclear. Here, we investigated whether simvastatin inhibited the glucose uptake activity and the underlying mechanisms in C2C12 myotubes. Our studies showed that simvastatin significantly inhibited glucose uptake activity and GLUT4 translocation, whereas the effect was reversible with mevalonolactone (ML), which acts as an intermediate of cholesterol synthesis pathway. Mechanistically, the inhibition of glucose uptake and GLUT4 translocation elicited by simvastatin were associated with the suppression of the insulin receptor (IR)/IR substrate (IRS)/Akt signaling cascade. Simvastatin suppressed the phosphorylation of IR, IRS-1 and Akt, and total expression of IR or IRS-1, but did not affect Akt. Furthermore, simvastatin decreased Rac1 GTP binding. In conclusion, our findings indicate that simvastatin suppresses glucose uptake activity and GLUT4 translocation via IR-dependent IRS-1/PI3K/Akt pathway. These results provide an important new insight into the mechanism of statins on insulin sensitivity which may be associated with new-onset diabetes.
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Affiliation(s)
- Weihua Li
- Department of Cardiology, the First Affiliated Hospital of Xiamen University, Xiamen City, Fujian Province, China
| | - Xiaojing Liang
- Department of Cardiology, the First Affiliated Hospital of Xiamen University, Xiamen City, Fujian Province, China
| | - Zhipeng Zeng
- Department of Cardiology, the First Affiliated Hospital of Xiamen University, Xiamen City, Fujian Province, China; Laboratory of Cardiovascular Immunology, Key Laboratory of Biological Targeted Therapy of the Ministry of Education, Institute of Cardiology, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Kaizhen Yu
- Department of Cardiology, the First Affiliated Hospital of Xiamen University, Xiamen City, Fujian Province, China
| | - Shaopeng Zhan
- Department of Cardiology, the First Affiliated Hospital of Xiamen University, Xiamen City, Fujian Province, China
| | - Qiang Su
- Department of Cardiology, the First Affiliated Hospital of Xiamen University, Xiamen City, Fujian Province, China
| | - Yinzhi Yan
- Department of Cardiology, the First Affiliated Hospital of Xiamen University, Xiamen City, Fujian Province, China
| | - Huseen Mansai
- Department of Cardiology, the First Affiliated Hospital of Xiamen University, Xiamen City, Fujian Province, China
| | - Weitong Qiao
- Department of Cardiology, the First Affiliated Hospital of Xiamen University, Xiamen City, Fujian Province, China
| | - Qi Yang
- Department of Cardiology, the First Affiliated Hospital of Xiamen University, Xiamen City, Fujian Province, China
| | - Zhongquan Qi
- Organ Transplantation Institute, Medical College, Xiamen University, Xiamen City, Fujian Province, China.
| | - Zhengrong Huang
- Department of Cardiology, the First Affiliated Hospital of Xiamen University, Xiamen City, Fujian Province, China.
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