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Bowman PRT, Smith GL, Gould GW. Run for your life: can exercise be used to effectively target GLUT4 in diabetic cardiac disease? PeerJ 2021; 9:e11485. [PMID: 34113491 PMCID: PMC8162245 DOI: 10.7717/peerj.11485] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Accepted: 04/27/2021] [Indexed: 12/25/2022] Open
Abstract
The global incidence, associated mortality rates and economic burden of diabetes are now such that it is considered one of the most pressing worldwide public health challenges. Considerable research is now devoted to better understanding the mechanisms underlying the onset and progression of this disease, with an ultimate aim of improving the array of available preventive and therapeutic interventions. One area of particular unmet clinical need is the significantly elevated rate of cardiomyopathy in diabetic patients, which in part contributes to cardiovascular disease being the primary cause of premature death in this population. This review will first consider the role of metabolism and more specifically the insulin sensitive glucose transporter GLUT4 in diabetic cardiac disease, before addressing how we may use exercise to intervene in order to beneficially impact key functional clinical outcomes.
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Affiliation(s)
- Peter R T Bowman
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
| | - Godfrey L Smith
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Gwyn W Gould
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
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2
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Proskocil BJ, Calco GN, Nie Z. Insulin acutely increases agonist-induced airway smooth muscle contraction in humans and rats. Am J Physiol Lung Cell Mol Physiol 2021; 320:L545-L556. [PMID: 33501891 DOI: 10.1152/ajplung.00232.2020] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Obesity increases incidence and severity of asthma but the molecular mechanisms are not completely understood. Hyperinsulinemia potentiates vagally induced bronchoconstriction in obese rats. Since bronchoconstriction results from airway smooth muscle contraction, we tested whether insulin changed agonist-induced airway smooth muscle contraction. Obesity-prone and resistant rats were fed a low-fat diet for 5 wk and treated with insulin (Lantus, 3 units/rat sc) 16 h before vagally induced bronchoconstriction was measured. Ex vivo, contractile responses to methacholine were measured in isolated rat tracheal rings and human airway smooth muscle strips before and after incubation (0.5-2 h) with 100 nM insulin or 13.1 nM insulin like growth factor-1 (IGF-1). M2 and M3 muscarinic receptor mRNA expression was quantified by qRT-PCR and changes in intracellular calcium were measured in response to methacholine or serotonin in isolated rat tracheal smooth muscle cells treated with 1 µM insulin. Insulin, administered to animals 16 h prior, potentiated vagally induced bronchoconstriction in both obese-prone and resistant rats. Insulin, not IGF-1, significantly increased methacholine-induced contraction of rat and human isolated airway smooth muscle. In cultured rat tracheal smooth muscle cells, insulin significantly increased M2, not M3, mRNA expression and enhanced methacholine- and serotonin-induced increase in intracellular calcium. Insulin alone did not cause an immediate increase in intracellular calcium. Thus, insulin acutely potentiated agonist-induced increase in intracellular calcium and airway smooth muscle contraction. These findings may explain why obese individuals with hyperinsulinemia are prone to airway hyperreactivity and give insights into future targets for asthma treatment.
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Affiliation(s)
- Becky J Proskocil
- Division of Pulmonary and Critical Care Medicine, Oregon Health & Science University, Portland, Oregon
| | - Gina N Calco
- Division of Pulmonary and Critical Care Medicine, Oregon Health & Science University, Portland, Oregon
| | - Zhenying Nie
- Division of Pulmonary and Critical Care Medicine, Oregon Health & Science University, Portland, Oregon
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3
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Kakizawa S, Kishimoto Y, Yamamoto S, Onga K, Yasuda K, Miyamoto Y, Watanabe M, Sakai R, Mori N. Functional maintenance of calcium store by ShcB adaptor protein in cerebellar Purkinje cells. Sci Rep 2020; 10:14475. [PMID: 32879382 PMCID: PMC7468156 DOI: 10.1038/s41598-020-71414-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Accepted: 08/14/2020] [Indexed: 11/15/2022] Open
Abstract
Intracellular Ca2+ levels are changed by influx from extracellular medium and release from intracellular stores. In the central nervous systems, Ca2+ release is involved in various physiological events, such as neuronal excitability and transmitter release. Although stable Ca2+ release in response to stimulus is critical for proper functions of the nervous systems, regulatory mechanisms relating to Ca2+ release are not fully understood in central neurons. Here, we demonstrate that ShcB, an adaptor protein expressed in central neurons, has an essential role in functional maintenance of Ca2+ store in cerebellar Purkinje cells (PCs). ShcB-knockout (KO) mice showed defects in cerebellar-dependent motor function and long-term depression (LTD) at cerebellar synapse. The reduced LTD was accompanied with an impairment of intracellular Ca2+ release. Although the expression of Ca2+ release channels and morphology of Ca2+ store looked intact, content of intracellular Ca2+ store and activity of sarco/endoplasmic reticular Ca2+-ATPase (SERCA) were largely decreased in the ShcB-deficient cerebellum. Furthermore, when ShcB was ectopically expressed in the ShcB-KO PCs, the Ca2+ release and its SERCA-dependent component were restored. These data indicate that ShcB plays a key role in the functional maintenance of ER Ca2+ store in central neurons through regulation of SERCA activity.
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Affiliation(s)
- Sho Kakizawa
- Department of Anatomy and Neurobiology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8523, Japan. .,Department of Biological Chemistry, Graduate School of Pharmaceutical Science, Kyoto University, Sakyo-ku, Kyoto, 606-8501, Japan.
| | - Yasushi Kishimoto
- Department of Biophysics, Kagawa School of Pharmaceutical Sciences, Tokushima Bunri University, Sanuki, Kagawa, 769-2193, Japan
| | - Shinichiro Yamamoto
- Department of Biological Chemistry, Graduate School of Pharmaceutical Science, Kyoto University, Sakyo-ku, Kyoto, 606-8501, Japan.,Division of Pharmacology, Faculty of Pharmaceutical Sciences, Teikyo Heisei University, Nakano-ku, Tokyo, 164-8530, Japan
| | - Kazuko Onga
- Department of Anatomy and Neurobiology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8523, Japan
| | - Kunihiko Yasuda
- Department of Anatomy and Neurobiology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8523, Japan.,Department of Occupational Therapy, Faculty of Fukuoka Medical Technology, Teikyo University, Omuta, 836-8505, Japan
| | - Yoshiaki Miyamoto
- Department of Pharmaceutical Therapy and Neuropharmacology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, 930-0194, Japan
| | - Masahiko Watanabe
- Department of Anatomy, Hokkaido University School of Medicine, Sapporo, 060-8638, Japan
| | - Ryuichi Sakai
- Department of Biochemistry, Kitasato University School of Medicine, Sagamihara, Kanagawa, 252-0373, Japan
| | - Nozomu Mori
- Department of Anatomy and Neurobiology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8523, Japan. .,Faculty of Medicine, Fukuoka International University of Health and Welfare, Fukuoka, 814-0001, Japan.
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4
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Sarcoplasmic reticulum and calcium signaling in muscle cells: Homeostasis and disease. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2020; 350:197-264. [PMID: 32138900 DOI: 10.1016/bs.ircmb.2019.12.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The sarco/endoplasmic reticulum is an extensive, dynamic and heterogeneous membranous network that fulfills multiple homeostatic functions. Among them, it compartmentalizes, stores and releases calcium within the intracellular space. In the case of muscle cells, calcium released from the sarco/endoplasmic reticulum in the vicinity of the contractile machinery induces cell contraction. Furthermore, sarco/endoplasmic reticulum-derived calcium also regulates gene transcription in the nucleus, energy metabolism in mitochondria and cytosolic signaling pathways. These diverse and overlapping processes require a highly complex fine-tuning that the sarco/endoplasmic reticulum provides by means of its numerous tubules and cisternae, specialized domains and contacts with other organelles. The sarco/endoplasmic reticulum also possesses a rich calcium-handling machinery, functionally coupled to both contraction-inducing stimuli and the contractile apparatus. Such is the importance of the sarco/endoplasmic reticulum for muscle cell physiology, that alterations in its structure, function or its calcium-handling machinery are intimately associated with the development of cardiometabolic diseases. Cardiac hypertrophy, insulin resistance and arterial hypertension are age-related pathologies with a common mechanism at the muscle cell level: the accumulation of damaged proteins at the sarco/endoplasmic reticulum induces a stress response condition termed endoplasmic reticulum stress, which impairs proper organelle function, ultimately leading to pathogenesis.
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Rivas Rios JR, Franchi F, Rollini F, Angiolillo DJ. Diabetes and antiplatelet therapy: from bench to bedside. Cardiovasc Diagn Ther 2018; 8:594-609. [PMID: 30498684 DOI: 10.21037/cdt.2018.05.09] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Diabetes mellitus (DM) is a metabolic disorder associated with accelerated atherogenesis and an increased risk of atherothrombotic complications. Multiple mechanisms contribute to the pro-thrombotic status which characterizes DM patients underscoring the importance of antiplatelet therapies used for secondary prevention in these patients. For many years, dual antiplatelet therapy (DAPT) with aspirin and the P2Y12 inhibitor clopidogrel has represented the mainstay of treatment following an acute coronary syndrome (ACS) or in patients undergoing percutaneous coronary interventions (PCI). Although DAPT reduces the incidence of atherothrombotic recurrences, these rates remain high in DM patients underscoring the need for more efficacious therapies. Oral platelet P2Y12 receptor inhibitors with enhanced potency, such as prasugrel and ticagrelor, as well as antiplatelet therapies such as vorapaxar inhibiting the thrombin-mediated platelet signaling pathway, constitute treatment opportunities for patients with DM and have shown to be associated with a greater reduction in ischemic recurrences, albeit at the cost of more bleeding. This article reviews currently available antiplatelet agents and delivers an update on the advances and drawbacks of these agents used for secondary prevention in DM patients experiencing an ACS or undergoing PCI.
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Affiliation(s)
- Jose R Rivas Rios
- Division of Cardiology, University of Florida College of Medicine-Jacksonville, Jacksonville, Florida, USA
| | - Francesco Franchi
- Division of Cardiology, University of Florida College of Medicine-Jacksonville, Jacksonville, Florida, USA
| | - Fabiana Rollini
- Division of Cardiology, University of Florida College of Medicine-Jacksonville, Jacksonville, Florida, USA
| | - Dominick J Angiolillo
- Division of Cardiology, University of Florida College of Medicine-Jacksonville, Jacksonville, Florida, USA
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Leggio M, Bendini M, Caldarone E, Lombardi M, Severi P, D’Emidio S, Stavri D, Armeni M, Bravi V, Mazza A. Low-dose aspirin for primary prevention of cardiovascular events in patients with diabetes: Benefit or risk? DIABETES & METABOLISM 2018; 44:217-225. [DOI: 10.1016/j.diabet.2017.11.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 09/05/2017] [Accepted: 11/05/2017] [Indexed: 01/13/2023]
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7
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Chawla B, Hedman AC, Sayedyahossein S, Erdemir HH, Li Z, Sacks DB. Absence of IQGAP1 Protein Leads to Insulin Resistance. J Biol Chem 2017; 292:3273-3289. [PMID: 28082684 DOI: 10.1074/jbc.m116.752642] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Revised: 01/10/2017] [Indexed: 11/06/2022] Open
Abstract
Insulin binds to the insulin receptor (IR) and induces tyrosine phosphorylation of the receptor and insulin receptor substrate-1 (IRS-1), leading to activation of the PKB/Akt and MAPK/ERK pathways. IQGAP1 is a scaffold protein that interacts with multiple binding partners and integrates diverse signaling cascades. Here we show that IQGAP1 associates with both IR and IRS-1 and influences insulin action. In vitro analysis with pure proteins revealed that the IQ region of IQGAP1 binds directly to the intracellular domain of IR. Similarly, the phosphotyrosine-binding domain of IRS-1 mediates a direct interaction with the C-terminal tail of IQGAP1. Consistent with these observations, both IR and IRS-1 co-immunoprecipitated with IQGAP1 from cells. Investigation of the functional effects of the interactions revealed that in the absence of IQGAP1, insulin-stimulated phosphorylation of Akt and ERK, as well as the association of phosphatidylinositol 3-kinase with IRS-1, were significantly decreased. Importantly, loss of IQGAP1 results in impaired insulin signaling and glucose homeostasis in vivo Collectively, these data reveal that IQGAP1 is a scaffold for IR and IRS-1 and implicate IQGAP1 as a participant in insulin signaling.
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Affiliation(s)
- Bhavna Chawla
- Department of Laboratory Medicine, National Institutes of Health, Bethesda, Maryland 20892
| | - Andrew C Hedman
- Department of Laboratory Medicine, National Institutes of Health, Bethesda, Maryland 20892
| | - Samar Sayedyahossein
- Department of Laboratory Medicine, National Institutes of Health, Bethesda, Maryland 20892
| | - Huseyin H Erdemir
- Department of Laboratory Medicine, National Institutes of Health, Bethesda, Maryland 20892
| | - Zhigang Li
- Department of Laboratory Medicine, National Institutes of Health, Bethesda, Maryland 20892
| | - David B Sacks
- Department of Laboratory Medicine, National Institutes of Health, Bethesda, Maryland 20892.
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8
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Capodanno D, Angiolillo DJ. Aspirin for Primary Cardiovascular Risk Prevention and Beyond in Diabetes Mellitus. Circulation 2016; 134:1579-1594. [PMID: 27729421 DOI: 10.1161/circulationaha.116.023164] [Citation(s) in RCA: 96] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 08/30/2016] [Indexed: 11/16/2022]
Abstract
Daily administration of low-dose aspirin has proved to be beneficial in preventing recurrent cardiovascular events. However, the role of aspirin for primary prevention in patients with no overt cardiovascular disease is more controversial. In fact, in lower risk patients, the modest benefit in reducing serious vascular events can be offset by the increased risk of bleeding, including intracranial and gastrointestinal hemorrhage. Diabetes mellitus has been associated with a substantially increased risk of both first and recurrent atherothrombotic events, which makes aspirin therapy of potential value in these subjects. Moving from general aspects of aspirin pharmacology and specific issues in diabetes mellitus, this article reviews the literature on the topic of aspirin for primary prevention in general, and in subjects with diabetes mellitus in particular, to culminate with arguments pro and con and a practical risk-based algorithm for aspirin initiation in daily practice.
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Affiliation(s)
- Davide Capodanno
- From Ferrarotto Hospital, University of Catania, Catania, Italy (D.C.); and University of Florida College of Medicine-Jacksonville (D.J.A.).
| | - Dominick J Angiolillo
- From Ferrarotto Hospital, University of Catania, Catania, Italy (D.C.); and University of Florida College of Medicine-Jacksonville (D.J.A.)
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9
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Tong X, Kono T, Anderson-Baucum EK, Yamamoto W, Gilon P, Lebeche D, Day RN, Shull GE, Evans-Molina C. SERCA2 Deficiency Impairs Pancreatic β-Cell Function in Response to Diet-Induced Obesity. Diabetes 2016; 65:3039-52. [PMID: 27489309 PMCID: PMC5033263 DOI: 10.2337/db16-0084] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Accepted: 07/28/2016] [Indexed: 12/18/2022]
Abstract
The sarcoendoplasmic reticulum (ER) Ca(2+) ATPase 2 (SERCA2) pump is a P-type ATPase tasked with the maintenance of ER Ca(2+) stores. Whereas β-cell SERCA2 expression is reduced in diabetes, the role of SERCA2 in the regulation of whole-body glucose homeostasis has remained uncharacterized. To this end, SERCA2 heterozygous mice (S2HET) were challenged with a high-fat diet (HFD) containing 45% of kilocalories from fat. After 16 weeks of the HFD, S2HET mice were hyperglycemic and glucose intolerant, but adiposity and insulin sensitivity were not different between HFD-fed S2HET mice and HFD-fed wild-type controls. Consistent with a defect in β-cell function, insulin secretion, glucose-induced cytosolic Ca(2+) mobilization, and the onset of steady-state glucose-induced Ca(2+) oscillations were impaired in HFD-fed S2HET islets. Moreover, HFD-fed S2HET mice exhibited reduced β-cell mass and proliferation, altered insulin production and proinsulin processing, and increased islet ER stress and death. In contrast, SERCA2 activation with a small molecule allosteric activator increased ER Ca(2+) storage and rescued tunicamycin-induced β-cell death. In aggregate, these data suggest a critical role for SERCA2 and the regulation of ER Ca(2+) homeostasis in the β-cell compensatory response to diet-induced obesity.
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Affiliation(s)
- Xin Tong
- Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, IN
| | - Tatsuyoshi Kono
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN
| | | | - Wataru Yamamoto
- Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, IN
| | - Patrick Gilon
- Pôle d'endocrinologie, diabète et nutrition, Institut de recherche expérimentale et clinique, Université catholique de Louvain, Brussels, Belgium
| | - Djamel Lebeche
- Cardiovascular Research Institute and Diabetes Obesity and Metabolism Institute, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Richard N Day
- Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, IN
| | - Gary E Shull
- Department of Molecular Genetics, Biochemistry, and Microbiology, University of Cincinnati College of Medicine, Cincinnati, OH
| | - Carmella Evans-Molina
- Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, IN Department of Medicine, Indiana University School of Medicine, Indianapolis, IN Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN Roudebush VA Medical Center, Indianapolis, IN
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Hakuno F, Fukushima T, Yoneyama Y, Kamei H, Ozoe A, Yoshihara H, Yamanaka D, Shibano T, Sone-Yonezawa M, Yu BC, Chida K, Takahashi SI. The Novel Functions of High-Molecular-Mass Complexes Containing Insulin Receptor Substrates in Mediation and Modulation of Insulin-Like Activities: Emerging Concept of Diverse Functions by IRS-Associated Proteins. Front Endocrinol (Lausanne) 2015; 6:73. [PMID: 26074875 PMCID: PMC4443775 DOI: 10.3389/fendo.2015.00073] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 04/25/2015] [Indexed: 12/25/2022] Open
Abstract
Insulin-like peptides, such as insulin-like growth factors (IGFs) and insulin, induce a variety of bioactivities, such as growth, differentiation, survival, increased anabolism, and decreased catabolism in many cell types and in vivo. In general, IGFs or insulin bind to IGF-I receptor (IGF-IR) or insulin receptor (IR), activating the receptor tyrosine kinase. Insulin receptor substrates (IRSs) are known to be major substrates of receptor kinases, mediating IGF/insulin signals to direct bioactivities. Recently, we discovered that IRSs form high-molecular-mass complexes (referred to here as IRSomes) even without IGF/insulin stimulation. These complexes contain proteins (referred to here as IRSAPs; IRS-associated proteins), which modulate tyrosine phosphorylation of IRSs by receptor kinases, control IRS stability, and determine intracellular localization of IRSs. In addition, in these complexes, we found not only proteins that are involved in RNA metabolism but also RNAs themselves. Thus, IRSAPs possibly contribute to modulation of IGF/insulin bioactivities. Since it is established that disorder of modulation of insulin-like activities causes various age-related diseases including cancer, we could propose that the IRSome is an important target for treatment of these diseases.
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Affiliation(s)
- Fumihiko Hakuno
- Department of Animal Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
- Department of Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Toshiaki Fukushima
- Laboratory of Biomedical Chemistry, Basic Life Sciences, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
- Department of Biological Sciences, Faculty of Bioscience and Biotechnology, Tokyo Institute of Technology, Kanagawa, Japan
| | - Yosuke Yoneyama
- Department of Animal Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
- Department of Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Hiroyasu Kamei
- Department of Animal Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
- Department of Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Atsufumi Ozoe
- Department of Animal Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
- Department of Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Hidehito Yoshihara
- Laboratory of Protein Metabolism, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Daisuke Yamanaka
- Department of Animal Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
- Department of Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Takashi Shibano
- Department of Animal Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
- Department of Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Meri Sone-Yonezawa
- Department of Animal Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
- Department of Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Bu-Chin Yu
- Department of Animal Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
- Department of Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Kazuhiro Chida
- Department of Animal Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
- Department of Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Shin-Ichiro Takahashi
- Department of Animal Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
- Department of Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
- *Correspondence: Shin-Ichiro Takahashi, Laboratory of Cell Regulation, Departments of Animal Sciences and Applied Biological Chemistry, Graduate School of Agriculture and Life Science, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan,
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11
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Regulation of SERCA pumps expression in diabetes. Cell Calcium 2014; 56:302-10. [DOI: 10.1016/j.ceca.2014.09.005] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Revised: 09/11/2014] [Accepted: 09/12/2014] [Indexed: 11/22/2022]
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12
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In vivo calcium regulation in diabetic skeletal muscle. Cell Calcium 2014; 56:381-9. [PMID: 25224503 DOI: 10.1016/j.ceca.2014.08.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2014] [Revised: 07/23/2014] [Accepted: 08/09/2014] [Indexed: 01/30/2023]
Abstract
In skeletal muscle, dysfunctional contractile activity has been linked to impaired intracellular Ca(2+) concentration ([Ca(2+)]i) regulation. Muscle force production is impaired and fatigability and muscle fragility deteriorate with diabetes. Use of a novel in vivo model permits investigation of [Ca(2+)]i homeostasis in diabetic skeletal muscle. Within this in vivo environment we have shown that diabetes perturbs the Ca(2+) regulatory system such that resting [Ca(2+)]i homeostasis following muscle contractions is compromised and elevations of [Ca(2+)]i are exacerbated. This review considers the impact of diabetes on the capacity of skeletal muscle to regulate [Ca(2+)]i, following muscle contractions and, in particular, the relationship between muscle fatigue and elevated [Ca(2+)]i in a highly ecologically relevant circulation-intact environment. Importantly, the role of mitochondria in calcium sequestration and the possibility that diabetes impacts this process is explored. Given the profound microcirculatory dysfunction in diabetes this preparation offers the unique opportunity to study the interrelationships among microvascular function, blood-myocyte oxygen flux and [Ca(2+)]i as they relate to enhanced muscle fatigability and exercise intolerance.
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Kubasov IV, Arutyunyan RS, Dobretsov MG, Shpakov AO, Matrosova EV. Effect of insulin on characteristics of contractile responses of fast and slow skeletal muscles of rats with acute streptozotocin-induced diabetes. J EVOL BIOCHEM PHYS+ 2014. [DOI: 10.1134/s0022093014020069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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14
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Harmer AR, Ruell PA, Hunter SK, McKenna MJ, Thom JM, Chisholm DJ, Flack JR. Effects of type 1 diabetes, sprint training and sex on skeletal muscle sarcoplasmic reticulum Ca2+ uptake and Ca2+-ATPase activity. J Physiol 2013; 592:523-35. [PMID: 24297852 DOI: 10.1113/jphysiol.2013.261172] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Calcium cycling is integral to muscle performance during the rapid muscle contraction and relaxation of high-intensity exercise. Ca(2+) handling is altered by diabetes mellitus, but has not previously been investigated in human skeletal muscle. We investigated effects of high-intensity exercise and sprint training on skeletal muscle Ca(2+) regulation among men and women with type 1 diabetes (T1D, n = 8, 3F, 5M) and matched non-diabetic controls (CON, n = 8, 3F, 5M). Secondarily, we examined sex differences in Ca(2+) regulation. Subjects undertook 7 weeks of three times-weekly cycle sprint training. Before and after training, performance was measured, and blood and muscle were sampled at rest and after high-intensity exercise. In T1D, higher Ca(2+)-ATPase activity (+28%) and Ca(2+) uptake (+21%) than in CON were evident across both times and days (P < 0.05), but performance was similar. In T1D, resting Ca(2+)-ATPase activity correlated with work performed until exhaustion (r = 0.7, P < 0.01). Ca(2+)-ATPase activity, but not Ca(2+) uptake, was lower (-24%, P < 0.05) among the women across both times and days. Intense exercise did not alter Ca(2+)-ATPase activity in T1D or CON. However, sex differences were evident: Ca(2+)-ATPase was reduced with exercise among men but increased among women across both days (time × sex interaction, P < 0.05). Sprint training reduced Ca(2+)-ATPase (-8%, P < 0.05), but not Ca(2+) uptake, in T1D and CON. In summary, skeletal muscle Ca(2+) resequestration capacity was increased in T1D, but performance was not greater than CON. Sprint training reduced Ca(2+)-ATPase in T1D and CON. Sex differences in Ca(2+)-ATPase activity were evident and may be linked with fibre type proportion differences.
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Affiliation(s)
- A R Harmer
- Clinical and Rehabilitation Sciences Research Group, Faculty of Health Sciences, The University of Sydney, PO Box 170, Lidcombe, NSW 1825, Australia.
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Abstract
Ca(2+)-ATPases (pumps) are key to the regulation of Ca(2+) in eukaryotic cells: nine are known today, belonging to three multigene families. The three endo(sarco)plasmic reticulum (SERCA) and the four plasma membrane (PMCA) pumps have been known for decades, the two Secretory Pathway Ca(2+) ATPase (SPCA) pumps have only become known recently. The number of pump isoforms is further increased by alternative splicing processes. The three pump types share the basic features of the catalytic mechanism, but differ in a number of properties related to tissue distribution, regulation, and role in the cellular homeostasis of Ca(2+). The molecular understanding of the function of all pumps has received great impetus from the solution of the three-dimensional (3D) structure of one of them, the SERCA pump. This landmark structural advance has been accompanied by the emergence and rapid expansion of the area of pump malfunction. Most of the pump defects described so far are genetic and produce subtler, often tissue and isoform specific, disturbances that affect individual components of the Ca(2+)-controlling and/or processing machinery, compellingly indicating a specialized role for each Ca(2+) pump type and/or isoform.
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Affiliation(s)
- Marisa Brini
- Department of Comparative Biomedicine and Food Science, University of Padova, Legnaro Padova, Italy.
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Su D, Shukla AK, Chen B, Kim JS, Nakayasu E, Qu Y, Aryal U, Weitz K, Clauss TR, Monroe ME, Camp DG, Bigelow DJ, Smith RD, Kulkarni RN, Qian WJ. Quantitative site-specific reactivity profiling of S-nitrosylation in mouse skeletal muscle using cysteinyl peptide enrichment coupled with mass spectrometry. Free Radic Biol Med 2013; 57:68-78. [PMID: 23277143 PMCID: PMC3771501 DOI: 10.1016/j.freeradbiomed.2012.12.010] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Revised: 11/12/2012] [Accepted: 12/13/2012] [Indexed: 12/18/2022]
Abstract
S-nitrosylation, the formation of S-nitrosothiol (SNO), is an important reversible thiol oxidation event that has been increasingly recognized for its role in cell signaling. Although many proteins susceptible to S-nitrosylation have been reported, site-specific identification of physiologically relevant SNO modifications remains an analytical challenge because of the low abundance and labile nature of this modification. Herein we present further improvement and optimization of the recently reported resin-assisted cysteinyl peptide enrichment protocol for SNO identification and its application to mouse skeletal muscle to identify specific cysteine sites sensitive to S-nitrosylation by a quantitative reactivity profiling strategy. Our results indicate that the protein- and peptide-level enrichment protocols provide comparable specificity and coverage of SNO-peptide identifications. S-nitrosylation reactivity profiling was performed by quantitatively comparing the site-specific SNO modification levels in samples treated with S-nitrosoglutathione, an NO donor, at two different concentrations (i.e., 10 and 100 μM). The reactivity profiling experiments led to the identification of 488 SNO-modified sites from 197 proteins with specificity of ∼95% at the unique peptide level, i.e., ∼95% of enriched peptides contain cysteine residues as the originally SNO-modified sites. Among these sites, 281 from 145 proteins were considered more sensitive to S-nitrosylation based on the ratios of observed SNO levels between the two treatments. These SNO-sensitive sites are more likely to be physiologically relevant. Many of the SNO-sensitive proteins are localized in mitochondria, contractile fiber, and actin cytoskeleton, suggesting the susceptibility of these subcellular compartments to redox regulation. Moreover, these observed SNO-sensitive proteins are primarily involved in metabolic pathways, including the tricarboxylic acid cycle, glycolysis/gluconeogenesis, glutathione metabolism, and fatty acid metabolism, suggesting the importance of redox regulation in muscle metabolism and insulin action.
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Affiliation(s)
- Dian Su
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Anil K. Shukla
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Baowei Chen
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Jong-Seo Kim
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Ernesto Nakayasu
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Yi Qu
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Uma Aryal
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Karl Weitz
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Therese R.W. Clauss
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Matthew E. Monroe
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - David G. Camp
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Diana J. Bigelow
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Richard D. Smith
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Rohit N. Kulkarni
- Joslin Diabetes Center, Harvard Medical School, Boston, MA 02215, USA
| | - Wei-Jun Qian
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
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Funai K, Song H, Yin L, Lodhi IJ, Wei X, Yoshino J, Coleman T, Semenkovich CF. Muscle lipogenesis balances insulin sensitivity and strength through calcium signaling. J Clin Invest 2013; 123:1229-40. [PMID: 23376793 DOI: 10.1172/jci65726] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Accepted: 12/14/2012] [Indexed: 12/24/2022] Open
Abstract
Exogenous dietary fat can induce obesity and promote diabetes, but endogenous fat production is not thought to affect skeletal muscle insulin resistance, an antecedent of metabolic disease. Unexpectedly, the lipogenic enzyme fatty acid synthase (FAS) was increased in the skeletal muscle of mice with diet-induced obesity and insulin resistance. Skeletal muscle-specific inactivation of FAS protected mice from insulin resistance without altering adiposity, specific inflammatory mediators of insulin signaling, or skeletal muscle levels of diacylglycerol or ceramide. Increased insulin sensitivity despite high-fat feeding was driven by activation of AMPK without affecting AMP content or the AMP/ATP ratio in resting skeletal muscle. AMPK was induced by elevated cytosolic calcium caused by impaired sarco/endoplasmic reticulum calcium ATPase (SERCA) activity due to altered phospholipid composition of the sarcoplasmic reticulum (SR), but came at the expense of decreased muscle strength. Thus, inhibition of skeletal muscle FAS prevents obesity-associated diabetes in mice, but also causes muscle weakness, which suggests that mammals have retained the capacity for lipogenesis in muscle to preserve physical performance in the setting of disrupted metabolic homeostasis.
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Affiliation(s)
- Katsuhiko Funai
- Division of Endocrinology, Metabolism and Lipid Research, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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Kavak S. Effects of Insulin on Altered Mechanical and Electrical Papillary Muscle Activities of Diabetic Rats. J Membr Biol 2012; 246:31-7. [DOI: 10.1007/s00232-012-9499-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Accepted: 08/18/2012] [Indexed: 10/27/2022]
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Fredersdorf S, Thumann C, Zimmermann WH, Vetter R, Graf T, Luchner A, Riegger GAJ, Schunkert H, Eschenhagen T, Weil J. Increased myocardial SERCA expression in early type 2 diabetes mellitus is insulin dependent: In vivo and in vitro data. Cardiovasc Diabetol 2012; 11:57. [PMID: 22621761 PMCID: PMC3447673 DOI: 10.1186/1475-2840-11-57] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Accepted: 05/02/2012] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Calcium (Ca2+) handling proteins are known to play a pivotal role in the pathophysiology of cardiomyopathy. However little is known about early changes in the diabetic heart and the impact of insulin treatment (Ins). METHODS Zucker Diabetic Fatty rats treated with or without insulin (ZDF ± Ins, n = 13) and lean littermates (controls, n = 7) were sacrificed at the age of 19 weeks. ZDF + Ins (n = 6) were treated with insulin for the last 6 weeks of life. Gene expression of Ca2+ ATPase in the cardiac sarcoplasmatic reticulum (SERCA2a, further abbreviated as SERCA) and phospholamban (PLB) were determined by northern blotting. Ca2+ transport of the sarcoplasmatic reticulum (SR) was assessed by oxalate-facilitated 45Ca-uptake in left ventricular homogenates. In addition, isolated neonatal cardiomyocytes were stimulated in cell culture with insulin, glucose or triiodthyronine (T3, positive control). mRNA expression of SERCA and PLB were measured by Taqman PCR. Furthermore, effects of insulin treatment on force of contraction and relaxation were evaluated by cardiomyocytes grown in a three-dimensional collagen matrix (engineered heart tissue, EHT) stimulated for 5 days by insulin. By western blot phosphorylations status of Akt was determed and the influence of wortmannin. RESULTS SERCA levels increased in both ZDF and ZDF + Ins compared to control (control 100 ± 6.2 vs. ZDF 152 ± 26.6* vs. ZDF + Ins 212 ± 18.5*# % of control, *p < 0.05 vs. control, #p < 0.05 vs. ZDF) whereas PLB was significantly decreased in ZDF and ZDF + Ins (control 100 ± 2.8 vs. ZDF 76.3 ± 13.5* vs. ZDF + Ins 79.4 ± 12.9* % of control, *p < 0.05 vs control). The increase in the SERCA/PLB ratio in ZDF and ZDF ± Ins was accompanied by enhanced Ca2+ uptake to the SR (control 1.58 ± 0.1 vs. ZDF 1.85 ± 0.06* vs. ZDF + Ins 2.03 ± 0.1* μg/mg/min, *p < 0.05 vs. control). Interestingly, there was a significant correlation between Ca2+ uptake and SERCA2a expression. As shown by in-vitro experiments, the effect of insulin on SERCA2a mRNA expression seemed to have a direct effect on cardiomyocytes. Furthermore, long-term treatment of engineered heart tissue with insulin increased the SERCA/PLB ratio and accelerated relaxation time. Akt was significantly phosphorylated by insulin. This effect could be abolished by wortmannin. CONCLUSION The current data demonstrate that early type 2 diabetes is associated with an increase in the SERCA/PLB ratio and that insulin directly stimulates SERCA expression and relaxation velocity. These results underline the important role of insulin and calcium handling proteins in the cardiac adaptation process of type 2 diabetes mellitus contributing to cardiac remodeling and show the important role of PI3-kinase-Akt-SERCA2a signaling cascade.
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MESH Headings
- Animals
- Animals, Newborn
- Blotting, Northern
- Blotting, Western
- Calcium/metabolism
- Calcium-Binding Proteins/genetics
- Calcium-Binding Proteins/metabolism
- Cells, Cultured
- Diabetes Mellitus, Type 2/blood
- Diabetes Mellitus, Type 2/drug therapy
- Diabetes Mellitus, Type 2/enzymology
- Diabetes Mellitus, Type 2/genetics
- Diabetes Mellitus, Type 2/physiopathology
- Disease Models, Animal
- Gene Expression Regulation, Enzymologic/drug effects
- Hypoglycemic Agents/pharmacology
- Insulin/pharmacology
- Male
- Myocardial Contraction/drug effects
- Myocardium/enzymology
- Myocytes, Cardiac/drug effects
- Myocytes, Cardiac/enzymology
- Phosphorylation
- Polymerase Chain Reaction
- Proto-Oncogene Proteins c-akt
- RNA, Messenger/metabolism
- Rats
- Rats, Wistar
- Rats, Zucker
- Sarcoplasmic Reticulum/enzymology
- Sarcoplasmic Reticulum Calcium-Transporting ATPases/genetics
- Sarcoplasmic Reticulum Calcium-Transporting ATPases/metabolism
- Time Factors
- Up-Regulation
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Affiliation(s)
- Sabine Fredersdorf
- Klinik und Poliklinik für Innere Medizin II, Universität Regensburg, Regensburg, Germany
- Klinik und Poliklinik für Innere Medizin II des Universitätsklinikums Regensburg, 93042, Regensburg, Germany
| | - Christian Thumann
- Klinik und Poliklinik für Innere Medizin II, Universität Regensburg, Regensburg, Germany
| | - Wolfram H Zimmermann
- Institut für Pharmakologie, Universitätsmedizin, Georg-August Universität Göttingen, Göttingen, Germany
| | - Roland Vetter
- Institut für Klinische Pharmakologie und Toxikologie, Universitätsmedizin - Berlin, Berlin, Germany
| | - Tobias Graf
- Medizinische Klinik II, Universitätsklinikum Schleswig-Holstein, Campus Lübeck, Lübeck, Germany
| | - Andreas Luchner
- Klinik und Poliklinik für Innere Medizin II, Universität Regensburg, Regensburg, Germany
| | - Günter AJ Riegger
- Klinik und Poliklinik für Innere Medizin II, Universität Regensburg, Regensburg, Germany
| | - Heribert Schunkert
- Medizinische Klinik II, Universitätsklinikum Schleswig-Holstein, Campus Lübeck, Lübeck, Germany
| | - Thomas Eschenhagen
- Institut für Klinische und Experimentelle Pharmakologie und Toxikologie, Universität Hamburg, Hamburg, Germany
| | - Joachim Weil
- Medizinische Klinik II, Universitätsklinikum Schleswig-Holstein, Campus Lübeck, Lübeck, Germany
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Affiliation(s)
- José Luis Ferreiro
- University of Florida College of Medicine-Jacksonville, 655 W 8th St., Jacksonville, FL 32209, USA
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21
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Abstract
Patients with diabetes mellitus (DM) have accelerated atherosclerosis, which is the main underlying factor contributing to the high risk of atherothrombotic events in these patients. Atherothrombotic complications are the leading cause of morbidity and mortality in patients with DM. Among factors contributing to the prothrombotic condition which characterise patients with DM, platelet hyperreactivity plays a pivotal role. Platelets of DM patients are characterised by dysregulation of several signalling pathways leading to intensified adhesion, activation and aggregation. Multiple mechanisms are involved in platelet dysfunction of patients with DM, which can be categorised as follows: a) hyperglycaemia, b) insulin deficiency and resistance, c) associated metabolic conditions, and d) other cellular abnormalities.The present manuscript aims to provide an overview on the current status of knowledge on platelet abnormalities that characterise patients with DM.
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Affiliation(s)
- José Luis Ferreiro
- IDIBELL-Hospital Universitari de Bellvitge, Department of Cardiology, Interventional Cardiology Unit, L'Hospitalet de Llobregat, Barcelona, Spain
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Abstract
The sarcoplasmic reticulum (SR) of smooth muscles presents many intriguing facets and questions concerning its roles, especially as these change with development, disease, and modulation of physiological activity. The SR's function was originally perceived to be synthetic and then that of a Ca store for the contractile proteins, acting as a Ca amplification mechanism as it does in striated muscles. Gradually, as investigators have struggled to find a convincing role for Ca-induced Ca release in many smooth muscles, a role in controlling excitability has emerged. This is the Ca spark/spontaneous transient outward current coupling mechanism which reduces excitability and limits contraction. Release of SR Ca occurs in response to inositol 1,4,5-trisphosphate, Ca, and nicotinic acid adenine dinucleotide phosphate, and depletion of SR Ca can initiate Ca entry, the mechanism of which is being investigated but seems to involve Stim and Orai as found in nonexcitable cells. The contribution of the elemental Ca signals from the SR, sparks and puffs, to global Ca signals, i.e., Ca waves and oscillations, is becoming clearer but is far from established. The dynamics of SR Ca release and uptake mechanisms are reviewed along with the control of luminal Ca. We review the growing list of the SR's functions that still includes Ca storage, contraction, and relaxation but has been expanded to encompass Ca homeostasis, generating local and global Ca signals, and contributing to cellular microdomains and signaling in other organelles, including mitochondria, lysosomes, and the nucleus. For an integrated approach, a review of aspects of the SR in health and disease and during development and aging are also included. While the sheer versatility of smooth muscle makes it foolish to have a "one model fits all" approach to this subject, we have tried to synthesize conclusions wherever possible.
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Affiliation(s)
- Susan Wray
- Department of Physiology, School of Biomedical Sciences, University of Liverpool, Liverpool, Merseyside L69 3BX, United Kingdom.
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Insulin Action in the Brain and the Pathogenesis of Alzheimer’s Disease. DIABETES, INSULIN AND ALZHEIMER'S DISEASE 2010. [DOI: 10.1007/978-3-642-04300-0_1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Vandecaetsbeek I, Raeymaekers L, Wuytack F, Vangheluwe P. Factors controlling the activity of the SERCA2a pump in the normal and failing heart. Biofactors 2009; 35:484-99. [PMID: 19904717 DOI: 10.1002/biof.63] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Heart failure is the leading cause of death in western countries and is often associated with impaired Ca(2+) handling in the cardiomyocyte. In fact, cardiomyocyte relaxation and contraction are tightly controlled by the activity of the cardiac sarco(endo)plasmic reticulum (ER/SR) Ca(2+) pump SERCA2a, pumping Ca(2+) from the cytosol into the lumen of the ER/SR. This review addresses three important facets that control the SERCA2 activity in the heart. First, we focus on the alternative splicing of the SERCA2 messenger, which is strictly regulated in the developing heart. This splicing controls the formation of three SERCA2 splice variants with different enzymatic properties. Second, we will discuss the role and regulation of SERCA2a activity in the normal and failing heart. The two well-studied Ca(2+) affinity modulators phospholamban and sarcolipin control the activity of SERCA2a within a narrow window. An aberrantly high or low Ca(2+) affinity is often observed in and may even trigger cardiac failure. Correcting SERCA2a activity might therefore constitute a therapeutic approach to improve the contractility of the failing heart. Finally, we address the controversies and unanswered questions of other putative regulators of the cardiac Ca(2+) pump, such as sarcalumenin, HRC, S100A1, Bcl-2, HAX-1, calreticulin, calnexin, ERp57, IRS-1, and -2.
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Affiliation(s)
- Ilse Vandecaetsbeek
- Department of Molecular Cell Biology, Laboratory of Ca(2+)-transport ATPases, K.U.Leuven, Leuven, Belgium
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25
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Abstract
Ca2+-ATPases (pumps) are key actors in the regulation of Ca2+ in eukaryotic cells and are thus essential to the correct functioning of the cell machinery. They have high affinity for Ca2+ and can efficiently regulate it down to very low concentration levels. Two of the pumps have been known for decades (the SERCA and PMCA pumps); one (the SPCA pump) has only become known recently. Each pump is the product of a multigene family, the number of isoforms being further increased by alternative splicing of the primary transcripts. The three pumps share the basic features of the catalytic mechanism but differ in a number of properties related to tissue distribution, regulation, and role in the cellular homeostasis of Ca2+. The molecular understanding of the function of the pumps has received great impetus from the solution of the three-dimensional structure of one of them, the SERCA pump. These spectacular advances in the structure and molecular mechanism of the pumps have been accompanied by the emergence and rapid expansion of the topic of pump malfunction, which has paralleled the rapid expansion of knowledge in the topic of Ca2+-signaling dysfunction. Most of the pump defects described so far are genetic: when they are very severe, they produce gross and global disturbances of Ca2+ homeostasis that are incompatible with cell life. However, pump defects may also be of a type that produce subtler, often tissue-specific disturbances that affect individual components of the Ca2+-controlling and/or processing machinery. They do not bring cells to immediate death but seriously compromise their normal functioning.
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Vangheluwe P, Sepúlveda MR, Missiaen L, Raeymaekers L, Wuytack F, Vanoevelen J. Intracellular Ca2+- and Mn2+-Transport ATPases. Chem Rev 2009; 109:4733-59. [DOI: 10.1021/cr900013m] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Peter Vangheluwe
- Laboratory of Ca2+-transport ATPases and Laboratory of Molecular and Cellular Signaling, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - M. Rosario Sepúlveda
- Laboratory of Ca2+-transport ATPases and Laboratory of Molecular and Cellular Signaling, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Ludwig Missiaen
- Laboratory of Ca2+-transport ATPases and Laboratory of Molecular and Cellular Signaling, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Luc Raeymaekers
- Laboratory of Ca2+-transport ATPases and Laboratory of Molecular and Cellular Signaling, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Frank Wuytack
- Laboratory of Ca2+-transport ATPases and Laboratory of Molecular and Cellular Signaling, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Jo Vanoevelen
- Laboratory of Ca2+-transport ATPases and Laboratory of Molecular and Cellular Signaling, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Leuven, Belgium
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27
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Affiliation(s)
| | - Ingrid Fleming
- From the Institute for Vascular Signalling, Johann Wolfgang Goethe University, Frankfurt am Main, Germany
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28
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Noble K, Matthew A, Burdyga T, Wray S. A review of recent insights into the role of the sarcoplasmic reticulum and Ca entry in uterine smooth muscle. Eur J Obstet Gynecol Reprod Biol 2009; 144 Suppl 1:S11-9. [PMID: 19285773 DOI: 10.1016/j.ejogrb.2009.02.010] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The uterine sacroplasmic reticulum (SR) takes up and stores calcium [Ca], using an ATPase (SERCA) and the Ca-buffering proteins, calsequestrin and calreticulin. This stored Ca can be released via IP(3)-gated Ca channels. Decreases in luminal Ca concentration [Ca] have been directly measured following agonist stimulation. During spontaneous contractions however, there appears to be no involvement of the SR, as Ca entry and efflux across the plasma membrane account for these phasic contractions. After over-viewing current knowledge concerning SR structure and function, we highlight three areas of research which suggest new ways of looking at the role of the SR in the uterus, although they may be controversial or speculative at the moment. Firstly, we review the evidence for the function, if any, of Ca-induced SR Ca release channels, the ryanodine receptor (RyR) and the lack of Ca sparks (the elemental release events from RyRs), in the uterus. Secondly, we ask does regulation of SERCA by the accessory protein, phospholamban, occur in the uterus and what is the effect of knocking out phospholamban on uterine activity? Thirdly, we address the question of when and how store-operated Ca entry occurs in the myometrium. By analogy with other, usually less excitable tissues, is there a mechanism that links store Ca depletion to plasma membrane Ca entry in smooth muscle cells within intact uterus and is it physiologically relevant and regulated? Are the recently described proteins ORAI and STIM-1 involved in uterine store-operated Ca entry? We end the review by integrating these new insights with previous data to present a new working model of the SR in the uterus.
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Affiliation(s)
- Karen Noble
- Department of Physiology, School of Biomedical Sciences, University of Liverpool, Crown Street, Liverpool L693BX, UK
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29
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Koricanac G, Milosavljevic T, Stojiljkovic M, Zakula Z, Tepavcevic S, Ribarac-Stepic N, Isenovic ER. Impact of estradiol on insulin signaling in the rat heart. Cell Biochem Funct 2009; 27:102-10. [DOI: 10.1002/cbf.1542] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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30
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Lebeche D, Davidoff AJ, Hajjar RJ. Interplay between impaired calcium regulation and insulin signaling abnormalities in diabetic cardiomyopathy. ACTA ACUST UNITED AC 2008; 5:715-24. [PMID: 18813212 DOI: 10.1038/ncpcardio1347] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2008] [Accepted: 07/30/2008] [Indexed: 02/06/2023]
Abstract
According to the International Diabetes Federation the number of people between the ages of 20 and 79 years diagnosed with diabetes mellitus is projected to reach 380 million worldwide by 2025. Cardiovascular disease, including heart failure, is the major cause of death in patients with diabetes. A contributing factor to heart failure in such patients is the development of diabetic cardiomyopathy--a clinical myocardial condition distinguished by ventricular dysfunction that can present independently of other risk factors such as hypertension or coronary artery disease. This disorder has been associated with both type 1 and type 2 diabetes, and is characterized by early-onset diastolic dysfunction and late-onset systolic dysfunction. The development of diabetic cardiomyopathy and the cellular and molecular perturbations associated with the pathology are complex and multifactorial. Hallmark mechanisms include abnormalities in regulation of calcium homeostasis, and associated abnormal ventricular excitation-contraction coupling, metabolic disturbances, and alterations in insulin signaling. An emerging concept is that disruptions in calcium homeostasis might be linked to diminished insulin responsiveness. An understanding of the cellular effect of these abnormalities on cardiomyocytes should be useful in predicting the maladaptive cardiac structural and functional consequences of diabetes.
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Affiliation(s)
- Djamel Lebeche
- Cardiovascular Research Center, Mount Sinai School of Medicine, New York, NY 10029, USA.
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31
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Vangheluwe P, Raeymaekers L, Dode L, Wuytack F. Modulating sarco(endo)plasmic reticulum Ca2+ ATPase 2 (SERCA2) activity: cell biological implications. Cell Calcium 2008; 38:291-302. [PMID: 16105684 DOI: 10.1016/j.ceca.2005.06.033] [Citation(s) in RCA: 157] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2005] [Accepted: 06/28/2005] [Indexed: 11/20/2022]
Abstract
Of the three mammalian members belonging to the sarco(endo)plasmic reticulum Ca2+ ATPase (SERCA) family, SERCA2 is evolutionary the oldest and shows the most wide tissue-expression pattern. Two major SERCA2 splice variants are well-characterized: the muscle-specific isoform SERCA2a and the housekeeping isoform SERCA2b. Recently, several interacting proteins and post-translational modifications of SERCA2 were identified which may modulate the activity of the Ca2+ pump. This review aims to give an overview of the vast literature concerning the cell biological implications of the SERCA2 isoform diversity and the factors regulating SERCA2. Proteins reported to interact with SERCA2 from the cytosolic domain involve the anti-apoptotic Bcl-2, the insulin receptor substrates IRS1/2, the EF-hand Ca2+-binding protein S100A1 and acylphosphatase. We will focus on the very particular position of SERCA2 as an enzyme functioning in a thin, highly fluid, leaky and cholesterol-poor membrane. Possible differential interactions of SERCA2b and SERCA2a with calreticulin, calnexin and ERp57, which could occur within the lumen of the endoplasmic reticulum will be discussed. Reported post-translational modifications possibly affecting pump activity involve N-glycosylation, glutathionylation and Ca2+/calmodulin kinase II-dependent phosphorylation. Finally, the pronounced vulnerability to oxidative damage of SERCA2 appears to be pivotal in the etiology of various pathologies.
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Affiliation(s)
- Peter Vangheluwe
- Laboratory of Physiology, O.&N. Gasthuisberg, K.U. Leuven, Campus Gasthuisberg, Herestraat 49, B-3000 Leuven, Belgium
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Dissection of the insulin signaling pathway via quantitative phosphoproteomics. Proc Natl Acad Sci U S A 2008; 105:2451-6. [PMID: 18268350 DOI: 10.1073/pnas.0711713105] [Citation(s) in RCA: 199] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The insulin signaling pathway is of pivotal importance in metabolic diseases, such as diabetes, and in cellular processes, such as aging. Insulin activates a tyrosine phosphorylation cascade that branches to create a complex network affecting multiple biological processes. To understand the full spectrum of the tyrosine phosphorylation cascade, we have defined the tyrosine-phosphoproteome of the insulin signaling pathway, using high resolution mass spectrometry in combination with phosphotyrosine immunoprecipitation and stable isotope labeling by amino acids in cell culture (SILAC) in differentiated brown adipocytes. Of 40 identified insulin-induced effectors, 7 have not previously been described in insulin signaling, including SDR, PKCdelta binding protein, LRP-6, and PISP/PDZK11, a potential calcium ATPase binding protein. A proteomic interaction screen with PISP/PDZK11 identified the calcium transporting ATPase SERCA2, supporting a connection to calcium signaling. The combination of quantitative phosphoproteomics with cell culture models provides a powerful strategy to dissect the insulin signaling pathways in intact cells.
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Ouwens DM, Diamant M. Myocardial insulin action and the contribution of insulin resistance to the pathogenesis of diabetic cardiomyopathy. Arch Physiol Biochem 2007; 113:76-86. [PMID: 17558606 DOI: 10.1080/13813450701422633] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Heart disease is the leading cause of death in patients with insulin resistance and type 2 diabetes (DM2). Even in the absence of coronary artery disease and hypertension, functional and structural abnormalities exist in patients with well-controlled and uncomplicated DM2. These derangements are collectively designated by the term diabetic cardiomyopathy (DCM). Changes in myocardial energy metabolism, due to altered substrate supply and utilization, largely underlie the development of DCM. Insulin is an important regulator of myocardial substrate metabolism, but also exerts regulatory effects on intracellular Ca2+ handling and cell survival. The current paper reviews the multiple functional and molecular effects of insulin on the heart, all of which ultimately seem to be cardioprotective both under normal conditions and under ischemia. In particular, the dismal consequences of myocardial insulin resistance contributing to the development of DCM will be discussed.
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Affiliation(s)
- D M Ouwens
- Department of Molecular Cell Biology, Leiden University Medical Centre, Leiden, The Netherlands.
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Nakipova OV, Andreeva LA, Zakharova NM, Semenova TP, Solomonov NG. Influence of wortmannin on the inotropic effect of insulin in papillary muscles of Siberian ground squirrel heart. DOKL BIOCHEM BIOPHYS 2006; 407:91-3. [PMID: 16776074 DOI: 10.1134/s1607672906020128] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- O V Nakipova
- Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino, Moscow oblast, 142290 Russia
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35
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Taniguchi CM, Emanuelli B, Kahn CR. Critical nodes in signalling pathways: insights into insulin action. Nat Rev Mol Cell Biol 2006; 7:85-96. [PMID: 16493415 DOI: 10.1038/nrm1837] [Citation(s) in RCA: 1961] [Impact Index Per Article: 108.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Physiologically important cell-signalling networks are complex, and contain several points of regulation, signal divergence and crosstalk with other signalling cascades. Here, we use the concept of 'critical nodes' to define the important junctions in these pathways and illustrate their unique role using insulin signalling as a model system.
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Affiliation(s)
- Cullen M Taniguchi
- Joslin Diabetes Center, One Joslin Place, Boston, Massachusetts 02215, USA
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36
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Ouwens DM, Boer C, Fodor M, de Galan P, Heine RJ, Maassen JA, Diamant M. Cardiac dysfunction induced by high-fat diet is associated with altered myocardial insulin signalling in rats. Diabetologia 2005; 48:1229-37. [PMID: 15864533 DOI: 10.1007/s00125-005-1755-x] [Citation(s) in RCA: 172] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2004] [Accepted: 02/03/2005] [Indexed: 10/25/2022]
Abstract
AIMS/HYPOTHESIS Diabetic cardiomyopathy (DCM) is common in type 2 diabetes. In DCM, insulin resistance may alter cardiac substrate supply and utilisation leading to changes in myocardial metabolism and cardiac function. In rats, exposure to excessive alimentary fat, inducing a type 2 diabetic phenotype, may result in myocardial insulin resistance and cardiac functional changes resembling DCM. MATERIALS AND METHODS Rats received high-fat (HFD) or low-fat (LFD) diets for 7 weeks. Prior to killing, insulin or saline was injected i.p. Contractile function and insulin signalling were assessed in papillary muscles and ventricular lysates, respectively. RESULTS Fasting and post-load blood glucose levels were increased in HFD- vs LFD-rats (all p < 0.02). Mean heart weight, but not body weight, was increased in HFD-rats (p < 0.01). HFD-hearts showed structural changes and triglyceride accumulation. HFD-muscles developed higher baseline and maximum forces, but showed impaired recovery from higher workloads. Insulin-associated modulation of Ca2+-induced force augmentation was abolished in HFD-muscles. HFD reduced insulin-stimulated IRS1-associated phosphatidylinositol 3'-kinase activity and phosphorylation of protein kinase B, glycogen synthase kinase-3beta, endothelial nitric oxide synthase, and forkhead transcription factors by 40-60% (all p < 0.05). Insulin-mediated phosphorylation of phospholamban, a critical regulator of myocardial contractility, was decreased in HFD-hearts (p < 0.05). CONCLUSIONS/INTERPRETATION HFD induced a hypertrophy-like cardiac phenotype, characterised by a higher basal contractile force, an impaired recovery from increased workloads and decreased insulin-mediated protection against Ca2+ overload. Cardiac dysfunction was associated with myocardial insulin resistance and phospholamban hypophosphorylation. Our data suggest that myocardial insulin resistance, resulting from exposure to excessive alimentary fat, may contribute to the pathogenesis of diabetes-related heart disease.
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Affiliation(s)
- D M Ouwens
- Department of Molecular Cell Biology, Leiden University Medical Centre, Wassenaarseweg 72, 2333 AL, Leiden, The Netherlands,
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37
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Yechoor VK, Patti ME, Ueki K, Laustsen PG, Saccone R, Rauniyar R, Kahn CR. Distinct pathways of insulin-regulated versus diabetes-regulated gene expression: an in vivo analysis in MIRKO mice. Proc Natl Acad Sci U S A 2004; 101:16525-30. [PMID: 15546994 PMCID: PMC534529 DOI: 10.1073/pnas.0407574101] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Diabetes mellitus is a complex metabolic disorder accompanied by alterations in cellular physiology, metabolism, and gene expression. These alterations can be primary (due to loss of direct insulin action) or secondary (due to the metabolic perturbations associated with the disease). To dissect and quantitate these two separate effects, we compared the skeletal muscle gene-expression profiles of muscle insulin receptor knockout (MIRKO) mice and their Lox controls in the basal, streptozotocin-induced diabetic, and insulin-treated diabetic states. Pure deficiency of insulin action as present in the MIRKO mouse results in regulation of 130 genes, with down-regulation of NSF (N-ethylmaleimide-sensitive fusion protein) and VAMP-2 (vesicle-associated membrane protein 2), stearoyl CoA desaturase 1, and cAMP-specific phosphodiesterase 4B, as well as up-regulation of some signaling-related genes, such as Akt2, and the fatty-acid transporter CD36. In diabetes, additional transcriptional mechanisms are activated, resulting in alterations in expression of approximately 500 genes, including a highly coordinated down-regulation of genes of the mitochondrial electron-transport chain and one of the mammalian homologues of the histone deacetylase Sir2, which has been implicated in the link between nutrition and longevity. These distinct pathways of direct and indirect regulation of gene expression provide insights into the complex mechanisms of transcriptional control in diabetes and areas of potential therapeutic targeting.
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Affiliation(s)
- Vijay K Yechoor
- Joslin Diabetes Center and Department of Medicine, Harvard Medical School, Boston, MA 02215, USA
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38
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Kulkarni RN, Roper MG, Dahlgren G, Shih DQ, Kauri LM, Peters JL, Stoffel M, Kennedy RT. Islet secretory defect in insulin receptor substrate 1 null mice is linked with reduced calcium signaling and expression of sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA)-2b and -3. Diabetes 2004; 53:1517-25. [PMID: 15161756 DOI: 10.2337/diabetes.53.6.1517] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Mice with deletion of insulin receptor substrate (IRS)-1 (IRS-1 knockout [KO] mice) show mild insulin resistance and defective glucose-stimulated insulin secretion and reduced insulin synthesis. To further define the role of IRS-1 in islet function, we examined the insulin secretory defect in the knockouts using freshly isolated islets and primary beta-cells. IRS-1 KO beta-cells exhibited a significantly shorter increase in intracellular free Ca(2+) concentration ([Ca(2+)](i)) than controls when briefly stimulated with glucose or glyceraldehyde and when l-arginine was used to potentiate the stimulatory effect of glucose. These changes were paralleled by a lower number of exocytotic events in the KO beta-cells in response to the same secretagogues, indicating reduced insulin secretion. Furthermore, the normal oscillations in intracellular Ca(2+) and O(2) consumption after glucose stimulation were dampened in freshly isolated KO islets. Semiquantitative RT-PCR showed a dramatically reduced islet expression of sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA)-2b and -3 in the mutants. These data provide evidence that IRS-1 modulation of insulin secretion is associated with Ca(2+) signaling and expression of SERCA-2b and -3 genes in pancreatic islets and provides a direct link between insulin resistance and defective insulin secretion.
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Affiliation(s)
- Rohit N Kulkarni
- Rm. 602, Joslin Diabetes Center, One Joslin Pl., Boston MA 02215, USA.
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39
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Fasshauer M, Kralisch S, Klier M, Lossner U, Bluher M, Chambaut-Guérin AM, Klein J, Paschke R. Interleukin-6 is a positive regulator of tumor necrosis factor alpha-induced adipose-related protein in 3T3-L1 adipocytes. FEBS Lett 2004; 560:153-7. [PMID: 14988015 DOI: 10.1016/s0014-5793(04)00096-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2003] [Revised: 01/19/2004] [Accepted: 01/22/2004] [Indexed: 02/04/2023]
Abstract
Tumor necrosis factor (TNF) alpha-induced adipose-related protein (TIARP) is a novel TNFalpha-stimulated protein in adipocytes. Besides TNFalpha, interleukin (IL)-6 has recently been shown to be another adipocytokine implicated in insulin resistance. Therefore, the impact of IL-6 on TIARP gene expression in 3T3-L1 adipocytes was determined by quantitative real-time reverse transcription-polymerase chain reaction. Interestingly, TIARP mRNA expression was stimulated up to 3.8-fold by IL-6 in a dose-dependent fashion with significant stimulation detectable at effector concentrations as low as 3 ng/ml and maximal effects seen at 100 ng/ml IL-6. Induction of TIARP mRNA by IL-6 was time-dependent with significant upregulation occurring as early as 2 h after effector addition and maximal effects observed at 4 h. In parallel, TIARP protein synthesis was upregulated with maximal effects seen after 8 h of IL-6 treatment. Furthermore, the Janus kinase 2 inhibitor AG490 decreased TIARP mRNA expression. The increase of TIARP mRNA could be reversed by withdrawal of IL-6 for 24 h. Furthermore, TIARP mRNA induction by IL-6 was also seen in brown adipocytes but not in muscle and liver cells. Taken together, these results show that TIARP is acutely regulated in adipose tissue not only by TNFalpha but also by IL-6 which has been shown to be another important cytokine implicated in the pathogenesis of insulin resistance.
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Affiliation(s)
- Mathias Fasshauer
- University of Leipzig, Department of Internal Medicine III, 04103 Leipzig, Germany
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40
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Okon EB, Szado T, Laher I, McManus B, van Breemen C. Augmented Contractile Response of Vascular Smooth Muscle in a Diabetic Mouse Model. J Vasc Res 2004; 40:520-30. [PMID: 14646372 DOI: 10.1159/000075238] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2003] [Accepted: 08/25/2003] [Indexed: 11/19/2022] Open
Abstract
The vasomotor properties of isolated aortae and mesenteric arteries of insulin-resistant ob/ob and 57CBL/6J mice were compared in organ bath studies. Vessels from ob/ob mice were more sensitive to phenylephrine. Pretreatment with L-NAME caused similar leftward shifts of the phenylephrine concentration response curves in diabetic and non-diabetic vessels. The ob/ob aortae contracted in response to phenylephrine with roughly twice the force while they were not stiffer than control aortae. L-NAME caused a greater percentage increase in maximal force in the control than in the ob/ob tissue. Denudation potentiated force in the control aortae, but not in the ob/ob aortae. Endothelium-dependent relaxation in the ob/ob aortae and mesenteric arteries was impaired as manifested by a decreased sensitivity and maximal relaxation to acetylcholine, while the aortic basal eNOS mRNA levels did not differ between the two strains. In addition, ob/ob aortae were less sensitive to the nitric oxide donor sodium nitroprusside. Inhibition of endogenous prostaglandin synthesis with indomethacin (10 microM) partly normalized the contractile response of the ob/ob aortae and enhanced their endothelium-dependent relaxation. Neither blockade of endothelin-1 receptors (bosentan, 10 microM) nor PKC inhibition (calphostin, 1 microM) affected the contractile response to phenylephrine in the mouse aortae of either strain. In conclusion, vascular dysfunction in the aorta and mesenteric artery of ob/ob mice are due to increased smooth muscle contractility and impaired dilation but not to changes in elasticity of the vascular wall. Endothelium-produced prostaglandins contribute to the increased vasoconstriction.
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MESH Headings
- Animals
- Aorta/cytology
- Aorta/physiology
- Cell Count
- Diabetes Mellitus, Type 2/metabolism
- Diabetes Mellitus, Type 2/physiopathology
- Disease Models, Animal
- Elasticity
- Glucose/metabolism
- Lipid Metabolism
- Mesenteric Arteries/physiology
- Mice
- Mice, Inbred C57BL
- Mice, Obese
- Muscle Contraction/physiology
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/physiology
- Myocytes, Smooth Muscle/cytology
- Myocytes, Smooth Muscle/metabolism
- Nitric Oxide/metabolism
- Nitric Oxide Synthase/genetics
- Nitric Oxide Synthase Type II
- Nitric Oxide Synthase Type III
- Protein Kinase C/metabolism
- Proteoglycans/metabolism
- RNA, Messenger/analysis
- Receptors, Endothelin/metabolism
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Affiliation(s)
- Elena B Okon
- iCAPTUR(4)E Centre and Department of Pathology, University of British Columbia, Vancouver, Canada.
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41
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Borge PD, Wolf BA. Insulin receptor substrate 1 regulation of sarco-endoplasmic reticulum calcium ATPase 3 in insulin-secreting beta-cells. J Biol Chem 2003; 278:11359-68. [PMID: 12524443 DOI: 10.1074/jbc.m209521200] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have previously characterized an insulin receptor substrate 1 (IRS-1)-overexpressing beta-cell line. These beta-cells demonstrated elevated fractional insulin secretion and elevated cytosolic Ca(2+) levels compared with wild-type and vector controls. This effect of IRS-1 may be mediated via an interaction with the sarco-endoplasmic reticulum calcium ATPase (SERCA). Here we demonstrate that IRS-1 and IRS-2 localize to an endoplasmic reticulum (ER)-enriched fraction in beta-cells using subcellular fractionation. We also observe co-localization of both IRS-1 and IRS-2 with ER marker proteins using immunofluorescent confocal microscopy. Furthermore, immuno-electron microscopy studies confirm that IRS-1 and SERCA3b localize to vesicles derived from the ER. In Chinese hamster ovary-T (CHO-T) cells transiently transfected with SERCA3b alone or together with IRS-1, SERCA3b co-immunoprecipitates with IRS-1. This interaction is enhanced with insulin treatment. SERCA3b also co-immunoprecipitates with IRS-1 in wild-type and IRS-1-overexpressing beta-cell lines. Ca(2+) uptake in ER-enriched fractions prepared from wild-type and IRS-1-overexpressing cell lines shows no significant difference, indicating that the previously observed decrease in Ca(2+) uptake by IRS-1-overexpressing cells is not the result of a defect in SERCA. Treatment of wild-type beta-cells with thapsigargin, an inhibitor of SERCA, resulted in an increase in glucose-stimulated fractional insulin secretion similar to that observed in IRS-1-overexpressing cells. The colocalization of IRS proteins and SERCA in the ER of beta-cells increases the likelihood that these proteins can interact with one another. Co-immunoprecipitation of IRS-1 and SERCA in CHO-T cells and beta-cells confirms that these proteins do indeed interact directly. Pharmacological inhibition of SERCA in beta-cells results in enhanced secretion of insulin. Taken together, our data suggest that interaction between IRS proteins and SERCA is an important regulatory step in insulin secretion.
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Affiliation(s)
- Prabhakar D Borge
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia and University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA
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Borge PD, Moibi J, Greene SR, Trucco M, Young RA, Gao Z, Wolf BA. Insulin receptor signaling and sarco/endoplasmic reticulum calcium ATPase in beta-cells. Diabetes 2002; 51 Suppl 3:S427-33. [PMID: 12475786 DOI: 10.2337/diabetes.51.2007.s427] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Glucose is the main physiological secretagogue for insulin secretion by pancreatic beta-cells, and the major biochemical mechanisms involved have been elucidated. In particular, an increase in intracellular calcium is important for insulin exocytosis. More recently, it has become apparent that the beta-cell also has many of the elements of the insulin receptor signal transduction pathway, including the insulin receptor and insulin receptor substrate (IRS) proteins 1 and 2. Studies with transgenic models have shown that the beta-cell-selective insulin receptor knockout and the IRS-1 knockout lead to reduced glucose-induced insulin secretion. Overexpression of the insulin receptor and IRS-1 in beta-cells results in increased insulin secretion and increased cytosolic Ca(2+). We have thus postulated the existence of a novel autocrine-positive feedback loop of insulin on its own secretion involving interaction with the insulin receptor signal transduction pathway and regulation of intracellular calcium homeostasis. Our current working hypothesis is that this glucose-dependent interaction occurs at the level of IRS-1 and the sarco(endo)plasmic reticulum calcium ATPase, the calcium pump of the endoplasmic reticulum.
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Affiliation(s)
- Prabakhar D Borge
- Department of Pathology and Laboratory Medicine, the Children's Hospital of Philadelphia and the University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-4399, USA
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Abstract
Intracellular Ca(2+)-transport ATPases exert a pivotal role in the endoplasmic reticulum and in the compartments of the cellular secretory pathway by maintaining a sufficiently high lumenal Ca(2+) (and Mn(2+)) concentration in these compartments required for an impressive number of vastly different cell functions. At the same time this lumenal Ca(2+) represents a store of releasable activator Ca(2+) controlling an equally impressive number of cytosolic functions. This review mainly focuses on the different Ca(2+)-transport ATPases found in the intracellular compartments of mainly animal non-muscle cells: the sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA) pumps. Although it is not our intention to treat the ATPases of the specialized sarcoplasmic reticulum in depth, we can hardly ignore the SERCA1 pump of fast-twitch skeletal muscle since its structure and function is by far the best understood and it can serve as a guide to understand the other members of the family. In a second part of this review we describe the relatively novel family of secretory pathway Ca(2+)/Mn(2+) ATPases (SPCA), which in eukaryotic cells are primarily found in the Golgi compartment.
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Affiliation(s)
- F Wuytack
- Laboratorium voor Fysiologie, K.U.Leuven, Campus Gasthuisberg, Leuven, Belgium.
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44
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Tseng YH, Ueki K, Kriauciunas KM, Kahn CR. Differential roles of insulin receptor substrates in the anti-apoptotic function of insulin-like growth factor-1 and insulin. J Biol Chem 2002; 277:31601-11. [PMID: 12082100 DOI: 10.1074/jbc.m202932200] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Insulin-like growth factor-1 (IGF-1) and insulin are known to prevent apoptosis. The signaling network of IGF-1 and insulin occurs via multiple pathways involving different insulin receptor substrates (IRSs). To define their roles in the anti-apoptotic function of IGF-1 and insulin, we established brown pre-adipocyte cell lines from wild-type and IRS knockout (KO) animals. In response to 16 h of serum deprivation, IRS-1-deficient cells showed a significant decrease in response to IGF-1 protection from apoptosis, whereas no changes were observed in the IRS-2, IRS-3, or IRS-4 KO cells. Five hours after serum withdrawal, cells already began to undergo apoptosis. At this early time point, IGF-1 and insulin were able to protect both wild-type and IRS-1 KO cells from death by 85-90%. After a longer period of serum deprivation, the protective ability of insulin and IGF-1 was decreased, and this was especially reduced in the IRS-1 KO cells. Reconstitution of these cells with IRS-1, IRS-2, IRS-3, or IRS-1/IRS-2 chimeras restored the anti-apoptotic effects of IGF-1, whereas overexpression of IRS-4 had no effect at long time points and actually reduced the effect of IGF-1 at the short time point. The biochemical basis of the defect in anti-apoptosis was not dependent on phosphorylation of mitogen-activated protein kinase; whereas phosphoinositide 3-kinase activity was decreased by 30% in IRS-1 KO cells. Akt phosphorylation was slightly reduced in these cells. Phosphorylation of the transcription factors cAMP response element-binding protein and FKHR by IGF-1 and insulin was markedly reduced in IRS-1 KO cells. In addition, both IGF-1 and insulin prevented caspase-3 cleavage in the wild-type cells, and this effect was greatly reduced in the IRS-1-deficient cells. These findings suggest that the IRS proteins may play differential roles in the anti-apoptotic effects of IGF-1 and insulin in brown pre-adipocytes, with IRS-1 being predominant, possibly acting through caspase-3-, CREB-, and FKHR-dependent mechanisms.
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Affiliation(s)
- Yu-Hua Tseng
- Research Division, Joslin Diabetes Center, Department of Medicine, Harvard Medical School, Boston, Massachusetts 02215, USA
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45
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Sano H, Liu SCH, Lane WS, Piletz JE, Lienhard GE. Insulin receptor substrate 4 associates with the protein IRAS. J Biol Chem 2002; 277:19439-47. [PMID: 11912194 DOI: 10.1074/jbc.m111838200] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The insulin receptor substrates (IRSs) are key components in signaling from the insulin receptor, and consequently any proteins that interact with them are expected to participate in insulin signaling. In this study we have searched for proteins that interact with IRS-4 by identifying the proteins that coimmunoprecipitated with IRS-4 from human embryonic kidney 293 cells by microsequencing through mass spectrometry. A group of proteins was found. These included phosphatidylinositol 3-kinase, a protein previously identified as an IRS-4 interactor, and several proteins for which there was no previous evidence of IRS-4 association. One of these proteins, named IRAS, that had been found earlier in another context was examined in detail. The results from the overexpression of IRAS, where its amount was about the same as that of IRS-4, indicated that IRAS associated directly with IRS-4 and showed that the increased complexation of IRS-4 with IRAS did not alter the insulin-stimulated tyrosine phosphorylation of IRS-4 or the association of IRS-4 with phosphatidylinositol 3-kinase or Grb2. On the other hand, overexpression of IRAS enhanced IRS-4-dependent insulin stimulation of the extracellularly regulated kinase. The domains of IRAS and IRS-4 responsible for the association of these two proteins were identified, and it was shown that IRAS also associates with IRS-1, IRS-2, and IRS-3.
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Affiliation(s)
- Hiroyuki Sano
- Department of Biochemistry, Dartmouth Medical School, Hanover, New Hampshire 03755, USA
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46
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Romero JR, Rivera A, Monari A, Ceolotto G, Semplicini A, Conlin PR. Increased red cell sodium-lithium countertransport and lymphocyte cytosolic calcium are separate phenotypes in patients with essential hypertension. J Hum Hypertens 2002; 16:353-8. [PMID: 12082497 DOI: 10.1038/sj.jhh.1001387] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2001] [Revised: 11/05/2001] [Accepted: 12/18/2001] [Indexed: 11/09/2022]
Abstract
Increased red blood cell sodium-lithium countertransport (SLC) activity and elevated intracellular calcium have been observed in hypertensive patients. The association of these ion transport abnormalities with each other and with another phenotype, insulin resistance, has been suggested. We investigated whether elevated SLC activity and increased lymphocyte cytosolic calcium (Ca(cyt)) occur in the same individuals and whether either is associated with hyperinsulinaemia. We measured SLC activity, lymphocyte Ca(cyt)and fasting insulin levels in hypertensive patients and normal subjects. Consistent with prior studies, SLC activity was significantly and positively correlated with fasting insulin levels (r = 0.45, P < 0.01). However, SLC activity and lymphocyte Ca(cyt) were significantly but inversely correlated (r = -0.42, P < 0.01) and lymphocyte Ca(cyt) was also inversely correlated with fasting insulin (r = -0.55, P < 0.001). When the study participants were instead separated into two groups based on fasting insulin levels, those above the median (15 microU/ml) had significantly higher SLC activity and significantly lower Ca(cyt). When separated by lymphocyte Ca(cyt) levels (above or below 120 nM) those patients with low lymphocyte Ca(cyt) had significantly higher SLC activity and significantly higher insulin levels. Multiple linear regression showed that fasting insulin was significantly predictive of SLC activity (P = 0.05) and Ca(cyt) (P < 0.01). Thus, elevated SLC activity and increased lymphocyte Ca(cyt) are separate and distinct ion transport phenotypes in hypertensive patients, linked through a relationship to hyperinsulinaemia that is direct with SLC activity and inverse with lymphocyte Ca(cyt).
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Affiliation(s)
- J R Romero
- Endocrinology-Hypertension Division, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
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47
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Roper MG, Qian WJ, Zhang BB, Kulkarni RN, Kahn CR, Kennedy RT. Effect of the insulin mimetic L-783,281 on intracellular Ca2+ and insulin secretion from pancreatic beta-cells. Diabetes 2002; 51 Suppl 1:S43-9. [PMID: 11815457 DOI: 10.2337/diabetes.51.2007.s43] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
L-783,281, an antidiabetic fungal metabolite that has previously been shown to activate insulin signaling in CHO cells, was tested for its effect on intracellular Ca(2+) ([Ca(2+)](i)) and insulin secretion in single mouse pancreatic beta-cells. Application of 10 micromol/l L-783,281 for 40 s to isolated beta-cells in the presence of 3 mmol/l glucose increased [Ca(2+)](i) to 178 +/- 10% of basal levels (n = 18) as measured by fluo-4 fluorescence. L-767,827, an inactive structural analog of the insulin mimetic, had no effect on beta-cell [Ca(2+)](i). The L-783,281-evoked [Ca(2+)](i) increase was reduced by 82 +/- 4% (n = 6, P < 0.001) in cells incubated with 1 micromol/l of the SERCA (sarco/endoplasmic reticulum calcium ATPase) pump inhibitor thapsigargin and reduced by 33 +/- 6% (n = 6, P < 0.05) in cells incubated with 20 micromol/l of the L-type Ca(2+)-channel blocker nifedipine. L-783,281-stimulated [Ca(2+)](i) increases were reduced to 31 +/- 3% (n = 9, P < 0.05) and 48 +/- 10% (n = 6, P < 0.05) of control values by the phosphatidylinositol 3-kinase (PI3-K) inhibitors LY294002 (25 micromol/l) and wortmannin (100 nmol/l), respectively. In beta-cells from IRS-1-/- mice, 10 micromol/l L-783,281 had no significant effect on [Ca(2+)](i) (n = 5). L-783,281 also resulted in insulin secretion at single beta-cells. Application of 10 micromol/l L-783,281 for 40 s resulted in 12.2 +/- 2.1 (n = 14) exocytotic events as measured by amperometry, whereas the inactive structural analog had no stimulatory effect on secretion. Virtually no secretion was evoked by L-783,281 in IRS-1-/- beta-cells. LY294002 (25 micromol/l) significantly reduced the effect of the insulin mimetic on beta-cell exocytosis. It is concluded that L-783,281 evokes [Ca(2+)](i) increases and exocytosis in beta-cells via an IRS-1/PI3-K-dependent pathway and that the [Ca(2+)](i) increase involves release of Ca(2+) from intracellular stores.
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Affiliation(s)
- Michael G Roper
- Department of Chemistry, University of Florida, Gainesville, FL, USA
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Emkey R, Kahn CR. Molecular Aspects of Insulin Signaling. Compr Physiol 2001. [DOI: 10.1002/cphy.cp070212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Korvald C, Elvenes OP, Myrmel T, Sørlie DG. Cardiac dysfunction and inefficiency after substrate-enriched warm blood cardioplegia. Eur J Cardiothorac Surg 2001; 20:555-62; discussion 562-4. [PMID: 11509279 DOI: 10.1016/s1010-7940(01)00849-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE The study assessed the outcome after prolonged warm continuous antegrade blood cardioplegia (WCBC) with substrate enrichment, in terms of mechanical performance and mechanoenergetic efficiency. METHODS WCBC was given for 3 h to three groups of pigs on cardiopulmonary bypass; WCBC alone (n=7), WCBC+glucose and insulin (+GIK, n=7) and WCBC+L-glutamine (+GLN, n=7). Cardiac systolic and diastolic function, pressure-volume area (PVA) and myocardial oxygen consumption (MVO(2)) were assessed before, and twice after WCBC using pressure-conductance catheter, coronary flow-probes and O(2)-content difference. RESULTS In the WCBC, +GIK and +GLN groups respectively, the following parameters decreased after WCBC compared to baseline: left ventricular developed pressure by 26, 19 and 25% (P<0.001); dP/dt(max) by 36, 37 and 34% (P<0.001); preload recruitable stroke work by 35, 41 and 28% (P<0.001); mechanoenergetic efficiency (PVA/MVO(2)) by 44, 41 and 22% (P<0.001). End-diastolic stiffness increased early after WCBC in the WCBC and +GLN groups, while it was unchanged in the +GIK group (P=0.032). CONCLUSION Despite continuous aerobic conditions and additional substrates, post-WCBC cardiac contractile function and mechanoenergetic efficiency was severely depressed. The results demonstrate the hazards of sustained normothermic hyperkalemic perfusion.
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Affiliation(s)
- C Korvald
- Department of Thoracic and Cardiovascular Surgery, University Hospital in Tromsø, Tromsø, Norway.
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Abstract
Rapid progress has been made recently in the definition of growth hormone (GH) receptor signal transduction pathways. It is now apparent that many cytokines, including GH, share identical or similar signalling components to exert their cellular effects. This review provides a brief discourse on the signal transduction pathways, which have been demonstrated to be utilized by GH. The identification of such pathways provides a basis for understanding the pleiotropic actions of GH. The mechanisms by which the specific cellular effects of GH are achieved remain to be elucidated.
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Affiliation(s)
- T Zhu
- Institute of Molecular and Cell Biology, 30 Medical Drive, Singapore 117609, Singapore
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