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Landa-Galvan HV, Rios-Castro E, Romero-Garcia T, Rueda A, Olivares-Reyes JA. Metabolic syndrome diminishes insulin-induced Akt activation and causes a redistribution of Akt-interacting proteins in cardiomyocytes. PLoS One 2020; 15:e0228115. [PMID: 31995605 PMCID: PMC6988918 DOI: 10.1371/journal.pone.0228115] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 01/07/2020] [Indexed: 12/31/2022] Open
Abstract
Metabolic syndrome (MetS) is a cluster of cardiometabolic risk factors, with insulin resistance as a critical component for its development. Insulin signaling in the heart leads to Akt (also known as PKB) activation, a serine/threonine protein kinase, which regulates cardiac glucose metabolism and growth. Cardiac metabolic inflexibility, characterized by impaired insulin-induced glucose uptake and oxidation, has been reported as an early and consistent change in the heart of different models of MetS and diabetes; however, the evaluation of Akt activation has yielded variable results. Here we report in cardiomyocytes of MetS rats, diminished insulin-induced glucose uptake and Akt activation, evaluated by its impaired mobilization towards the plasma membrane and phosphorylation, and reflected in a re-distribution of its interacting proteins, assessed by label-free mass spectrometry (data are available via ProteomeXchange with identifier PXD013260). We report 45 proteins with diminished abundance in Akt complex of MetS cardiomyocytes, mainly represented by energy metabolism-related proteins, and also, 31 Akt-interacting proteins with increased abundance, which were mainly related to contraction, endoplasmic reticulum stress, and Akt negative regulation. These results emphasize the relevance of Akt in the regulation of energy metabolism in the heart and highlight Akt-interacting proteins that could be involved in the detrimental effects of MetS in the heart.
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Affiliation(s)
| | - Emmanuel Rios-Castro
- Unidad de Genomica, Proteomica y Metabolomica (UGPM), LaNSE-Cinvestav-IPN, Mexico City, Mexico
| | | | - Angelica Rueda
- Departamento de Bioquimica, Cinvestav-IPN, Mexico City, Mexico
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2
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Zafirovic S, Obradovic M, Sudar-Milovanovic E, Jovanovic A, Stanimirovic J, Stewart AJ, Pitt SJ, Isenovic ER. 17β-Estradiol protects against the effects of a high fat diet on cardiac glucose, lipid and nitric oxide metabolism in rats. Mol Cell Endocrinol 2017; 446:12-20. [PMID: 28163099 DOI: 10.1016/j.mce.2017.02.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 01/17/2017] [Accepted: 02/01/2017] [Indexed: 12/26/2022]
Abstract
The aim of this study was to investigate the in vivo effects of 17β-estradiol (E2) on myocardial metabolism and inducible nitric oxide synthase (iNOS) expression/activity in obese rats. Male Wistar rats were fed with a normal or a high fat (HF) diet (42% fat) for 10 weeks. Half of the HF fed rats were treated with a single dose of E2 while the other half were placebo-treated. 24 h after treatment animals were sacrificed. E2 reduced cardiac free fatty acid (FFA) (p < 0.05), L-arginine (p < 0.01), iNOS mRNA (p < 0.01), and protein (p < 0.05) levels and translocation of the FFA transporter (CD36) (p < 0.01) to the plasma membrane (PM) in HF fed rats. In contrast, Akt phosphorylation at Thr308 (p < 0.05) and translocation of the glucose transporter GLUT4 (p < 0.05) to the PM increased after E2 treatment in HF rats. Our results indicate that E2 acts via the PI3K/Akt signalling pathway to partially protect myocardial metabolism by attenuating the detrimental effects of increased iNOS expression/activity in HF fed rats.
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Affiliation(s)
- Sonja Zafirovic
- Institute of Nuclear Sciences Vinca, University of Belgrade, Laboratory of Radiobiology and Molecular Genetics, Mike Petrovica Alasa 12-14, 11000 Belgrade, Serbia.
| | - Milan Obradovic
- Institute of Nuclear Sciences Vinca, University of Belgrade, Laboratory of Radiobiology and Molecular Genetics, Mike Petrovica Alasa 12-14, 11000 Belgrade, Serbia.
| | - Emina Sudar-Milovanovic
- Institute of Nuclear Sciences Vinca, University of Belgrade, Laboratory of Radiobiology and Molecular Genetics, Mike Petrovica Alasa 12-14, 11000 Belgrade, Serbia.
| | - Aleksandra Jovanovic
- Institute of Nuclear Sciences Vinca, University of Belgrade, Laboratory of Radiobiology and Molecular Genetics, Mike Petrovica Alasa 12-14, 11000 Belgrade, Serbia.
| | - Julijana Stanimirovic
- Institute of Nuclear Sciences Vinca, University of Belgrade, Laboratory of Radiobiology and Molecular Genetics, Mike Petrovica Alasa 12-14, 11000 Belgrade, Serbia.
| | - Alan J Stewart
- School of Medicine, University of St Andrews, North Haugh, St Andrews, KY16 9TF, United Kingdom.
| | - Samantha J Pitt
- School of Medicine, University of St Andrews, North Haugh, St Andrews, KY16 9TF, United Kingdom.
| | - Esma R Isenovic
- Institute of Nuclear Sciences Vinca, University of Belgrade, Laboratory of Radiobiology and Molecular Genetics, Mike Petrovica Alasa 12-14, 11000 Belgrade, Serbia.
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Yilmaz S, Canpolat U, Aydogdu S, Abboud HE. Diabetic Cardiomyopathy; Summary of 41 Years. Korean Circ J 2015; 45:266-72. [PMID: 26240579 PMCID: PMC4521103 DOI: 10.4070/kcj.2015.45.4.266] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Revised: 01/27/2015] [Accepted: 03/05/2015] [Indexed: 01/04/2023] Open
Abstract
Patients with diabetes have an increased risk for development of cardiomyopathy, even in the absence of well known risk factors like coronary artery disease and hypertension. Diabetic cardiomyopathy was first recognized approximately four decades ago. To date, several pathophysiological mechanisms thought to be responsible for this new entity have also been recognized. In the presence of hyperglycemia, non-enzymatic glycosylation of several proteins, reactive oxygen species formation, and fibrosis lead to impairment of cardiac contractile functions. Impaired calcium handling, increased fatty acid oxidation, and increased neurohormonal activation also contribute to this process. Demonstration of left ventricular hypertrophy, early diastolic and late systolic dysfunction by sensitive techniques, help us to diagnose diabetic cardiomyopathy. Traditional treatment of heart failure is beneficial in diabetic cardiomyopathy, but specific strategies for prevention or treatment of cardiac dysfunction in diabetic patients has not been clarified yet. In this review we will discuss clinical and experimental studies focused on pathophysiology of diabetic cardiomyopathy, and summarize diagnostic and therapeutic approaches developed towards this entity.
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Affiliation(s)
- Samet Yilmaz
- Turkey Yuksek Ihtisas Education and Research Hospital, Cardiology Clinic, Ankara, Turkey
| | - Ugur Canpolat
- Turkey Yuksek Ihtisas Education and Research Hospital, Cardiology Clinic, Ankara, Turkey
| | - Sinan Aydogdu
- Turkey Yuksek Ihtisas Education and Research Hospital, Cardiology Clinic, Ankara, Turkey
| | - Hanna Emily Abboud
- Division of Nephrology, University of Texas Health Science Center, San Antonio, TX, USA
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Sárközy M, Szűcs G, Pipicz M, Zvara Á, Éder K, Fekete V, Szűcs C, Bárkányi J, Csonka C, Puskás LG, Kónya C, Ferdinandy P, Csont T. The effect of a preparation of minerals, vitamins and trace elements on the cardiac gene expression pattern in male diabetic rats. Cardiovasc Diabetol 2015; 14:85. [PMID: 26126619 PMCID: PMC4499218 DOI: 10.1186/s12933-015-0248-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 06/17/2015] [Indexed: 02/06/2023] Open
Abstract
Background Diabetic patients have an increased risk of developing cardiovascular diseases, which are the leading cause of death in developed countries. Although multivitamin products are widely used as dietary supplements, the effects of these products have not been investigated in the diabetic heart yet. Therefore, here we investigated if a preparation of different minerals, vitamins, and trace elements (MVT) affects the cardiac gene expression pattern in experimental diabetes. Methods Two-day old male Wistar rats were injected with streptozotocin (i.p. 100 mg/kg) or citrate buffer to induce diabetes. From weeks 4 to 12, rats were fed with a vehicle or a MVT preparation. Fasting blood glucose measurement and oral glucose tolerance test were performed at week 12, and then total RNA was isolated from the myocardium and assayed by rat oligonucleotide microarray for 41012 oligonucleotides. Results Significantly elevated fasting blood glucose concentration and impaired glucose tolerance were markedly improved by MVT-treatment in diabetic rats at week 12. Genes with significantly altered expression due to diabetes include functional clusters related to cardiac hypertrophy (e.g. caspase recruitment domain family, member 9; cytochrome P450, family 26, subfamily B, polypeptide; FXYD domain containing ion transport regulator 3), stress response (e.g. metallothionein 1a; metallothionein 2a; interleukin-6 receptor; heme oxygenase (decycling) 1; and glutathione S-transferase, theta 3), and hormones associated with insulin resistance (e.g. resistin; FK506 binding protein 5; galanin/GMAP prepropeptide). Moreover the expression of some other genes with no definite cardiac function was also changed such as e.g. similar to apolipoprotein L2; brain expressed X-linked 1; prostaglandin b2 synthase (brain). MVT-treatment in diabetic rats showed opposite gene expression changes in the cases of 19 genes associated with diabetic cardiomyopathy. In healthy hearts, MVT-treatment resulted in cardiac gene expression changes mostly related to immune response (e.g. complement factor B; complement component 4a; interferon regulatory factor 7; hepcidin). Conclusions MVT-treatment improved diagnostic markers of diabetes. This is the first demonstration that MVT-treatment significantly alters cardiac gene expression profile in both control and diabetic rats. Our results and further studies exploring the mechanistic role of individual genes may contribute to the prevention or diagnosis of cardiac complications in diabetes. Electronic supplementary material The online version of this article (doi:10.1186/s12933-015-0248-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Márta Sárközy
- Department of Biochemistry, Faculty of Medicine, University of Szeged, Szeged, Hungary.
| | - Gergő Szűcs
- Department of Biochemistry, Faculty of Medicine, University of Szeged, Szeged, Hungary.
| | - Márton Pipicz
- Department of Biochemistry, Faculty of Medicine, University of Szeged, Szeged, Hungary.
| | - Ágnes Zvara
- Institute of Genetics, Biological Research Center of the Hungarian Academy of Sciences, Szeged, Hungary.
| | - Katalin Éder
- Department of Genetics, Cell- and Immunobiology, Semmelweis University, Budapest, Hungary.
| | - Veronika Fekete
- Department of Biochemistry, Faculty of Medicine, University of Szeged, Szeged, Hungary.
| | | | | | - Csaba Csonka
- Department of Biochemistry, Faculty of Medicine, University of Szeged, Szeged, Hungary.
| | - László G Puskás
- Institute of Genetics, Biological Research Center of the Hungarian Academy of Sciences, Szeged, Hungary.
| | - Csaba Kónya
- Béres Pharmaceuticals Ltd, Budapest, Hungary.
| | - Péter Ferdinandy
- Pharmahungary Group, Szeged, Hungary. .,Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary.
| | - Tamás Csont
- Department of Biochemistry, Faculty of Medicine, University of Szeged, Szeged, Hungary.
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Rashid K, Sil PC. Curcumin enhances recovery of pancreatic islets from cellular stress induced inflammation and apoptosis in diabetic rats. Toxicol Appl Pharmacol 2015; 282:297-310. [PMID: 25541178 DOI: 10.1016/j.taap.2014.12.003] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 12/08/2014] [Accepted: 12/12/2014] [Indexed: 12/30/2022]
Abstract
The phytochemical, curcumin, has been reported to play many beneficial roles. However, under diabetic conditions, the detail mechanism of its beneficial action in the glucose homeostasis regulatory organ, pancreas, is poorly understood. The present study has been designed and carried out to explore the role of curcumin in the pancreatic tissue of STZ induced and cellular stress mediated diabetes in eight weeks old male Wistar rats. Diabetes was induced with a single intraperitoneal dose of STZ (65 mg/kg body weight). Post to diabetes induction, animals were treated with curcumin at a dose of 100 mg/kg body weight for eight weeks. Underlying molecular and cellular mechanism was determined using various biochemical assays, DNA fragmentation, FACS, histology, immunoblotting and ELISA. Treatment with curcumin reduced blood glucose level, increased plasma insulin and mitigated oxidative stress related markers. In vivo and in vitro experimental results revealed increased levels of proinflammatory cytokines (TNF-α, IL1-β and IFN-γ), reduced level of cellular defense proteins (Nrf-2 and HO-1) and glucose transporter (GLUT-2) along with enhanced levels of signaling molecules of ER stress dependent and independent apoptosis (cleaved Caspase-12/9/8/3) in STZ administered group. Treatment with curcumin ameliorated all the adverse changes and helps the organ back to its normal physiology. Results suggest that curcumin protects pancreatic beta-cells by attenuating inflammatory responses, and inhibiting ER/mitochondrial dependent and independent pathways of apoptosis and crosstalk between them. This uniqueness and absence of any detectable adverse effect proposes the possibility of using this molecule as an effective protector in the cellular stress mediated diabetes mellitus.
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Affiliation(s)
- Kahkashan Rashid
- Division of Molecular Medicine, Bose Institute, P-1/12, CIT Scheme VII M, Kolkata 700054, India
| | - Parames C Sil
- Division of Molecular Medicine, Bose Institute, P-1/12, CIT Scheme VII M, Kolkata 700054, India.
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Montessuit C, Lerch R. Regulation and dysregulation of glucose transport in cardiomyocytes. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2012; 1833:848-56. [PMID: 22967513 DOI: 10.1016/j.bbamcr.2012.08.009] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Revised: 08/08/2012] [Accepted: 08/10/2012] [Indexed: 11/29/2022]
Abstract
The ability of the heart muscle to derive energy from a wide variety of substrates provides the myocardium with remarkable capacity to adapt to the ever-changing metabolic environment depending on factors including nutritional state and physical activity. There is increasing evidence that loss of metabolic flexibility of the myocardium contributes to cardiac dysfunction in disease conditions such as diabetes, ischemic heart disease and heart failure. At the level of glucose metabolism reduced metabolic adaptation in most cases is characterized by impaired stimulation of transarcolemmal glucose transport in the cardiomyocytes in response to insulin, referred to as insulin resistance, or to other stimuli such as energy deficiency. This review discusses cellular mechanisms involved in the regulation of glucose uptake in cardiomyocytes and their potential implication in impairment of stimulation of glucose transport under disease conditions. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Cardiac Pathways of Differentiation, Metabolism and Contraction.
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Affiliation(s)
- Christophe Montessuit
- Department of Medical Specialties, Geneva University Hospitals, Geneva, Switzerland.
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7
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Taurine exerts hypoglycemic effect in alloxan-induced diabetic rats, improves insulin-mediated glucose transport signaling pathway in heart and ameliorates cardiac oxidative stress and apoptosis. Toxicol Appl Pharmacol 2011; 258:296-308. [PMID: 22138235 DOI: 10.1016/j.taap.2011.11.009] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2011] [Revised: 11/03/2011] [Accepted: 11/15/2011] [Indexed: 12/15/2022]
Abstract
Hyperlipidemia, inflammation and altered antioxidant profiles are the usual complications in diabetes mellitus. In the present study, we investigated the therapeutic potential of taurine in diabetes associated cardiac complications using a rat model. Rats were made diabetic by alloxan (ALX) (single i.p. dose of 120mg/kg body weight) and left untreated or treated with taurine (1% w/v, orally, in water) for three weeks either from the day of ALX exposure or after the onset of diabetes. Animals were euthanized after three weeks. ALX-induced diabetes decreased body weight, increased glucose level, decreased insulin content, enhanced the levels of cardiac damage markers and altered lipid profile in the plasma. Moreover, it increased oxidative stress (decreased antioxidant enzyme activities and GSH/GSSG ratio, increased xanthine oxidase enzyme activity, lipid peroxidation, protein carbonylation and ROS generation) and enhanced the proinflammatory cytokines levels, activity of myeloperoxidase and nuclear translocation of NFκB in the cardiac tissue of the experimental animals. Taurine treatment could, however, result to a decrease in the elevated blood glucose and proinflammatory cytokine levels, diabetes-evoked oxidative stress, lipid profiles and NFκB translocation. In addition, taurine increased GLUT 4 translocation to the cardiac membrane by enhanced phosphorylation of IR and IRS1 at tyrosine and Akt at serine residue in the heart. Results also suggest that taurine could protect cardiac tissue from ALX induced apoptosis via the regulation of Bcl2 family and caspase 9/3 proteins. Taken together, taurine supplementation in regular diet could play a beneficial role in regulating diabetes and its associated complications in the heart.
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Tarquini R, Lazzeri C, Pala L, Rotella CM, Gensini GF. The diabetic cardiomyopathy. Acta Diabetol 2011; 48:173-81. [PMID: 20198391 DOI: 10.1007/s00592-010-0180-x] [Citation(s) in RCA: 108] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2009] [Accepted: 02/11/2010] [Indexed: 12/11/2022]
Abstract
Diabetic cardiomyopathy has been defined as "a distinct entity characterized by the presence of abnormal myocardial performance or structure in the absence of epicardial coronary artery disease, hypertension, and significant valvular disease". The diagnosis stems from the detection of myocardial abnormalities and the exclusion of other contributory causes of cardiomyopathy. It rests on non-invasive imaging techniques which can demonstrate myocardial dysfunction across the spectra of clinical presentation. The presence of diabetes is associated with an increased risk of developing heart failure, and the 75% of patients with unexplained idiopathic dilated cardiomyopathy were found to be diabetic. Diabetic patients with microvascular complications show the strongest association between diabetes and cardiomyopathy, an association that parallels the duration and severity of hyperglycemia. Metabolic abnormalities (that is hyperglycemia, hyperinsulinemia, and hyperlipemia) can lead to the cellular alterations characterizing diabetic cardiomyopathy (that is myocardial fibrosis and/or myocardial hypertrophy) directly or indirectly (that is by means of renin-angiotensin system activation, cardiac autonomic neuropathy, alterations in calcium homeostasis). Moreover, metabolic abnormalities represent, on a clinical ground, the main therapeutic target in the patients with diabetes since the diagnosis of diabetes is made. Since diabetic cardiomyopathy is highly prevalent in the asymptomatic type 2 diabetic patients, screening for its presence at the earliest stage of development can lead to prevent the progression to chronic heart failure. The most sensitive test is standard echocardiogram, while a less expensive pre-screening method is the detection of microalbuminuria.
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Affiliation(s)
- Roberto Tarquini
- Department of Internal Medicine, Azienda Ospedaliero-Universitaria Careggi, University of Florence, Italy.
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9
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Sussman MA, Völkers M, Fischer K, Bailey B, Cottage CT, Din S, Gude N, Avitabile D, Alvarez R, Sundararaman B, Quijada P, Mason M, Konstandin MH, Malhowski A, Cheng Z, Khan M, McGregor M. Myocardial AKT: the omnipresent nexus. Physiol Rev 2011; 91:1023-70. [PMID: 21742795 PMCID: PMC3674828 DOI: 10.1152/physrev.00024.2010] [Citation(s) in RCA: 180] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
One of the greatest examples of integrated signal transduction is revealed by examination of effects mediated by AKT kinase in myocardial biology. Positioned at the intersection of multiple afferent and efferent signals, AKT exemplifies a molecular sensing node that coordinates dynamic responses of the cell in literally every aspect of biological responses. The balanced and nuanced nature of homeostatic signaling is particularly essential within the myocardial context, where regulation of survival, energy production, contractility, and response to pathological stress all flow through the nexus of AKT activation or repression. Equally important, the loss of regulated AKT activity is primarily the cause or consequence of pathological conditions leading to remodeling of the heart and eventual decompensation. This review presents an overview compendium of the complex world of myocardial AKT biology gleaned from more than a decade of research. Summarization of the widespread influence that AKT exerts upon myocardial responses leaves no doubt that the participation of AKT in molecular signaling will need to be reckoned with as a seemingly omnipresent regulator of myocardial molecular biological responses.
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Affiliation(s)
- Mark A Sussman
- Department of Biology, San Diego State University, SDSU Heart Institute, San Diego, California 92182, USA.
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10
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PET detection of the impact of dobutamine on myocardial glucose metabolism in women with type 1 diabetes mellitus. J Nucl Cardiol 2009; 15:791-9. [PMID: 18984454 DOI: 10.1007/bf03007360] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND Our objective was to determine, in the hearts of women with type 1 diabetes mellitus (T1DM), whether the fate of extracted glucose is altered and, if so, what the impact of dobutamine is on myocardial substrate metabolism. In experimental models of T1DM, myocardial glycolysis and glucose oxidation are reduced with the impairment becoming more pronounced with dobutamine. Whether similar changes occur in humans with T1DM is unclear. METHODS AND RESULTS Myocardial perfusion, oxygen consumption, and glucose and fatty acid metabolism were measured with positron emission tomography in 19 women, 7 normal volunteers (NVs) and 12 with T1DM. The NVs and 6 T1DM (DM1) patients were studied under baseline metabolic conditions and 6 T1DM patients were studied during hyperinsulinemic-euglycemic clamp (DM1-C), both at rest and during dobutamine. At rest, myocardial glucose uptake, glycolysis, glycogen storage, and oxidation were reduced by similar levels in DM1 patients compared with NVs (P < .05). During dobutamine, although myocardial glucose uptake was not different from DM1 patients at rest, fractional glycolysis was lower compared with NVs or DM1-C patients and reflected a lower glucose oxidation rate (P < .001). Measurements of myocardial glucose metabolism at rest and during dobutamine were comparable between NVs and DM1-C patients. During dobutamine, myocardial fatty acid uptake and oxidation increased in all 3 groups. CONCLUSIONS In women with T1DM, (1) myocardial glucose metabolism is impaired downstream from initial uptake, (2) these abnormalities become more pronounced with dobutamine and are paralleled by an increase in myocardial fatty acid metabolism, and (3) insulin restores glucose metabolism to levels observed in normal control subjects.
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Wei D, Li M, Ding W. Effect of vanadate on gene expression of the insulin signaling pathway in skeletal muscle of streptozotocin-induced diabetic rats. J Biol Inorg Chem 2007; 12:1265-73. [PMID: 17874149 DOI: 10.1007/s00775-007-0294-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2007] [Accepted: 08/20/2007] [Indexed: 11/30/2022]
Abstract
An insulin signaling pathway microarray was used to evaluate the gene expression profiling of the insulin signaling pathway in the skeletal muscle of streptozotocin-induced diabetic, NaVO(3)-treated diabetic and insulin-treated diabetic rats for the investigation of the effect of vanadium and insulin on the insulin signaling pathway. Of 96 genes surveyed, transcriptional patterns of 19 genes (20%) showed alterations in diabetic rats compared with controls. Although most of these changed gene expressions were improved after treatment with NaVO(3) (14, 74%) and insulin (16, 84%), NaVO(3) and insulin treatment resulted in the alteration of 20 and 12 additional gene transcripts compared no treatment. We found that both NaVO(3) and insulin treatment achieved a desirable glucose level and most of the alterative gene transcripts in diabetic rats were normalized with NaVO(3) and insulin treatment. Comparison of the gene expression profiling indicates that there is a significant difference between the NaVO(3)-treated group and the insulin-treated group. The present study demonstrated for the first time that several candidate genes of the insulin signaling pathway are involved in the effect of vanadium treatment on hyperglycemia. This study opens the way for more focused investigations that may identify the genes responsible for diabetes and vanadium treatment in the global insulin signaling pathway.
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Affiliation(s)
- Dan Wei
- Department of Biology, Graduate University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing, People's Republic of China
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12
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Clerk A, Cullingford TE, Fuller SJ, Giraldo A, Markou T, Pikkarainen S, Sugden PH. Signaling pathways mediating cardiac myocyte gene expression in physiological and stress responses. J Cell Physiol 2007; 212:311-22. [PMID: 17450511 DOI: 10.1002/jcp.21094] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The contractile cells in the heart (the cardiac myocytes) are terminally differentiated. In response to pathophysiological stresses, cardiac myocytes undergo hypertrophic growth or apoptosis, responses associated with the development of cardiac pathologies. There has been much effort expended in gaining an understanding of the stimuli which promote these responses, and in identifying the intracellular signaling pathways which are activated and potentially involved. These signaling pathways presumably modulate gene and protein expression to elicit the end-stage response. For the regulation of gene expression, the signal may traverse the cytoplasm to modulate nuclear-localized transcription factors as occurs with the mitogen-activated protein kinase or protein kinase B/Akt cascades. Alternatively, the signal may promote translocation of transcription factors from the cytoplasm to the nucleus as is seen with the calcineurin/NFAT and JAK/STAT systems. We present an overview of the principal signaling pathways implicated in the regulation of gene expression in cardiac myocyte pathophysiology, and summarize the current understanding of these pathways, the transcription factors they regulate and the changes in gene expression associated with the development of cardiac pathologies. Finally, we discuss how intracellular signaling and gene expression may be integrated to elicit the overall change in cellular phenotype.
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Affiliation(s)
- Angela Clerk
- NHLI Division, Faculty of Medicine, Imperial College London, London, UK.
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13
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Abstract
Although diabetes is recognized as a potent and prevalent risk factor for ischemic heart disease, less is known as to whether diabetes causes an altered cardiac phenotype independent of coronary atherosclerosis. Left ventricular systolic and diastolic dysfunction, left ventricular hypertrophy, and alterations in the coronary microcirculation have all been observed, although not consistently, in diabetic cardiomyopathy and are not fully explained by the cellular effects of hyperglycemia alone. The recent recognition that diabetes involves more than abnormal glucose homeostasis provides important new opportunities to examine and understand the impact of complex metabolic disturbances on cardiac structure and function.
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Affiliation(s)
- Indu G Poornima
- Department of Medicine, Allegheny General Hospital, Pittsburgh, PA 15212, USA
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14
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Zhao R, Li Q, Xiao B. Effect of Lycium barbarum polysaccharide on the improvement of insulin resistance in NIDDM rats. YAKUGAKU ZASSHI 2005; 125:981-8. [PMID: 16327243 DOI: 10.1248/yakushi.125.981] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Lycium barbarum is one of the traditional oriental medicines. It has been reported to reduce blood glucose levels. In this study, the effect of Lycium barbarum polysaccharide (LBP) on the improvement of insulin resistance and lipid profile was studied in rats, a model for non-insulin dependent diabetes mellitus (NIDDM). The rats were divided into three groups: control, NIDDM control, and NIDDM+LBP. Diabetes model groups were made by feeding high-fat diet and subjecting to i.p. streptozotocin (50 mg/kg). LBP treatment for 3 weeks resulted in a significant decrease in the concentration of plasma triglyceride and weight in NIDDM rats. Furthermore, LBP markedly decreased the plasma cholesterol levels and fasting plasma insulin levels, and the postprandial glucose level at 30 min during oral glucose tolerance test and significantly increased the Insulin Sensitive Index in NIDDM rats. In the present study, we have tested that LBP can alleviate insulin resistance and the effect of LBP is associated with increasing cell-surface level of glucose transporter 4 (GLUT4) in skeletal muscle of NIDDM rats. Under insulin stimulus, GLUT4 content in plasma membrane in NIDDM control rats was significantly lower than that of control (p<0.01), and GLUT4 content in the plasma membrane in NIDDM+LBP rats was higher than that of NIDDM control rats (p<0.01). In conclusion, LBP can ameliorate insulin resistance, and the mechanism may be involved in increasing cell-surface level of GLUT4, improving GLUT4 trafficking and intracellular insulin signaling.
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Affiliation(s)
- Rui Zhao
- Department of Biological Engineering, College of Environment & Chemical Engineering, Yanshan University, No. 438 Hebei Street, Qinhuangdao 066004, P.R. China
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Abstract
There is compelling evidence that alterations in myocardial substrate use play a key role in a variety of normal and abnormal cardiac conditions such as aging, left ventricular hypertrophy, and diabetic heart disease. However, it is unclear whether the metabolic changes are adaptive or maladaptive. Development of transgenic models targeting key aspects of myocardial substrate use, such as uptake, oxidation, and storage, is accelerating our understanding of the metabolic perturbations of cardiac disease. However, whether the metabolic phenotype in these models is relevant to the human condition is frequently unknown. The importance of altered myocardial metabolism in the pathogenesis of cardiac disease is underscored by the current robust development of novel therapeutics that target myocardial substrate use. Currently, magnetic resonance spectroscopy, single photon emission computed tomography, and positron emission tomography are the 3 methods available to image myocardial substrate metabolism. In this review the role of metabolic imaging in the study of specific cardiac disease processes will be discussed. Both the current and future capabilities of metabolic imaging to furthering our understanding of cardiac disease are highlighted.
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Affiliation(s)
- Pilar Herrero
- Division of Radiological Sciences, Mallinckrodt Institute of Radiology, St Louis, MO 63110, USA
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Toblli JE, Cao G, DeRosa G, Forcada P. Reduced cardiac expression of plasminogen activator inhibitor 1 and transforming growth factor beta1 in obese Zucker rats by perindopril. Heart 2005; 91:80-6. [PMID: 15604340 PMCID: PMC1768649 DOI: 10.1136/hrt.2003.022707] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
OBJECTIVE To determine whether angiotensin converting enzyme inhibition by perindopril can reduce cardiac transforming growth factor beta1 (TGFbeta1) and plasminogen activator inhibitor 1 (PAI-1) and therefore control collagen accumulation in an animal model with the metabolic syndrome such as the obese Zucker rat (OZR). ANIMALS Male OZR (group 1, n = 10); OZR treated with perindopril (group 2, n = 10); and lean Zucker rats (group 3, n = 10). METHODS During six months, group 2 received 3 mg/kg/day of perindopril orally and group 1 and group 3 were given a vehicle. Hearts were processed for pathology studies including immunohistochemical analysis with antibodies to PAI-1, TGFbeta1, collagen type I, and collagen type III. RESULTS Group 2 had lower blood pressure (126.7 (2) v 148.6 (2.7) mm Hg, p < 0.01) than untreated OZR and had decreased cardiac PAI-1 (3.6 (0.4) v 13.5 (1.7)% of positive area/field, p < 0.01), TGFbeta1 in myocytes (0.13 (0.1) v 9.14 (4.7)%/area, p < 0.01) and in interstitium (19.8 (6.8) v 178.9 (27.4) positive cells/area, p < 0.01), collagen I (3 (0.8) v 13.3 (1)%/area, p < 0.01), collagen III (5 (0.6) v 9.5 (0.9)%/area, p < 0.01), and collagen I to collagen III ratio (0.59 (0.13) v 1.40 (0.15) p < 0.01) compared with untreated OZR. CONCLUSION These results suggest that perindopril reduces cardiac PAI-1 and TGFbeta1 and ameliorates cardiac fibrosis in a rat model with multiple cardiovascular risk factors.
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Affiliation(s)
- J E Toblli
- Laboratory of Experimental Medicine, Hospital Alemán, CONICET, Av Pueyrredon 1640, Buenos Aires 1118, Argentina.
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Toblli JE, DeRosa G, Cao G, Piorno P, Pagano P. ACE inhibitor and angiotensin type I receptor antagonist in combination reduce renal damage in obese Zucker rats. Kidney Int 2004; 65:2343-59. [PMID: 15149348 DOI: 10.1111/j.1523-1755.2004.00661.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND In this study, we evaluated whether a combination of an angiotensin-converting enzyme (ACE) inhibitor, benazepril (B), with an angiotensin type I receptor antagonist (AT1RA), irbesartan (I), is as effective or more than drugs as monotherapy in controlling renal damage in obese Zucker rats (OZR), a model of metabolic syndrome. METHODS During six months, G1 (OZR receiving no treatment); G2 (OZR with B 10 mg/kg/day); G3 (OZR with I 50mg/kg/day); and G4 (OZR with B 5mg/kg/day + I 25 mg/kg/day). Kidneys were processed for light microscopy (LM) and immunohistochemistry, including antibodies against interstitial alpha-smooth-muscle-actin (alpha-SMA), plasminogen activator inhibitor-1 (PAI-1), transforming growth factor-beta(1)(TGF-beta 1), and collagen (COL) I, III, and IV. RESULTS All treated groups presented similar reduction in blood pressure compared with untreated OZR. However, animals from G4 (B + I) showed better control on proteinuria together with a higher creatinine clearance. Additionally, G4 showed a significant (P < 0.05) lower kidney weight; smaller glomerular area; lower glomerulosclerosis score; lower percentage of tubular atrophy, interstitial fibrosis, and interstitial alpha-SMA; lower tubular PAI-1 score; lower percentage of COL I, III, and IV in renal interstitium; and lower wall/lumen ratio in renal vessels, when compared with the other groups. OZR treated with B and/or I showed a better outcome (P < 0.01) in the carbohydrate and lipid metabolism in comparison with untreated OZR. CONCLUSION These results suggest that combined therapy using B and I is more effective than therapy with either drug at monotherapy for controlling renal damage in this animal model. In addition, data presented here reaffirm the benefit of interacting against renin-angiotensin-system (RAS) in the metabolic syndrome.
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Affiliation(s)
- Jorge Eduardo Toblli
- Laboratory of Experimental Medicine, Hospital Alemán, CONICET, Buenos Aires, Argentina.
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Liver-specific deletion of negative regulator Pten results in fatty liver and insulin hypersensitivity [corrected]. Proc Natl Acad Sci U S A 2004. [PMID: 14769918 DOI: 10.1073/pnas.0308617100;] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
In the liver, insulin controls both lipid and glucose metabolism through its cell surface receptor and intracellular mediators such as phosphatidylinositol 3-kinase and serine-threonine kinase AKT. The insulin signaling pathway is further modulated by protein tyrosine phosphatase or lipid phosphatase. Here, we investigated the function of phosphatase and tension homologue deleted on chromosome 10 (PTEN), a negative regulator of the phosphatidylinositol 3-kinase/AKT pathway, by targeted deletion of Pten in murine liver. Deletion of Pten in the liver resulted in increased fatty acid synthesis, accompanied by hepatomegaly and fatty liver phenotype. Interestingly, Pten liver-specific deletion causes enhanced liver insulin action with improved systemic glucose tolerance. Thus, deletion of Pten in the liver may provide a valuable model that permits the study of the metabolic actions of insulin signaling in the liver, and PTEN may be a promising target for therapeutic intervention for type 2 diabetes.
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Stiles B, Wang Y, Stahl A, Bassilian S, Lee WP, Kim YJ, Sherwin R, Devaskar S, Lesche R, Magnuson MA, Wu H. Liver-specific deletion of negative regulator Pten results in fatty liver and insulin hypersensitivity [corrected]. Proc Natl Acad Sci U S A 2004; 101:2082-7. [PMID: 14769918 PMCID: PMC357055 DOI: 10.1073/pnas.0308617100] [Citation(s) in RCA: 338] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
In the liver, insulin controls both lipid and glucose metabolism through its cell surface receptor and intracellular mediators such as phosphatidylinositol 3-kinase and serine-threonine kinase AKT. The insulin signaling pathway is further modulated by protein tyrosine phosphatase or lipid phosphatase. Here, we investigated the function of phosphatase and tension homologue deleted on chromosome 10 (PTEN), a negative regulator of the phosphatidylinositol 3-kinase/AKT pathway, by targeted deletion of Pten in murine liver. Deletion of Pten in the liver resulted in increased fatty acid synthesis, accompanied by hepatomegaly and fatty liver phenotype. Interestingly, Pten liver-specific deletion causes enhanced liver insulin action with improved systemic glucose tolerance. Thus, deletion of Pten in the liver may provide a valuable model that permits the study of the metabolic actions of insulin signaling in the liver, and PTEN may be a promising target for therapeutic intervention for type 2 diabetes.
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Affiliation(s)
- Bangyan Stiles
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, CA 90095, USA.
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Toblli JE, DeRosa G, Rivas C, Cao G, Piorno P, Pagano P, Forcada P. Cardiovascular protective role of a low-dose antihypertensive combination in obese Zucker rats. J Hypertens 2003; 21:611-20. [PMID: 12640256 DOI: 10.1097/00004872-200303000-00028] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Obesity, non-insulin-dependent diabetes mellitus (NIDDM) and hypertension are leading causes associated with increased cardiovascular morbidity and mortality. In modern times, the combined first line antihypertensive therapy with at least two drugs with a different mechanism of action to achieve a better blood pressure control, is increasing in acceptance worldwide. The aim of the present study was to determine possible beneficial effects of the low-dose combination (LDC) of an angiotensin-converting enzyme (ACE) inhibitor, perindopril (PER), and the diuretic indapamide (IND), regarding myocardial and vessels protection in an animal model of hypertension, obesity and NIDDM, such as the obese Zucker rat (OZR), and control lean Zucker rats (LZR). DESIGN Ten-week-old male OZR (fa/fa) and LZR (Fa/fa) were used in this study. OZR group (G1, n=8), OZR with LDC group (G2, n=8); LZR group (G3, n=8) and LZR with LDC group (G4, n=8). During 6 months, G2 and G4 received a daily dose of 1 mg/kg combination of 0.76 mg/kg PER + 0.24 mg/kg IND, (ratio of doses 0.32), by gavage, and G1 and G3 received an equal volume of vehicle throughout the experiment. In order to evaluate cardiac dimensions and left ventricular mass (LVM) transthoracic echocardiograms were performed, at baseline and at the end of the experiment. Urine and blood samples for biochemical determination were obtained. After 6 months of treatment all rats were sacrificed, hearts were harvested for light microscopy (LM), high-resolution light microscopy (HRLM), immunohistochemistry including monoclonal antibodies against transforming growth factor beta (TGFbeta1) and anti-collagen type I (COL I) and type III (COL III) and electron microscopy (EM) studies. RESULTS At the end of the study OZR treated with LDC presented: (1) lower blood pressure (128.9 +/- 4 versus 150.3 +/- 3.6 mmHg, P< 0.05); (2) smaller cardiac dimensions (P< 0.01); (3) lower LVM/100 g body weight (0.17 +/- 0.02 versus 0.30 +/- 0.05, P< 0.01); (4) higher fractional shortening (34.5 +/- 3.2 versus 23.3 +/- 5.9%, P< 0.01) than OZR untreated. Moreover, OZR that received LDC showed higher: (1) myocyte density (48 +/- 1.5 versus 20 +/- 2.5 myocytes/area, P< 0.01); (2) capillary density (30.5 +/- 3.1 versus 9.5 +/- 1.6 capillaries/area, P<0.01); (3) myofilament thickness (12.05 +/- 0.27 versus 9.83 +/- 0.39 nm, P<0.01); and lower amounts of: (1) TGFbeta1 in myocytes (P< 0.01), interstitium (P< 0.01) and vessel wall (P< 0.05); (2) COL I and COL III (P< 0.01), and COL I /COL III ratio (P< 0.01), compared with untreated OZR. Finally, OZR-treated with LDC showed not only unsubstantial modification in carbohydrate and lipid metabolism when compared with untreated OZR, but also an improvement in insulin/glucose ratio (P< 0.05). CONCLUSION These results suggest that LDC of PER + IND can control cardiovascular damage in OZR providing an additional help in the metabolic scenario likewise.
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Affiliation(s)
- Jorge E Toblli
- Laboratory of Experimental Medicine, Hospital Alemán, CONICET, Av. Pueyrredon 1640, Buenos Aires 1118, Argentina.
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