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Chiriacò M, Nesti L, Flyvbjerg A, Golay A, Nazare JA, Anderwald CH, Mitrakou A, Bizzotto R, Mari A, Natali A. At any Level of Adiposity, Relatively Elevated Leptin Concentrations Are Associated With Decreased Insulin Sensitivity. J Clin Endocrinol Metab 2024; 109:461-470. [PMID: 37650623 DOI: 10.1210/clinem/dgad505] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Revised: 06/29/2023] [Accepted: 08/30/2023] [Indexed: 09/01/2023]
Abstract
CONTEXT The impact of obesity on glucose homeostasis has high interindividual variability, which may be partially explained by different adipokine concentrations. Leptin regulates energy balance and metabolism, and although its plasma levels are proportional to fat mass, they vary significantly across individuals with the same level of adiposity. OBJECTIVE We tested whether glucose homeostasis differs in subjects with similar degrees of adiposity but different leptin levels. METHODS We analyzed 1290 healthy adults from the Relationship Between Insulin Sensitivity and Cardiovascular Disease study cohort (30-60 years; male/female, 577/713; body mass index [BMI], 25 ± 3 kg/m2) characterized for body composition and metabolic variables with a 75-g oral glucose tolerance test, euglycemic-hyperinsulinemic clamp, β-cell function, and lipidomics. RESULTS Individuals were divided into relatively high and low leptin (RHL and RLL) if they were above or below the sex-specific leptin-fat mass (%) regression. Despite similar glucose tolerance, RHL showed markedly higher fasting and oral glucose tolerance test insulin concentration (+30% and +29%, respectively; P < .0001) and secretion (+17% and +11%, respectively; P < .0001). Regardless of BMI, RHL individuals had lower whole-body (-17-23%, P < .0001) and adipose tissue insulin sensitivity (-24%, P < .0001) compared with RLL. Notably, lean RHL individuals showed similar insulin sensitivity and β-cell function to RLL individuals with overweight/obesity. CONCLUSION Subjects with leptin levels that are inappropriately elevated for their fat mass show whole-body/adipose tissue insulin resistance and hyperinsulinemia, regardless of BMI.
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Affiliation(s)
- Martina Chiriacò
- Metabolism, Nutrition, and Atherosclerosis Laboratory, Department of Clinical and Experimental Medicine, University of Pisa, 56126 Pisa, Italy
| | - Lorenzo Nesti
- Metabolism, Nutrition, and Atherosclerosis Laboratory, Department of Clinical and Experimental Medicine, University of Pisa, 56126 Pisa, Italy
| | - Allan Flyvbjerg
- Steno Diabetes Center Copenhagen, Capital Region of Denmark, 2730 Copenhagen, Denmark
| | - Alain Golay
- Department of Endocrinology, Diabetology, Nutrition and Therapeutic Education of the Patient, Geneva University Hospital, 1206 Geneva, Switzerland
| | - Julie-Anne Nazare
- Department of Human Nutrition Research Center Rhône-Alpes, CarMeN Laboratory, Université Claude Bernard Lyon 1, 69100 Villeurbanne, France
| | - Christian-Heinz Anderwald
- Obesity Research Unit, University Hospital Salzburg, Paracelsus Medical University, 5020 Salzburg, Austria
- Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, 1090 Vienna, Austria
| | - Asimina Mitrakou
- Department of Clinical Therapeutics, Alexandra Hospital, School of Medicine, National and Kapodistrian University of Athens, 115 27 Athens, Greece
| | - Roberto Bizzotto
- Institute of Neuroscience, National Research Council, 35127 Padova, Italy
| | - Andrea Mari
- Institute of Neuroscience, National Research Council, 35127 Padova, Italy
| | - Andrea Natali
- Metabolism, Nutrition, and Atherosclerosis Laboratory, Department of Clinical and Experimental Medicine, University of Pisa, 56126 Pisa, Italy
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Kim J, Oh CM, Kim H. The Interplay of Adipokines and Pancreatic Beta Cells in Metabolic Regulation and Diabetes. Biomedicines 2023; 11:2589. [PMID: 37761031 PMCID: PMC10526203 DOI: 10.3390/biomedicines11092589] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 09/19/2023] [Accepted: 09/20/2023] [Indexed: 09/29/2023] Open
Abstract
The interplay between adipokines and pancreatic beta cells, often referred to as the adipo-insular axis, plays a crucial role in regulating metabolic homeostasis. Adipokines are signaling molecules secreted by adipocytes that have profound effects on several physiological processes. Adipokines such as adiponectin, leptin, resistin, and visfatin influence the function of pancreatic beta cells. The reciprocal communication between adipocytes and beta cells is remarkable. Insulin secreted by beta cells affects adipose tissue metabolism, influencing lipid storage and lipolysis. Conversely, adipokines released from adipocytes can influence beta cell function and survival. Chronic obesity and insulin resistance can lead to the release of excess fatty acids and inflammatory molecules from the adipose tissue, contributing to beta cell dysfunction and apoptosis, which are key factors in developing type 2 diabetes. Understanding the complex interplay of the adipo-insular axis provides insights into the mechanisms underlying metabolic regulation and pathogenesis of metabolic disorders. By elucidating the molecular mediators involved in this interaction, new therapeutic targets and strategies may emerge to reduce the risk and progression of diseases, such as type 2 diabetes and its associated complications. This review summarizes the interactions between adipokines and pancreatic beta cells, and their roles in the pathogenesis of diabetes and metabolic diseases.
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Affiliation(s)
- Joon Kim
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea;
| | - Chang-Myung Oh
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea;
| | - Hyeongseok Kim
- Department of Biochemistry, College of Medicine, Chungnam National University, Daejeon 35105, Republic of Korea
- Department of Medical Science, College of Medicine, Chungnam National University, Daejeon 35105, Republic of Korea
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3
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New Insights into Adipokines in Gestational Diabetes Mellitus. Int J Mol Sci 2022; 23:ijms23116279. [PMID: 35682958 PMCID: PMC9181219 DOI: 10.3390/ijms23116279] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 05/27/2022] [Accepted: 06/01/2022] [Indexed: 12/12/2022] Open
Abstract
Gestational diabetes mellitus (GDM) is the most common metabolic disorder of pregnancy and has considerable short- and long-term consequences for the health of both the mother and the newborn. Within its pathophysiology, genetic, nutritional, epigenetic, immunological, and hormonal components have been described. Within the last two items, it is known that different hormones and cytokines secreted by adipose tissue, known collectively as adipokines, are involved in the metabolic alterations underlying GDM. Although the maternal circulating profile of adipokines in GDM has been extensively studied, and there are excellent reviews on the subject, it is in recent years that more progress has been made in the study of their expression in visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), placenta, and their concentrations in the umbilical circulation. Thus, this review compiles and organizes the most recent findings on the maternal and umbilical circulating profile and the levels of expression of adipokines in VAT, SAT, and placenta in GDM.
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Stern C, Schwarz S, Moser G, Cvitic S, Jantscher-Krenn E, Gauster M, Hiden U. Placental Endocrine Activity: Adaptation and Disruption of Maternal Glucose Metabolism in Pregnancy and the Influence of Fetal Sex. Int J Mol Sci 2021; 22:ijms222312722. [PMID: 34884524 PMCID: PMC8657775 DOI: 10.3390/ijms222312722] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 11/16/2021] [Accepted: 11/17/2021] [Indexed: 02/07/2023] Open
Abstract
The placenta is an endocrine fetal organ, which secretes a plethora of steroid- and proteo-hormones, metabolic proteins, growth factors, and cytokines in order to adapt maternal physiology to pregnancy. Central to the growth of the fetus is the supply with nutrients, foremost with glucose. Therefore, during pregnancy, maternal insulin resistance arises, which elevates maternal blood glucose levels, and consequently ensures an adequate glucose supply for the developing fetus. At the same time, maternal β-cell mass and function increase to compensate for the higher insulin demand. These adaptations are also regulated by the endocrine function of the placenta. Excessive insulin resistance or the inability to increase insulin production accordingly disrupts physiological modulation of pregnancy mediated glucose metabolism and may cause maternal gestational diabetes (GDM). A growing body of evidence suggests that this adaptation of maternal glucose metabolism differs between pregnancies carrying a girl vs. pregnancies carrying a boy. Moreover, the risk of developing GDM differs depending on the sex of the fetus. Sex differences in placenta derived hormones and bioactive proteins, which adapt and modulate maternal glucose metabolism, are likely to contribute to this sexual dimorphism. This review provides an overview on the adaptation and maladaptation of maternal glucose metabolism by placenta-derived factors, and highlights sex differences in this regulatory network.
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Affiliation(s)
- Christina Stern
- Department of Obstetrics and Gynecology, Medical University of Graz, 8036 Graz, Austria; (C.S.); (S.S.); (E.J.-K.)
| | - Sarah Schwarz
- Department of Obstetrics and Gynecology, Medical University of Graz, 8036 Graz, Austria; (C.S.); (S.S.); (E.J.-K.)
| | - Gerit Moser
- Division of Cell Biology, Histology and Embryology, Gottfried Schatz Research Center, Medical University of Graz, 8010 Graz, Austria;
| | - Silvija Cvitic
- Research Unit of Analytical Mass Spectrometry, Cell Biology and Biochemistry of Inborn Errors of Metabolism, Department of Pediatrics and Adolescent Medicine, Medical University of Graz, 8036 Graz, Austria;
| | - Evelyn Jantscher-Krenn
- Department of Obstetrics and Gynecology, Medical University of Graz, 8036 Graz, Austria; (C.S.); (S.S.); (E.J.-K.)
| | - Martin Gauster
- Division of Cell Biology, Histology and Embryology, Gottfried Schatz Research Center, Medical University of Graz, 8010 Graz, Austria;
- Correspondence: (M.G.); (U.H.); Tel.: +43-316385-71896 (M.G.); +43-136385-17837 (U.H.)
| | - Ursula Hiden
- Department of Obstetrics and Gynecology, Medical University of Graz, 8036 Graz, Austria; (C.S.); (S.S.); (E.J.-K.)
- Correspondence: (M.G.); (U.H.); Tel.: +43-316385-71896 (M.G.); +43-136385-17837 (U.H.)
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5
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Wang L, Li J, Di LJ. Glycogen synthesis and beyond, a comprehensive review of GSK3 as a key regulator of metabolic pathways and a therapeutic target for treating metabolic diseases. Med Res Rev 2021; 42:946-982. [PMID: 34729791 PMCID: PMC9298385 DOI: 10.1002/med.21867] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 08/01/2021] [Accepted: 10/24/2021] [Indexed: 12/19/2022]
Abstract
Glycogen synthase kinase‐3 (GSK3) is a highly evolutionarily conserved serine/threonine protein kinase first identified as an enzyme that regulates glycogen synthase (GS) in response to insulin stimulation, which involves GSK3 regulation of glucose metabolism and energy homeostasis. Both isoforms of GSK3, GSK3α, and GSK3β, have been implicated in many biological and pathophysiological processes. The various functions of GSK3 are indicated by its widespread distribution in multiple cell types and tissues. The studies of GSK3 activity using animal models and the observed effects of GSK3‐specific inhibitors provide more insights into the roles of GSK3 in regulating energy metabolism and homeostasis. The cross‐talk between GSK3 and some important energy regulators and sensors and the regulation of GSK3 in mitochondrial activity and component function further highlight the molecular mechanisms in which GSK3 is involved to regulate the metabolic activity, beyond its classical regulatory effect on GS. In this review, we summarize the specific roles of GSK3 in energy metabolism regulation in tissues that are tightly associated with energy metabolism and the functions of GSK3 in the development of metabolic disorders. We also address the impacts of GSK3 on the regulation of mitochondrial function, activity and associated metabolic regulation. The application of GSK3 inhibitors in clinical tests will be highlighted too. Interactions between GSK3 and important energy regulators and GSK3‐mediated responses to different stresses that are related to metabolism are described to provide a brief overview of previously less‐appreciated biological functions of GSK3 in energy metabolism and associated diseases through its regulation of GS and other functions.
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Affiliation(s)
- Li Wang
- Proteomics, Metabolomics, and Drug Development Core, Faculty of Health Sciences, University of Macau, Macau, China.,Department of Biomedical Sciences, Faculty of Health Sciences, Macau, China.,Cancer Center of the Faculty of Health Sciences, University of Macau, Macau, China.,Institute of Translational Medicine, University of Macau, Macau, China.,Ministry of Education, Frontiers Science Center for Precision Oncology, University of Macau, Macau, China
| | - Jiajia Li
- Department of Biomedical Sciences, Faculty of Health Sciences, Macau, China.,Cancer Center of the Faculty of Health Sciences, University of Macau, Macau, China.,Institute of Translational Medicine, University of Macau, Macau, China.,Ministry of Education, Frontiers Science Center for Precision Oncology, University of Macau, Macau, China
| | - Li-Jun Di
- Department of Biomedical Sciences, Faculty of Health Sciences, Macau, China.,Cancer Center of the Faculty of Health Sciences, University of Macau, Macau, China.,Institute of Translational Medicine, University of Macau, Macau, China.,Ministry of Education, Frontiers Science Center for Precision Oncology, University of Macau, Macau, China
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6
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Bake S, Pinson MR, Pandey S, Chambers JP, Mota R, Fairchild AE, Miranda RC, Sohrabji F. Prenatal alcohol-induced sex differences in immune, metabolic and neurobehavioral outcomes in adult rats. Brain Behav Immun 2021; 98:86-100. [PMID: 34390803 PMCID: PMC8591773 DOI: 10.1016/j.bbi.2021.08.207] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 07/10/2021] [Accepted: 08/06/2021] [Indexed: 12/15/2022] Open
Abstract
Prenatal alcohol exposure (PAE) can result in neurobehavioral anomalies, that may be exacerbated by co-occurring metabolic and immune system deficits. To test the hypothesis that the peripheral inflammation in adult PAE offspring is linked to poor glucose metabolism and neurocognitive deficits, pregnant Sprague-Dawley rats were exposed to ethanol vapor or ambient air during the latter half of gestation. We assessed, in adult offspring of both sexes, performance on a battery of neurocognitive behaviors, glucose tolerance, circulating and splenic immune cells by flow-cytometry, and circulating and tissue (liver, mesenteric adipose, and spleen) cytokines by multiplexed assays. PAE reduced both the ratio of spleen to body weight and splenic regulatory T-cell (Treg) numbers. PAE males, but not females exhibited an increase in circulating monocytes. Overall, PAE males exhibited a suppression of cytokine levels, while PAE females exhibited elevated cytokines in mesenteric adipose tissue (IL-6 and IL1α) and liver (IFN-γ, IL-1β, IL-13, IL-18, IL-12p70, and MCP-1), along with increased glucose intolerance. Behavioral analysis also showed sex-dependent PAE effects. PAE-males exhibited increased anxiety-like behavior while PAE-females showed decreased social interaction. PAE offspring of both sexes exhibited impaired recognition of novel objects. Multilinear regression modeling to predict the association between peripheral immune status, glucose intolerance and behavioral outcomes, showed that in PAE offspring, higher levels of adipose leptin and liver TNF- α predicted higher circulating glucose levels. Lower liver IL-1 α and higher plasma fractalkine predicted more time spent in the center of an open-field with sex being an additional predictor. Higher circulating and splenic Tregs predicted better social interaction in the PAE-offspring. Collectively, our data show that peripheral immune status is a persistent, sex-dependent predictor of glucose intolerance and neurobehavioral function in adult PAE offspring.
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Affiliation(s)
- Shameena Bake
- Women's Health in Neuroscience Program, and Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University, Bryan, TX 77807, USA
| | - Marisa R Pinson
- Women's Health in Neuroscience Program, and Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University, Bryan, TX 77807, USA
| | - Sivani Pandey
- Women's Health in Neuroscience Program, and Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University, Bryan, TX 77807, USA
| | - Joanna P Chambers
- Women's Health in Neuroscience Program, and Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University, Bryan, TX 77807, USA
| | - Roxanna Mota
- Women's Health in Neuroscience Program, and Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University, Bryan, TX 77807, USA
| | - Ashlyn E Fairchild
- Women's Health in Neuroscience Program, and Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University, Bryan, TX 77807, USA
| | - Rajesh C Miranda
- Women's Health in Neuroscience Program, and Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University, Bryan, TX 77807, USA.
| | - Farida Sohrabji
- Women's Health in Neuroscience Program, and Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University, Bryan, TX 77807, USA.
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7
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Castelli V, Brandolini L, d’Angelo M, Giorgio C, Alfonsetti M, Cocchiaro P, Lombardi F, Cimini A, Allegretti M. CXCR1/2 Inhibitor Ladarixin Ameliorates the Insulin Resistance of 3T3-L1 Adipocytes by Inhibiting Inflammation and Improving Insulin Signaling. Cells 2021; 10:cells10092324. [PMID: 34571976 PMCID: PMC8471705 DOI: 10.3390/cells10092324] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 08/25/2021] [Accepted: 08/29/2021] [Indexed: 01/02/2023] Open
Abstract
Type 2 diabetes mellitus is a severe public health issue worldwide. It displays a harmful effect on different organs as the eyes, kidneys and neural cells due to insulin resistance and high blood glucose concentrations. To date, the available treatments for this disorder remain limited. Several reports have correlated obesity with type 2 diabetes. Mainly, dysfunctional adipocytes and the regulation of high secretion of inflammatory cytokines are the crucial links between obesity and insulin resistance. Several clinical and epidemiological studies have also correlated the onset of type 2 diabetes with inflammation, which is now indicated as a new target for type 2 diabetes treatment. Thus, it appears essential to discover new drugs able to inhibit the secretion of proinflammatory adipocytokines in type 2 diabetes. Adipocytes produce inflammatory cytokines in response to inflammation or high glucose levels. Once activated by a specific ligand, CXCR1 and CXCR2 mediate some cytokines’ effects by activating an intracellular signal cascade once activated by a specific ligand. Therefore, it is conceivable to hypothesize that a specific antagonist of these receptors may ameliorate type 2 diabetes and glucose metabolism. Herein, differentiated 3T3-L1-adipocytes were subjected to high glucose or inflammatory conditions or the combination of both and then treated with ladarixin, a CXCR1/2 inhibitor. The results obtained point towards the positive regulation by ladarixin on insulin sensitivity, glucose transporters GLUT1 and GLUT4, cytokine proteome profile and lipid metabolism, thus suggesting ladarixin as a potentially helpful treatment in type 2 diabetes mellitus and obesity.
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Affiliation(s)
- Vanessa Castelli
- Department of Life, Health and Environmental Sciences, University of L’Aquila, 67100 L’Aquila, Italy; (V.C.); (M.d.); (M.A.); (F.L.)
| | - Laura Brandolini
- Dompè Farmaceutici SpA, Via Campo di Pile, 67100 L’Aquila, Italy; (L.B.); (C.G.); (P.C.)
| | - Michele d’Angelo
- Department of Life, Health and Environmental Sciences, University of L’Aquila, 67100 L’Aquila, Italy; (V.C.); (M.d.); (M.A.); (F.L.)
| | - Cristina Giorgio
- Dompè Farmaceutici SpA, Via Campo di Pile, 67100 L’Aquila, Italy; (L.B.); (C.G.); (P.C.)
| | - Margherita Alfonsetti
- Department of Life, Health and Environmental Sciences, University of L’Aquila, 67100 L’Aquila, Italy; (V.C.); (M.d.); (M.A.); (F.L.)
| | - Pasquale Cocchiaro
- Dompè Farmaceutici SpA, Via Campo di Pile, 67100 L’Aquila, Italy; (L.B.); (C.G.); (P.C.)
| | - Francesca Lombardi
- Department of Life, Health and Environmental Sciences, University of L’Aquila, 67100 L’Aquila, Italy; (V.C.); (M.d.); (M.A.); (F.L.)
| | - Annamaria Cimini
- Department of Life, Health and Environmental Sciences, University of L’Aquila, 67100 L’Aquila, Italy; (V.C.); (M.d.); (M.A.); (F.L.)
- Sbarro Institute for Cancer Research and Molecular Medicine and Center for Biotechnology, Temple University, Philadelphia, PA 19122, USA
- Correspondence: (A.C.); (M.A.)
| | - Marcello Allegretti
- Dompè Farmaceutici SpA, Via Campo di Pile, 67100 L’Aquila, Italy; (L.B.); (C.G.); (P.C.)
- Correspondence: (A.C.); (M.A.)
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8
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Schäfer AL, Eichhorst A, Hentze C, Kraemer AN, Amend A, Sprenger DTL, Fluhr C, Finzel S, Daniel C, Salzer U, Rizzi M, Voll RE, Chevalier N. Low Dietary Fiber Intake Links Development of Obesity and Lupus Pathogenesis. Front Immunol 2021; 12:696810. [PMID: 34335609 PMCID: PMC8320762 DOI: 10.3389/fimmu.2021.696810] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Accepted: 06/23/2021] [Indexed: 12/12/2022] Open
Abstract
Changed dietary habits in Western countries such as reduced fiber intake represent an important lifestyle factor contributing to the increase in inflammatory immune-mediated diseases. The mode of action of beneficial fiber effects is not fully elucidated, but short-chain fatty acids (SCFA) and gut microbiota have been implicated. The aim of this study was to explore the impact of dietary fiber on lupus pathology and to understand underlying mechanisms. Here, we show that in lupus-prone NZB/WF1 mice low fiber intake deteriorates disease progression reflected in accelerated mortality, autoantibody production and immune dysregulation. In contrast to our original assumption, microbiota suppression by antibiotics or direct SCFA feeding did not influence the course of lupus-like disease. Mechanistically, our data rather indicate that in low fiber-fed mice, an increase in white adipose tissue mass, fat-inflammation and a disrupted intestinal homeostasis go along with systemic, low-grade inflammation driving autoimmunity. The links between obesity, intestinal leakage and low-grade inflammation were confirmed in human samples, while adaptive immune activation predominantly correlated with lupus activity. We further propose that an accelerated gastro-intestinal passage along with energy dilution underlies fiber-mediated weight regulation. Thus, our data highlight the often-overlooked effects of dietary fiber on energy homeostasis and obesity prevention. Further, they provide insight into how intricately the pathologies of inflammatory immune-mediated conditions, such as obesity and autoimmunity, might be interlinked, possibly sharing common pathways.
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MESH Headings
- Adaptive Immunity
- Adipose Tissue, White/immunology
- Adipose Tissue, White/metabolism
- Adipose Tissue, White/pathology
- Adiposity
- Adolescent
- Adult
- Aged
- Aged, 80 and over
- Animal Feed
- Animals
- Autoantibodies/blood
- Autoimmunity
- Case-Control Studies
- Dietary Fiber/administration & dosage
- Dietary Fiber/deficiency
- Disease Models, Animal
- Disease Progression
- Energy Metabolism
- Female
- Humans
- Inflammation Mediators/metabolism
- Intestinal Mucosa/immunology
- Intestinal Mucosa/metabolism
- Intestinal Mucosa/pathology
- Lupus Erythematosus, Systemic/etiology
- Lupus Erythematosus, Systemic/immunology
- Lupus Erythematosus, Systemic/metabolism
- Lupus Erythematosus, Systemic/pathology
- Male
- Mice, Inbred NZB
- Middle Aged
- Nutritive Value
- Obesity/etiology
- Obesity/immunology
- Obesity/metabolism
- Obesity/pathology
- Permeability
- Young Adult
- Mice
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Affiliation(s)
- Anna-Lena Schäfer
- Department of Rheumatology and Clinical Immunology, University Medical Centre Freiburg, Freiburg, Germany
| | - Alexandra Eichhorst
- Department of Rheumatology and Clinical Immunology, University Medical Centre Freiburg, Freiburg, Germany
| | - Carolin Hentze
- Department of Rheumatology and Clinical Immunology, University Medical Centre Freiburg, Freiburg, Germany
| | - Antoine N. Kraemer
- Department of Rheumatology and Clinical Immunology, University Medical Centre Freiburg, Freiburg, Germany
| | - Anaïs Amend
- Department of Rheumatology and Clinical Immunology, University Medical Centre Freiburg, Freiburg, Germany
| | - Dalina T. L. Sprenger
- Department of Rheumatology and Clinical Immunology, University Medical Centre Freiburg, Freiburg, Germany
| | - Cara Fluhr
- Department of Rheumatology and Clinical Immunology, University Medical Centre Freiburg, Freiburg, Germany
| | - Stephanie Finzel
- Department of Rheumatology and Clinical Immunology, University Medical Centre Freiburg, Freiburg, Germany
| | - Christoph Daniel
- Department of Nephropathology, Friedrich-Alexander University (FAU) of Erlangen-Nuremberg, Erlangen, Germany
| | - Ulrich Salzer
- Department of Rheumatology and Clinical Immunology, University Medical Centre Freiburg, Freiburg, Germany
| | - Marta Rizzi
- Department of Rheumatology and Clinical Immunology, University Medical Centre Freiburg, Freiburg, Germany
| | - Reinhard E. Voll
- Department of Rheumatology and Clinical Immunology, University Medical Centre Freiburg, Freiburg, Germany
| | - Nina Chevalier
- Department of Rheumatology and Clinical Immunology, University Medical Centre Freiburg, Freiburg, Germany
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Adipose Tissue Immunomodulation and Treg/Th17 Imbalance in the Impaired Glucose Metabolism of Children with Obesity. CHILDREN-BASEL 2021; 8:children8070554. [PMID: 34199040 PMCID: PMC8305706 DOI: 10.3390/children8070554] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 06/18/2021] [Accepted: 06/25/2021] [Indexed: 12/12/2022]
Abstract
In the last few decades, obesity has increased dramatically in pediatric patients. Obesity is a chronic disease correlated with systemic inflammation, characterized by the presence of CD4 and CD8 T cell infiltration and modified immune response, which contributes to the development of obesity related diseases and metabolic disorders, including impaired glucose metabolism. In particular, Treg and Th17 cells are dynamically balanced under healthy conditions, but imbalance occurs in inflammatory and pathological states, such as obesity. Some studies demonstrated that peripheral Treg and Th17 cells exhibit increased imbalance with worsening of glucose metabolic dysfunction, already in children with obesity. In this review, we considered the role of adipose tissue immunomodulation and the potential role played by Treg/T17 imbalance on the impaired glucose metabolism in pediatric obesity. In the patient care, immune monitoring could play an important role to define preventive strategies of pediatric metabolic disease treatments.
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Rajesh Y, Sarkar D. Association of Adipose Tissue and Adipokines with Development of Obesity-Induced Liver Cancer. Int J Mol Sci 2021; 22:ijms22042163. [PMID: 33671547 PMCID: PMC7926723 DOI: 10.3390/ijms22042163] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 02/01/2021] [Accepted: 02/02/2021] [Indexed: 12/20/2022] Open
Abstract
Obesity is rapidly dispersing all around the world and is closely associated with a high risk of metabolic diseases such as insulin resistance, dyslipidemia, and nonalcoholic fatty liver disease (NAFLD), leading to carcinogenesis, especially hepatocellular carcinoma (HCC). It results from an imbalance between food intake and energy expenditure, leading to an excessive accumulation of adipose tissue (AT). Adipocytes play a substantial role in the tumor microenvironment through the secretion of several adipokines, affecting cancer progression, metastasis, and chemoresistance via diverse signaling pathways. AT is considered an endocrine organ owing to its ability to secrete adipokines, such as leptin, adiponectin, resistin, and a plethora of inflammatory cytokines, which modulate insulin sensitivity and trigger chronic low-grade inflammation in different organs. Even though the precise mechanisms are still unfolding, it is now established that the dysregulated secretion of adipokines by AT contributes to the development of obesity-related metabolic disorders. This review focuses on several obesity-associated adipokines and their impact on obesity-related metabolic diseases, subsequent metabolic complications, and progression to HCC, as well as their role as potential therapeutic targets. The field is rapidly developing, and further research is still required to fully understand the underlying mechanisms for the metabolic actions of adipokines and their role in obesity-associated HCC.
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Affiliation(s)
- Yetirajam Rajesh
- Department of Human and Molecular Genetics, Virginia Commonwealth University, Richmond, VA 23298, USA;
| | - Devanand Sarkar
- Massey Cancer Center, Department of Human and Molecular Genetics, VCU Institute of Molecular Medicine (VIMM), Virginia Commonwealth University, Richmond, VA 23298, USA
- Correspondence: ; Tel.: +1-804-827-2339
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11
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Pereira S, Cline DL, Glavas MM, Covey SD, Kieffer TJ. Tissue-Specific Effects of Leptin on Glucose and Lipid Metabolism. Endocr Rev 2021; 42:1-28. [PMID: 33150398 PMCID: PMC7846142 DOI: 10.1210/endrev/bnaa027] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Indexed: 12/18/2022]
Abstract
The discovery of leptin was intrinsically associated with its ability to regulate body weight. However, the effects of leptin are more far-reaching and include profound glucose-lowering and anti-lipogenic effects, independent of leptin's regulation of body weight. Regulation of glucose metabolism by leptin is mediated both centrally and via peripheral tissues and is influenced by the activation status of insulin signaling pathways. Ectopic fat accumulation is diminished by both central and peripheral leptin, an effect that is beneficial in obesity-associated disorders. The magnitude of leptin action depends upon the tissue, sex, and context being examined. Peripheral tissues that are of particular relevance include the endocrine pancreas, liver, skeletal muscle, adipose tissues, immune cells, and the cardiovascular system. As a result of its potent metabolic activity, leptin is used to control hyperglycemia in patients with lipodystrophy and is being explored as an adjunct to insulin in patients with type 1 diabetes. To fully understand the role of leptin in physiology and to maximize its therapeutic potential, the mechanisms of leptin action in these tissues needs to be further explored.
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Affiliation(s)
- Sandra Pereira
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, Canada
| | - Daemon L Cline
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, Canada
| | - Maria M Glavas
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, Canada
| | - Scott D Covey
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, Canada
| | - Timothy J Kieffer
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, Canada.,Department of Surgery, University of British Columbia, Vancouver, Canada.,School of Biomedical Engineering, University of British Columbia, Vancouver, Canada
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12
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Moinard A, Payen C, Ouguerram K, André A, Hernandez J, Drut A, Biourge VC, Suchodolski JS, Flanagan J, Nguyen P, Leray V. Effects of High-Fat Diet at Two Energetic Levels on Fecal Microbiota, Colonic Barrier, and Metabolic Parameters in Dogs. Front Vet Sci 2020; 7:566282. [PMID: 33102570 PMCID: PMC7545960 DOI: 10.3389/fvets.2020.566282] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 08/21/2020] [Indexed: 12/22/2022] Open
Abstract
Increased consumption of energy-rich foods is a key factor in overweight, obesity, and associated metabolic disorders. This would be, at least in part, related to microbiota disturbance. In rodent models of obesity, microbiota disruption has been associated with alteration of the intestinal barrier, endotoxemia, inflammation grade, and insulin sensitivity. The aim of the present study was to assess the effects of a high-fat diet (HFD), fed at two energetic levels, on microbiota, intestinal barrier, and inflammatory and metabolic parameters in dogs. A HFD (33% fat as fed, 4,830 kcal/kg) was given to 24 healthy Beagle dogs at 100% (HF-100; n = 8) and at 150% (HF-150; n = 16) of their maintenance energy requirements for 8 weeks. Analysis of similarity revealed a significant difference in gut microbiota β-diversity following the diet compared to week 0 in both groups while α-diversity was lower only in the HF-150 group. Firmicutes/Bacteroidetes ratio was higher in the HF-150 group compared to the HF-100 group at weeks 2 and 8. A reduction in insulin sensitivity was observed over time in the HF150 group. Neither endotoxemia nor inflammation was observed in either group, did not find supporting data for the hypothesis that the microbiota is involved in the decline of insulin sensitivity through metabolic endotoxemia and low-grade inflammation. Colonic permeability was increased at week 4 in both groups and returned to initial levels at week 8, and was associated with modifications to the expression of genes involved in colonic barrier function. The increase in intestinal permeability may have been caused by the altered intestinal microbiota and increased expression of genes encoding tight junction proteins might indicate a compensatory mechanism to restore normal permeability. Although simultaneous changes to the microbiota, barrier permeability, inflammatory, and metabolic status have not been observed, such a causal link cannot be excluded in dogs overfed on a HFD. Further studies are necessary to better understand the link between HFD, intestinal microbiota and the host.
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Affiliation(s)
- Alex Moinard
- Nutrition, PhysioPathology and Pharmacology Unit (NP3), Oniris, College of Veterinary Medicine, Food Sciences and Engineering, CRNH, Nantes, France
| | - Cyrielle Payen
- Nutrition, PhysioPathology and Pharmacology Unit (NP3), Oniris, College of Veterinary Medicine, Food Sciences and Engineering, CRNH, Nantes, France
| | - Khadija Ouguerram
- UMR 1280 Physiopathology of Nutritional Adaptations (PhAN), INRAE, CRNH, West Human Nutrition Research Center, CHU, Nantes, France
| | - Agnès André
- Nutrition, PhysioPathology and Pharmacology Unit (NP3), Oniris, College of Veterinary Medicine, Food Sciences and Engineering, CRNH, Nantes, France
| | - Juan Hernandez
- USC 1383 Cellular and Molecular Immunoendocrinology (IECM), INRAE, Oniris, College of Veterinary Medicine, Food Sciences and Engineering, Nantes, France
| | - Amandine Drut
- Nutrition, PhysioPathology and Pharmacology Unit (NP3), Oniris, College of Veterinary Medicine, Food Sciences and Engineering, CRNH, Nantes, France
| | | | - Jan S Suchodolski
- Gastrointestinal Laboratory, Texas A&M University, College Station, TX, United States
| | | | - Patrick Nguyen
- Nutrition, PhysioPathology and Pharmacology Unit (NP3), Oniris, College of Veterinary Medicine, Food Sciences and Engineering, CRNH, Nantes, France
| | - Véronique Leray
- Nutrition, PhysioPathology and Pharmacology Unit (NP3), Oniris, College of Veterinary Medicine, Food Sciences and Engineering, CRNH, Nantes, France
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13
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Kim Y, Kim OK. Potential Roles of Adipocyte Extracellular Vesicle-Derived miRNAs in Obesity-Mediated Insulin Resistance. Adv Nutr 2020; 12:566-574. [PMID: 32879940 PMCID: PMC8009749 DOI: 10.1093/advances/nmaa105] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 07/13/2020] [Accepted: 08/05/2020] [Indexed: 02/06/2023] Open
Abstract
Recently, extracellular microRNAs (miRNAs) from adipose tissue have been shown to be involved in the development of insulin resistance. Here, we summarize several mechanisms explaining the pathogenesis of obesity-induced insulin resistance and associated changes in the expression of obesity-associated extracellular miRNAs. We discuss how miRNAs, particularly miR-27a, miR-34a, miR-141-3p, miR-155, miR210, and miR-222, in extracellular vesicles secreted from the adipose tissue can affect the insulin signaling pathway in metabolic tissue. Understanding the role of these miRNAs will further support the development of therapeutics for obesity and metabolic disorders such as type 2 diabetes.
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Affiliation(s)
- Yujeong Kim
- Division of Food and Nutrition, Chonnam National University, Gwangju, Republic of Korea
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14
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Funcke JB, Scherer PE. Beyond adiponectin and leptin: adipose tissue-derived mediators of inter-organ communication. J Lipid Res 2019; 60:1648-1684. [PMID: 31209153 PMCID: PMC6795086 DOI: 10.1194/jlr.r094060] [Citation(s) in RCA: 176] [Impact Index Per Article: 35.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 06/17/2019] [Indexed: 01/10/2023] Open
Abstract
The breakthrough discoveries of leptin and adiponectin more than two decades ago led to a widespread recognition of adipose tissue as an endocrine organ. Many more adipose tissue-secreted signaling mediators (adipokines) have been identified since then, and much has been learned about how adipose tissue communicates with other organs of the body to maintain systemic homeostasis. Beyond proteins, additional factors, such as lipids, metabolites, noncoding RNAs, and extracellular vesicles (EVs), released by adipose tissue participate in this process. Here, we review the diverse signaling mediators and mechanisms adipose tissue utilizes to relay information to other organs. We discuss recently identified adipokines (proteins, lipids, and metabolites) and briefly outline the contributions of noncoding RNAs and EVs to the ever-increasing complexities of adipose tissue inter-organ communication. We conclude by reflecting on central aspects of adipokine biology, namely, the contribution of distinct adipose tissue depots and cell types to adipokine secretion, the phenomenon of adipokine resistance, and the capacity of adipose tissue to act both as a source and sink of signaling mediators.
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Affiliation(s)
- Jan-Bernd Funcke
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX
| | - Philipp E Scherer
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX
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15
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Bonzón-Kulichenko E, Moltó E, Pintado C, Fernández A, Arribas C, Schwudke D, Gallardo N, Shevchenko A, Andrés A. Changes in Visceral Adipose Tissue Plasma Membrane Lipid Composition in Old Rats Are Associated With Adipocyte Hypertrophy With Aging. J Gerontol A Biol Sci Med Sci 2019; 73:1139-1146. [PMID: 29668887 DOI: 10.1093/gerona/gly081] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 04/13/2018] [Indexed: 12/17/2022] Open
Abstract
Increased adiposity, through adipocyte hypertrophy, and/or hyperplasia, characterizes aging and obesity. Both are leptin-resistant states, associated with disturbed lipid metabolism, reduced insulin sensitivity and inflammation. Nevertheless, fat tissue dysfunction appears earlier in obesity than in normal aging. In contrast, lipodystrophy is accompanied by diabetes, and improving the fat cell capacity to expand rescues the diabetic phenotype. Fat tissue dysfunction is extensively studied in the diet-induced obesity, but remains relatively neglected in the aging-associated obesity. In the Wistar rat, as occurs in humans, early or middle aging is accompanied by an increase in adiposity. Using this experimental model, we describe the molecular mechanisms contributing to the white adipose tissue (WAT) hypertrophy. WAT from middle-old age rats is characterized by decreased basal lipogenesis and lipolysis, increased esterification, as demonstrated by the higher TAG and cholesterol content in visceral WAT, and the maintenance of total ceramide levels within normal values. In addition, we describe alterations in the adipose tissue plasma membrane lipid composition, as increased total ether-phosphatidylcholine, sphingomyelin, and free cholesterol levels that favor an enlarged fat cell size with aging. All these metabolic changes may be regarded as a survival advantage that prevents the aged rats from becoming overtly diabetic.
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Affiliation(s)
- Elena Bonzón-Kulichenko
- Área de Bioquímica, Facultad de Ciencias y Tecnologías Químicas, Centro Regional de Investigaciones Biomédicas (CRIB), Universidad de Castilla-La Mancha, Ciudad Real, Spain
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain
| | - Eduardo Moltó
- Área de Bioquímica, Facultad de Ciencias Medioambientales y Bioquímica, Centro Regional de Investigaciones Biomédicas (CRIB), Universidad de Castilla-La Mancha, Toledo, Spain
| | - Cristina Pintado
- Área de Bioquímica, Facultad de Ciencias Medioambientales y Bioquímica, Centro Regional de Investigaciones Biomédicas (CRIB), Universidad de Castilla-La Mancha, Toledo, Spain
| | - Alejandro Fernández
- Área de Bioquímica, Facultad de Ciencias y Tecnologías Químicas, Centro Regional de Investigaciones Biomédicas (CRIB), Universidad de Castilla-La Mancha, Ciudad Real, Spain
| | - Carmen Arribas
- Área de Bioquímica, Facultad de Ciencias Medioambientales y Bioquímica, Centro Regional de Investigaciones Biomédicas (CRIB), Universidad de Castilla-La Mancha, Toledo, Spain
| | - Dominik Schwudke
- Division of Bioanalytical Chemistry, Priority Area Infections, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, Germany
| | - Nilda Gallardo
- Área de Bioquímica, Facultad de Ciencias y Tecnologías Químicas, Centro Regional de Investigaciones Biomédicas (CRIB), Universidad de Castilla-La Mancha, Ciudad Real, Spain
| | - Andrej Shevchenko
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Antonio Andrés
- Área de Bioquímica, Facultad de Ciencias y Tecnologías Químicas, Centro Regional de Investigaciones Biomédicas (CRIB), Universidad de Castilla-La Mancha, Ciudad Real, Spain
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16
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Wang HY, Capuano AW, Khan A, Pei Z, Lee KC, Bennett DA, Ahima RS, Arnold SE, Arvanitakis Z. Insulin and adipokine signaling and their cross-regulation in postmortem human brain. Neurobiol Aging 2019; 84:119-130. [PMID: 31539648 DOI: 10.1016/j.neurobiolaging.2019.08.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 08/09/2019] [Accepted: 08/13/2019] [Indexed: 12/14/2022]
Abstract
Aberrant insulin and adipokine signaling has been implicated in cognitive decline associated with both type 2 diabetes mellitus and neurodegenerative diseases. We established methods that reliably measure insulin, adiponectin and leptin signaling, and their crosstalk, in thawed postmortem mid-frontal cortical tissue from cognitively normal older subjects with a short postmortem interval. Insulin-evoked insulin receptor (IR) activation increases activated, tyrosine-phosphorylated IRβ on tyrosine residues 960, 1150, and 1151, insulin receptor substrate-1 recruitment to IRβ and phosphorylated RAC-α-serine/threonine-protein kinase. Adiponectin augments, but leptin inhibits, insulin signaling. Adiponectin activates adiponectin receptors to induce APPL1 binding to adiponectin receptor 1 and 2 and T-cadherin and downstream adenosine monophosphate-dependent protein kinase phosphorylation. Insulin inhibited adiponectin-induced signaling. In addition, leptin-induced leptin receptor (OB-R) signaling promotes Janus kinase 2 recruitment to OB-R and Janus kinase 2 and downstream signal transducer and activator of transcription 3 phosphorylation. Insulin enhanced leptin signaling. These data demonstrate insulin and adipokine signaling interactions in human brain. Future studies can use these methods to examine insulin, adiponectin, and leptin metabolic dysregulation in aging and disease states, such as type 2 diabetes and Alzheimer's disease-related dementias.
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Affiliation(s)
- Hoau-Yan Wang
- Department of Molecular, Cellular and Biomedical Sciences, City University of New York School of Medicine, New York, NY, USA; Department of Biology, Neuroscience Program, Graduate School of The City University of New York, New York, NY, USA.
| | - Ana W Capuano
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Amber Khan
- Department of Molecular, Cellular and Biomedical Sciences, City University of New York School of Medicine, New York, NY, USA; Department of Biology, Neuroscience Program, Graduate School of The City University of New York, New York, NY, USA
| | - Zhe Pei
- Department of Molecular, Cellular and Biomedical Sciences, City University of New York School of Medicine, New York, NY, USA
| | - Kuo-Chieh Lee
- Department of Molecular, Cellular and Biomedical Sciences, City University of New York School of Medicine, New York, NY, USA
| | - David A Bennett
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Rexford S Ahima
- Division of Endocrinology, Diabetes and Metabolism, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Steven E Arnold
- Department of Neurology and the Massachusetts Alzheimer's Disease Research Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Zoe Arvanitakis
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
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17
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Gonzalez LL, Garrie K, Turner MD. Type 2 diabetes - An autoinflammatory disease driven by metabolic stress. Biochim Biophys Acta Mol Basis Dis 2018; 1864:3805-3823. [PMID: 30251697 DOI: 10.1016/j.bbadis.2018.08.034] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 08/27/2018] [Indexed: 02/06/2023]
Abstract
Type 2 diabetes has traditionally been viewed as a metabolic disorder characterised by chronic high glucose levels, insulin resistance, and declining insulin secretion from the pancreas. Modern lifestyle, with abundant nutrient supply and reduced physical activity, has resulted in dramatic increases in the rates of obesity-associated disease conditions, including diabetes. The associated excess of nutrients induces a state of systemic low-grade chronic inflammation that results from production and secretion of inflammatory mediators from the expanded pool of activated adipocytes. Here, we review the mechanisms by which obesity induces adipose tissue dysregulation, detailing the roles of adipose tissue secreted factors and their action upon other cells and tissues central to glucose homeostasis and type 2 diabetes. Furthermore, given the emerging importance of adipokines, cytokines and chemokines in disease progression, we suggest that type 2 diabetes should now be viewed as an autoinflammatory disease, albeit one that is driven by metabolic dysregulation.
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Affiliation(s)
- Laura L Gonzalez
- Interdisciplinary Biomedical Research Centre, School of Science and Technology, Nottingham Trent University, Clifton, Nottingham NG11 8NS, United Kingdom
| | - Karin Garrie
- Interdisciplinary Biomedical Research Centre, School of Science and Technology, Nottingham Trent University, Clifton, Nottingham NG11 8NS, United Kingdom
| | - Mark D Turner
- Interdisciplinary Biomedical Research Centre, School of Science and Technology, Nottingham Trent University, Clifton, Nottingham NG11 8NS, United Kingdom.
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18
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Gupta A, Beg M, Kumar D, Shankar K, Varshney S, Rajan S, Srivastava A, Singh K, Sonkar S, Mahdi AA, Dikshit M, Gaikwad AN. Chronic hyper-leptinemia induces insulin signaling disruption in adipocytes: Implications of NOS2. Free Radic Biol Med 2017; 112:93-108. [PMID: 28739528 DOI: 10.1016/j.freeradbiomed.2017.07.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 07/11/2017] [Accepted: 07/20/2017] [Indexed: 01/12/2023]
Abstract
Leptin, following its discovery, has developed a formidable interest in the scientific community to delineate its contribution towards overall metabolic homeostasis. Contradictory reports have been published on leptin administration effects on whole body insulin sensitivity. Following late reports, we surveyed human serum leptin levels along with other metabolic parameters including BMI and HOMA-IR. We found a positive correlation between leptin levels and insulin resistance parameters. Considering the presence of the long form of leptin receptor on adipocytes, we explored the effects of chronic physiological hyper-leptinemic exposure on adipocyte insulin sensitivity. Chronic leptin (50ng/ml) treatment in 3T3-L1 adipocytes decreased insulin-induced phosphorylation of nodal insulin signaling proteins along with reduced glucose uptake. Metabolic flux studies indicated mitochondrial dysfunction and reduced oxygen consumption rate. Leptin treatment also increased both cellular and mitochondrial superoxide levels concomitant to increased expression of nitric oxide synthase-2 (NOS2). Further, pharmacological depletion of NOS2 reversed leptin mediated effects on insulin signaling. In-vivo implantation of leptin osmotic pumps in C57BL/6 mice also decreased insulin responsiveness. Interestingly, these effects were lacking in NOS2 knockout strain. In conclusion, our studies put forward a potential link between leptin and adipocyte insulin responsiveness in an NOS2 dependent manner.
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Affiliation(s)
- Abhishek Gupta
- Division of Pharmacology, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Muheeb Beg
- Division of Pharmacology, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Durgesh Kumar
- Division of Pharmacology, CSIR-Central Drug Research Institute, Lucknow 226031, India; Academy of Scientific and Innovative Research, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Kripa Shankar
- Division of Pharmacology, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Salil Varshney
- Division of Pharmacology, CSIR-Central Drug Research Institute, Lucknow 226031, India; Academy of Scientific and Innovative Research, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Sujith Rajan
- Division of Pharmacology, CSIR-Central Drug Research Institute, Lucknow 226031, India; Academy of Scientific and Innovative Research, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Ankita Srivastava
- Division of Pharmacology, CSIR-Central Drug Research Institute, Lucknow 226031, India; Academy of Scientific and Innovative Research, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Kalpana Singh
- Department of Biochemistry, King George's Medical University, Lucknow 226003, India
| | - Satyendra Sonkar
- Department of Internal Medicine, King George's Medical University, Lucknow 226003, India
| | - Abbas Ali Mahdi
- Department of Biochemistry, King George's Medical University, Lucknow 226003, India
| | - Madhu Dikshit
- Division of Pharmacology, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Anil Nilkanth Gaikwad
- Division of Pharmacology, CSIR-Central Drug Research Institute, Lucknow 226031, India.
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19
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Amor S, Martín-Carro B, Rubio C, Carrascosa JM, Hu W, Huang Y, García-Villalón AL, Granado M. Study of insulin vascular sensitivity in aortic rings and endothelial cells from aged rats subjected to caloric restriction: Role of perivascular adipose tissue. Exp Gerontol 2017; 109:126-136. [PMID: 29055722 DOI: 10.1016/j.exger.2017.10.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 10/15/2017] [Accepted: 10/16/2017] [Indexed: 02/05/2023]
Abstract
The prevalence of metabolic syndrome is dramatically increasing among elderly population. Metabolic syndrome in aged individuals is associated with hyperinsulinemia and insulin resistance both in metabolic tissues and in the cardiovascular system, with this fact being associated with the cardiometabolic alterations associated to this condition. Caloric restriction (CR) improves insulin sensitivity and is one of the dietetic strategies most commonly used to enlarge life and to prevent aging induced cardiovascular alterations. The aim of this study was to analyze the possible beneficial effects of CR in aging-induced vascular insulin resistance both in aortic rings and in primary culture of endothelial cells. In addition, the inflammatory profile of perivascular adipose tissue (PVAT) and its possible role in the impairment of vascular insulin sensitivity associated with aging was also assessed. Three experimental groups of male Wistar rats were used: 3 (3m), 24 (24m) fed ad libitum and 24months old rats subjected to 20% CR during their three last months of life (24m-CR). Aorta rings surrounded or not by PVAT were mounted in an organ bath and precontracted with phenylephrine (10-7.5M). Changes in isometric tension were recorded in response to cumulative insulin concentrations (10-8-10-5.5M) in the presence or absence of L-NAME (10-4M). Aortic rings and primary aortic endothelial cells were incubated in presence/absence of insulin (10-7M) and the activation of the PI3K/Akt and MAPK pathways as well as nitrite and nitrates concentrations and the mRNA levels of eNOS, insulin receptor, and GLUT-4 were assessed. CR prevented the aging-induced decrease in the vasodilator response to insulin and the aging-induced increase in the vasoconstrictor response to high insulin concentrations. Changes between 24m and 24m-CR aorta rings were abolished in the presence of L-NAME. CR induced-improvement in insulin vascular sensitivity was related with activation of the PI3K/Akt both in aortic rings and in aortic endothelial cells in response to insulin. CR attenuated the overexpression of iNOS, TNF-α and IL-1β in the PVAT of aged rats although aortic rings surrounded by PVAT from 24m rats showed and increased vasorelaxation in response to insulin compared to aortic rings from 3m and 24m-CR rats. In conclusion, a moderate protocol of CR improves insulin vascular sensitivity and prevents the aging induced overexpression of pro-inflammatory cytokines in PVAT.
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Affiliation(s)
- S Amor
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Spain
| | - B Martín-Carro
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Spain
| | - C Rubio
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad Autónoma de Madrid, Spain
| | - J M Carrascosa
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad Autónoma de Madrid, Spain
| | - W Hu
- School of Biomedical Sciences, Institute of Vascular Medicine, Faculty of Medicine, Chinese University of Hong Kong, China
| | - Y Huang
- School of Biomedical Sciences, Institute of Vascular Medicine, Faculty of Medicine, Chinese University of Hong Kong, China
| | - A L García-Villalón
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Spain
| | - M Granado
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, Madrid, Spain.
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20
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D'souza AM, Neumann UH, Glavas MM, Kieffer TJ. The glucoregulatory actions of leptin. Mol Metab 2017; 6:1052-1065. [PMID: 28951828 PMCID: PMC5605734 DOI: 10.1016/j.molmet.2017.04.011] [Citation(s) in RCA: 122] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 04/18/2017] [Accepted: 04/24/2017] [Indexed: 12/28/2022] Open
Abstract
Background The hormone leptin is an important regulator of metabolic homeostasis, able to inhibit food intake and increase energy expenditure. Leptin can also independently lower blood glucose levels, particularly in hyperglycemic models of leptin or insulin deficiency. Despite significant efforts and relevance to diabetes, the mechanisms by which leptin acts to regulate blood glucose levels are not fully understood. Scope of review Here we assess literature relevant to the glucose lowering effects of leptin. Leptin receptors are widely expressed in multiple cell types, and we describe both peripheral and central effects of leptin that may be involved in lowering blood glucose. In addition, we summarize the potential clinical application of leptin in regulating glucose homeostasis. Major conclusions Leptin exerts a plethora of metabolic effects on various tissues including suppressing production of glucagon and corticosterone, increasing glucose uptake, and inhibiting hepatic glucose output. A more in-depth understanding of the mechanisms of the glucose-lowering actions of leptin may reveal new strategies to treat metabolic disorders.
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Affiliation(s)
- Anna M D'souza
- Department of Cellular and Physiological Sciences, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia V6T 1Z3, Canada
| | - Ursula H Neumann
- Department of Cellular and Physiological Sciences, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia V6T 1Z3, Canada
| | - Maria M Glavas
- Department of Cellular and Physiological Sciences, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia V6T 1Z3, Canada
| | - Timothy J Kieffer
- Department of Cellular and Physiological Sciences, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia V6T 1Z3, Canada.,Department of Surgery, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia V6T 1Z3, Canada
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21
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Stern JH, Rutkowski JM, Scherer PE. Adiponectin, Leptin, and Fatty Acids in the Maintenance of Metabolic Homeostasis through Adipose Tissue Crosstalk. Cell Metab 2016; 23:770-84. [PMID: 27166942 PMCID: PMC4864949 DOI: 10.1016/j.cmet.2016.04.011] [Citation(s) in RCA: 677] [Impact Index Per Article: 84.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Metabolism research has made tremendous progress over the last several decades in establishing the adipocyte as a central rheostat in the regulation of systemic nutrient and energy homeostasis. Operating at multiple levels of control, the adipocyte communicates with organ systems to adjust gene expression, glucoregulatory hormone exocytosis, enzymatic reactions, and nutrient flux to equilibrate the metabolic demands of a positive or negative energy balance. The identification of these mechanisms has great potential to identify novel targets for the treatment of diabetes and related metabolic disorders. Herein, we review the central role of the adipocyte in the maintenance of metabolic homeostasis, highlighting three critical mediators: adiponectin, leptin, and fatty acids.
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Affiliation(s)
- Jennifer H Stern
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Joseph M Rutkowski
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Philipp E Scherer
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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Sierra Rojas JX, García-San Frutos M, Horrillo D, Lauzurica N, Oliveros E, Carrascosa JM, Fernández-Agulló T, Ros M. Differential Development of Inflammation and Insulin Resistance in Different Adipose Tissue Depots Along Aging in Wistar Rats: Effects of Caloric Restriction. J Gerontol A Biol Sci Med Sci 2015; 71:310-22. [DOI: 10.1093/gerona/glv117] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 02/14/2015] [Indexed: 01/06/2023] Open
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Rodríguez M, Moltó E, Aguado L, Gallardo N, Andrés A, Arribas C. S-resistin, a non secretable resistin isoform, impairs the insulin signalling pathway in 3T3-L1 adipocytes. J Physiol Biochem 2015; 71:381-90. [PMID: 26036220 DOI: 10.1007/s13105-015-0418-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 05/26/2015] [Indexed: 01/14/2023]
Abstract
S-resistin is a non-secretable resistin spliced variant, which is expressed mainly in the white adipose tissue from Wistar rats. Previous results confirmed that 3T3-L1 cells expressing s-resistin (3T3-L1-s-res) showed an inflammatory response and exhibited a decrease in glucose transport, both basal and insulin-stimulated. Here we present evidences demonstrating for the first time that s-resistin, like resistin, blocks insulin signalling pathway by inhibiting insulin receptor, insulin receptor substrate 1, protein kinase B/Akt and the mammalian target of rapamycin phosphorylation, and increasing the suppressor of cytokine signalling 3 levels being the later probably due to augmented of leptin expression. Thus, our data suggest that s-resistin could act by a still unknown intracrine pathway as an intracellular sensor, regulating the adipocyte insulin sensitivity.
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Affiliation(s)
- María Rodríguez
- Área de Bioquímica. Facultad de Ciencias Ambientales y Bioquímica, Centro Regional de Investigaciones Biomédicas (CRIB), Universidad de Castilla-La Mancha, Av. Carlos III s/n, 45071, Toledo, Spain
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Wronska A, Lawniczak A, Wierzbicki PM, Goyke E, Sledzinski T, Kmiec Z. White Adipose Tissue Depot-Specific Activity of Lipogenic Enzymes in Response to Fasting and Refeeding in Young and Old Rats. Gerontology 2015; 61:448-55. [PMID: 25721559 DOI: 10.1159/000371578] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 12/16/2014] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Although the heterogeneity of white adipose tissue (WAT) in different anatomical sites is a well-known phenomenon, there are scarce data on aging-associated metabolic alterations in various WAT depots. OBJECTIVE We used the model of fasting and refeeding to analyze the effect of aging on the activity of key lipogenic enzymes in retroperitoneal (rWAT), epididymal (eWAT), and subcutaneous (sWAT) adipose tissue depots. METHODS 5- and 24-month-old male Wistar rats were fasted for 48 h or were fasted for 2 days and subsequently refed for 2 or 4 days. Control animals had ad libitum access to chow. Samples obtained from three WAT deposits were analyzed for the enzymatic activities of ATP citrate lyase (ACL), fatty acid synthase (FAS), and glucose-6-phosphate dehydrogenase (G6PD). Concentrations of lipids and proteins were measured in the blood serum. RESULTS Fasting for 2 days decreased the concentration of free fatty acids only in the young rats. The basal activities of ACL and FAS were lower in eWAT than in rWAT and sWAT of the young rats. In the young rats, fasting did not change ACL and FAS activities in any of the studied depots. Refeeding increased these activities more quickly in rWAT than in eWAT, while in sWAT no induction was observed. ACL and FAS activities were manifold lower in all WAT depots of the old than in those of the young rats. In the old animals fasting had no effect on ACL activity in any depot and decreased FAS activity only in sWAT. After 4 days of refeeding, FAS activity increased in rWAT and sWAT, but no change in ACL activity occurred. G6PD activity in the young rats was lower by 40% in eWAT than in rWAT. The induction of the enzyme by refeeding occurred faster in rWAT than in eWAT, while in sWAT no change in G6PD activity was observed. G6PD activity did not change with aging. Fasting of the old rats decreased G6PD activity in rWAT and sWAT. Refeeding failed to induce the enzyme in these depots, whereas in eWAT G6PD activity increased by 76% after 4 days of refeeding. CONCLUSION Fasting and refeeding revealed WAT depot-specific, age-related changes of the activities of lipogenic enzymes.
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Affiliation(s)
- Agata Wronska
- Department of Histology, Medical University of Gdansk, Gdansk, Poland
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25
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Granado M, Rubio C, Amor S, Monge L, Fernández N, Carreño-Tarragona G, Carrascosa JM, García-Villalón ÁL. Effects of age and caloric restriction on the cardiac and coronary response to endothelin-1 in rats. Exp Gerontol 2014; 60:183-9. [DOI: 10.1016/j.exger.2014.10.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Revised: 10/29/2014] [Accepted: 10/31/2014] [Indexed: 10/24/2022]
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Borer KT. Counterregulation of insulin by leptin as key component of autonomic regulation of body weight. World J Diabetes 2014; 5:606-629. [PMID: 25317239 PMCID: PMC4138585 DOI: 10.4239/wjd.v5.i5.606] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Revised: 05/15/2014] [Accepted: 06/03/2014] [Indexed: 02/05/2023] Open
Abstract
A re-examination of the mechanism controlling eating, locomotion, and metabolism prompts formulation of a new explanatory model containing five features: a coordinating joint role of the (1) autonomic nervous system (ANS); (2) the suprachiasmatic (SCN) master clock in counterbalancing parasympathetic digestive and absorptive functions and feeding with sympathetic locomotor and thermogenic energy expenditure within a circadian framework; (3) interaction of the ANS/SCN command with brain substrates of reward encompassing dopaminergic projections to ventral striatum and limbic and cortical forebrain. These drive the nonhomeostatic feeding and locomotor motivated behaviors in interaction with circulating ghrelin and lateral hypothalamic neurons signaling through melanin concentrating hormone and orexin-hypocretin peptides; (4) counterregulation of insulin by leptin of both gastric and adipose tissue origin through: potentiation by leptin of cholecystokinin-mediated satiation, inhibition of insulin secretion, suppression of insulin lipogenesis by leptin lipolysis, and modulation of peripheral tissue and brain sensitivity to insulin action. Thus weight-loss induced hypoleptimia raises insulin sensitivity and promotes its parasympathetic anabolic actions while obesity-induced hyperleptinemia supresses insulin lipogenic action; and (5) inhibition by leptin of bone mineral accrual suggesting that leptin may contribute to the maintenance of stability of skeletal, lean-body, as well as adipose tissue masses.
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Is bisphenol S a safe substitute for bisphenol A in terms of metabolic function? An in vitro study. Toxicol Appl Pharmacol 2014; 280:224-35. [PMID: 25111128 DOI: 10.1016/j.taap.2014.07.025] [Citation(s) in RCA: 127] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Revised: 07/29/2014] [Accepted: 07/31/2014] [Indexed: 01/08/2023]
Abstract
As bisphenol A (BPA) has been shown to induce adverse effects on human health, especially through the activation of endocrine pathways, it is about to be withdrawn from the European market and replaced by analogues such as bisphenol S (BPS). However, toxicological data on BPS is scarce, and so it is necessary to evaluate the possible effects of this compound on human health. We compared the effect of BPA and BPS on obesity and hepatic steatosis processes using low doses in the same range as those found in the environment. Two in vitro models were used, the adipose cell line 3T3-L1 and HepG2 cells, representative of hepatic functions. We analyzed different parameters such as lipid and glucose uptakes, lipolysis, leptin production and the modulation of genes involved in lipid metabolism and energy balance. BPA and BPS induced an increase in the lipid content in the 3T3-L1 cell line and more moderately in the hepatic cells. We also observed a decrease in lipolysis after bisphenol treatment of adipocytes, but only BPS was involved in the increase in glucose uptake and leptin production. These latter effects could be linked to the modulation of SREBP-1c, PPARγ, aP2 and ERRα and γ genes after exposure to BPA, whereas BPS seems to target the PGC1α and the ERRγ genes. The findings suggest that both BPA and BPS could be involved in obesity and steatosis processes, but through two different metabolic pathways.
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28
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Winkler G. [Is there any progress in the blood glucose lowering therapy of type 2 diabetes?]. Orv Hetil 2014; 155:1215-20. [PMID: 25095281 DOI: 10.1556/oh.2014.29979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Principles of glycemic treatment of type 2 diabetes are well outlined for a long time, however, emphasis of therapeutic strategies and treatment guidelines are continuously changing partially due to the continuous expansion of the available antihyperglycemic drugs. This article overviews the modifications of the drug selection arising from the broadening of the pathogenetic knowledge and recent therapeutic guidelines. It presents the role of the patient-centered approach in the therapeutic choice, highlights occasional contradictions between recent international and national guidelines and financing rules in Hungary. While consideration of the different antidiabetics by the same criteria and the choice of the most appropriate drug characterize international practice, prescription of certain compounds is often restricted by financial rules in Hungary.
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Affiliation(s)
- Gábor Winkler
- Szent János Kórház II. Belgyógyászat-Diabetológia Budapest Diós árok 1-3. 1125 Miskolci Egyetem, Egészségügyi Kar Elméleti Egészségtudományi Tanszék Miskolc
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Abstract
The fat‐derived hormone, leptin, is well known to regulate body weight. However, there is now substantial evidence that leptin also plays a primary role in the regulation of glucose homeostasis, independent of actions on food intake, energy expenditure or body weight. As such, leptin might have clinical utility in treating hyperglycemia, particularly in conditions of leptin deficiency, such as lipodystrophy and diabetes mellitus. The mechanisms through which leptin modulates glucose metabolism have not been fully elucidated. Leptin receptors are widely expressed in peripheral tissues, including the endocrine pancreas, liver, skeletal muscle and adipose, and both direct and indirect leptin action on these tissues contributes to the control of glucose homeostasis. Here we review the role of leptin in glucose homeostasis, along with our present understanding of the mechanisms involved. (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2012.00203.x, 2012)
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Affiliation(s)
- Heather C Denroche
- Department of Cellular and Physiological Sciences, The Life Sciences Institute
| | - Frank K Huynh
- Department of Cellular and Physiological Sciences, The Life Sciences Institute
| | - Timothy J Kieffer
- Department of Cellular and Physiological Sciences, The Life Sciences Institute ; Department of Surgery, University of British Columbia, Vancouver, British Columbia, Canada
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Gowdra VS, Mudgal J, Bansal P, Nayak PG, Manohara Reddy SA, Shenoy GG, Valiathan M, Chamallamudi MR, Nampurath GK. Synthesis, characterization, and preclinical evaluation of new thiazolidin-4-ones substituted with p-chlorophenoxy acetic acid and clofibric acid against insulin resistance and metabolic disorder. BIOMED RESEARCH INTERNATIONAL 2014; 2014:620434. [PMID: 24995315 PMCID: PMC4065710 DOI: 10.1155/2014/620434] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 05/03/2014] [Accepted: 05/06/2014] [Indexed: 11/18/2022]
Abstract
We synthesized twenty thiazolidin-4-one derivatives, which were then characterized by standard chromatographic and spectroscopic methods. From the in vitro glucose uptake assay, two compounds behaved as insulin sensitizers, where they enhanced glucose uptake in isolated rat diaphragm. In high-carbohydrate diet-induced insulin resistant mice, these two thiazolidin-4-ones attenuated hyperglycemia, hyperinsulinemia, hypertriglyceridemia, hypercholesterolemia, and glucose intolerance. They raised the plasma leptin but did not reverse the diabetes-induced hypoadiponectinemia. Additionally, compound 3a reduced adiposity. The test compounds were also able to reverse the disturbed liver antioxidant milieu. To conclude, these two novel thiazolidin-4-ones modulated multiple mechanisms involved in metabolic disorders, reversing insulin resistance and thus preventing the development of type-2 diabetes.
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Affiliation(s)
- Vasantharaju S. Gowdra
- Department of Pharmaceutical Quality Assurance, Manipal College of Pharmaceutical Sciences, Manipal University, Manipal, Karnataka 576104, India
| | - Jayesh Mudgal
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal University, Manipal, Karnataka 576104, India
| | - Punit Bansal
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal University, Manipal, Karnataka 576104, India
| | - Pawan G. Nayak
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal University, Manipal, Karnataka 576104, India
| | - Seethappa A. Manohara Reddy
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal University, Manipal, Karnataka 576104, India
| | - Gautham G. Shenoy
- Department of Pharmaceutical Chemistry, Manipal College of Pharmaceutical Sciences, Manipal University, Manipal, Karnataka 576104, India
| | - Manna Valiathan
- Department of Pathology, Kasturba Medical College, Manipal University, Manipal, Karnataka 576104, India
| | - Mallikarjuna R. Chamallamudi
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal University, Manipal, Karnataka 576104, India
| | - Gopalan K. Nampurath
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal University, Manipal, Karnataka 576104, India
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Liang X, Pei H, Ma L, Ran Y, Chen J, Wang G, Chen L. Synthesis and biological evaluation of novel urea- and guanidine-based derivatives for the treatment of obesity-related hepatic steatosis. Molecules 2014; 19:6163-83. [PMID: 24838072 PMCID: PMC6271706 DOI: 10.3390/molecules19056163] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Revised: 04/14/2014] [Accepted: 04/15/2014] [Indexed: 02/05/2023] Open
Abstract
Leptin, the product of the obese gene, is an adipocyte-secreted protein hormone playing a key role in the progression of obesity and hepatic steatosis. In this study, 28 novel (thio)urea and guanidine-based analogues have been synthesized and N-(1-(4-(3-(2-chloroethyl)ureido)benzyl)piperidin-4-yl)-3-(trifluoromethyl) benzamide (7i) was found to be a potent regulator of leptin expression in 3T3-L1 adipocytes. Treatment with 7i at a dose of 50 mg/kg/day for 35 days reduced the body weight and liver weight of diet-induced obesity mice by 13.5% and 18.4%, respectively, while also improving the serum levels of triglyceride, total cholesterol, leptin, adiponectin, LDL-c, HDL-c. Hematoxylin-eosin (H&E) and Oil Red O staining also confirmed that 7i ameliorated fat deposition in liver tissue and restricted the size of adipocytes in obesity-related fatty liver disease.
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Affiliation(s)
- Xiaolin Liang
- State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Keyuan Road 4, Gaopeng Street, Chengdu 610041, China.
| | - Heying Pei
- State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Keyuan Road 4, Gaopeng Street, Chengdu 610041, China.
| | - Liang Ma
- State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Keyuan Road 4, Gaopeng Street, Chengdu 610041, China.
| | - Yan Ran
- State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Keyuan Road 4, Gaopeng Street, Chengdu 610041, China.
| | - Jinying Chen
- State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Keyuan Road 4, Gaopeng Street, Chengdu 610041, China.
| | - Guangcheng Wang
- State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Keyuan Road 4, Gaopeng Street, Chengdu 610041, China.
| | - Lijuan Chen
- State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Keyuan Road 4, Gaopeng Street, Chengdu 610041, China.
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32
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Jung UJ, Choi MS. Obesity and its metabolic complications: the role of adipokines and the relationship between obesity, inflammation, insulin resistance, dyslipidemia and nonalcoholic fatty liver disease. Int J Mol Sci 2014; 15:6184-223. [PMID: 24733068 PMCID: PMC4013623 DOI: 10.3390/ijms15046184] [Citation(s) in RCA: 1211] [Impact Index Per Article: 121.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 03/27/2014] [Accepted: 04/01/2014] [Indexed: 02/06/2023] Open
Abstract
Accumulating evidence indicates that obesity is closely associated with an increased risk of metabolic diseases such as insulin resistance, type 2 diabetes, dyslipidemia and nonalcoholic fatty liver disease. Obesity results from an imbalance between food intake and energy expenditure, which leads to an excessive accumulation of adipose tissue. Adipose tissue is now recognized not only as a main site of storage of excess energy derived from food intake but also as an endocrine organ. The expansion of adipose tissue produces a number of bioactive substances, known as adipocytokines or adipokines, which trigger chronic low-grade inflammation and interact with a range of processes in many different organs. Although the precise mechanisms are still unclear, dysregulated production or secretion of these adipokines caused by excess adipose tissue and adipose tissue dysfunction can contribute to the development of obesity-related metabolic diseases. In this review, we focus on the role of several adipokines associated with obesity and the potential impact on obesity-related metabolic diseases. Multiple lines evidence provides valuable insights into the roles of adipokines in the development of obesity and its metabolic complications. Further research is still required to fully understand the mechanisms underlying the metabolic actions of a few newly identified adipokines.
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Affiliation(s)
- Un Ju Jung
- Center for Food and Nutritional Genomics Research, Kyungpook National University, 1370 Sankyuk Dong Puk-ku, Daegu 702-701, Korea.
| | - Myung-Sook Choi
- Center for Food and Nutritional Genomics Research, Kyungpook National University, 1370 Sankyuk Dong Puk-ku, Daegu 702-701, Korea.
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Azrad M, Gower BA, Hunter GR, Nagy TR. Racial differences in adiponectin and leptin in healthy premenopausal women. Endocrine 2013; 43:586-92. [PMID: 22983832 PMCID: PMC3541432 DOI: 10.1007/s12020-012-9797-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Accepted: 09/05/2012] [Indexed: 12/16/2022]
Abstract
The aim of this article is to longitudinally investigate racial differences in serum adiponectin and leptin in European-American (EA) and African-American (AA) women in the overweight and weight-reduced states. Sixty-two EA and 58 AA premenopausal women were weight reduced from body mass index (BMI) 27-30 kg/m(2) to BMI ≤ 24. Fasting serum adiponectin and leptin were determined; body composition and intra-abdominal adipose tissue (IAAT) were measured with dual-energy X-ray absorptiometry and computed tomography, respectively. In repeated-measure MANOVA, there was a significant race effect for IAAT and total fat mass; compared to AA women, EA women had higher IAAT and total fat mass (p < 0.0001 and p = 0.027, respectively). In the mixed-model for adiponectin that adjusted for IAAT, limb fat, and total fat, race was significantly associated with adiponectin (p = 0.046). AA women had significantly lower adjusted adiponectin compared to EA women at baseline [7.67 (6.85, 8.60) vs. 9.32 (8.34, 10.4) μg/ml, p < 0.05] and following weight loss [9.75 (8.70, 10.9) vs. 11.8 (10.6, 13.2) μg/ml, p < 0.05]. In a mixed-model for leptin that adjusted for insulin, estradiol, and fat mass, race was significantly associated with leptin (p < 0.0001). AA women had significantly higher adjusted leptin compared to EA women at baseline [24.7 (22.3, 27.4) vs. 19.9 (18.1, 21.8) ng/dl, p < 0.05] and following weight loss [11.7 (10.2, 13.3) vs. 8.48 (7.50, 9.57) ng/dl, p < 0.05]. Despite having a more favorable body fat distribution, AA women had lower adjusted adiponectin and higher leptin. Differences in body composition and fat distribution do not appear to be significant factors in explaining lower adiponectin and higher leptin in AA women.
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Affiliation(s)
- Maria Azrad
- Department of Nutrition Sciences, University of Alabama, Birmingham, AL 35294, USA.
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Harris RBS. Direct and indirect effects of leptin on adipocyte metabolism. Biochim Biophys Acta Mol Basis Dis 2013; 1842:414-23. [PMID: 23685313 DOI: 10.1016/j.bbadis.2013.05.009] [Citation(s) in RCA: 177] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Revised: 04/18/2013] [Accepted: 05/06/2013] [Indexed: 12/22/2022]
Abstract
Leptin is hypothesized to function as a negative feedback signal in the regulation of energy balance. It is produced primarily by adipose tissue and circulating concentrations correlate with the size of body fat stores. Administration of exogenous leptin to normal weight, leptin responsive animals inhibits food intake and reduces the size of body fat stores whereas mice that are deficient in either leptin or functional leptin receptors are hyperphagic and obese, consistent with a role for leptin in the control of body weight. This review discusses the effect of leptin on adipocyte metabolism. Because adipocytes express leptin receptors there is the potential for leptin to influence adipocyte metabolism directly. Adipocytes also are insulin responsive and receive sympathetic innervation, therefore leptin can also modify adipocyte metabolism indirectly. Studies published to date suggest that direct activation of adipocyte leptin receptors has little effect on cell metabolism in vivo, but that leptin modifies adipocyte sensitivity to insulin to inhibit lipid accumulation. In vivo administration of leptin leads to a suppression of lipogenesis, an increase in triglyceride hydrolysis and an increase in fatty acid and glucose oxidation. Activation of central leptin receptors also contributes to the development of a catabolic state in adipocytes, but this may vary between different fat depots. Leptin reduces the size of white fat depots by inhibiting cell proliferation both through induction of inhibitory circulating factors and by contributing to sympathetic tone which suppresses adipocyte proliferation. This article is part of a Special Issue entitled: Modulation of Adipose Tissue in Health and Disease.
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Affiliation(s)
- Ruth B S Harris
- Department of Physiology, Medical College of Georgia, Georgia Regents University, USA.
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Sakuma K, Yamaguchi A. Sarcopenic obesity and endocrinal adaptation with age. Int J Endocrinol 2013; 2013:204164. [PMID: 23690769 PMCID: PMC3639625 DOI: 10.1155/2013/204164] [Citation(s) in RCA: 114] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Accepted: 03/01/2013] [Indexed: 02/06/2023] Open
Abstract
In normal aging, changes in the body composition occur that result in a shift toward decreased muscle mass and increased fat mass. The loss of muscle mass that occurs with aging is termed sarcopenia and is an important cause of frailty, disability, and loss of independence in older adults. Age-related changes in the body composition as well as the increased prevalence of obesity determine a combination of excess weight and reduced muscle mass or strength, recently defined as sarcopenic obesity. Weight gain increases total/abdominal fat, which, in turn, elicits inflammation and fatty infiltration in muscle. Sarcopenic obesity appears to be linked with the upregulation of TNF-α, interleukin (IL)-6, leptin, and myostatin and the downregulation of adiponectin and IL-15. Multiple combined exercise and mild caloric restriction markedly attenuate the symptoms of sarcopenic obesity. Intriguingly, the inhibition of myostatin induced by gene manipulation or neutralizing antibody ameliorates sarcopenic obesity via increased skeletal muscle mass and improved glucose homeostasis. In this review, we describe the possible influence of endocrinal changes with age on sarcopenic obesity.
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Affiliation(s)
- Kunihiro Sakuma
- Research Center for Physical Fitness, Sports and Health, Toyohashi University of Technology, 1-1 Hibarigaoka, Tenpaku-cho, Toyohashi 441-8580, Japan
- *Kunihiro Sakuma:
| | - Akihiko Yamaguchi
- School of Dentistry, Health Sciences University of Hokkaido, Kanazawa, Ishikari-Tobetsu, Hokkaido 061-0293, Japan
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Shaker OG, Sadik NAH. Vaspin gene in rat adipose tissue: relation to obesity-induced insulin resistance. Mol Cell Biochem 2012; 373:229-39. [DOI: 10.1007/s11010-012-1494-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Accepted: 10/18/2012] [Indexed: 12/01/2022]
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Burgos-Ramos E, Canelles S, Perianes-Cachero A, Arilla-Ferreiro E, Argente J, Barrios V. Adipose tissue promotes a serum cytokine profile related to lower insulin sensitivity after chronic central leptin infusion. PLoS One 2012; 7:e46893. [PMID: 23056516 PMCID: PMC3462753 DOI: 10.1371/journal.pone.0046893] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Accepted: 09/10/2012] [Indexed: 12/13/2022] Open
Abstract
Obesity is an inflammatory state characterized by an augment in circulating inflammatory factors. Leptin may modulate the synthesis of these factors by white adipose tissue decreasing insulin sensitivity. We have examined the effect of chronic central administration of leptin on circulating levels of cytokines and the possible relationship with cytokine expression and protein content as well as with leptin and insulin signaling in subcutaneous and visceral adipose tissues. In addition, we analyzed the possible correlation between circulating levels of cytokines and peripheral insulin resistance. We studied 18 male Wistar rats divided into controls (C), those treated icv for 14 days with a daily dose of 12 μg of leptin (L) and a pair-fed group (PF) that received the same food amount consumed by the leptin group. Serum leptin and insulin were measured by ELISA, mRNA levels of interferon-γ (IFN-γ), interleukin-2 (IL-2), IL-4, IL-6, IL-10 and tumor necrosis factor-α (TNF-α) by real time PCR and serum and adipose tissue levels of these cytokines by multiplexed bead immunoassay. Serum leptin, IL-2, IL-4, IFN-γ and HOMA-IR were increased in L and TNF-α was decreased in PF and L. Serum leptin and IL-2 levels correlate positively with HOMA-IR index and negatively with serum glucose levels during an ip insulin tolerance test. In L, an increase in mRNA levels of IL-2 was found in both adipose depots and IFN-γ only in visceral tissue. Activation of leptin signaling was increased and insulin signaling decreased in subcutaneous fat of L. In conclusion, leptin mediates the production of inflammatory cytokines by adipose tissue independent of its effects on food intake, decreasing insulin sensitivity.
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Affiliation(s)
- Emma Burgos-Ramos
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa and Department of Pediatrics, Universidad Autónoma de Madrid, Madrid, Spain
- Centro de Investigación Biomédica en Red Fisiopatología de Obesidad y Nutrición, Instituto de Salud Carlos III, Madrid, Spain
| | - Sandra Canelles
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa and Department of Pediatrics, Universidad Autónoma de Madrid, Madrid, Spain
- Centro de Investigación Biomédica en Red Fisiopatología de Obesidad y Nutrición, Instituto de Salud Carlos III, Madrid, Spain
| | - Arancha Perianes-Cachero
- Grupo de Neurobioquímica, Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad de Alcalá, Alcalá de Henares, Spain
| | - Eduardo Arilla-Ferreiro
- Grupo de Neurobioquímica, Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad de Alcalá, Alcalá de Henares, Spain
| | - Jesús Argente
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa and Department of Pediatrics, Universidad Autónoma de Madrid, Madrid, Spain
- Centro de Investigación Biomédica en Red Fisiopatología de Obesidad y Nutrición, Instituto de Salud Carlos III, Madrid, Spain
| | - Vicente Barrios
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa and Department of Pediatrics, Universidad Autónoma de Madrid, Madrid, Spain
- Centro de Investigación Biomédica en Red Fisiopatología de Obesidad y Nutrición, Instituto de Salud Carlos III, Madrid, Spain
- * E-mail:
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Effect of pioglitazone on the fructose-induced abdominal adipose tissue dysfunction. PPAR Res 2012; 2012:259093. [PMID: 23091482 PMCID: PMC3469242 DOI: 10.1155/2012/259093] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Accepted: 08/23/2012] [Indexed: 12/31/2022] Open
Abstract
Aim. To test the potential role of PPARγ in the endocrine abdominal tissue dysfunction induced by feeding normal rats with a fructose rich diet (FRD) during three weeks. Methodology. Adult normal male rats received a standard commercial diet (CD) or FRD, (10% in drinking water) without or with pioglitazone (PIO) (i.p. 0.25 mg/Kg BW/day; CD-PIO and FRD-PIO). Thereafter, we measured circulating metabolic, endocrine, and oxidative stress (OS) markers, abdominal adipose tissue (AAT) mass, leptin (LEP) and plasminogen activator inhibitor-1 (PAI-1) tissue content/expression, and leptin release by isolated adipocytes incubated with different concentrations of insulin. Results. Plasma glucose, insulin, triglyceride, TBARS, LEP, and PAI-1 levels were higher in FRD rats; PIO coadministration fully prevented all these increments. AAT adipocytes from FRD rats were larger, secreted a higher amount of LEP, and displayed decreased sensitivity to insulin stimulation; these effects were significantly ameliorated by PIO. Whereas AAT LEP and PAI-1 (mRNA) concentrations increased significantly in FRD rats, those of insulin-receptor-substrate- (IRS-) 1 and IRS-2 were reduced. PIO coadministration prevented FRD effects on LEP, PAI-1, and IRS-2 (fully) and IRS-1 (partially) mRNAs in AAT. Conclusion. PPARγ would play a relevant role in the development of the FRD-induced metabolic-endocrine dysfunction.
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Marroquí L, Gonzalez A, Ñeco P, Caballero-Garrido E, Vieira E, Ripoll C, Nadal A, Quesada I. Role of leptin in the pancreatic β-cell: effects and signaling pathways. J Mol Endocrinol 2012; 49:R9-17. [PMID: 22448029 DOI: 10.1530/jme-12-0025] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Leptin plays an important role in the control of food intake, energy expenditure, metabolism, and body weight. This hormone also has a key function in the regulation of glucose homeostasis. Although leptin acts through central and peripheral mechanisms to modulate glucose metabolism, the pancreatic β-cell of the endocrine pancreas is a critical target of leptin actions. Leptin receptors are present in the β-cell, and their activation directly inhibits insulin secretion from these endocrine cells. The effects of leptin on insulin occur also in the long term, since this hormone inhibits insulin gene expression as well. Additionally, β-cell mass can be affected by leptin through changes in proliferation, apoptosis, or cell size. All these different functions in the β-cell are triggered by leptin as a result of the large diversity of signaling pathways that this hormone is able to activate in the endocrine pancreas. Therefore, leptin can participate in glucose homeostasis owing to different levels of modulation of the pancreatic β-cell population. Furthermore, it has been proposed that alterations in this level of regulation could contribute to the impairment of β-cell function in obesity states. In the present review, we will discuss all these issues with special emphasis on the effects and pathways of leptin signaling in the pancreatic β-cell.
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Affiliation(s)
- Laura Marroquí
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas-CIBERDEM, Elche, Spain
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40
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Involvement of protein tyrosine phosphatases and inflammation in hypothalamic insulin resistance associated with ageing: effect of caloric restriction. Mech Ageing Dev 2012; 133:489-97. [PMID: 22733037 DOI: 10.1016/j.mad.2012.06.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2012] [Revised: 05/17/2012] [Accepted: 06/04/2012] [Indexed: 12/13/2022]
Abstract
Aged Wistar rats present central insulin resistance associated with ageing. Several steps of the insulin signaling pathway have been described to be impaired in aged rats at hypothalamic level. In the present article we have explored possible alterations in protein tyrosine phosphatases (PTPs) involved in insulin receptor dephosphorylation, as well as pro-inflammatory pathways and serine kinases such as inhibitory kappa β kinase-nuclear factor kappa-B (IKKβ-NFκB), p38 mitogen-activated protein kinase (p38) and protein kinase C θ (PKCθ) that may also be involved in the decreased insulin signaling during ageing. We detected that ageing brings about a specific increase in insulin receptor tyrosine phosphatase activity and PTP1B serine phosphorylation. Increased association of PTP1B and leukocyte common antigen-related tyrosine protein phosphatase (LAR) with insulin receptor was also observed in hypothalamus from aged rats. Besides these mechanisms, increased activation of the IKKβ-NFκB pathway, p38 and PKCθ serine/threonine kinases were also detected. These data contribute to explain the hypothalamic insulin resistance associated with ageing. Caloric restriction ameliorates most of the effects of ageing on the above mentioned increases in PTPs and serine/threonine kinases activities and points to age-associated adiposity and inflammation as key factors in the development of age-associated insulin resistance.
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41
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High-fat diet feeding induces a depot-dependent response on the pro-inflammatory state and mitochondrial function of gonadal white adipose tissue. Br J Nutr 2012; 109:413-24. [DOI: 10.1017/s0007114512001171] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Obesity has been related to a chronic pro-inflammatory state affecting white adipose tissue (WAT), which has a great impact on carbohydrate, lipid and energy metabolism. In turn, the dysregulation of adipokine secretion derived from the accumulation of excess lipids in adipocytes further contributes to the development of insulin resistance and can be associated with mitochondrial dysfunction. The aim of the present study was to determine whether sexual dimorphism found in the systemic insulin sensitivity profile is related to sex differences in a high-fat diet (HFD) response of gonadal WAT at mitochondrial function and inflammatory profile levels. Wistar rats (10 weeks old) of both sexes were fed a control pelleted diet (3 % (w/w) fat;n8 for each sex) or a HFD (24 % (w/w) fat;n8 for each sex). Serum insulin sensitivity markers, mRNA expression levels of inflammatory factors and the protein content of insulin and adiponectin signalling pathways were analysed, as well as the levels of the main markers of mitochondrial biogenesis, antioxidant defence and oxidative damage. In the present study, the periovarian depot exhibits a greater expandability capacity, along with a lower hypoxic and pro-inflammatory state, without signs of mitochondrial dysfunction or changes in its dynamics. In contrast, epididymal fat has a much more pronounced pro-inflammatory, hypoxic and insulin-resistant profile accompanied by changes in mitochondrial dynamics, probably associated with HFD-induced mitochondrial dysfunction. Thus, this explains the worse serum insulin sensitivity profile of male rats.
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42
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De Solís AJ, Fernández-Agulló T, García-SanFrutos M, Pérez-Pardo P, Bogónez E, Andrés A, Ros M, Carrascosa JM. Impairment of skeletal muscle insulin action with aging in Wistar rats: Role of leptin and caloric restriction. Mech Ageing Dev 2012; 133:306-16. [DOI: 10.1016/j.mad.2012.03.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Revised: 02/13/2012] [Accepted: 03/06/2012] [Indexed: 01/04/2023]
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Owen C, Czopek A, Agouni A, Grant L, Judson R, Lees EK, Mcilroy GD, Göransson O, Welch A, Bence KK, Kahn BB, Neel BG, Mody N, Delibegović M. Adipocyte-specific protein tyrosine phosphatase 1B deletion increases lipogenesis, adipocyte cell size and is a minor regulator of glucose homeostasis. PLoS One 2012; 7:e32700. [PMID: 22389718 PMCID: PMC3289674 DOI: 10.1371/journal.pone.0032700] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Accepted: 01/30/2012] [Indexed: 12/16/2022] Open
Abstract
Protein tyrosine phosphatase 1B (PTP1B), a key negative regulator of leptin and insulin signaling, is positively correlated with adiposity and contributes to insulin resistance. Global PTP1B deletion improves diet-induced obesity and glucose homeostasis via enhanced leptin signaling in the brain and increased insulin signaling in liver and muscle. However, the role of PTP1B in adipocytes is unclear, with studies demonstrating beneficial, detrimental or no effect(s) of adipose-PTP1B-deficiency on body mass and insulin resistance. To definitively establish the role of adipocyte-PTP1B in body mass regulation and glucose homeostasis, adipocyte-specific-PTP1B knockout mice (adip-crePTP1B−/−) were generated using the adiponectin-promoter to drive Cre-recombinase expression. Chow-fed adip-crePTP1B−/− mice display enlarged adipocytes, despite having similar body weight/adiposity and glucose homeostasis compared to controls. High-fat diet (HFD)-fed adip-crePTP1B−/− mice display no differences in body weight/adiposity but exhibit larger adipocytes, increased circulating glucose and leptin levels, reduced leptin sensitivity and increased basal lipogenesis compared to controls. This is associated with decreased insulin receptor (IR) and Akt/PKB phosphorylation, increased lipogenic gene expression and increased hypoxia-induced factor-1-alpha (Hif-1α) expression. Adipocyte-specific PTP1B deletion does not beneficially manipulate signaling pathways regulating glucose homeostasis, lipid metabolism or adipokine secretion in adipocytes. Moreover, PTP1B does not appear to be the major negative regulator of the IR in adipocytes.
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Affiliation(s)
- Carl Owen
- Integrative Physiology, University of Aberdeen, Aberdeen, United Kingdom
| | - Alicja Czopek
- Integrative Physiology, University of Aberdeen, Aberdeen, United Kingdom
| | - Abdelali Agouni
- Integrative Physiology, University of Aberdeen, Aberdeen, United Kingdom
| | - Louise Grant
- Integrative Physiology, University of Aberdeen, Aberdeen, United Kingdom
| | - Robert Judson
- School of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Emma K. Lees
- Integrative Physiology, University of Aberdeen, Aberdeen, United Kingdom
| | - George D. Mcilroy
- Integrative Physiology, University of Aberdeen, Aberdeen, United Kingdom
| | - Olga Göransson
- Department of Experimental Medical Science, Protein Phosphorylation Unit, Lund University, Lund, Sweden
| | - Andy Welch
- School of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Kendra K. Bence
- Department of Animal Biology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, United States of America
| | - Barbara B. Kahn
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Centre, Boston, United States of America
| | - Benjamin G. Neel
- Campbell Family Cancer Research Institute, Ontario Cancer Institute, Princess Margaret Hospital, University of Toronto, Toronto, Canada
| | - Nimesh Mody
- Integrative Physiology, University of Aberdeen, Aberdeen, United Kingdom
| | - Mirela Delibegović
- Integrative Physiology, University of Aberdeen, Aberdeen, United Kingdom
- * E-mail:
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Quintas A, de Solís AJ, Díez-Guerra FJ, Carrascosa JM, Bogónez E. Age-associated decrease of SIRT1 expression in rat hippocampus. Exp Gerontol 2012; 47:198-201. [DOI: 10.1016/j.exger.2011.11.010] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2011] [Revised: 11/18/2011] [Accepted: 11/19/2011] [Indexed: 12/13/2022]
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45
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Ugleholdt R, Pedersen J, Bassi MR, Füchtbauer EM, Jørgensen SM, Kissow HL, Nytofte N, Poulsen SS, Rosenkilde MM, Seino Y, Thams P, Holst PJ, Holst JJ. Transgenic rescue of adipocyte glucose-dependent insulinotropic polypeptide receptor expression restores high fat diet-induced body weight gain. J Biol Chem 2011; 286:44632-45. [PMID: 22027838 DOI: 10.1074/jbc.m111.311779] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The glucose-dependent insulinotropic polypeptide receptor (GIPr) has been implicated in high fat diet-induced obesity and is proposed as an anti-obesity target despite an uncertainty regarding the mechanism of action. To independently investigate the contribution of the insulinotropic effects and the direct effects on adipose tissue, we generated transgenic mice with targeted expression of the human GIPr to white adipose tissue or beta-cells, respectively. These mice were then cross-bred with the GIPr knock-out strain. The central findings of the study are that mice with GIPr expression targeted to adipose tissue have a similar high fat diet -induced body weight gain as control mice, significantly greater than the weight gain in mice with a general ablation of the receptor. Surprisingly, this difference was due to an increase in total lean body mass rather than a gain in total fat mass that was similar between the groups. In contrast, glucose-dependent insulinotropic polypeptide-mediated insulin secretion does not seem to be important for regulation of body weight after high fat feeding. The study supports a role of the adipocyte GIPr in nutrient-dependent regulation of body weight and lean mass, but it does not support a direct and independent role for the adipocyte or beta-cell GIPr in promoting adipogenesis.
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Affiliation(s)
- Randi Ugleholdt
- Department of Biomedical Sciences, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
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Mantzoros CS, Magkos F, Brinkoetter M, Sienkiewicz E, Dardeno TA, Kim SY, Hamnvik OPR, Koniaris A. Leptin in human physiology and pathophysiology. Am J Physiol Endocrinol Metab 2011; 301:E567-84. [PMID: 21791620 PMCID: PMC3191548 DOI: 10.1152/ajpendo.00315.2011] [Citation(s) in RCA: 384] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Leptin, discovered through positional cloning 15 years ago, is an adipocyte-secreted hormone with pleiotropic effects in the physiology and pathophysiology of energy homeostasis, endocrinology, and metabolism. Studies in vitro and in animal models highlight the potential for leptin to regulate a number of physiological functions. Available evidence from human studies indicates that leptin has a mainly permissive role, with leptin administration being effective in states of leptin deficiency, less effective in states of leptin adequacy, and largely ineffective in states of leptin excess. Results from interventional studies in humans demonstrate that leptin administration in subjects with congenital complete leptin deficiency or subjects with partial leptin deficiency (subjects with lipoatrophy, congenital or related to HIV infection, and women with hypothalamic amenorrhea) reverses the energy homeostasis and neuroendocrine and metabolic abnormalities associated with these conditions. More specifically, in women with hypothalamic amenorrhea, leptin helps restore abnormalities in hypothalamic-pituitary-peripheral axes including the gonadal, thyroid, growth hormone, and to a lesser extent adrenal axes. Furthermore, leptin results in resumption of menses in the majority of these subjects and, in the long term, may increase bone mineral content and density, especially at the lumbar spine. In patients with congenital or HIV-related lipoatrophy, leptin treatment is also associated with improvements in insulin sensitivity and lipid profile, concomitant with reduced visceral and ectopic fat deposition. In contrast, leptin's effects are largely absent in the obese hyperleptinemic state, probably due to leptin resistance or tolerance. Hence, another emerging area of research pertains to the discovery and/or usefulness of leptin sensitizers. Results from ongoing studies are expected to further increase our understanding of the role of leptin and the potential clinical applications of leptin or its analogs in human therapeutics.
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Affiliation(s)
- Christos S Mantzoros
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
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47
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Horrillo D, Sierra J, Arribas C, García-San Frutos M, Carrascosa JM, Lauzurica N, Fernández-Agulló T, Ros M. Age-associated development of inflammation in Wistar rats: Effects of caloric restriction. Arch Physiol Biochem 2011; 117:140-50. [PMID: 21635187 DOI: 10.3109/13813455.2011.577435] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
CONTEXT Insulin resistance and type 2 Diabetes have been associated to a low grade of inflammation and their prevalence increase with ageing. OBJECTIVE To analyse the development of inflammation in adipose tissue, liver, muscle and hypothalamus during ageing and the effects of caloric restriction. MATERIALS AND METHODS We have analysed the expression of inflammatory cytokines (TNFα, IL1-β, IL-12B and IL-6), proteins involved in macrophage recruitment (MCP-1, CCR2), TLR4 and macrophage markers (CD11c, CD11b and arginase1). Immunohistochemistry of macrophages has also been performed. RESULTS All studied tissues present signs of inflammation during ageing, but with different pattern and intensity. Caloric restriction decreases the expression of most of inflammatory markers. DISCUSSION AND CONCLUSIONS These data indicate a role of adiposity in the development of inflammation and insulin resistance during ageing. Dietetic intervention could be a useful tool to ameliorate the development of inflammation and insulin resistance associated with ageing.
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Affiliation(s)
- Daniel Horrillo
- Facultad de Ciencias de la Salud, Universidad Rey Juan Carlos, Alcorcón, 28922, Madrid, Spain
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48
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Huml M, Kobr J, Siala K, Varvařovská J, Pomahačová R, Karlíková M, Sýkora J. Gut peptide hormones and pediatric type 1 diabetes mellitus. Physiol Res 2011; 60:647-58. [PMID: 21574763 DOI: 10.33549/physiolres.931995] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The aims of our study were to evaluate plasma levels of gut hormones in children with Type 1 diabetes mellitus (T1DM) in comparison with healthy controls and to correlate plasma concentrations of gut hormones with blood biochemistry, markers of metabolic control and with anthropometric parameters. We measured postprandial levels of specific gut peptide hormones in T1DM children. Amylin, glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide 1 (GLP-1), ghrelin, leptin, pancreatic polypeptide (PP), and polypeptide YY (PYY) were assessed in 19 T1DM children and 21 healthy reference controls. Multiplex assay kit (LINCOplex(®)) was used for determination of the defined plasma hormone levels. T1DM subjects had significantly reduced amylin (p<0.001) and ghrelin (p<0.05) levels, whereas GIP (p<0.05) was elevated when compared with healthy controls. Plasma levels of other measured hormones did not differ statistically between the studied groups. Further analysis of T1DM patients demonstrated an association between body mass index and GLP-1 (r=0.4642; p<0.05), leptin (r=0.5151; p<0.05), and amylin (r=0.5193; p<0.05). Ghrelin levels positively correlated with serum HDL cholesterol (r=0.4760; p<0.05). An inverse correlation was demonstrated with triglycerides (TG) (r= -0.5674; p<0.01), insulin dosage (r= -0.5366; p<0.05), and HbA1c% (r= -0.6864; p<0.01). Leptin was inversely correlated with TG (r= -0.6351; p<0.01). Stepwise regression analysis was performed to enlighten the predictive variables. Our study demonstrated an altered secretion pattern of gut peptide hormones in T1DM children. A close correlation was revealed between these peptides as well as with blood biochemistry, markers of metabolic control and with anthropometric parameters. Further studies are essential to explore this issue in T1DM children.
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Affiliation(s)
- M Huml
- Charles University in Prague, Faculty of Medicine in Pilsen, Faculty Hospital, Department of Pediatrics, Pilsen, Czech Republic.
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49
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Mittendorfer B, Horowitz JF, DePaoli AM, McCamish MA, Patterson BW, Klein S. Recombinant human leptin treatment does not improve insulin action in obese subjects with type 2 diabetes. Diabetes 2011; 60:1474-7. [PMID: 21411512 PMCID: PMC3292320 DOI: 10.2337/db10-1302] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
OBJECTIVE Leptin therapy improves insulin sensitivity in people with leptin deficiency, but it is not known whether it improves insulin action in people who are not leptin deficient. The purpose of the current study was to determine whether leptin treatment has weight loss-independent effects on insulin action in obese subjects with type 2 diabetes. RESEARCH DESIGN AND METHODS We conducted a randomized, placebo-controlled trial in obese subjects (BMI: 35.4 ± 0.6 kg/m(2); mean ± SE) with newly diagnosed type 2 diabetes. Subjects were randomized to treatment with placebo (saline), low-dose (30 mg/day), or high-dose (80 mg/day) recombinant methionyl human (r-Met hu) leptin for 14 days. Multiorgan insulin sensitivity before and after treatment was evaluated by using the hyperinsulinemic-euglycemic clamp procedure in conjunction with stable isotopically labeled tracer infusions to measure glucose, glycerol, and fatty acid kinetics. RESULTS Low-dose and high-dose leptin treatment resulted in a threefold (P < 0.01) and 150-fold (P < 0.001) increase in basal plasma leptin concentrations, respectively. However, neither low-dose nor high-dose therapy had an effect on insulin-mediated suppression of glucose, glycerol, or palmitate rates of appearance into plasma compared with placebo. In addition, leptin treatment did not increase insulin-mediated stimulation of glucose disposal compared with placebo (14.3 ± 3.1, 18.4 ± 3.6, 16.7 ± 2.4 vs. 17.5 ± 2.5, 20.7 ± 3.0, 19.1 ± 3.3 μmol/kg body wt/min before vs. after treatment in the placebo, low-dose, and high-dose leptin groups, respectively). CONCLUSIONS r-Met hu leptin does not have weight loss-independent, clinically important effects on insulin sensitivity in obese people with type 2 diabetes.
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Affiliation(s)
- Bettina Mittendorfer
- Center for Human Nutrition and Atkins Center of Excellence in Obesity Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Jeffrey F. Horowitz
- Center for Human Nutrition and Atkins Center of Excellence in Obesity Medicine, Washington University School of Medicine, St. Louis, Missouri
| | | | | | - Bruce W. Patterson
- Center for Human Nutrition and Atkins Center of Excellence in Obesity Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Samuel Klein
- Center for Human Nutrition and Atkins Center of Excellence in Obesity Medicine, Washington University School of Medicine, St. Louis, Missouri
- Corresponding author: Samuel Klein,
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50
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Bonzón-Kulichenko E, Fernández-Agulló T, Moltó E, Serrano R, Fernández A, Ros M, Carrascosa JM, Arribas C, Martínez C, Andrés A, Gallardo N. Regulation of insulin-stimulated glucose uptake in rat white adipose tissue upon chronic central leptin infusion: effects on adiposity. Endocrinology 2011; 152:1366-77. [PMID: 21285320 DOI: 10.1210/en.2010-0858] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Leptin enhances the glucose utilization in most insulin target tissues and paradoxically decreases it in white adipose tissue (WAT), but knowledge of the mechanisms underlying the inhibitory effect of central leptin on the insulin-dependent glucose uptake in WAT is limited. After 7 d intracerebroventricular leptin treatment (0.2 μg/d) of rats, the overall insulin sensitivity and the responsiveness of WAT after acute in vivo insulin administration were analyzed. We also performed unilateral WAT denervation to clarify the role of the autonomic nervous system in leptin effects on the insulin-stimulated [(3)H]-2-deoxyglucose transport in WAT. Central leptin improved the overall insulin sensitivity but decreased the in vivo insulin action in WAT, including insulin receptor autophosphorylation, insulin receptor substrate-1 tyrosine-phosphorylation, and Akt activation. In this tissue, insulin receptor substrate-1 and glucose transporter 4 mRNA and protein levels were down-regulated after central leptin treatment. Additionally, a remarkable up-regulation of resistin, together with an augmented expression of suppressor of cytokine signaling 3 in WAT, was also observed in leptin-treated rats. As a result, the insulin-stimulated glucose transporter 4 insertion at the plasma membrane and the glucose uptake in WAT were impaired in leptin-treated rats. Finally, denervation of WAT abolished the inhibitory effect of central leptin on glucose transport and decreased suppressor of cytokine signaling 3 and resistin levels in this tissue, suggesting that resistin, in an autocrine/paracrine manner, might be a mediator of central leptin antagonism of insulin action in WAT. We conclude that central leptin, inhibiting the insulin-stimulated glucose uptake in WAT, may regulate glucose availability for triacylglyceride formation and accumulation in this tissue, thereby contributing to the control of adiposity.
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Affiliation(s)
- Elena Bonzón-Kulichenko
- Area de Bioquímica, Facultad de Químicas, Regional Centre for Biomedical Research, Universidad de Castilla-La Mancha, 13071 Ciudad Real, Spain
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