51
|
Göbl CS, Ott J, Bozkurt L, Feichtinger M, Rehmann V, Cserjan A, Heinisch M, Steinbrecher H, JustKukurova I, Tuskova R, Leutner M, Vytiska-Binstorfer E, Kurz C, Weghofer A, Tura A, Egarter C, Kautzky-Willer A. To Assess the Association between Glucose Metabolism and Ectopic Lipid Content in Different Clinical Classifications of PCOS. PLoS One 2016; 11:e0160571. [PMID: 27505055 PMCID: PMC4978496 DOI: 10.1371/journal.pone.0160571] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 07/21/2016] [Indexed: 11/18/2022] Open
Abstract
Aims There are emerging data indicating an association between PCOS (polycystic ovary syndrome) and metabolic derangements with potential impact on its clinical presentation. This study aims to evaluate the pathophysiological processes beyond PCOS with particular focus on carbohydrate metabolism, ectopic lipids and their possible interaction. Differences between the two established classifications of the disease should be additionally evaluated. Methods A metabolic characterization was performed in 53 untreated PCOS patients as well as 20 controls including an extended oral glucose tolerance test (OGTT, to assess insulin sensitivity, secretion and ß-cell function) in addition to a detailed examination of ectopic lipid content in muscle and liver by nuclear magnetic resonance spectroscopy. Results Women with PCOS classified by the original NIH 1990 definition showed a more adverse metabolic risk profile compared to women characterized by the additional Rotterdam 2003 phenotypes. Subtle metabolic derangements were observed in both subgroups, including altered shapes of OGTT curves, impaired insulin action and hyperinsulinemia due to increased secretion and attenuated hepatic extraction. No differences were observed for ectopic lipids between the groups. However, particularly hepatocellular lipid content was significantly related to clinical parameters of PCOS like whole body insulin sensitivity, dyslipidemia and free androgen index. Conclusions Subtle alterations in carbohydrate metabolism are present in both PCOS classifications, but more profound in subjects meeting the NIH 1990 criteria. Females with PCOS and controls did not differ in ectopic lipids, however, liver fat was tightly related to hyperandrogenism and an adverse metabolic risk profile.
Collapse
Affiliation(s)
- Christian S. Göbl
- Department of Obstetrics and Gynecology, Division of Gynecologic Endocrinology and Reproductive Medicine, Medical University of Vienna, Vienna, Austria
| | - Johannes Ott
- Department of Obstetrics and Gynecology, Division of Gynecologic Endocrinology and Reproductive Medicine, Medical University of Vienna, Vienna, Austria
| | - Latife Bozkurt
- Department of Internal Medicine III, Division of Endocrinology and Metabolism, Unit of Gender Medicine, Medical University of Vienna, Vienna, Austria
| | - Michael Feichtinger
- Department of Obstetrics and Gynecology, Division of Gynecologic Endocrinology and Reproductive Medicine, Medical University of Vienna, Vienna, Austria
| | - Victoria Rehmann
- Department of Obstetrics and Gynecology, Division of Gynecologic Endocrinology and Reproductive Medicine, Medical University of Vienna, Vienna, Austria
| | - Anna Cserjan
- Department of Obstetrics and Gynecology, Division of Gynecologic Endocrinology and Reproductive Medicine, Medical University of Vienna, Vienna, Austria
| | - Maike Heinisch
- Department of Obstetrics and Gynecology, Division of Gynecologic Endocrinology and Reproductive Medicine, Medical University of Vienna, Vienna, Austria
| | - Helmut Steinbrecher
- Department of Obstetrics and Gynecology, Division of Gynecologic Endocrinology and Reproductive Medicine, Medical University of Vienna, Vienna, Austria
| | - Ivica JustKukurova
- High Field Magnetic Resonance Centre of Excellence, Medical University of Vienna, Vienna, Austria
| | - Radka Tuskova
- High Field Magnetic Resonance Centre of Excellence, Medical University of Vienna, Vienna, Austria
| | - Michael Leutner
- Department of Internal Medicine III, Division of Endocrinology and Metabolism, Unit of Gender Medicine, Medical University of Vienna, Vienna, Austria
| | - Elisabeth Vytiska-Binstorfer
- Department of Obstetrics and Gynecology, Division of Gynecologic Endocrinology and Reproductive Medicine, Medical University of Vienna, Vienna, Austria
| | - Christine Kurz
- Department of Obstetrics and Gynecology, Division of Gynecologic Endocrinology and Reproductive Medicine, Medical University of Vienna, Vienna, Austria
| | - Andrea Weghofer
- Department of Obstetrics and Gynecology, Division of Gynecologic Endocrinology and Reproductive Medicine, Medical University of Vienna, Vienna, Austria
| | - Andrea Tura
- Metabolic Unit, Institute of Neuroscience, National Research Council, Padova, Italy
| | - Christian Egarter
- Department of Obstetrics and Gynecology, Division of Gynecologic Endocrinology and Reproductive Medicine, Medical University of Vienna, Vienna, Austria
| | - Alexandra Kautzky-Willer
- Department of Internal Medicine III, Division of Endocrinology and Metabolism, Unit of Gender Medicine, Medical University of Vienna, Vienna, Austria
- * E-mail:
| |
Collapse
|
52
|
Abstract
Despite the importance of insulin signaling pathways in human disease, initial concerns that insect physiology and sugar metabolism differ enough from humans that flies would not model human disease hampered research in this area. However, during the past 10-15 years, evidence has accumulated that flies can indeed model various aspects of diabetes and related human disorders. This cluster of diseases impact insulin and insulin signaling pathways, fields which have been discussed in many excellent review articles in recent years. In this chapter, we restrict our focus to specific examples of diabetes-related disease models in Drosophila, discussing the advantages and limitations of these models in light of physiological similarities and differences between insects and mammals. We discuss features of metabolism and sugar regulation that are shared between flies and mammals, and specific Drosophila models for Type 1 and Type 2 diabetes, Metabolic syndrome, and related abnormalities including insulin resistance and heart disease. We conclude that fly models for diabetes and related disorders enhance our ability to identify genes and discern functional interactions that can be exploited for disease intervention.
Collapse
Affiliation(s)
- P Graham
- University of Maryland, College Park, MD, United States
| | - L Pick
- University of Maryland, College Park, MD, United States.
| |
Collapse
|
53
|
Men J, Huang Y, Solanki J, Zeng X, Alex A, Jerwick J, Zhang Z, Tanzi RE, Li A, Zhou C. Optical Coherence Tomography for Brain Imaging and Developmental Biology. IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS : A PUBLICATION OF THE IEEE LASERS AND ELECTRO-OPTICS SOCIETY 2016; 22:6803213. [PMID: 27721647 PMCID: PMC5049888 DOI: 10.1109/jstqe.2015.2513667] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Optical coherence tomography (OCT) is a promising research tool for brain imaging and developmental biology. Serving as a three-dimensional optical biopsy technique, OCT provides volumetric reconstruction of brain tissues and embryonic structures with micrometer resolution and video rate imaging speed. Functional OCT enables label-free monitoring of hemodynamic and metabolic changes in the brain in vitro and in vivo in animal models. Due to its non-invasiveness nature, OCT enables longitudinal imaging of developing specimens in vivo without potential damage from surgical operation, tissue fixation and processing, and staining with exogenous contrast agents. In this paper, various OCT applications in brain imaging and developmental biology are reviewed, with a particular focus on imaging heart development. In addition, we report findings on the effects of a circadian gene (Clock) and high-fat-diet on heart development in Drosophila melanogaster. These findings contribute to our understanding of the fundamental mechanisms connecting circadian genes and obesity to heart development and cardiac diseases.
Collapse
Affiliation(s)
- Jing Men
- Department of Electrical and Computer Engineering, Center for Photonics and Nanoelectronics, and Bioengineering Program, Lehigh University, Bethlehem, PA, USA, 18015
| | - Yongyang Huang
- Department of Electrical and Computer Engineering, Center for Photonics and Nanoelectronics, and Bioengineering Program, Lehigh University, Bethlehem, PA, USA, 18015
| | - Jitendra Solanki
- Department of Electrical and Computer Engineering, Center for Photonics and Nanoelectronics, and Bioengineering Program, Lehigh University, Bethlehem, PA, USA, 18015
| | - Xianxu Zeng
- Department of Electrical and Computer Engineering, Center for Photonics and Nanoelectronics, and Bioengineering Program, Lehigh University, Bethlehem, PA, USA, 18015
- Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, P.R. China, 450000
| | - Aneesh Alex
- Department of Electrical and Computer Engineering, Center for Photonics and Nanoelectronics, and Bioengineering Program, Lehigh University, Bethlehem, PA, USA, 18015
| | - Jason Jerwick
- Department of Electrical and Computer Engineering, Center for Photonics and Nanoelectronics, and Bioengineering Program, Lehigh University, Bethlehem, PA, USA, 18015
| | - Zhan Zhang
- Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, P.R. China, 450000
| | - Rudolph E. Tanzi
- Genetics and Aging Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA, 02129
| | - Airong Li
- Genetics and Aging Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA, 02129
| | - Chao Zhou
- Department of Electrical and Computer Engineering, Center for Photonics and Nanoelectronics, and Bioengineering Program, Lehigh University, Bethlehem, PA, USA, 18015
| |
Collapse
|
54
|
Robles PG, Sussman MS, Naraghi A, Brooks D, Goldstein RS, White LM, Mathur S. Intramuscular Fat Infiltration Contributes to Impaired Muscle Function in COPD. Med Sci Sports Exerc 2016; 47:1334-41. [PMID: 25373483 DOI: 10.1249/mss.0000000000000556] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
UNLABELLED Muscle weakness is a prevalent complication in chronic obstructive pulmonary disease (COPD). Atrophy does not fully explain muscle weakness in this population. The recent focus on fat infiltration and its clinical implications in age and diseased muscles are important because it may further explain the extent of declining muscle strength and mobility seen in COPD. PURPOSE The objectives of this study are to quantify fat infiltration (muscle quality) of lower-limb muscles in people with COPD and healthy older adults using magnetic resonance imaging and proton magnetic resonance spectroscopy, and to explore its relationship with muscle strength and walking capacity in COPD. METHODS T1-weighted magnetic resonance imaging and proton magnetic resonance spectroscopy were performed in people with COPD (n = 10) and control subjects (n = 10) matched for age, gender, and body mass index. Maximal cross-sectional area (muscle size), isokinetic and isometric muscle peak torques, and 6-min walk distance were also assessed. RESULTS In addition to muscle atrophy (mean between-group differences of 20% to 25%, P < 0.05), COPD group presented with fatty infiltration in thigh and calf muscles that were significantly greater than what was observed in their healthy counterparts (mean between-group differences of 74% to 89%, P = 0.001). There was a strong inverse correlation between intramuscular fat infiltration, muscle peak torque, and walking distance (r = -0.6 to -0.8, P < 0.001) in this group as opposed to fair-to-moderate correlations between muscle size and the same outcomes (r = 0.4-0.6, P < 0.01). CONCLUSION Poor muscle quality accompanies atrophy in people with COPD. Intramuscular fat infiltration not only appears to have a strong correlation with impaired function but also is more profound than muscle atrophy in this group. Monitoring both muscle size and quality may enable a more comprehensive assessment of exercise programs in COPD.
Collapse
Affiliation(s)
- Priscila Games Robles
- 1Graduate Department of Rehabilitation Sciences, University of Toronto, Toronto, Ontario, CANADA; 2Joint Department of Medical Imaging, University Health Network and Mount Sinai Hospital, University of Toronto, Toronto, Ontario, CANADA; 3Department of Physical Therapy, University of Toronto, Toronto, Ontario, CANADA; and 4Respiratory Medicine, West Park Healthcare Centre, Toronto, Ontario, CANADA
| | | | | | | | | | | | | |
Collapse
|
55
|
Daemen S, van Zandvoort MAMJ, Parekh SH, Hesselink MKC. Microscopy tools for the investigation of intracellular lipid storage and dynamics. Mol Metab 2015; 5:153-163. [PMID: 26977387 PMCID: PMC4770264 DOI: 10.1016/j.molmet.2015.12.005] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 12/19/2015] [Accepted: 12/27/2015] [Indexed: 12/01/2022] Open
Abstract
Background Excess storage of lipids in ectopic tissues, such as skeletal muscle, liver, and heart, seems to associate closely with metabolic abnormalities and cardiac disease. Intracellular lipid storage occurs in lipid droplets, which have gained attention as active organelles in cellular metabolism. Recent developments in high-resolution microscopy and microscopic spectroscopy have opened up new avenues to examine the physiology and biochemistry of intracellular lipids. Scope of review The aim of this review is to give an overview of recent technical advances in microscopy, and its application for the visualization, identification, and quantification of intracellular lipids, with special focus to lipid droplets. In addition, we attempt to summarize the probes currently available for the visualization of lipids. Major conclusions The continuous development of lipid probes in combination with the rapid development of microscopic techniques can provide new insights in the role and dynamics of intracellular lipids. Moreover, in situ identification of intracellular lipids is now possible and promises to add a new dimensionality to analysis of lipid biochemistry, and its relation to (patho)physiology.
Collapse
Key Words
- BODIPY, Boron-dipyrromethene
- CARS, coherent anti-stokes Raman scattering
- CLEM, correlative light electron microscopy
- CLSM, confocal laser scanning microscopy
- DIC, differential interference microscopy
- FA, fatty acid
- FIB-SEM, focused ion beam scanning electron microscopy
- FLIP, fluorescence loss in photobleaching
- FRAP, fluorescent recovery after photobleaching
- FRET, fluorescence resonance energy transfer
- Fluorescent lipid probes
- GFP, green fluorescent protein
- HCV, hepatitis C virus
- LD, lipid droplet
- Lipid droplets
- Live-cell imaging
- Metabolic disease
- NBD, nitro-benzoxadiazolyl
- PALM, photoactivation localization microscopy
- SBEM, serial block face scanning electron microscopy
- SIMS, Secondary Ion Mass Spectrometry
- SRS, Stimulated Raman Scattering
- STED, stimulated emission depletion
- STORM, stochastic optical reconstruction microscopy
- Super-resolution
- TAG, triacylglycerol
- TEM, transmission electron microscopy
- TOF-SIMS, time-of-flight SIMS
- TPLSM, two-photon laser scanning microscopy
- Vibrational microscopy
Collapse
Affiliation(s)
- Sabine Daemen
- Department of Human Movement Sciences and Human Biology, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University, Maastricht, The Netherlands.
| | - Marc A M J van Zandvoort
- Department of Genetics and Molecular Cell Biology, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands; Institute for Molecular Cardiovascular Research (IMCAR), RWTH Aachen University, Aachen, Germany.
| | - Sapun H Parekh
- Department of Molecular Spectroscopy, Max Planck Institute for Polymer Research, Mainz, Germany.
| | - Matthijs K C Hesselink
- Department of Human Movement Sciences and Human Biology, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University, Maastricht, The Netherlands.
| |
Collapse
|
56
|
Heymsfield SB, Hu HH, Shen W, Carmichael O. Emerging Technologies and their Applications in Lipid Compartment Measurement. Trends Endocrinol Metab 2015; 26:688-698. [PMID: 26596676 PMCID: PMC4673021 DOI: 10.1016/j.tem.2015.10.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Revised: 10/19/2015] [Accepted: 10/19/2015] [Indexed: 12/22/2022]
Abstract
Non-Communicable diseases (NCDs), including obesity, are emerging as the major health concern of the 21st century. Excess adiposity and related NCD metabolic disturbances have stimulated development of new lipid compartment measurement technologies to help us to understand cellular energy exchange, to refine phenotypes, and to develop predictive markers of adverse clinical outcomes. Recent advances now allow quantification of multiple intracellular lipid and adipose tissue compartments that can be evaluated across the human lifespan. With magnetic resonance methods leading the way, newer approaches will give molecular structural and metabolic information beyond the laboratory in real-world settings. The union between these new technologies and the growing NCD population is creating an exciting interface in advancing our understanding of chronic disease mechanisms.
Collapse
Affiliation(s)
- Steven B Heymsfield
- Pennington Biomedical Research Center, Louisiana State University (LSU) System, 6400 Perkins Road, Baton Rouge, LA 70808, USA.
| | - Houchun Harry Hu
- Phoenix Children's Hospital, Department of Radiology, 1919 East Thomas Road, Phoenix, AZ 85016, USA
| | - Wei Shen
- New York Obesity Research Center, Department of Pediatrics and Institute of Human Nutrition, Columbia University, New York, NY 10032, USA
| | - Owen Carmichael
- Pennington Biomedical Research Center, Louisiana State University (LSU) System, 6400 Perkins Road, Baton Rouge, LA 70808, USA
| |
Collapse
|
57
|
Liu TW, Heden TD, Matthew Morris E, Fritsche KL, Vieira-Potter VJ, Thyfault JP. High-Fat Diet Alters Serum Fatty Acid Profiles in Obesity Prone Rats: Implications for In Vitro Studies. Lipids 2015; 50:997-1008. [PMID: 26318121 DOI: 10.1007/s11745-015-4061-5] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Accepted: 08/10/2015] [Indexed: 12/27/2022]
Abstract
High-fat diets (HFD) are commonly used in rodents to induce obesity, increase serum fatty acids and induce lipotoxicity in various organs. In vitro studies commonly utilize individual free fatty acids (FFA) to study lipid exposure in an effort to model what is occurring in vivo; however, these approaches are not physiological as tissues are exposed to multiple fatty acids in vivo. Here we characterize circulating lipids in obesity-prone rats fed an HFD in both fasted and fed states with the goal of developing physiologically relevant fatty acid mixtures for subsequent in vitro studies. Rats were fed an HFD (60% kcal fat) or a control diet (10% kcal fat) for 3 weeks; liver tissue and both portal and systemic blood were collected. Fatty acid profiles and absolute concentrations of triglycerides (TAG) and FFA in the serum and TAG, diacylglycerol (DAG) and phospholipids in the liver were measured. Surprisingly, both systemic and portal serum TAG were ~40% lower in HFD-fed compared to controls. Overall, compared to the control diet, HFD feeding consistently induced an increase in the proportion of circulating polyunsaturated fatty acids (PUFA) with a concomitant decline in monounsaturated fatty acids (MUFA) and saturated fatty acids (SFA) in both serum TAG and FFA. The elevations of PUFA were mostly attributed to increases in n-6 PUFA, linoleic acid and arachidonic acid. In conclusion, fatty acid mixtures enriched with linoleic and arachidonic acid in addition to SFA and MUFA should be utilized for in vitro studies attempting to model lipid exposures that occur during in vivo HFD conditions.
Collapse
Affiliation(s)
- Tzu-Wen Liu
- Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, 65211, USA. .,Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
| | - Timothy D Heden
- Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, 65211, USA. .,Department of Kinesiology, East Carolina University, Greenville, NC, 27843, USA.
| | - E Matthew Morris
- Molecular and Integrative Physiology, University of Kansas Medical Center, 2067 Hemenway Life Sciences and Innovation Center, MS: 3043, 3901 Rainbow Blvd, Kansas, KS, 66160, USA.
| | - Kevin L Fritsche
- Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, 65211, USA. .,Animal Sciences, University of Missouri, Columbia, MO, 65211, USA.
| | | | - John P Thyfault
- Molecular and Integrative Physiology, University of Kansas Medical Center, 2067 Hemenway Life Sciences and Innovation Center, MS: 3043, 3901 Rainbow Blvd, Kansas, KS, 66160, USA. .,Research Service, Kansas City VA Medical Center, Kansas, MO, 64128, USA.
| |
Collapse
|
58
|
Tappy L, Schwarz JM. Metabolic Disorders. Clin Nutr 2015. [DOI: 10.1002/9781119211945.ch6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
59
|
Ritter O, Jelenik T, Roden M. Lipid-mediated muscle insulin resistance: different fat, different pathways? J Mol Med (Berl) 2015; 93:831-43. [PMID: 26108617 DOI: 10.1007/s00109-015-1310-2] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 05/27/2015] [Accepted: 06/12/2015] [Indexed: 12/22/2022]
Abstract
Increased dietary fat intake and lipolysis result in excessive lipid availability, which relates to impaired insulin sensitivity. Over the last years, several mechanisms possibly underlying lipid-mediated insulin resistance evolved. Lipid intermediates such as diacylglycerols (DAG) associate with changes in insulin sensitivity in many models. DAG activate novel protein kinase C (PKC) isoforms followed by inhibitory serine phosphorylation of insulin receptor substrate 1 (IRS1). Activation of Toll-like receptor 4 (TLR4) raises another lipid class, ceramides (CER), which induce pro-inflammatory pathways and lead to inhibition of Akt phosphorylation. Inhibition of glucosylceramide and ganglioside synthesis results in improved insulin sensitivity and increased activatory tyrosine phosphorylation of IRS1 in the muscle. Incomplete fat oxidation can increase acylcarnitines (ACC), which in turn stimulate pro-inflammatory pathways. This review analyzed the effects of lipid metabolites on insulin action in skeletal muscle of humans and rodents. Despite the evidence for the association of both DAG and CER with insulin resistance, its causal relevance may differ depending on the subcellular localization and the tested cohorts, e.g., athletes. Nevertheless, recent data indicate that individual lipid species and their degree of fatty acid saturation, particularly membrane and cytosolic C18:2 DAG, specifically activate PKCθ and induce both acute lipid-induced and chronic insulin resistance in humans.
Collapse
Affiliation(s)
- Olesja Ritter
- Institute for Clinical Diabetology, German Diabetes Center, c/o Auf'm Hennekamp 65, D-40225, Düsseldorf, Germany
| | | | | |
Collapse
|
60
|
Pang J, Cui J, Gong H, Xi C, Zhang TM. Effect of NAD on PARP-mediated insulin sensitivity in oleic acid treated hepatocytes. J Cell Physiol 2015; 230:1607-13. [PMID: 25536389 DOI: 10.1002/jcp.24907] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 12/18/2014] [Indexed: 12/23/2022]
Abstract
High serum free fatty acids levels are associated with the development of insulin resistance in type 2 diabetes; however, the precise mechanisms underlying this lipid toxicity are unclear. To investigate whether PARP1 activation and NAD depletion are involved in the impairment of insulin sensitivity associated with lipotoxicity, HepG2 cells were cultured with 500 μM oleic acid for 48 h. Oleic acid-treated cells exhibited increased ROS generation, lipid accumulation and PARP1 activation. Treatment with the PARP1 inhibitor PJ34 and transfection with PARP1 small interfering RNA both prevented the oleic acid-induced impairment of the insulin signaling pathway. Furthermore, treatment with PJ34 reversed the oleic acid-induced decrease in intracellular NAD concentration, while exogenous NAD protected cells against oleic acid-induced insulin insensitivity. Combined NAD and PJ34 administration did not enhance the effects obtained by treatment with either NAD or PJ34 alone. Interestingly, when cells were treated with the SIRT1 inhibitor EX527, the protective effects of PJ34 and NAD treatment were diminished. Taken together, these data suggest that NAD depletion by PARP1 activation is essential for the modulation of insulin sensitivity in oleic acid-induced lipotoxicity.
Collapse
Affiliation(s)
- Jing Pang
- The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics, Ministry of Health, China
| | | | | | | | | |
Collapse
|
61
|
Gancheva S, Koliaki C, Bierwagen A, Nowotny P, Heni M, Fritsche A, Häring HU, Szendroedi J, Roden M. Effects of intranasal insulin on hepatic fat accumulation and energy metabolism in humans. Diabetes 2015; 64:1966-75. [PMID: 25576060 DOI: 10.2337/db14-0892] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 01/07/2015] [Indexed: 11/13/2022]
Abstract
Studies in rodents suggest that insulin controls hepatic glucose metabolism through brain-liver crosstalk, but human studies using intranasal insulin to mimic central insulin delivery have provided conflicting results. In this randomized controlled crossover trial, we investigated the effects of intranasal insulin on hepatic insulin sensitivity (HIS) and energy metabolism in 10 patients with type 2 diabetes and 10 lean healthy participants (CON). Endogenous glucose production was monitored with [6,6-(2)H2]glucose, hepatocellular lipids (HCLs), ATP, and inorganic phosphate concentrations with (1)H/(31)P magnetic resonance spectroscopy. Intranasal insulin transiently increased serum insulin levels followed by a gradual lowering of blood glucose in CON only. Fasting HIS index was not affected by intranasal insulin in CON and patients. HCLs decreased by 35% in CON only, whereas absolute hepatic ATP concentration increased by 18% after 3 h. A subgroup of CON received intravenous insulin to mimic the changes in serum insulin and blood glucose levels observed after intranasal insulin. This resulted in a 34% increase in HCLs without altering hepatic ATP concentrations. In conclusion, intranasal insulin does not affect HIS but rapidly improves hepatic energy metabolism in healthy humans, which is independent of peripheral insulinemia. These effects are blunted in patients with type 2 diabetes.
Collapse
Affiliation(s)
- Sofiya Gancheva
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research, Heinrich Heine University Düsseldorf, Düsseldorf, Germany German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Düsseldorf, Germany
| | - Chrysi Koliaki
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research, Heinrich Heine University Düsseldorf, Düsseldorf, Germany German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Düsseldorf, Germany
| | - Alessandra Bierwagen
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research, Heinrich Heine University Düsseldorf, Düsseldorf, Germany German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Düsseldorf, Germany
| | - Peter Nowotny
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research, Heinrich Heine University Düsseldorf, Düsseldorf, Germany German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Düsseldorf, Germany
| | - Martin Heni
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Eberhard Karls University, Tübingen, Germany Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen (Paul Langerhans Institute Tübingen), Tübingen, Germany German Center for Diabetes Research (DZD e.V.), Partner Neuherberg, Neuherberg, Germany
| | - Andreas Fritsche
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Eberhard Karls University, Tübingen, Germany Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen (Paul Langerhans Institute Tübingen), Tübingen, Germany German Center for Diabetes Research (DZD e.V.), Partner Neuherberg, Neuherberg, Germany
| | - Hans-Ulrich Häring
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Eberhard Karls University, Tübingen, Germany Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen (Paul Langerhans Institute Tübingen), Tübingen, Germany German Center for Diabetes Research (DZD e.V.), Partner Neuherberg, Neuherberg, Germany
| | - Julia Szendroedi
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research, Heinrich Heine University Düsseldorf, Düsseldorf, Germany German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Düsseldorf, Germany Department of Endocrinology and Diabetology, University Hospital, Düsseldorf, Germany
| | - Michael Roden
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research, Heinrich Heine University Düsseldorf, Düsseldorf, Germany German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Düsseldorf, Germany Department of Endocrinology and Diabetology, University Hospital, Düsseldorf, Germany
| |
Collapse
|
62
|
Woodcock K, Kierdorf K, Pouchelon C, Vivancos V, Dionne M, Geissmann F. Macrophage-derived upd3 cytokine causes impaired glucose homeostasis and reduced lifespan in Drosophila fed a lipid-rich diet. Immunity 2015; 42:133-44. [PMID: 25601202 PMCID: PMC4304720 DOI: 10.1016/j.immuni.2014.12.023] [Citation(s) in RCA: 107] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 11/11/2014] [Accepted: 12/22/2014] [Indexed: 12/16/2022]
Abstract
Long-term consumption of fatty foods is associated with obesity, macrophage activation and inflammation, metabolic imbalance, and a reduced lifespan. We took advantage of Drosophila genetics to investigate the role of macrophages and the pathway(s) that govern their response to dietary stress. Flies fed a lipid-rich diet presented with increased fat storage, systemic activation of JAK-STAT signaling, reduced insulin sensitivity, hyperglycemia, and a shorter lifespan. Drosophila macrophages produced the JAK-STAT-activating cytokine upd3, in a scavenger-receptor (crq) and JNK-dependent manner. Genetic depletion of macrophages or macrophage-specific silencing of upd3 decreased JAK-STAT activation and rescued insulin sensitivity and the lifespan of Drosophila, but did not decrease fat storage. NF-κB signaling made no contribution to the phenotype observed. These results identify an evolutionarily conserved “scavenger receptor-JNK-type 1 cytokine” cassette in macrophages, which controls glucose metabolism and reduces lifespan in Drosophila maintained on a lipid-rich diet via activation of the JAK-STAT pathway. Chronic lipid-rich diet results in JAK-STAT activation in Drosophila Chronic JAK-STAT activation reduces lifespan and insulin sensitivity Lipid-rich diet induces JNK pathway-dependent production of upd3 by macrophages Macrophage upd3 controls JAK-STAT activation, survival, and insulin sensitivity
Collapse
Affiliation(s)
- Katie J. Woodcock
- Centre for Molecular and Cellular Biology of Inflammation (CMCBI), Division of Immunity, Infection, and Inflammatory diseases, King’s College London, London SE1 1UL, UK
| | - Katrin Kierdorf
- Centre for Molecular and Cellular Biology of Inflammation (CMCBI), Division of Immunity, Infection, and Inflammatory diseases, King’s College London, London SE1 1UL, UK
| | - Clara A. Pouchelon
- Centre for Molecular and Cellular Biology of Inflammation (CMCBI), Division of Immunity, Infection, and Inflammatory diseases, King’s College London, London SE1 1UL, UK
| | - Valérie Vivancos
- Centre for Molecular and Cellular Biology of Inflammation (CMCBI), Division of Immunity, Infection, and Inflammatory diseases, King’s College London, London SE1 1UL, UK
| | - Marc S. Dionne
- Centre for Molecular and Cellular Biology of Inflammation (CMCBI), Division of Immunity, Infection, and Inflammatory diseases, King’s College London, London SE1 1UL, UK
| | - Frédéric Geissmann
- Centre for Molecular and Cellular Biology of Inflammation (CMCBI), Division of Immunity, Infection, and Inflammatory diseases, King’s College London, London SE1 1UL, UK
- Corresponding author
| |
Collapse
|
63
|
Tucci S, Flögel U, Spiekerkoetter U. Sexual dimorphism of lipid metabolism in very long-chain acyl-CoA dehydrogenase deficient (VLCAD-/-) mice in response to medium-chain triglycerides (MCT). Biochim Biophys Acta Mol Basis Dis 2015; 1852:1442-50. [PMID: 25887160 DOI: 10.1016/j.bbadis.2015.04.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 03/17/2015] [Accepted: 04/07/2015] [Indexed: 02/08/2023]
Abstract
Medium-chain triglycerides (MCT) are widely applied in the treatment of long-chain fatty acid oxidation disorders. Previously it was shown that long-term MCT supplementation strongly affects lipid metabolism in mice. We here investigate sex-specific effects in mice with very-long-chain-acyl-CoA dehydrogenase (VLCAD) deficiency in response to a long-term MCT modified diet. We quantified blood lipids, acylcarnitines, glucose, insulin and free fatty acids, as well as tissue triglycerides in the liver and skeletal muscle under a control and an MCT diet over 1 year. In addition, visceral and hepatic fat content and muscular intramyocellular lipids (IMCL) were assessed by in vivo(1)H magnetic resonance spectroscopy (MRS) techniques. The long-term application of an MCT diet induced a marked alteration of glucose homeostasis. However, only VLCAD-/- female mice developed a severe metabolic syndrome characterized by marked insulin resistance, dyslipidemia, severe hepatic and visceral steatosis, whereas VLCAD-/- males seemed to be protected and only presented with milder insulin resistance. Moreover, the highly saturated MCT diet is associated with a decreased hepatic stearoyl-CoA desaturase 1 (SCD1) activity in females aggravating the harmful effects of a saturated MCT diet. Long-term MCT supplementation deeply affects lipid metabolism in a sexual dimorphic manner resulting in a severe metabolic syndrome only in female mice. These findings are striking since the first signs of insulin resistance already occur in female VLCAD-/- mice during their reproductive period. How these metabolic adaptations are finally regulated needs to be determined. More important, the relevance of these findings for humans under these dietary modifications needs to be investigated.
Collapse
Affiliation(s)
- Sara Tucci
- Department of General Pediatrics, Center for Pediatrics and Adolescent Medicine, University Hospital Freiburg, 79106 Freiburg, Germany.
| | - Ulrich Flögel
- Department of Molecular Cardiology, Heinrich-Heine-University Duesseldorf, 40225 Düsseldorf, Germany
| | - Ute Spiekerkoetter
- Department of General Pediatrics, Center for Pediatrics and Adolescent Medicine, University Hospital Freiburg, 79106 Freiburg, Germany
| |
Collapse
|
64
|
Yang Y, Feng Y, Ma X, Chen K, Wu N, Wang D, Li P, Wang M, Li Q, Zhang J. Visceral adiposity index and insulin secretion and action in first-degree relatives of subjects with type 2 diabetes. Diabetes Metab Res Rev 2015; 31:315-21. [PMID: 25351905 DOI: 10.1002/dmrr.2615] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 10/06/2014] [Accepted: 10/11/2014] [Indexed: 01/03/2023]
Abstract
BACKGROUND To explore the predictive performance of the newly established visceral adiposity index for diabetes and prediabetes, as well as the relationships between the visceral adiposity index and the parameters of insulin secretion and action. METHODS Eight hundred twenty-four first-degree relatives of individuals with type 2 diabetes who had no known history of abnormal glucose regulation were selected. Diabetes and prediabetes were diagnosed using the standard oral glucose tolerance test. RESULTS The visceral adiposity index values were greater for the subjects with prediabetes and diabetes than for those with normal glucose regulation. Among the subjects with normal glucose regulation, the visceral adiposity index was higher for those whose levels were above the median value of the incremental area under the curve for glucose than for the subjects whose levels fell below the median value. The visceral adiposity index was negatively correlated with the homeostasis model assessment of the β-cell function index (Homa-β) and with the insulinogenic index (ΔI30 /ΔG30 ). The visceral adiposity index was found to be a valuable predictor of diabetes, but it was not superior to triglyceride levels, waist circumference, or lipid accumulation production. CONCLUSIONS The first degree relatives of people with type 2 DM who have prediabetes or diabetes have progressively higher visceral adiposity index in association with progressive hyperglycemia, and it was found to correlate with the Homa-β and the ΔI30 /ΔG30 .
Collapse
Affiliation(s)
- Yumei Yang
- Second Affiliated Hospital of Harbin Mecical University, Department of Endocrinology and Metabolism, Harbin, Heilongjiang, China; Yiwu Affiliated Hospital, Zhejiang University School of Medicine, Department of Endocrinology and Metabolism, Hangzhou, Zhengjiang, China
| | | | | | | | | | | | | | | | | | | |
Collapse
|
65
|
Gu M, Mordwinkin NM, Kooreman NG, Lee J, Wu H, Hu S, Churko JM, Diecke S, Burridge PW, He C, Barron FE, Ong SG, Gold JD, Wu JC. Pravastatin reverses obesity-induced dysfunction of induced pluripotent stem cell-derived endothelial cells via a nitric oxide-dependent mechanism. Eur Heart J 2014; 36:806-16. [PMID: 25368203 DOI: 10.1093/eurheartj/ehu411] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 09/23/2014] [Indexed: 12/11/2022] Open
Abstract
AIMS High-fat diet-induced obesity (DIO) is a major contributor to type II diabetes and micro- and macro-vascular complications leading to peripheral vascular disease (PVD). Metabolic abnormalities of induced pluripotent stem cell-derived endothelial cells (iPSC-ECs) from obese individuals could potentially limit their therapeutic efficacy for PVD. The aim of this study was to compare the function of iPSC-ECs from normal and DIO mice using comprehensive in vitro and in vivo assays. METHODS AND RESULTS Six-week-old C57Bl/6 mice were fed with a normal or high-fat diet. At 24 weeks, iPSCs were generated from tail tip fibroblasts and differentiated into iPSC-ECs using a directed monolayer approach. In vitro functional analysis revealed that iPSC-ECs from DIO mice had significantly decreased capacity to form capillary-like networks, diminished migration, and lower proliferation. Microarray and ELISA confirmed elevated apoptotic, inflammatory, and oxidative stress pathways in DIO iPSC-ECs. Following hindlimb ischaemia, mice receiving intramuscular injections of DIO iPSC-ECs had significantly decreased reperfusion compared with mice injected with control healthy iPSC-ECs. Hindlimb sections revealed increased muscle atrophy and presence of inflammatory cells in mice receiving DIO iPSC-ECs. When pravastatin was co-administered to mice receiving DIO iPSC-ECs, a significant increase in reperfusion was observed; however, this beneficial effect was blunted by co-administration of the nitric oxide synthase inhibitor, N(ω)-nitro-l-arginine methyl ester. CONCLUSION This is the first study to provide evidence that iPSC-ECs from DIO mice exhibit signs of endothelial dysfunction and have suboptimal efficacy following transplantation in a hindlimb ischaemia model. These findings may have important implications for future treatment of PVD using iPSC-ECs in the obese population.
Collapse
Affiliation(s)
- Mingxia Gu
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA, USA Division of Cardiology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Nicholas M Mordwinkin
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA, USA Division of Cardiology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Nigel G Kooreman
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA, USA Division of Cardiology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA Department of Vascular Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | - Jaecheol Lee
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA, USA Division of Cardiology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Haodi Wu
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA, USA Division of Cardiology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Shijun Hu
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA, USA Division of Cardiology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Jared M Churko
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA, USA Division of Cardiology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Sebastian Diecke
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA, USA Division of Cardiology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Paul W Burridge
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA, USA Division of Cardiology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Chunjiang He
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA, USA Division of Cardiology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Frances E Barron
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA, USA Division of Cardiology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Sang-Ging Ong
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA, USA Division of Cardiology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Joseph D Gold
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA
| | - Joseph C Wu
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA, USA Division of Cardiology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| |
Collapse
|
66
|
Winhofer Y, Wolf P, Krššák M, Wolfsberger S, Tura A, Pacini G, Gessl A, Raber W, Kukurova IJ, Kautzky-Willer A, Knosp E, Trattnig S, Krebs M, Luger A. No evidence of ectopic lipid accumulation in the pathophysiology of the acromegalic cardiomyopathy. J Clin Endocrinol Metab 2014; 99:4299-306. [PMID: 25148232 DOI: 10.1210/jc.2014-2242] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT PATIENTS with acromegaly frequently display disturbances of glucose and lipid metabolism, which might contribute to their increased cardiovascular risk. Because insulin resistance and increased lipolysis have been linked to ectopic lipid deposition, altered lipid accumulation in the liver and the myocardium might contribute to metabolic and cardiac complications in these patients. OBJECTIVE The aim of this study was to investigate myocardial (MYCL) and hepatic lipid content (HCL), insulin sensitivity, and cardiac function in active acromegaly and after control of GH excess through transsphenoidal surgery. PATIENTS Ten patients with newly diagnosed acromegaly (ACRO_active) were compared with 12 healthy controls (CON), matched for age, body mass index, and gender. In seven patients GH excess was controlled, and they were compared with their active state. METHODS MYCL and HCL were assessed by (1)H-magnetic resonance spectroscopy, pericardial fat and cardiac function by (1)H-magnetic resonance imaging, and insulin sensitivity and secretion by an oral glucose tolerance test. RESULTS Although MYCL tended to be lower, HCL was significantly lower in ACRO_active compared with CON (HCL: 1.2% ± 1.2% vs 4.3% ± 3.5% of (1)H-magnetic resonance spectroscopy signal, P < .02). Parameters of systolic function and hypertrophy were significantly increased in ACRO_active compared with CON, as were insulin secretion and resistance. After the control of GH excess, HCL and MYCL remained unchanged, but pericardial fat was increased in the patients in whom GH excess was controlled (from 11.6 ± 5.5 to 14.7 ± 6.2 cm(2), P = .02). CONCLUSION Acromegaly represents a unique condition characterized by low myocardial and hepatic lipid content despite decreased insulin sensitivity, hyperinsulinemia, and hyperglycemia. Hence, ectopic lipid accumulation does not appear to contribute to cardiac morbidity, and increased lipid oxidation might counteract ectopic lipid accumulation in GH excess.
Collapse
Affiliation(s)
- Yvonne Winhofer
- Department of Internal Medicine III, Division of Endocrinology and Metabolism (Y.W., P.W., M.Krš., A.G., W.R., A.K.-W., M.Kre., A.L.), Department of Biomedical Imaging and Image Guided therapy, Centre of Excellence High-field MR (M.Krš., I.J.K., S.T.), and Department of Neurosurgery (S.W., E.K.), Medical University of Vienna, A-1090 Vienna, Austria; and Institute of Biomedical Engineering (A.T., G.P.), National Research Council, Metabolic Unit, I-35127 Padova, Italy
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
67
|
Ross JS, Russo SB, Chavis GC, Cowart LA. Sphingolipid regulators of cellular dysfunction in Type 2 diabetes mellitus: a systems overview. ACTA ACUST UNITED AC 2014. [DOI: 10.2217/clp.14.37] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
|
68
|
Dietary high-fat lard intake induces thyroid dysfunction and abnormal morphology in rats. Acta Pharmacol Sin 2014; 35:1411-20. [PMID: 25263336 DOI: 10.1038/aps.2014.82] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Accepted: 07/05/2014] [Indexed: 12/11/2022] Open
Abstract
AIM Excess dietary fat intake can induce lipotoxicity in non-adipose tissues. The aim of this study was to observe the effects of dietary high-fat lard intake on thyroid in rats. METHODS Male Sprague-Dawley rats were fed a high-fat lard diet for 24 weeks, and then the rats were fed a normal control diet (acute dietary modification) or the high-fat lard diet for another 6 weeks. The serum lipid profile, total thyroxine (TT4), free thyroxine (FT4) and thyrotropin (TSH) levels were determined at the 12, 18, 24 and 30 weeks. High-frequency ultrasound scanning of the thyroid glands was performed at the 24 or 30 weeks. After the rats were sacrificed, the thyroid glands were collected for histological and immunohistochemical analyses. RESULTS The high-fat lard diet significantly increased triglyceride levels in both the serum and thyroid, and decreased serum TT4 and FT4 levels in parallel with elevated serum TSH levels. Ultrasonic imaging revealed enlarged thyroid glands with lowered echotexture and relatively heterogeneous features in the high-fat lard fed rats. The thyroid glands from the high-fat lard fed rats exhibited enlarged follicle cavities and flattened follicular epithelial cells under light microscopy, and dilated endoplasmic reticulum cisternae, twisted nuclei, fewer microvilli and secretory vesicles under transmission electron microscopy. Furthermore, the thyroid glands from the high-fat lard fed rats showed markedly low levels of thyroid hormone synthesis-related proteins TTF-1 and NIS. Acute dietary modification by withdrawal of the high-fat lard diet for 6 weeks failed to ameliorate the high-fat lard diet-induced thyroid changes. CONCLUSION Dietary high-fat lard intake induces significant thyroid dysfunction and abnormal morphology in rats, which can not be corrected by short-term dietary modification.
Collapse
|
69
|
FTO is a relevant factor for the development of the metabolic syndrome in mice. PLoS One 2014; 9:e105349. [PMID: 25144618 PMCID: PMC4140775 DOI: 10.1371/journal.pone.0105349] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Accepted: 07/23/2014] [Indexed: 12/19/2022] Open
Abstract
The metabolic syndrome is a worldwide problem mainly caused by obesity. FTO was found to be a obesity-risk gene in humans and FTO deficiency in mice led to reduction in adipose tissue. Thus, FTO is an important factor for the development of obesity. Leptin-deficient mice are a well characterized model for analysing the metabolic syndrome. To determine the relevance of FTO for the development of the metabolic syndrome we analysed different parameters in combined homozygous deficient mice (Lep(ob/ob);Fto(-/-)). Lep(ob/ob);Fto(-/-) mice showed an improvement in analysed hallmarks of the metabolic syndrome in comparison to leptin-deficient mice wild type or heterozygous for Fto. Lep(ob/ob);Fto(-/-) mice did not develop hyperglycaemia and showed an improved glucose tolerance. Furthermore, extension of beta-cell mass was prevented in Lep(ob/ob);Fto(-/-)mice and accumulation of ectopic fat in the liver was reduced. In conclusion this study demonstrates that FTO deficiency has a protective effect not only on the development of obesity but also on the metabolic syndrome. Thus, FTO plays an important role in the development of metabolic disorders and is an interesting target for therapeutic agents.
Collapse
|
70
|
Thomaseth K, Brehm A, Pavan A, Pacini G, Roden M. Modeling glucose and free fatty acid kinetics during insulin-modified intravenous glucose tolerance test in healthy humans: role of counterregulatory response. Am J Physiol Regul Integr Comp Physiol 2014; 307:R321-31. [DOI: 10.1152/ajpregu.00314.2013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Insulin administration during insulin-modified intravenous glucose tolerance test (IM-IVGTT) can induce transient hypoglycemia in healthy insulin-sensitive subjects. This triggers counterregulatory reflex (CRR) responses, which influence the kinetics of glucose and nonesterified fatty acids (NEFA), and undermines the accuracy of mathematical modeling methods that do not explicitly account for CRR. The aim of this study is to evaluate mathematical models of glucose and NEFA kinetics against experimental data in the presence or absence of CRR. Thirteen healthy nondiabetic subjects underwent a standard IM-IVGTT and a modified test (GC-IM-IVGTT) with a variable glucose infusion preventing hypoglycemia. While model predictions fit very well with glucose and NEFA data from GC-IM-IVGTT, they lagged behind observations from IM-IVGTT during recovery from hypoglycemia, independently of insulinemia, which did not differ significantly between protocols. A modification to the glucose minimal model, using the glucose concentration below a threshold as a signal for CRR, improves model predictions for both glucose and NEFA. The associated increase in endogenous glucose production correlates, among various CRR hormones, mainly with the dynamics of glucagon concentration. The modified minimal models introduce new parameters that quantify strength and duration of CRR following hypoglycemia. Although CRR represents an unwanted side-effect in IM-IVGTT occurring only in insulin-sensitive subjects, this study provides new insights leading to improved procedures for estimating insulin sensitivity from IM-IVGTT, which may also allow for assessing the individual capacity of recovery from hypoglycemic events in patients treated with insulin or insulin-releasing drugs.
Collapse
Affiliation(s)
- Karl Thomaseth
- Institute of Biomedical Engineering, National Research Council, Padua, Italy
| | - Attila Brehm
- Karl-Landsteiner Institute for Endocrinology and Metabolism at 1st Medical Department, Hanusch Hospital, Vienna, Austria
| | - Alessandra Pavan
- Institute of Biomedical Engineering, National Research Council, Padua, Italy
| | - Giovanni Pacini
- Institute of Biomedical Engineering, National Research Council, Padua, Italy
| | - Michael Roden
- Department of Endocrinology and Diabetology, University Hospital, Düsseldorf, Germany; and
- German Center for Diabetes Research, Düsseldorf, Germany
| |
Collapse
|
71
|
Menart-Houtermans B, Rütter R, Nowotny B, Rosenbauer J, Koliaki C, Kahl S, Simon MC, Szendroedi J, Schloot NC, Roden M. Leukocyte profiles differ between type 1 and type 2 diabetes and are associated with metabolic phenotypes: results from the German Diabetes Study (GDS). Diabetes Care 2014; 37:2326-33. [PMID: 25061140 DOI: 10.2337/dc14-0316] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Altered immune reactivity precedes and accompanies type 1 and type 2 diabetes. We hypothesized that the metabolic phenotype relates to the systemic cellular immune status. RESEARCH DESIGN AND METHODS A total of 194 metabolically well-controlled patients with type 1 diabetes (n = 62, mean diabetes duration 1.29 years) or type 2 diabetes (n = 132, 1.98 years) and 60 normoglycemic persons underwent blood sampling for automated white blood cell counting (WBC) and flow cytometry. Whole-body insulin sensitivity was measured with hyperinsulinemic-euglycemic clamp tests. RESULTS Patients with type 2 diabetes had higher WBC counts than control subjects along with a higher percentage of T cells and activated T helper (Th) and cytotoxic T (Tc) cells but lower proportions of natural killer (NK) cells. In type 1 diabetes, the percentage of activated Th and Tc cells was also higher compared with control subjects, whereas the ratio of regulatory T (Treg) cells to activated Th cells was lower, suggesting diminished regulatory capacity. Parameters of glycemic control related positively to Treg cells only in type 2 diabetes. Upon age, sex, and body mass adjustments, insulin sensitivity correlated positively with monocytes, while circulating lipids correlated positively with T cell subsets in type 1 diabetes. CONCLUSIONS Immune cell phenotypes showed distinct frequencies of occurrence in both diabetes types and associate with insulin sensitivity, glycemia, and lipidemia.
Collapse
Affiliation(s)
- Barbara Menart-Houtermans
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University, Düsseldorf, GermanyGerman Center for Diabetes Research, Partner Düsseldorf, Düsseldorf, Germany
| | - Ruth Rütter
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University, Düsseldorf, GermanyGerman Center for Diabetes Research, Partner Düsseldorf, Düsseldorf, Germany
| | - Bettina Nowotny
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University, Düsseldorf, Germany
| | - Joachim Rosenbauer
- German Center for Diabetes Research, Partner Düsseldorf, Düsseldorf, GermanyInstitute for Biometrics and Epidemiology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University, Düsseldorf, Germany
| | - Chrysi Koliaki
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University, Düsseldorf, GermanyGerman Center for Diabetes Research, Partner Düsseldorf, Düsseldorf, Germany
| | - Sabine Kahl
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University, Düsseldorf, GermanyGerman Center for Diabetes Research, Partner Düsseldorf, Düsseldorf, Germany
| | - Marie-Christine Simon
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University, Düsseldorf, GermanyGerman Center for Diabetes Research, Partner Düsseldorf, Düsseldorf, Germany
| | - Julia Szendroedi
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University, Düsseldorf, GermanyGerman Center for Diabetes Research, Partner Düsseldorf, Düsseldorf, GermanyDepartment of Endocrinology and Diabetology, University Clinics Düsseldorf, Heinrich-Heine University, Düsseldorf, Germany
| | - Nanette C Schloot
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University, Düsseldorf, Germany
| | - Michael Roden
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University, Düsseldorf, GermanyGerman Center for Diabetes Research, Partner Düsseldorf, Düsseldorf, GermanyDepartment of Endocrinology and Diabetology, University Clinics Düsseldorf, Heinrich-Heine University, Düsseldorf, Germany
| | | |
Collapse
|
72
|
Ectopic fat storage in the pancreas using 1H-MRS: importance of diabetic status and modulation with bariatric surgery-induced weight loss. Int J Obes (Lond) 2014; 39:480-7. [PMID: 25042860 DOI: 10.1038/ijo.2014.126] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Revised: 07/08/2014] [Accepted: 07/16/2014] [Indexed: 02/06/2023]
Abstract
OBJECTIVES Recent literature suggests that ectopic fat deposition in the pancreas may contribute to endocrine and exocrine organ dysfunction, such as type 2 diabetes (T2D), pancreatitis or pancreatic cancer. The aim of this study was to determine factors associated with pancreatic triglyceride content (PTGC), and to investigate the impact of bariatric surgery on ectopic fat pads, pancreatic fat (PTGC) and hepatic fat (HTGC). SUBJECTS In all, 45 subjects (13 lean, 13 obese nondiabetics and 19 T2D, matched for age and gender) underwent 1H-magnetic resonance spectroscopy, computed tomography of the visceral abdominal fat, metabolic and lipidomic analysis, including insulin-resistance homeostasis model assessment (HOMA-IR), insulin-secretion homeostasis model assessment (HOMA-B) and plasma fatty-acid composition. Twenty obese subjects were reassessed 6 months after the bariatric surgery. RESULTS PTGC was significantly higher in type 2 diabetic subjects (23.8±3.2%) compared with obese (14.0±3.3; P=0.03) and lean subjects (7.5±0.9%; P=0.0002). PTGC remained significantly associated with T2D after adjusting for age and sex (β=0.47; P=0.004) or even after adjusting for waist circumference, triglycerides and HOMA-IR (β=0.32; P=0.04). T2D, C18:1n-9 (oleic acid), uric acid, triglycerides and plasminogen activator inhibitor-1 were the five more important parameters involved in PTGC prediction (explained 80% of PTGC variance). Bariatric surgery induced a huge reduction of both HTGC (-51.2±7.9%) and PTGC (-43.8±7.0%) reaching lean levels, whereas body mass index remained greatly elevated. An improvement of insulin resistance HOMA-IR and no change in HOMA-B were observed after bariatric surgery. The PTGC or HTGC losses were not correlated, suggesting tissue-specific mobilization of these ectopic fat stores. CONCLUSION Pancreatic fat increased with T2D and drastically decreased after the bariatric surgery. This suggests that decreased PTGC may contribute to improved beta cell function seen after the bariatric surgery. Further, long-term interventional studies are warranted to examine this hypothesis and to determine the degree to which ectopic fat mobilization may mediate the improvement in endocrine and exocrine pancreatic functions.
Collapse
|
73
|
Hage Hassan R, Bourron O, Hajduch E. Defect of insulin signal in peripheral tissues: Important role of ceramide. World J Diabetes 2014; 5:244-257. [PMID: 24936246 PMCID: PMC4058729 DOI: 10.4239/wjd.v5.i3.244] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Revised: 01/29/2014] [Accepted: 05/08/2014] [Indexed: 02/05/2023] Open
Abstract
In healthy people, balance between glucose production and its utilization is precisely controlled. When circulating glucose reaches a critical threshold level, pancreatic β cells secrete insulin that has two major actions: to lower circulating glucose levels by facilitating its uptake mainly into skeletal muscle while inhibiting its production by the liver. Interestingly, dietary triglycerides are the main source of fatty acids to fulfill energy needs of oxidative tissues. Normally, the unconsumed fraction of excess of fatty acids is stored in lipid droplets that are localized in adipocytes to provide energy during fasting periods. Thus, adipose tissue acts as a trap for fatty acid excess liberated from plasma triglycerides. When the buffering action of adipose tissue to store fatty acids is impaired, fatty acids that build up in other tissues are metabolized as sphingolipid derivatives such as ceramides. Several studies suggest that ceramides are among the most active lipid second messengers to inhibit the insulin signaling pathway and this review describes the major role played by ceramide accumulation in the development of insulin resistance of peripherals tissues through the targeting of specific proteins of the insulin signaling pathway.
Collapse
|
74
|
Berglund L, Brunzell JD, Goldberg AC, Goldberg IJ, Stalenhoef A. Treatment options for hypertriglyceridemia: from risk reduction to pancreatitis. Best Pract Res Clin Endocrinol Metab 2014; 28:423-37. [PMID: 24840268 PMCID: PMC4028601 DOI: 10.1016/j.beem.2013.10.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
While there has been considerable focus on the role and treatment of LDL cholesterol levels, a definitive role of triglycerides in the management of cardiovascular disease has been uncertain. Notably, with increasing triglyceride levels, there is a parallel increase in cholesterol levels carried by triglyceride-rich lipoproteins, which has prompted interest in the use of non-HDL cholesterol levels as a tool guiding interventions. Recent studies have provided evidence for an independent role of triglyceride levels as a cardiovascular risk factor, and recently, an Endocrine Society guideline was published for treatment of hypertriglyceridemia. In contrast to the relative uncertainty regarding triglycerides and cardiovascular disease, a role of very high triglyceride levels as a risk factor for pancreatitis has been well known. The present paper summarizes the underlying evidence for a risk role for triglyceride levels in cardiovascular disease and pancreatitis, current treatment recommendations and areas of future research.
Collapse
Affiliation(s)
- Lars Berglund
- Department of Medicine, University of California, Davis, CA, USA; Department of Veterans Affairs, Northern California Health Care System, 2921 Stockton Blvd, Suite 1400, Sacramento, CA 95817, USA.
| | - John D Brunzell
- Department of Medicine, University of Washington, School of Medicine, 1959 NE Pacific Street, UW Mailbox 356426, Seattle, WA 98195-6426, USA.
| | - Anne C Goldberg
- Department of Medicine, Washington University School of Medicine, Campus Box 8127, 660 South Euclid, St. Louis, MO 63110, USA.
| | - Ira J Goldberg
- Department of Medicine, Columbia University, Presbyterian Hospital, PH 10-305, 622 West 168th Street, New York, NY 10032, USA.
| | - Anton Stalenhoef
- Department of Medicine, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
| |
Collapse
|
75
|
Ader M, Stefanovski D, Kim SP, Richey JM, Ionut V, Catalano KJ, Hucking K, Ellmerer M, Van Citters G, Hsu IR, Chiu JD, Woolcott OO, Harrison LN, Zheng D, Lottati M, Kolka CM, Mooradian V, Dittmann J, Yae S, Liu H, Castro AVB, Kabir M, Bergman RN. Hepatic insulin clearance is the primary determinant of insulin sensitivity in the normal dog. Obesity (Silver Spring) 2014; 22:1238-45. [PMID: 24123967 PMCID: PMC3969862 DOI: 10.1002/oby.20625] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Revised: 08/15/2013] [Accepted: 09/10/2013] [Indexed: 01/17/2023]
Abstract
OBJECTIVE Insulin resistance is a powerful risk factor for Type 2 diabetes and a constellation of chronic diseases, and is most commonly associated with obesity. We examined if factors other than obesity are more substantial predictors of insulin sensitivity under baseline, nonstimulated conditions. METHODS Metabolic assessment was performed in healthy dogs (n = 90). Whole-body sensitivity from euglycemic clamps (SICLAMP ) was the primary outcome variable, and was measured independently by IVGTT (n = 36). Adiposity was measured by MRI (n = 90), and glucose-stimulated insulin response was measured from hyperglycemic clamp or IVGTT (n = 86 and 36, respectively). RESULTS SICLAMP was highly variable (5.9-75.9 dl/min per kg per μU/ml). Despite narrow range of body weight (mean, 28.7 ± 0.3 kg), adiposity varied approximately eight-fold and was inversely correlated with SICLAMP (P < 0.025). SICLAMP was negatively associated with fasting insulin, but most strongly associated with insulin clearance. Clearance was the dominant factor associated with sensitivity (r = 0.53, P < 0.00001), whether calculated from clamp or IVGTT. CONCLUSIONS These data suggest that insulin clearance contributes substantially to insulin sensitivity, and may be pivotal in understanding the pathogenesis of insulin resistance. We propose the hyperinsulinemia due to reduction in insulin clearance is responsible for insulin resistance secondary to changes in body weight.
Collapse
Affiliation(s)
- Marilyn Ader
- Diabetes and Obesity Research Institute, Cedars-Sinai Medical Center, Los Angeles, California
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
76
|
Granér M, Pentikäinen MO, Nyman K, Siren R, Lundbom J, Hakkarainen A, Lauerma K, Lundbom N, Nieminen MS, Petzold M, Taskinen MR. Cardiac steatosis in patients with dilated cardiomyopathy. Heart 2014; 100:1107-12. [DOI: 10.1136/heartjnl-2013-304961] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
|
77
|
Tarantal AF, Berglund L. Obesity and lifespan health--importance of the fetal environment. Nutrients 2014; 6:1725-36. [PMID: 24763115 PMCID: PMC4011063 DOI: 10.3390/nu6041725] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Revised: 04/09/2014] [Accepted: 04/15/2014] [Indexed: 02/02/2023] Open
Abstract
A marked increase in the frequency of obesity at the population level has resulted in an increasing number of obese women entering pregnancy. The increasing realization of the importance of the fetal environment in relation to chronic disease across the lifespan has focused attention on the role of maternal obesity in fetal development. Previous studies have demonstrated that obesity during adolescence and adulthood can be traced back to fetal and early childhood exposures. This review focuses on factors that contribute to early developmental events, such as epigenetic modifications, the potential for an increase in inflammatory burden, early developmental programming changes such as the variable development of white versus brown adipose tissue, and alterations in organ ontogeny. We hypothesize that these mechanisms promote an unfavorable fetal environment and can have a long-standing impact, with early manifestations of chronic disease that can result in an increased demand for future health care. In order to identify appropriate preventive measures, attention needs to be placed both on reducing maternal obesity as well as understanding the molecular, cellular, and epigenetic mechanisms that may be responsible for the prenatal onset of chronic disease.
Collapse
Affiliation(s)
- Alice F Tarantal
- Department of Pediatrics, School of Medicine, University of California, Davis, CA 95616, USA.
| | - Lars Berglund
- Department of Medicine, School of Medicine, University of California, Davis, CA 95616, USA.
| |
Collapse
|
78
|
Franko A, von Kleist-Retzow JC, Neschen S, Wu M, Schommers P, Böse M, Kunze A, Hartmann U, Sanchez-Lasheras C, Stoehr O, Huntgeburth M, Brodesser S, Irmler M, Beckers J, de Angelis MH, Paulsson M, Schubert M, Wiesner RJ. Liver adapts mitochondrial function to insulin resistant and diabetic states in mice. J Hepatol 2014; 60:816-23. [PMID: 24291365 DOI: 10.1016/j.jhep.2013.11.020] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Revised: 11/18/2013] [Accepted: 11/19/2013] [Indexed: 12/04/2022]
Abstract
BACKGROUND & AIMS To determine if diabetic and insulin-resistant states cause mitochondrial dysfunction in liver or if there is long term adaptation of mitochondrial function to these states, mice were (i) fed with a high-fat diet to induce obesity and T2D (HFD), (ii) had a genetic defect in insulin signaling causing whole body insulin resistance, but not full blown T2D (IR/IRS-1(+/-) mice), or (iii) were analyzed after treatment with streptozocin (STZ) to induce a T1D-like state. METHODS Hepatic lipid levels were measured by thin layer chromatography. Mitochondrial respiratory chain (RC) levels and function were determined by Western blot, spectrophotometric, oxygen consumption and proton motive force analysis. Gene expression was analyzed by real-time PCR and microarray. RESULTS HFD caused insulin resistance and hepatic lipid accumulation, but RC was largely unchanged. Livers from insulin resistant IR/IRS-1(+/-) mice had normal lipid contents and a normal RC, but mitochondria were less well coupled. Livers from severely hyperglycemic and hypoinsulinemic STZ mice had massively depleted lipid levels, but RC abundance was unchanged. However, liver mitochondria isolated from these animals showed increased abundance and activity of the RC, which was better coupled. CONCLUSIONS Insulin resistance, induced either by obesity or genetic manipulation and steatosis do not cause mitochondrial dysfunction in mouse liver. Also, mitochondrial dysfunction is not a prerequisite for liver steatosis. However, severe insulin deficiency and high blood glucose levels lead to an enhanced performance and better coupling of the RC. This may represent an adaptation to fuel overload and the high energy-requirement of an unsuppressed gluconeogenesis.
Collapse
Affiliation(s)
- Andras Franko
- Center for Physiology and Pathophysiology, Institute of Vegetative Physiology, University of Köln, 50931 Köln, Germany; Institute of Experimental Genetics, Helmholtz Zentrum München GmbH, 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), 85764 Neuherberg, Germany
| | - Jürgen-Christoph von Kleist-Retzow
- Center for Physiology and Pathophysiology, Institute of Vegetative Physiology, University of Köln, 50931 Köln, Germany; Department of Pediatrics, University of Köln, 50924 Köln, Germany; Center for Molecular Medicine Cologne, CMMC, University of Köln, 50931 Köln, Germany
| | - Susanne Neschen
- Institute of Experimental Genetics, Helmholtz Zentrum München GmbH, 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), 85764 Neuherberg, Germany
| | - Moya Wu
- Institute of Experimental Genetics, Helmholtz Zentrum München GmbH, 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), 85764 Neuherberg, Germany
| | - Philipp Schommers
- Center for Physiology and Pathophysiology, Institute of Vegetative Physiology, University of Köln, 50931 Köln, Germany
| | - Marlen Böse
- Center for Physiology and Pathophysiology, Institute of Vegetative Physiology, University of Köln, 50931 Köln, Germany
| | - Alexander Kunze
- Department of Biochemistry, University of Köln, 50931 Köln, Germany
| | - Ursula Hartmann
- Department of Biochemistry, University of Köln, 50931 Köln, Germany
| | - Carmen Sanchez-Lasheras
- Department of Mouse Genetics and Metabolism, Institute for Genetics, University of Köln, 50674 Köln, Germany
| | - Oliver Stoehr
- Center for Endocrinology, Diabetes and Preventive Medicine, University of Köln, 50937 Köln, Germany
| | - Michael Huntgeburth
- Department of Internal Medicine III, University of Köln, 50937 Köln, Germany
| | - Susanne Brodesser
- Institute for Medical Microbiology, Immunology and Hygiene, University of Köln, 50935 Köln, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), 50674 Köln, Germany
| | - Martin Irmler
- Institute of Experimental Genetics, Helmholtz Zentrum München GmbH, 85764 Neuherberg, Germany
| | - Johannes Beckers
- Institute of Experimental Genetics, Helmholtz Zentrum München GmbH, 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), 85764 Neuherberg, Germany; Technische Universität München, WZW - Center of Life and Food Science Weihenstephan, Chair of Experimental Genetics, 85350 Freising-Weihenstephan, Germany
| | - Martin Hrabé de Angelis
- Institute of Experimental Genetics, Helmholtz Zentrum München GmbH, 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), 85764 Neuherberg, Germany; Technische Universität München, WZW - Center of Life and Food Science Weihenstephan, Chair of Experimental Genetics, 85350 Freising-Weihenstephan, Germany
| | - Mats Paulsson
- Center for Molecular Medicine Cologne, CMMC, University of Köln, 50931 Köln, Germany; Department of Biochemistry, University of Köln, 50931 Köln, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), 50674 Köln, Germany
| | - Markus Schubert
- Center for Molecular Medicine Cologne, CMMC, University of Köln, 50931 Köln, Germany; Center for Endocrinology, Diabetes and Preventive Medicine, University of Köln, 50937 Köln, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), 50674 Köln, Germany.
| | - Rudolf J Wiesner
- Center for Physiology and Pathophysiology, Institute of Vegetative Physiology, University of Köln, 50931 Köln, Germany; Center for Molecular Medicine Cologne, CMMC, University of Köln, 50931 Köln, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), 50674 Köln, Germany.
| |
Collapse
|
79
|
Abstract
PURPOSE OF REVIEW We summarize recent mechanistic and physiological studies related to the role of perilipin 5 (Plin5) in regulating lipid droplet accumulation and protection to fatty acids in tissues with high lipid oxidative metabolism. RECENT FINDINGS Plin5 is a lipid droplet targeting protein that promotes association of lipid droplets with mitochondria and is most highly expressed in oxidative tissues, including cardiac and skeletal muscle. Recent in-vivo and in-vitro data indicate an important role for Plin5 in the regulation of cardiac lipid storage and function. Targeted overexpression of Plin5 in heart causes steatosis, mild mitochondria dysfunction, and hypertrophy in cardiac tissue, but without affecting cardiac function. In contrast, whole body ablation of Plin5 (Plin5 mice) reduces cardiac lipid droplet formation, increases cardiac fatty acid oxidation, and promotes cardiac dysfunction; cardiac defects can be prevented with antioxidative therapy. These data suggest a cytoprotective role for Plin5 to promote lipid storage but to limit fatty acid toxicity, parameters critical for tissues with high lipid oxidative metabolism. SUMMARY In-vivo and in-vitro data suggest that Plin5 is part of a cell-adaptive response to high lipid oxidative metabolism to protect lipid droplet storage against neutral lipases and, so, limit fatty acid accumulation. Although the specific mechanisms that underlie Plin5 lipid droplet storage protection in oxidative tissues remain to be fully elucidated, Plin5 provides a basis for the novel cytoprotective nature of lipid droplets.
Collapse
Affiliation(s)
- Alan R. Kimmel
- Laboratory of Cellular and Developmental Biology (50/3351), National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, United States. ; Tel: 301-496-3016
| | - Carole Sztalryd
- Division of Endocrinology, Department of Medicine, School of Medicine, University of Maryland, Baltimore, Maryland 21201, United States
- The Geriatric Research, Education and Clinical Center, Baltimore Veterans Affairs Health Care Center, Division of Endocrinology, Department of Medicine, School of Medicine, University of Maryland, Baltimore, Maryland 21201, United States. ; Tel: 410-706-4047
| |
Collapse
|
80
|
Mollica MP, Trinchese G, Cavaliere G, De Filippo C, Cocca E, Gaita M, Della-Gatta A, Marano A, Mazzarella G, Bergamo P. c9,t11-Conjugated linoleic acid ameliorates steatosis by modulating mitochondrial uncoupling and Nrf2 pathway. J Lipid Res 2014; 55:837-49. [PMID: 24634500 DOI: 10.1194/jlr.m044032] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Oxidative stress, hepatic steatosis, and mitochondrial dysfunction are key pathophysiological features of nonalcoholic fatty liver disease. A conjugated linoleic acid (CLA) mixture of cis9,trans11 (9,11-CLA) and trans10,cis12 (10,12-CLA) isomers enhanced the antioxidant/detoxifying mechanism via the activation of nuclear factor E2-related factor-2 (Nrf2) and improved mitochondrial function, but less is known about the actions of specific isomers. The differential ability of individual CLA isomers to modulate these pathways was explored in Wistar rats fed for 4 weeks with a lard-based high-fat diet (L) or with control diet (CD), and, within each dietary treatment, two subgroups were daily administered with 9,11-CLA or 10,12-CLA (30 mg/day). The 9,11-CLA, but not 10,12-CLA, supplementation to CD rats improves the GSH/GSSG ratio in the liver, mitochondrial functions, and Nrf2 activity. Histological examination reveals a reduction of steatosis in L-fed rats supplemented with both CLA isomers, but 9,11-CLA downregulated plasma concentrations of proinflammatory markers, mitochondrial dysfunction, and oxidative stress markers in liver more efficiently than in 10,12-CLA treatment. The present study demonstrates the higher protective effect of 9,11-CLA against diet-induced pro-oxidant and proinflammatory signs and suggests that these effects are determined, at least in part, by its ability to activate the Nrf2 pathway and to improve the mitochondrial functioning and biogenesis.
Collapse
Affiliation(s)
- Maria Pina Mollica
- Dipartimento delle Scienze Biologiche, Università degli Studi di Napoli "Federico II," Napoli, Italy
| | | | | | | | | | | | | | | | | | | |
Collapse
|
81
|
Revelo XS, Luck H, Winer S, Winer DA. Morphological and inflammatory changes in visceral adipose tissue during obesity. Endocr Pathol 2014; 25:93-101. [PMID: 24356782 DOI: 10.1007/s12022-013-9288-1] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Obesity is a major health burden worldwide and is a major factor in the development of insulin resistance and metabolic complications such as type II diabetes. Chronic nutrient excess leads to visceral adipose tissue (VAT) expansion and dysfunction in an active process that involves the adipocytes, their supporting matrix, and immune cell infiltrates. These changes contribute to adipose tissue hypoxia, adipocyte cell stress, and ultimately cell death. Accumulation of lymphocytes, macrophages, and other immune cells around dying adipocytes forms the so-called "crown-like structure", a histological hallmark of VAT in obesity. Cross talk between immune cells in adipose tissue dictates the overall inflammatory response, ultimately leading to the production of pro-inflammatory mediators which directly induce insulin resistance in VAT. In this review, we summarize recent studies demonstrating the dramatic changes that occur in visceral adipose tissue during obesity leading to low-grade chronic inflammation and metabolic disease.
Collapse
Affiliation(s)
- Xavier S Revelo
- Division of Cellular & Molecular Biology, Diabetes Research Group, Toronto General Research Institute (TGRI), University Health Network, Toronto, ON, Canada
| | | | | | | |
Collapse
|
82
|
Lecoultre V, Carrel G, Egli L, Binnert C, Boss A, MacMillan EL, Kreis R, Boesch C, Darimont C, Tappy L. Coffee consumption attenuates short-term fructose-induced liver insulin resistance in healthy men. Am J Clin Nutr 2014; 99:268-75. [PMID: 24257718 DOI: 10.3945/ajcn.113.069526] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Epidemiologic and experimental data have suggested that chlorogenic acid, which is a polyphenol contained in green coffee beans, prevents diet-induced hepatic steatosis and insulin resistance. OBJECTIVE We assessed whether the consumption of chlorogenic acid-rich coffee attenuates the effects of short-term fructose overfeeding, dietary conditions known to increase intrahepatocellular lipids (IHCLs), and blood triglyceride concentrations and to decrease hepatic insulin sensitivity in healthy humans. DESIGN Effects of 3 different coffees were assessed in 10 healthy volunteers in a randomized, controlled, crossover trial. IHCLs, hepatic glucose production (HGP) (by 6,6-d2 glucose dilution), and fasting lipid oxidation were measured after 14 d of consumption of caffeinated coffee high in chlorogenic acid (C-HCA), decaffeinated coffee high in chlorogenic acid, or decaffeinated coffee with regular amounts of chlorogenic acid (D-RCA); during the last 6 d of the study, the weight-maintenance diet of subjects was supplemented with 4 g fructose · kg(-1) · d(-1) (total energy intake ± SD: 143 ± 1% of weight-maintenance requirements). All participants were also studied without coffee supplementation, either with 4 g fructose · kg(-1) · d(-1) (high fructose only) or without high fructose (control). RESULTS Compared with the control diet, the high-fructose diet significantly increased IHCLs by 102 ± 36% and HGP by 16 ± 3% and decreased fasting lipid oxidation by 100 ± 29% (all P < 0.05). All 3 coffees significantly decreased HGP. Fasting lipid oxidation increased with C-HCA and D-RCA (P < 0.05). None of the 3 coffees significantly altered IHCLs. CONCLUSIONS Coffee consumption attenuates hepatic insulin resistance but not the increase of IHCLs induced by fructose overfeeding. This effect does not appear to be mediated by differences in the caffeine or chlorogenic acid content. This trial was registered at clinicaltrials.gov as NCT00827450.
Collapse
Affiliation(s)
- Virgile Lecoultre
- Department of Physiology, University of Lausanne, Lausanne, Switzerland (VL, GC, LE, C Binnert, and LT); the Service of Internal Medicine (GC) and the Service of Endocrinology, Diabetes and Metabolism (LT); Lausanne University Hospital, Lausanne, Switzerland; the Department of Clinical Research and Institute of Diagnostic, Interventional, and Pediatric Radiology, University Bern, Bern, Switzerland (AB, ELM, RK, and C Boesch); and Nutrition & Health Research, Nestlé Research Center, Nestec SA, Lausanne, Switzerland (C Binnert and CD)
| | | | | | | | | | | | | | | | | | | |
Collapse
|
83
|
Snogdal LS, Grarup N, Banasik K, Wod M, Jørgensen T, Witte DR, Lauritzen T, Nielsen AA, Brandslund I, Christensen C, Pedersen O, Yderstræde K, Beck-Nielsen H, Henriksen JE, Hansen T, Højlund K. Studies of association of AGPAT6 variants with type 2 diabetes and related metabolic phenotypes in 12,068 Danes. BMC MEDICAL GENETICS 2013; 14:113. [PMID: 24156295 PMCID: PMC4231429 DOI: 10.1186/1471-2350-14-113] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Accepted: 10/21/2013] [Indexed: 01/23/2023]
Abstract
Background Type 2 diabetes, obesity and insulin resistance are characterized by hypertriglyceridemia and ectopic accumulation of lipids in liver and skeletal muscle. AGPAT6 encodes a novel glycerol-3 phosphate acyltransferase, GPAT4, which catalyzes the first step in the de novo triglyceride synthesis. AGPAT6-deficient mice show lower weight and resistance to diet- and genetically induced obesity. Here, we examined whether common or low-frequency variants in AGPAT6 associate with type 2 diabetes or related metabolic traits in a Danish population. Methods Eleven variants selected by a candidate gene approach capturing the common and low-frequency variation of AGPAT6 were genotyped in 12,068 Danes from four study populations of middle-aged individuals. The case–control study involved 4,638 type 2 diabetic and 5,934 glucose-tolerant individuals, while studies of quantitative metabolic traits were performed in 5,645 non-diabetic participants of the Inter99 Study. Results None of the eleven AGPAT6 variants were robustly associated with type 2 diabetes in the Danish case–control study. Moreover, none of the AGPAT6 variants showed association with measures of obesity (waist circumference and BMI), serum lipid concentrations, fasting or 2-h post-glucose load levels of plasma glucose and serum insulin, or estimated indices of insulin secretion or insulin sensitivity. Conclusions Common and low-frequency variants in AGPAT6 do not significantly associate with type 2 diabetes susceptibility, or influence related phenotypic traits such as obesity, dyslipidemia or indices of insulin sensitivity or insulin secretion in the population studied.
Collapse
|
84
|
Koliaki C, Roden M. Hepatic energy metabolism in human diabetes mellitus, obesity and non-alcoholic fatty liver disease. Mol Cell Endocrinol 2013; 379:35-42. [PMID: 23770462 DOI: 10.1016/j.mce.2013.06.002] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Revised: 05/08/2013] [Accepted: 06/03/2013] [Indexed: 12/13/2022]
Abstract
Alterations of hepatic mitochondrial function have been observed in states of insulin resistance and non-alcoholic fatty liver disease (NAFLD). Patients with overt type 2 diabetes mellitus (T2DM) can exhibit reduction in hepatic adenosine triphosphate (ATP) synthesis and impaired repletion of their hepatic ATP stores upon ATP depletion by fructose. Obesity and NAFLD may also associate with impaired ATP recovery after ATP-depleting challenges and augmented oxidative stress in the liver. On the other hand, patients with obesity or NAFLD can present with upregulated hepatic anaplerotic and oxidative fluxes, including β-oxidation and tricarboxylic cycle activity. The present review focuses on the methods and data on hepatic energy metabolism in various states of human insulin resistance. We propose that the liver can adapt to increased lipid exposition by greater lipid storing and oxidative capacity, resulting in increased oxidative stress, which in turn could deteriorate hepatic mitochondrial function in chronic insulin resistance and NAFLD.
Collapse
Affiliation(s)
- Chrysi Koliaki
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Düsseldorf, Germany.
| | | |
Collapse
|
85
|
Hong HC, Lee JS, Choi HY, Yang SJ, Yoo HJ, Seo JA, Kim SG, Kim NH, Baik SH, Choi DS, Choi KM. Liver enzymes and vitamin D levels in metabolically healthy but obese individuals: Korean National Health and Nutrition Examination Survey. Metabolism 2013; 62:1305-12. [PMID: 23643404 DOI: 10.1016/j.metabol.2013.04.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2012] [Revised: 03/22/2013] [Accepted: 04/02/2013] [Indexed: 02/06/2023]
Abstract
OBJECTIVE Increased liver enzymes and decreased vitamin D levels are associated with insulin resistance and type 2 diabetes. We examined liver enzymes and vitamin D levels in metabolically healthy but obese (MHO) individuals and compared the values with those of other body size phenotypes in the Korean population. MATERIALS/METHODS A total of 16,190 people over the age of 18years were analyzed using data from the Fourth Korean National Health and Nutrition Examination Survey, which is a nationally representative survey. Body size phenotypes were classified into four groups by body mass index (BMI) and number of metabolic syndrome components. RESULTS The prevalence of MHO was 14.9% in the entire population and 47.7% in the obese population. In a correlation analysis adjusted for age, sex, and BMI, AST and ALT levels were positively correlated with insulin resistance and cardiometabolic risk factors of the metabolic syndrome, whereas vitamin D level was negatively correlated with these variables. MHO individuals had significantly lower concentrations of AST and ALT compared to metabolically abnormal obese (MAO) subjects, although vitamin D levels were not significantly different. Furthermore, a multiple logistic regression analysis revealed that MHO individuals had lower risk of liver enzyme abnormality compared to MAO after adjusting for potential confounding factors. However, the risk of vitamin D deficiency was not significantly different among groups with different body size phenotypes. CONCLUSIONS Although both liver enzymes and vitamin D levels are related to insulin resistance and metabolic syndrome, only liver enzymes were independently associated with MHO phenotype.
Collapse
Affiliation(s)
- Ho Cheol Hong
- Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, Korea University, Seoul, Korea
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
86
|
Krentz AJ, Viljoen A, Sinclair A. Insulin resistance: a risk marker for disease and disability in the older person. Diabet Med 2013; 30:535-48. [PMID: 23173973 DOI: 10.1111/dme.12063] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Accepted: 11/06/2012] [Indexed: 12/24/2022]
Abstract
Clinical metabolic studies have demonstrated that insulin action declines progressively with age in humans. In addition to its close association with Type 2 diabetes, which reduces life expectancy in older people, age-related insulin resistance is implicated in pathogenesis of several highly prevalent disorders for which ageing is a major risk factor. These include atherosclerotic cardiovascular disease, dementia, frailty and cancer. Accordingly, insulin resistance may be viewed as biomarker of age-related ill health and reduced lifespan. The rapidly rising number of older people, coupled with a high prevalence of insulin resistance resulting from obesity and sedentary lifestyles, presents unprecedented public health and societal challenges. Studies of centenarians have shown that preserved whole-body sensitivity to insulin is associated with longevity. The mechanisms through which insulin action is associated with age-related diseases remain unclear. Changes in body composition, i.e. sarcopenia and excess adiposity, may be more potent than age per se. Moreover, the impact of insulin resistance has been difficult to disentangle from the clustering of vascular risk factors that co-segregate with the insulin resistance-hyperinsulinaemia complex. Potentially modifiable mediators of age-related changes in insulin sensitivity include alterations in adipocytokines, impaired skeletal myocyte mitochondrial function and brown fat activity. The hypothesis that improving or maintaining insulin sensitivity preserves health and extends lifespan merits further evaluation. Practical non-pharmacological interventions directed against age-related insulin resistance remain underdeveloped. Novel metabolically active pharmacological agents with theoretical implications for some age-related disorders are entering clinical trials. However, recent adverse experiences with the thiazolidinediones suggest the need for a cautious approach to the use of insulin sensitizing drugs in older people. This could be particularly important in the absence of diabetes where the risk to benefit analysis may be less favourable.
Collapse
Affiliation(s)
- A J Krentz
- Institute of Diabetes for Older People, Bedfordshire & Hertfordshire Postgraduate Medical School, University of Bedfordshire, Luton, UK.
| | | | | |
Collapse
|
87
|
Wu D, Ren Z, Pae M, Han SN, Meydani SN. Diet-induced obesity has a differential effect on adipose tissue and macrophage inflammatory responses of young and old mice. Biofactors 2013; 39:326-33. [PMID: 23345024 DOI: 10.1002/biof.1075] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Accepted: 11/12/2012] [Indexed: 01/01/2023]
Abstract
Obesity and aging are both associated with increased inflammation in adipose tissue. In this study, we investigated effect of diet-induced obesity on inflammatory status in young and old mice. Young (2 months) and old (19 months) C57BL/6 mice were fed a low-fat (10%, LF) or high-fat (60%, HF) diet for 4.5 months. Adipose tissue from old/LF mice expressed higher levels of IL-1β, IL-6, TNFα, and cyclooxygenase-2 mRNA compared with young/LF mice. HF diet upregulated expression of all these inflammatory markers in young mice to the levels seen in the aged. Adipocytes, but not stromal vascular cells, from old/LF mice produced more IL-6, TNFα, and prostaglandin (PG)E2 than those from young/LF mice. HF diet resulted in an increase of all these markers produced by adipocytes in young, but only TNFα in old mice. PGE2 produced by peritoneal macrophages (Mϕ's) was upregulated with aging, and HF diet induced more IL-6, TNFα, and PGE2 production in young but not in old mice. Thus, HF diet/obesity induces an inflammatory state in both visceral fat cells and peritoneal Mϕ's of young mice, but not so in old mice. Together, these results suggest that HF diet-induced obesity may speed up the aging process as characterized by inflammatory status. This study also indicates that animals have a differential response, depending on their ages, to HF diet-induced obesity and inflammation. This age-related difference in response to HF diet should be considered when using inflammation status as a marker in investigating adverse health impacts of HF diet and obesity.
Collapse
Affiliation(s)
- Dayong Wu
- Nutritional Immunology Laboratory, JM USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111, USA.
| | | | | | | | | |
Collapse
|
88
|
Tsatsoulis A, Mantzaris MD, Bellou S, Andrikoula M. Insulin resistance: an adaptive mechanism becomes maladaptive in the current environment - an evolutionary perspective. Metabolism 2013; 62:622-33. [PMID: 23260798 DOI: 10.1016/j.metabol.2012.11.004] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Revised: 11/08/2012] [Accepted: 11/14/2012] [Indexed: 01/07/2023]
Abstract
Human survival has relied upon the ability to withstand starvation through energy storage, the capacity to fight off infection by a proinflammatory immune response, and the ability to cope with physical stressors by an adaptive stress response. Energy storage, mainly as glycogen in liver and triglycerides in adipose tissue, is regulated by the anabolic actions of insulin. On the other hand, mobilization of stored energy during infection, trauma or stress is served by the temporary inhibition of insulin action (insulin resistance) in target tissues by proinflammatory cytokines and stress hormones. In the current environment, high energy intake, low physical activity, and chronic stress favor the storage of surplus fat in adipose tissue depots that far exceeds their storage capacity and liporegulation. Lipid overload in central fat depots initiates an inflammatory response and adipocyte dysfunction with resultant low-grade systemic inflammation and lipid overflow to peripheral tissues. In turn, proinflammatory cytokines and non-oxidized lipid metabolites, accumulated in liver and muscle cells, activate the mechanism of insulin resistance as would occur in the case of infection or stress. The same factors together with the ensuing insulin resistance further contribute to pancreatic β-cell dysfunction and ultimately to type 2 diabetes and cardiovascular disease. The present review supports the hypothesis that insulin resistance evolved as a physiological adaptive mechanism in human survival and that the same mechanism is inappropriately activated on a chronic basis in the current environment, leading to the manifestations of the metabolic syndrome.
Collapse
Affiliation(s)
- Agathocles Tsatsoulis
- Department of Endocrinology, Medical School, University of Ioannina, 45110 Ioannina, Greece.
| | | | | | | |
Collapse
|
89
|
Ishigaki Y, Katagiri H. [Diabetes mellitus related common medical disorders: recent progress in diagnosis and treatment. Topics: I. Pathophysiology, diagnosis and treatment; 10. Obesity-related disorders]. NIHON NAIKA GAKKAI ZASSHI. THE JOURNAL OF THE JAPANESE SOCIETY OF INTERNAL MEDICINE 2013; 102:895-901. [PMID: 23772504 DOI: 10.2169/naika.102.895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Affiliation(s)
- Yasushi Ishigaki
- Department of Diabetes and Metabolism, Tohoku University Hospital, Japan
| | | |
Collapse
|
90
|
Carstensen M, Herder C, Kempf K, Erlund I, Martin S, Koenig W, Sundvall J, Bidel S, Kuha S, Roden M, Tuomilehto J. Sfrp5 correlates with insulin resistance and oxidative stress. Eur J Clin Invest 2013; 43:350-7. [PMID: 23398169 DOI: 10.1111/eci.12052] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Accepted: 01/10/2013] [Indexed: 01/04/2023]
Abstract
BACKGROUND Secreted frizzled-related protein 5 (Sfrp5) has been described as novel adipokine in mice with insulin-sensitising and anti-inflammatory properties similar to adiponectin. The aim of this study was to compare serum concentrations and determinants of Sfrp5, its pro-inflammatory antagonist wingless-type MMTV integration site family member (Wnt)5a and adiponectin in humans and their regulation by coffee. MATERIAL AND METHODS Serum concentrations of Sfrp5, Wnt5a and adiponectin were measured in 47 individuals who participated in a coffee intervention study. Associations with demographic, metabolic and immunological variables and regulation of serum levels by different amounts of daily coffee intake were analysed. RESULTS At baseline, fasting serum Sfrp5 levels ranged between 96 and 4056 ng/mL. Sfrp5 was directly correlated with a surrogate of insulin resistance (homeostasis model assessment of insulin resistance/HOMA-IR; r = 0·32, P < 0·05) and with the oxidative stress markers 8-isoprostane (r = 0·44, P < 0·01) and nitrotyrosine (r = 0·52, P < 0·001). Adiponectin showed inverse correlations with several indices of insulin resistance (e.g. HOMA-IR, Stumvoll index; all P < 0·05) and a direct correlation with the anti-atherogenic apolipoprotein A-I (r = 0·56, P < 0·001). Coffee did not affect serum concentrations of Sfrp5. Serum Wnt5a concentrations were below the detection limit (0·02 ng/mL) in 81% of the study participants. CONCLUSIONS In contrast to obese mouse models, serum Sfrp5 was directly related to HOMA-IR and oxidative stress in humans, but not with apolipoproteins, and thus, associations differed from those found for circulating adiponectin. These differences between Sfrp5 and adiponectin might be explained by differences in the investigated species.
Collapse
Affiliation(s)
- Maren Carstensen
- Institute for Clinical Diabetology, German Diabetes Center, Düsseldorf, Germany
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
91
|
Granér M, Siren R, Nyman K, Lundbom J, Hakkarainen A, Pentikäinen MO, Lauerma K, Lundbom N, Adiels M, Nieminen MS, Taskinen MR. Cardiac steatosis associates with visceral obesity in nondiabetic obese men. J Clin Endocrinol Metab 2013; 98:1189-97. [PMID: 23418318 DOI: 10.1210/jc.2012-3190] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND Liver fat and visceral adiposity are involved in the development of the metabolic syndrome (MetS). Ectopic fat accumulation within and around the heart has been related to increased risk of heart disease. The aim of this study was to explore components of cardiac steatosis and their relationship to intra-abdominal ectopic fat deposits and cardiometabolic risk factors in nondiabetic obese men. METHODS Myocardial and hepatic triglyceride (TG) contents were measured with 1.5 T magnetic resonance spectroscopy, and visceral adipose (VAT), abdominal subcutaneous tissue (SAT), epicardial and pericardial fat by magnetic resonance imaging in 37 men with the MetS and in 40 men without the MetS. RESULTS Myocardial and hepatic TG contents, VAT, SAT, epicardial fat volumes, and pericardial fat volumes were higher in men with the MetS compared with subjects without the MetS (P < .001). All components of cardiac steatosis correlated with SAT, VAT, and hepatic TG content and the correlations seemed to be strongest with VAT. Myocardial TG content, epicardial fat, pericardial fat, VAT, and hepatic TG content correlated with waist circumference, body mass index, high-density lipoprotein cholesterol TGs, very low-density lipoprotein-1 TGs, and the insulin-resistance homeostasis model assessment index. VAT was a predictor of TGs, high-density lipoprotein cholesterol, and measures of glucose metabolism, whereas age and SAT were determinants of blood pressure parameters. CONCLUSIONS We suggest that visceral obesity is the best predictor of epicardial and pericardial fat in abdominally obese subjects. Myocardial TG content may present a separate entity that is influenced by factors beyond visceral adiposity.
Collapse
Affiliation(s)
- Marit Granér
- Department of Medicine, Division of Cardiology, Helsinki University Central Hospital, Haartmaninkatu 4, FIN-00290 HUCH, Finland.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
92
|
Abstract
PURPOSE OF REVIEW To evaluate the relationship between cardiac fat accumulation and insulin resistance. We discuss the current knowledge regarding the different techniques for measuring, in vivo in humans, cardiac fat deposition, the effects of systemic and myocardial insulin resistance and the clinical relevance of the relation between atherosclerosis and cardiac fat in conditions of insulin resistance. RECENT FINDINGS In humans, fat accumulates mainly around the heart, as epicardial, perivascular and intrathoracic fat, but also inside the cardiomyocytes. All these cardiac fat depots have been shown to be markers of cardiac lipotoxicity, mitochondrial dysfunction, inflammation and local and systemic insulin resistance as well as of atherosclerosis and cardiac dysfunction. SUMMARY Although cardiac fat is associated with impairment in heart metabolism and cardiac dysfunction, the interplay among cardiac fat accumulation, insulin resistance and cardiac dysfunction remains to be fully established.
Collapse
Affiliation(s)
- Amalia Gastaldelli
- Institute of Clinical Physiology, National Research Council, Pisa, Italy
| | | | | | | |
Collapse
|
93
|
Berglund L, Brunzell JD, Goldberg AC, Goldberg IJ, Sacks F, Murad MH, Stalenhoef AFH. Evaluation and treatment of hypertriglyceridemia: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab 2012; 97:2969-89. [PMID: 22962670 PMCID: PMC3431581 DOI: 10.1210/jc.2011-3213] [Citation(s) in RCA: 534] [Impact Index Per Article: 44.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
OBJECTIVE The aim was to develop clinical practice guidelines on hypertriglyceridemia. PARTICIPANTS The Task Force included a chair selected by The Endocrine Society Clinical Guidelines Subcommittee (CGS), five additional experts in the field, and a methodologist. The authors received no corporate funding or remuneration. CONSENSUS PROCESS Consensus was guided by systematic reviews of evidence, e-mail discussion, conference calls, and one in-person meeting. The guidelines were reviewed and approved sequentially by The Endocrine Society's CGS and Clinical Affairs Core Committee, members responding to a web posting, and The Endocrine Society Council. At each stage, the Task Force incorporated changes in response to written comments. CONCLUSIONS The Task Force recommends that the diagnosis of hypertriglyceridemia be based on fasting levels, that mild and moderate hypertriglyceridemia (triglycerides of 150-999 mg/dl) be diagnosed to aid in the evaluation of cardiovascular risk, and that severe and very severe hypertriglyceridemia (triglycerides of > 1000 mg/dl) be considered a risk for pancreatitis. The Task Force also recommends that patients with hypertriglyceridemia be evaluated for secondary causes of hyperlipidemia and that subjects with primary hypertriglyceridemia be evaluated for family history of dyslipidemia and cardiovascular disease. The Task Force recommends that the treatment goal in patients with moderate hypertriglyceridemia be a non-high-density lipoprotein cholesterol level in agreement with National Cholesterol Education Program Adult Treatment Panel guidelines. The initial treatment should be lifestyle therapy; a combination of diet modification and drug therapy may also be considered. In patients with severe or very severe hypertriglyceridemia, a fibrate should be used as a first-line agent.
Collapse
Affiliation(s)
- Lars Berglund
- University of California, Davis, Sacramento, California 95817, USA
| | | | | | | | | | | | | | | |
Collapse
|
94
|
Wronska A, Kmiec Z. Structural and biochemical characteristics of various white adipose tissue depots. Acta Physiol (Oxf) 2012; 205:194-208. [PMID: 22226221 DOI: 10.1111/j.1748-1716.2012.02409.x] [Citation(s) in RCA: 240] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Revised: 09/29/2011] [Accepted: 01/02/2012] [Indexed: 12/11/2022]
Abstract
It is now widely accepted that white adipose tissue (WAT) is not merely a fuel storage organ, but also a key component of metabolic homoeostatic mechanisms. Apart from its major role in lipid and glucose metabolism, adipose tissue is also involved in a wide array of other biological processes. The hormones and adipokines, as well as other biologically active agents released from fat cells, affect many physiological and pathological processes. WAT is neither uniform nor inflexible because it undergoes constant remodelling, adapting the size and number of adipocytes to changes in nutrients' availability and hormonal milieu. Fat depots from different areas of the body display distinct structural and functional properties and have disparate roles in pathology. The two major types of WAT are visceral fat, localized within the abdominal cavity and mediastinum, and subcutaneous fat in the hypodermis. Visceral obesity correlates with increased risk of insulin resistance and cardiovascular diseases, while increase of subcutaneous fat is associated with favourable plasma lipid profiles. Visceral adipocytes show higher lipogenic and lipolytic activities and produce more pro-inflammatory cytokines, while subcutaneous adipocytes are the main source of leptin and adiponectin. Moreover, adipose tissue associated with skeletal muscles (intramyocellular and intermuscular fat) and with the epicardium is believed to provide fuels for skeletal and cardiac muscle contraction. However, increased mass of either epicardial or intermuscular adipose tissue correlates with cardiovascular risk, while the presence of the intramyocellular fat is a risk factor for the development of insulin resistance. This review summarizes results of mainly human studies related to the differential characteristics of various WAT depots.
Collapse
Affiliation(s)
- A. Wronska
- Department of Histology; Medical Faculty; Medical University of Gdansk; Gdansk; Poland
| | - Z. Kmiec
- Department of Histology; Medical Faculty; Medical University of Gdansk; Gdansk; Poland
| |
Collapse
|
95
|
Kishida K, Funahashi T, Matsuzawa Y, Shimomura I. Visceral adiposity as a target for the management of the metabolic syndrome. Ann Med 2012; 44:233-41. [PMID: 21612331 DOI: 10.3109/07853890.2011.564202] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Atherosclerosis, the underlying cause of atherosclerotic cardiovascular disease (ACVD), develops due not only to a single cardiovascular risk factor but to a variety of complex factors. The concept of the multiple cardiometabolic risk factor clustering syndrome has been proposed as a highly atherogenic state, independent of hypercholesterolemia and smoking. Body fat distribution, especially visceral fat accumulation, is a major correlate of a cluster of diabetogenic, atherogenic, prothrombotic, and proinflammatory metabolic abnormalities referred to as the metabolic syndrome, with dysfunctional adipocytes and dysregulated production of adipocytokines (hypoadiponectinemia). Medical research has focused on visceral adiposity as an important component of the syndrome in Japanese subjects with a mild degree of adiposity compared with Western subjects. For the prevention of ACVD at least in Japan, it might be practical to stratify subjects with multiple risk factors for atherosclerotic cardiovascular disease based on visceral fat accumulation. Visceral fat reduction through health promotion programs using risk factor-oriented approaches may be effective in reducing ACVD events, as well as producing improvement in risks and hypoadiponectinemia. This review article discusses visceral adiposity as a key player in the syndrome. Visceral fat reduction with life-style modification is a potentially useful strategy in the prevention of ACVD in patients with the metabolic syndrome.
Collapse
Affiliation(s)
- Ken Kishida
- Department of Metabolic Medicine, Graduate School of Medicine, Osaka University, Japan.
| | | | | | | |
Collapse
|
96
|
Sironi AM, Petz R, De Marchi D, Buzzigoli E, Ciociaro D, Positano V, Lombardi M, Ferrannini E, Gastaldelli A. Impact of increased visceral and cardiac fat on cardiometabolic risk and disease. Diabet Med 2012; 29:622-7. [PMID: 22023514 DOI: 10.1111/j.1464-5491.2011.03503.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE Previous studies have highlighted the associations between abdominal, cardiac or total fat accumulation and cardiovascular disease. The aim of this study was to investigate the impact of different ectopic fat depots on measurements of metabolic dysfunction and cardiovascular disease risk. METHODS Using magnetic resonance imaging in 113 subjects, we measured abdominal (visceral and subcutaneous) and cardiac (epicardial and extra-pericardial) fat depots and examined their association with overall (BMI) and abdominal obesity (waist circumference), dyslipidaemia (triglycerides, total and HDL cholesterol), glucose tolerance (by an oral glucose tolerance test) and insulin sensitivity, blood pressure and 10-year coronary heart disease risk by Framingham score. RESULTS Fat accumulation was proportional to the degree of obesity, with body fat ranging from 14 to 33 kg, visceral fat from 0.8 to 1.8 kg and cardiac fat from 134 to 236 g. Most cardiac fat (70% on average) was extra-pericardial, with a wide variability for both cardiac depots (epicardial: 172-2008 mm(2); extra-pericardial: 100-5056 mm(2)). Only visceral and extra-pericardial fat, but not epicardial or subcutaneous fat, could discriminate between subjects with three or more factors of the metabolic syndrome or medium-to-high coronary heart disease risk score. Controlling for gender and BMI by multivariable analysis, the best marker of reduced insulin sensitivity was visceral fat (partial r = -0.35); extra-pericardial fat was the closest associate of increased blood pressure (partial r = 0.26) and both extra-pericardial and visceral fat clustered with hypertriglyceridaemia (partial r = 0.29 and 0.24; both P < 0.02). CONCLUSION Increased epicardial fat per se does not necessarily translate into presence or prediction of disease. In contrast, increased deposition of visceral abdominal and extra-pericardial mediastinal fat are both associated with an enhanced cardiovascular disease risk profile.
Collapse
Affiliation(s)
- A M Sironi
- Dipartimento di Medicina Interna, National Research Council Institute of Clinical Physiology, Pisa, Italy
| | | | | | | | | | | | | | | | | |
Collapse
|
97
|
Maris M, Overbergh L, Gysemans C, Waget A, Cardozo AK, Verdrengh E, Cunha JPM, Gotoh T, Cnop M, Eizirik DL, Burcelin R, Mathieu C. Deletion of C/EBP homologous protein (Chop) in C57Bl/6 mice dissociates obesity from insulin resistance. Diabetologia 2012; 55:1167-78. [PMID: 22237685 DOI: 10.1007/s00125-011-2427-7] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2011] [Accepted: 11/29/2011] [Indexed: 01/23/2023]
Abstract
AIMS/HYPOTHESIS Endoplasmic reticulum (ER) stress has been implicated in the development of type 2 diabetes, via effects on obesity, insulin resistance and pancreatic beta cell health. C/EBP homologous protein (CHOP) is induced by ER stress and has a central role in apoptotic execution pathways triggered by ER stress. The aim of this study was to characterise the role of CHOP in obesity and insulin resistance. METHODS Metabolic studies were performed in Chop ( -/- ) and wild-type C57Bl/6 mice, and included euglycaemic-hyperinsulinaemic clamps and indirect calorimetry. The inflammatory state of liver and adipose tissue was determined by quantitative RT-PCR, immunohistology and macrophage cultures. Viability and absence of ER stress in islets of Langerhans was determined by electron microscopy, islet culture and quantitative RT-PCR. RESULTS Systemic deletion of Chop induced abdominal obesity and hepatic steatosis. Despite marked obesity, Chop ( -/- ) mice had preserved normal glucose tolerance and insulin sensitivity. This discrepancy was accompanied by lower levels of pro-inflammatory cytokines and less infiltration of immune cells into fat and liver. CONCLUSIONS/INTERPRETATION These observations suggest that insulin resistance is not induced by fat accumulation per se, but rather by the inflammation induced by ectopic fat. CHOP may play a key role in the crosstalk between excessive fat deposition and induction of inflammation-mediated insulin resistance.
Collapse
Affiliation(s)
- M Maris
- Catholic University of Leuven, Leuven, Belgium
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
98
|
Kase ET, Nikolić N, Hessvik NP, Fjeldheim ÅK, Jensen J, Thoresen GH, Rustan AC. Dietary Supplementation with 22-S-Hydroxycholesterol to Rats Reduces Body Weight Gain and the Accumulation of Liver Triacylglycerol. Lipids 2012; 47:483-93. [DOI: 10.1007/s11745-012-3663-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Accepted: 02/29/2012] [Indexed: 01/08/2023]
|
99
|
Complete failure of insulin-transmitted signaling, but not obesity-induced insulin resistance, impairs respiratory chain function in muscle. J Mol Med (Berl) 2012; 90:1145-60. [DOI: 10.1007/s00109-012-0887-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Revised: 02/09/2012] [Accepted: 02/21/2012] [Indexed: 01/22/2023]
|
100
|
Qi Q, Liang L, Doria A, Hu FB, Qi L. Genetic predisposition to dyslipidemia and type 2 diabetes risk in two prospective cohorts. Diabetes 2012; 61:745-52. [PMID: 22315312 PMCID: PMC3282815 DOI: 10.2337/db11-1254] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Dyslipidemia has been associated with type 2 diabetes, but it remains unclear whether dyslipidemia plays a causal role in type 2 diabetes. We aimed to examine the association between the genetic predisposition to dyslipdemia and type 2 diabetes risk. The current study included 2,447 patients with type 2 diabetes and 3,052 control participants of European ancestry from the Nurses' Health Study and the Health Professionals Follow-up Study. Genetic predisposition to dyslipidemia was estimated by three genotype scores of lipids (LDL cholesterol, HDL cholesterol, and triglycerides) on the basis of the established loci for blood lipids. Linear relation analysis indicated that the HDL cholesterol and triglyceride genotype scores, but not the LDL cholesterol genotype score, were linearly related to elevated type 2 diabetes risk. Each point of the HDL cholesterol and triglyceride genotype scores was associated with a 3% (odds ratio [OR] 1.03 [95% CI 1.01-1.04]) and a 2% (1.02 [1.00-1.04]) increased risk of developing type 2 diabetes, respectively. The ORs were 1.39 (1.17-1.65) and 1.19 (1.01-1.41) for type 2 diabetes by comparing extreme quartiles of the HDL cholesterol genotype score and triglyceride genotype score, respectively. In conclusion, genetic predisposition to low HDL cholesterol or high triglycerides is related to elevated type 2 diabetes risk.
Collapse
Affiliation(s)
- Qibin Qi
- Department of Nutrition, Harvard School of Public Health, Boston, Massachusetts
| | - Liming Liang
- Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts
| | - Alessandro Doria
- Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts
- Department of Medicine, Harvard Medical School, Boston, Massachusetts
| | - Frank B. Hu
- Department of Nutrition, Harvard School of Public Health, Boston, Massachusetts
- Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts
- Channing Laboratory, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
| | - Lu Qi
- Department of Nutrition, Harvard School of Public Health, Boston, Massachusetts
- Channing Laboratory, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
- Corresponding author: Lu Qi,
| |
Collapse
|