1401
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Abstract
The fields of immunology and metabolism are rapidly converging on adipose tissue. During obesity, many immune cells infiltrate or populate in adipose tissue and promote a low-grade chronic inflammation. Studies to date have suggested that perturbation of inflammation is critically linked to nutrient metabolic pathways and to obesity-associated complications such as insulin resistance and type 2 diabetes. Despite these advances, however, many open questions remain including how inflammatory responses are initiated and maintained, how nutrients impact the function of various immune populations, and how inflammatory responses affect systemic insulin sensitivity. Here we review recent studies on the roles of various immune cells at different phases of obesity and discuss molecular mechanisms underlying obesity-associated inflammation. Better understanding of the events occurring in adipose tissue will provide insights into the pathophysiological role of inflammation in obesity and shed light on the pathogenesis of obesity-associated metabolic syndrome.
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Affiliation(s)
- Shengyi Sun
- Graduate Program in Biochemistry, Molecular and Cell Biology, Cornell University, Ithaca, New York 14853, USA
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1402
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Wolf D, Jehle F, Ortiz Rodriguez A, Dufner B, Hoppe N, Colberg C, Lozhkin A, Bassler N, Rupprecht B, Wiedemann A, Hilgendorf I, Stachon P, Willecke F, Febbraio M, Binder CJ, Bode C, Zirlik A, Peter K. CD40L deficiency attenuates diet-induced adipose tissue inflammation by impairing immune cell accumulation and production of pathogenic IgG-antibodies. PLoS One 2012; 7:e33026. [PMID: 22412980 PMCID: PMC3297623 DOI: 10.1371/journal.pone.0033026] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Accepted: 02/09/2012] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Adipose tissue inflammation fuels the metabolic syndrome. We recently reported that CD40L--an established marker and mediator of cardiovascular disease--induces inflammatory cytokine production in adipose cells in vitro. Here, we tested the hypothesis that CD40L deficiency modulates adipose tissue inflammation in vivo. METHODOLOGY/PRINCIPAL FINDINGS WT or CD40L(-/-) mice consumed a high fat diet (HFD) for 20 weeks. Inflammatory cell recruitment was impaired in mice lacking CD40L as shown by a decrease of adipose tissue macrophages, B-cells, and an increase in protective T-regulatory cells. Mechanistically, CD40L-deficient mice expressed significantly lower levels of the pro-inflammatory chemokine MCP-1 both, locally in adipose tissue and systemically in plasma. Moreover, levels of pro-inflammatory IgG-antibodies against oxidized lipids were reduced in CD40L(-/-) mice. Also, circulating low-density lipoproteins and insulin levels were lower in CD40L(-/-) mice. However, CD40L(-/-) mice consuming HFD were not protected from the onset of diet-induced obesity (DIO), insulin resistance, and hepatic steatosis, suggesting that CD40L selectively limits the inflammatory features of diet-induced obesity rather than its metabolic phenotype. Interestingly, CD40L(-/-) mice consuming a low fat diet (LFD) showed both, a favorable inflammatory and metabolic phenotype characterized by diminished weight gain, improved insulin tolerance, and attenuated plasma adipokine levels. CONCLUSION We present the novel finding that CD40L deficiency limits adipose tissue inflammation in vivo. These findings identify CD40L as a potential mediator at the interface of cardiovascular and metabolic disease.
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Affiliation(s)
- Dennis Wolf
- Atherogenesis Research Group, Department of Cardiology, University of Freiburg, Freiburg, Germany
| | - Felix Jehle
- Atherogenesis Research Group, Department of Cardiology, University of Freiburg, Freiburg, Germany
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | | | - Bianca Dufner
- Atherogenesis Research Group, Department of Cardiology, University of Freiburg, Freiburg, Germany
| | - Natalie Hoppe
- Atherogenesis Research Group, Department of Cardiology, University of Freiburg, Freiburg, Germany
| | - Christian Colberg
- Atherogenesis Research Group, Department of Cardiology, University of Freiburg, Freiburg, Germany
| | - Andrey Lozhkin
- Atherogenesis Research Group, Department of Cardiology, University of Freiburg, Freiburg, Germany
| | - Nicole Bassler
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Benjamin Rupprecht
- Atherogenesis Research Group, Department of Cardiology, University of Freiburg, Freiburg, Germany
| | - Ansgar Wiedemann
- Atherogenesis Research Group, Department of Cardiology, University of Freiburg, Freiburg, Germany
| | - Ingo Hilgendorf
- Atherogenesis Research Group, Department of Cardiology, University of Freiburg, Freiburg, Germany
| | - Peter Stachon
- Atherogenesis Research Group, Department of Cardiology, University of Freiburg, Freiburg, Germany
| | - Florian Willecke
- Atherogenesis Research Group, Department of Cardiology, University of Freiburg, Freiburg, Germany
| | - Mark Febbraio
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Christoph J. Binder
- Department of Laboratory Medicine, Medical University of Vienna and Center for Molecular Medicine, Austrian Academy of Sciences, Vienna, Austria
| | - Christoph Bode
- Atherogenesis Research Group, Department of Cardiology, University of Freiburg, Freiburg, Germany
| | - Andreas Zirlik
- Atherogenesis Research Group, Department of Cardiology, University of Freiburg, Freiburg, Germany
| | - Karlheinz Peter
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
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1403
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Osborn O, Olefsky JM. The cellular and signaling networks linking the immune system and metabolism in disease. Nat Med 2012; 18:363-74. [PMID: 22395709 DOI: 10.1038/nm.2627] [Citation(s) in RCA: 1112] [Impact Index Per Article: 92.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
It is now recognized that obesity is driving the type 2 diabetes epidemic in Western countries. Obesity-associated chronic tissue inflammation is a key contributing factor to type 2 diabetes and cardiovascular disease, and a number of studies have clearly demonstrated that the immune system and metabolism are highly integrated. Recent advances in deciphering the various cellular and signaling networks that participate in linking the immune and metabolic systems together have contributed to understanding of the pathogenesis of metabolic diseases and may also inform new therapeutic strategies based on immunomodulation. Here we discuss how these various networks underlie the etiology of the inflammatory component of insulin resistance, with a particular focus on the central roles of macrophages in adipose tissue and liver.
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Affiliation(s)
- Olivia Osborn
- Department of Medicine, Division of Endocrinology and Metabolism, University of California-San Diego, La Jolla, California, USA
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1404
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Ji Y, Sun S, Xu A, Bhargava P, Yang L, Lam KSL, Gao B, Lee CH, Kersten S, Qi L. Activation of natural killer T cells promotes M2 Macrophage polarization in adipose tissue and improves systemic glucose tolerance via interleukin-4 (IL-4)/STAT6 protein signaling axis in obesity. J Biol Chem 2012; 287:13561-71. [PMID: 22396530 DOI: 10.1074/jbc.m112.350066] [Citation(s) in RCA: 160] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Natural killer T (NKT) cells are important therapeutic targets in various disease models and are under clinical trials for cancer patients. However, their function in obesity and type 2 diabetes remains unclear. Our data show that adipose tissues of both mice and humans contain a population of type 1 NKT cells, whose abundance decreases with increased adiposity and insulin resistance. Although loss-of-function of NKT cells had no effect on glucose tolerance in animals with prolonged high fat diet feeding, activation of NKT cells by lipid agonist α-galactosylceramide enhances alternative macrophage polarization in adipose tissue and improves glucose homeostasis in animals at different stages of obesity. Furthermore, the effect of NKT cells is largely mediated by the IL-4/STAT6 signaling axis in obese adipose tissue. Thus, our data identify a novel therapeutic target for the treatment of obesity-associated inflammation and type 2 diabetes.
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Affiliation(s)
- Yewei Ji
- Division of Nutritional Sciences, Cornell University, Ithaca, New York 14853, USA
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1405
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Wouters K, Cudejko C, Gijbels MJJ, Fuentes L, Bantubungi K, Vanhoutte J, Dièvart R, Paquet C, Bouchaert E, Hannou SA, Gizard F, Tailleux A, de Winther MPJ, Staels B, Paumelle R. Bone marrow p16INK4a-deficiency does not modulate obesity, glucose homeostasis or atherosclerosis development. PLoS One 2012; 7:e32440. [PMID: 22403661 PMCID: PMC3293804 DOI: 10.1371/journal.pone.0032440] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2011] [Accepted: 01/31/2012] [Indexed: 12/31/2022] Open
Abstract
Objective A genomic region near the CDKN2A locus, encoding p16INK4a, has been associated to type 2 diabetes and atherosclerotic vascular disease, conditions in which inflammation plays an important role. Recently, we found that deficiency of p16INK4a results in decreased inflammatory signaling in murine macrophages and that p16INK4a influences the phenotype of human adipose tissue macrophages. Therefore, we investigated the influence of immune cell p16INK4a on glucose tolerance and atherosclerosis in mice. Methods and Results Bone marrow p16INK4a-deficiency in C57Bl6 mice did not influence high fat diet-induced obesity nor plasma glucose and lipid levels. Glucose tolerance tests showed no alterations in high fat diet-induced glucose intolerance. While bone marrow p16INK4a-deficiency did not affect the gene expression profile of adipose tissue, hepatic expression of the alternative markers Chi3l3, Mgl2 and IL10 was increased and the induction of pro-inflammatory Nos2 was restrained on the high fat diet. Bone marrow p16INK4a-deficiency in low density lipoprotein receptor-deficient mice did not affect western diet-induced atherosclerotic plaque size or morphology. In line, plasma lipid levels remained unaffected and p16INK4a-deficient macrophages displayed equal cholesterol uptake and efflux compared to wild type macrophages. Conclusion Bone marrow p16INK4a-deficiency does not affect plasma lipids, obesity, glucose tolerance or atherosclerosis in mice.
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Affiliation(s)
- Kristiaan Wouters
- Univ Lille Nord de France, Lille, France
- Inserm, U1011, Lille, France
- Université Droit et Santé de Lille, Lille, France
- Institut Pasteur de Lille, Lille, France
| | - Céline Cudejko
- Univ Lille Nord de France, Lille, France
- Inserm, U1011, Lille, France
- Université Droit et Santé de Lille, Lille, France
- Institut Pasteur de Lille, Lille, France
| | - Marion J. J. Gijbels
- Departments of Molecular Genetics and Pathology, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands
| | - Lucia Fuentes
- Univ Lille Nord de France, Lille, France
- Inserm, U1011, Lille, France
- Université Droit et Santé de Lille, Lille, France
- Institut Pasteur de Lille, Lille, France
| | - Kadiombo Bantubungi
- Univ Lille Nord de France, Lille, France
- Inserm, U1011, Lille, France
- Université Droit et Santé de Lille, Lille, France
- Institut Pasteur de Lille, Lille, France
| | - Jonathan Vanhoutte
- Univ Lille Nord de France, Lille, France
- Inserm, U1011, Lille, France
- Université Droit et Santé de Lille, Lille, France
- Institut Pasteur de Lille, Lille, France
| | - Rebecca Dièvart
- Univ Lille Nord de France, Lille, France
- Inserm, U1011, Lille, France
- Université Droit et Santé de Lille, Lille, France
- Institut Pasteur de Lille, Lille, France
| | - Charlotte Paquet
- Univ Lille Nord de France, Lille, France
- Inserm, U1011, Lille, France
- Université Droit et Santé de Lille, Lille, France
- Institut Pasteur de Lille, Lille, France
| | - Emmanuel Bouchaert
- Univ Lille Nord de France, Lille, France
- Inserm, U1011, Lille, France
- Université Droit et Santé de Lille, Lille, France
- Institut Pasteur de Lille, Lille, France
| | - Sarah Anissa Hannou
- Univ Lille Nord de France, Lille, France
- Inserm, U1011, Lille, France
- Université Droit et Santé de Lille, Lille, France
- Institut Pasteur de Lille, Lille, France
| | - Florence Gizard
- Univ Lille Nord de France, Lille, France
- Inserm, U1011, Lille, France
- Université Droit et Santé de Lille, Lille, France
- Institut Pasteur de Lille, Lille, France
| | - Anne Tailleux
- Univ Lille Nord de France, Lille, France
- Inserm, U1011, Lille, France
- Université Droit et Santé de Lille, Lille, France
- Institut Pasteur de Lille, Lille, France
| | - Menno P. J. de Winther
- Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Bart Staels
- Univ Lille Nord de France, Lille, France
- Inserm, U1011, Lille, France
- Université Droit et Santé de Lille, Lille, France
- Institut Pasteur de Lille, Lille, France
- * E-mail:
| | - Réjane Paumelle
- Univ Lille Nord de France, Lille, France
- Inserm, U1011, Lille, France
- Université Droit et Santé de Lille, Lille, France
- Institut Pasteur de Lille, Lille, France
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1406
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Sun B, Karin M. Obesity, inflammation, and liver cancer. J Hepatol 2012; 56:704-13. [PMID: 22120206 PMCID: PMC3889660 DOI: 10.1016/j.jhep.2011.09.020] [Citation(s) in RCA: 370] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Revised: 08/22/2011] [Accepted: 09/17/2011] [Indexed: 02/07/2023]
Abstract
Obesity has become a universal and major public health problem with increasing prevalence in both adults and children in the 21st century, even in developing countries. Extensive epidemiological studies reveal a strong link between obesity and development and progression of various types of cancers. The connection between obesity and liver cancer is particularly strong and obesity often results in liver diseases such as non-alcoholic fatty liver disease (NAFLD) and the more severe non-alcoholic steatohepatitis (NASH). NASH is characterized by fatty liver inflammation and is believed to cause fibrosis and cirrhosis. The latter is a known liver cancer risk factor. In fact due to its much higher prevalence obesity may be a more substantial contributor to overall hepatocellular carcinoma burden than infection with hepatitis viruses. Here we review and discuss recent advances in elucidation of cellular and molecular alterations and signaling pathways associated with obesity and liver inflammation and their contribution to hepatocarcinogenesis.
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Affiliation(s)
- Beicheng Sun
- Liver Transplantation Center, First Affiliated Hospital and Cancer Center, Nanjing Medical University, Nanjing, Jiangsu Province, PR China.
| | - Michael Karin
- Laboratory of Gene Regulation and Signal Transduction, Department of Pharmacology and Pathology, Cancer Center, UCSD School of Medicine, La Jolla, California 92093-0723, USA
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1407
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Gilbert-Diamond D, Baylin A, Mora-Plazas M, Villamor E. Chronic inflammation is associated with overweight in Colombian school children. Nutr Metab Cardiovasc Dis 2012; 22:244-251. [PMID: 20705440 DOI: 10.1016/j.numecd.2010.06.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2009] [Revised: 03/19/2010] [Accepted: 06/03/2010] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND AIMS To examine the cross-sectional associations of inflammatory markers in plasma including C-reactive protein (CRP) and ferritin, and white blood cell (WBC) count, with overweight, skinfold sum (subscapular + triceps), and skinfold ratio (subscapular/triceps) among children from Bogotá, Colombia. METHODS AND RESULTS The sample (n = 2614) represented low- and middle-income children, aged 5-12 years, from Bogotá. We assessed their anthropometry, sociodemographic characteristics, and circulating inflammatory markers. We defined overweight, including obesity, according to the International Obesity Task Force BMI criteria. After adjustment for potential confounders, children in the fourth quartile of the CRP distribution had a 37% higher prevalence of overweight compared to those in the first quartile (P for trend = 0.03); and children in the fourth quartile of ferritin had a 67% greater prevalence of overweight compared to children in the first quartile (P for trend <0.001). Children in the highest 3 quartiles of the WBC distribution had a 35% higher prevalence of overweight than those in the first quartile (P = 0.03). Ferritin was significantly and positively associated with skinfold sum (P for trend < 0.001), while WBC was significantly and positively associated with skinfold ratio (P for trend < 0.001). There was a significant interaction between CRP and ferritin; children in the highest quartiles of CRP and ferritin had twice the prevalence of overweight compared to those below the highest quartiles (P = 0.001). CONCLUSION Biomarkers of chronic inflammation are positively associated with child overweight. WBC is positively related to skinfold ratio, a proxy for truncal adiposity.
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Affiliation(s)
- D Gilbert-Diamond
- Department of Nutrition, Harvard School of Public Health, Boston, MA 02115, USA
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1408
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Gutierrez DA, Hasty AH. Haematopoietic leptin receptor deficiency does not affect macrophage accumulation in adipose tissue or systemic insulin sensitivity. J Endocrinol 2012; 212:343-51. [PMID: 22194312 PMCID: PMC3381898 DOI: 10.1530/joe-11-0338] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The adipokine leptin is primarily produced by white adipose tissue (AT) and is a potent monocyte/macrophage chemoattractant in vitro. The long form of the leptin receptor (LepR) is required for monocyte/macrophage chemotaxis towards leptin. In this study, we examined the effects of haematopoietic LepR as well as LepR with C-C chemokine receptor 2 (CCR2) deficiency (double knockout (DKO)) on macrophage recruitment to AT after two different periods of high fat diet (HFD) feeding. Briefly, 8-week-old C57BL/6 mice were transplanted with bone marrow (BM) from Lepr(+/+), Lepr(-/-) or DKO donors (groups named BM-Lepr(+/+), BM-Lepr(-/-) and BM-DKO respectively), and were placed on an HFD for 6 or 12 weeks. At the end of the study, macrophage infiltration and the inflammatory state of AT were evaluated by real-time RT-PCR, histology and flow cytometry. In addition, glucose and insulin tolerance were assessed at both time points. Our results showed no differences in macrophage accumulation or AT inflammatory state between the BM-Lepr(+/+) and BM-Lepr(-/-) mice after 6 or 12 weeks of HFD feeding; any effects observed in the BM-DKO were attributed to the haematopoietic deficiency of CCR2. In addition, no changes in glucose or insulin tolerance were observed between groups after either period of HFD feeding. Our findings suggest that although leptin is a potent chemoattractant in vitro, haematopoietic LepR deficiency does not affect macrophage accumulation in AT in early to moderate stages of diet-induced obesity.
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Affiliation(s)
| | - Alyssa H. Hasty
- Corresponding Author Alyssa H. Hasty Room 702 Light Hall, Nashville, TN 37232-0615 Phone: 615-322-5177 Fax: 615-322-8973
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1409
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Satoh M, Andoh Y, Clingan CS, Ogura H, Fujii S, Eshima K, Nakayama T, Taniguchi M, Hirata N, Ishimori N, Tsutsui H, Onoé K, Iwabuchi K. Type II NKT cells stimulate diet-induced obesity by mediating adipose tissue inflammation, steatohepatitis and insulin resistance. PLoS One 2012; 7:e30568. [PMID: 22383967 PMCID: PMC3284453 DOI: 10.1371/journal.pone.0030568] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Accepted: 12/19/2011] [Indexed: 11/18/2022] Open
Abstract
The progression of obesity is accompanied by a chronic inflammatory process that involves both innate and acquired immunity. Natural killer T (NKT) cells recognize lipid antigens and are also distributed in adipose tissue. To examine the involvement of NKT cells in the development of obesity, C57BL/6 mice (wild type; WT), and two NKT-cell-deficient strains, Jα18(-/-) mice that lack the type I subset and CD1d(-/-) mice that lack both the type I and II subsets, were fed a high fat diet (HFD). CD1d(-/-) mice gained the least body weight with the least weight in perigonadal and brown adipose tissue as well as in the liver, compared to WT or Jα18(-/-) mice fed an HFD. Histologically, CD1d(-/-) mice had significantly smaller adipocytes and developed significantly milder hepatosteatosis than WT or Jα18(-/-) mice. The number of NK1.1(+)TCRβ(+) cells in adipose tissue increased when WT mice were fed an HFD and were mostly invariant Vα14Jα18-negative. CD11b(+) macrophages (Mφ) were another major subset of cells in adipose tissue infiltrates, and they were divided into F4/80(high) and F4/80(low) cells. The F4/80(low)-Mφ subset in adipose tissue was increased in CD1d(-/-) mice, and this population likely played an anti-inflammatory role. Glucose intolerance and insulin resistance in CD1d(-/-) mice were not aggravated as in WT or Jα18(-/-) mice fed an HFD, likely due to a lower grade of inflammation and adiposity. Collectively, our findings provide evidence that type II NKT cells initiate inflammation in the liver and adipose tissue and exacerbate the course of obesity that leads to insulin resistance.
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Affiliation(s)
- Masashi Satoh
- Department of Immunology, Kitasato University School of Medicine, Sagamihar, Japan
- Division of Immunobiology, Research Section of Pathophysiology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan
| | - Yasuhiro Andoh
- Division of Immunobiology, Research Section of Pathophysiology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan
- Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Christopher Stuart Clingan
- Division of Immunobiology, Research Section of Pathophysiology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan
- Department of Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Hisako Ogura
- Division of Immunobiology, Research Section of Pathophysiology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan
| | - Satoshi Fujii
- Department of Molecular and Cellular Pathobiology and Therapeutics, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
| | - Koji Eshima
- Department of Immunology, Kitasato University School of Medicine, Sagamihar, Japan
| | - Toshinori Nakayama
- Department of Immunology, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Masaru Taniguchi
- RIKEN Research Center for Allergy and Immunology, Yokohama, Japan
| | - Noriyuki Hirata
- Division of Immunobiology, Research Section of Pathophysiology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan
- Division of Cancer Biology, Research Section of Pathophysiology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan
| | - Naoki Ishimori
- Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Hiroyuki Tsutsui
- Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Kazunori Onoé
- Division of Immunobiology, Research Section of Pathophysiology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan
| | - Kazuya Iwabuchi
- Department of Immunology, Kitasato University School of Medicine, Sagamihar, Japan
- Division of Immunobiology, Research Section of Pathophysiology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan
- * E-mail:
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1410
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Abstract
Macrophages are key innate immune effector cells best known for their role as professional phagocytes, which also include neutrophils and dendritic cells. Recent evidence indicates that macrophages are also key players in metabolic homoeostasis. Macrophages can be found in many tissues, where they respond to metabolic cues and produce pro- and/or anti-inflammatory mediators to modulate metabolite programmes. Certain metabolites, such as fatty acids, ceramides and cholesterol crystals, elicit inflammatory responses through pathogen-sensing signalling pathways, implicating a maladaptation of macrophages and the innate immune system to elevated metabolic stress associated with overnutrition in modern societies. The outcome of this maladaptation is a feedforward inflammatory response leading to a state of unresolved inflammation and a collection of metabolic pathologies, including insulin resistance, fatty liver, atherosclerosis and dyslipidaemia. The present review summarizes what is known about the contributions of macrophages to metabolic diseases and the signalling pathways that are involved in metabolic stress-induced macrophage activation. Understanding the role of macrophages in these processes will help us to develop therapies against detrimental effects of the metabolic syndrome.
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1411
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Goossens GH, Blaak EE, Theunissen R, Duijvestijn AM, Clément K, Tervaert JWC, Thewissen MM. Expression of NLRP3 inflammasome and T cell population markers in adipose tissue are associated with insulin resistance and impaired glucose metabolism in humans. Mol Immunol 2012; 50:142-9. [PMID: 22325453 DOI: 10.1016/j.molimm.2012.01.005] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Revised: 01/11/2012] [Accepted: 01/12/2012] [Indexed: 01/14/2023]
Abstract
Recent studies in rodents indicate that the nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 (NLRP3) inflammasome and a proinflammatory shift in the T cell population in adipose tissue (AT) contribute to AT inflammation and insulin resistance. We investigated: (1) the interplay between the NLRP3 inflammasome and T cell populations in abdominal subcutaneous AT in obese and lean humans in relation to AT inflammatory processes, and (2) involvement of the NLRP3 inflammasome and T cell populations in insulin resistance. Abdominal subcutaneous AT biopsies were collected in 10 obese men with impaired glucose tolerance and 9 lean normal glucose tolerant age-matched controls. AT gene expression of NLRP3 inflammasome-related genes and markers of T cell populations, chemoattraction, macrophage infiltration and other aspects of inflammation were examined. Furthermore, we examined systemic adaptive immune activation and insulin sensitivity (hyperinsulinemic-euglycemic clamp). CASPASE-1 mRNA and the proportion of T(h)1 transcripts (TBX21/CD3ɛ) were significantly higher in AT from obese compared with lean subjects. CASPASE-1 expression and a relative increase in T(h)1 transcripts in AT were strongly associated with insulin resistance and impairments in glucose homeostasis. Gene expression of NLRP3, CASPASE-1, CD3ɛ (pan T cells), TBX21 (T(h)1 cells) and RORC (T(h)17 cells) was positively, whereas GATA3 (T(h)2 cells) was inversely correlated with AT inflammation. Our data suggest that NLRP3 inflammasome activation and a T(h)1 shift in the T cell population in AT of obese subjects is related to insulin resistance and impaired glucose metabolism, which may be explained by AT inflammatory processes.
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Affiliation(s)
- Gijs H Goossens
- Department of Human Biology, NUTRIM School for Nutrition, Toxicology & Metabolism, Maastricht University Medical Centre, Maastricht, The Netherlands.
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1412
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Altintas MM, Nayer B, Walford EC, Johnson KB, Gaidosh G, Reiser J, De La Cruz-Munoz N, Ortega LM, Nayer A. Leptin deficiency-induced obesity affects the density of mast cells in abdominal fat depots and lymph nodes in mice. Lipids Health Dis 2012; 11:21. [PMID: 22313574 PMCID: PMC3287967 DOI: 10.1186/1476-511x-11-21] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2011] [Accepted: 02/07/2012] [Indexed: 01/22/2023] Open
Abstract
Background Mast cells are implicated in the pathogenesis of obesity and insulin resistance. Here, we explored the effects of leptin deficiency-induced obesity on the density of mast cells in metabolic (abdominal fat depots, skeletal muscle, and liver) and lymphatic (abdominal lymph nodes, spleen, and thymus) organs. Fourteen-week-old male leptin-deficient ob/ob mice and their controls fed a standard chow were studied. Tissue sections were stained with toluidine blue to determine the density of mast cells. CD117/c-kit protein expression analysis was also carried out. Furthermore, mast cells containing immunoreactive tumor necrosis factor-α (TNF-α), a proinflammatory cytokine involved in obesity-linked insulin resistance, were identified by immunostaining. Results ob/ob mice demonstrated adiposity and insulin resistance. In abdominal fat depots, mast cells were distributed differentially. While most prevalent in subcutaneous fat in controls, mast cells were most abundant in epididymal fat in ob/ob mice. Leptin deficiency-induced obesity was accompanied by a 20-fold increase in the density of mast cells in epididymal fat, but a 13-fold decrease in subcutaneous fat. This finding was confirmed by CD117/c-kit protein expression analysis. Furthermore, we found that a subset of mast cells in epididymal and subcutaneous fat were immunoreactive for TNF-α. The proportion of mast cells immunoreactive for TNF-α was higher in epididymal than in subcutaneous fat in both ob/ob and control mice. Mast cells were also distributed differentially in retroperitoneal, mesenteric, and inguinal lymph nodes. In both ob/ob mice and lean controls, mast cells were more prevalent in retroperitoneal than in mesenteric and inguinal lymph nodes. Leptin deficiency-induced obesity was accompanied by increased mast cell density in all lymph node stations examined. No significant difference in the density of mast cells in skeletal muscle, liver, spleen, and thymus was noted between ob/ob and control mice. Conclusions This study demonstrates that leptin deficiency-induced obesity is accompanied by alterations in the density of mast cells in abdominal fat depots. The divergent distribution of mast cells in subcutaneous versus visceral fat might partially account for their differential biological behavior. Mast cells might also play a role in adaptive immune response occurring in regional lymph nodes in obesity.
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Affiliation(s)
- Mehmet M Altintas
- Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL, USA
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1413
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Changes in the small intestine ofSchistosoma mansoni-infected mice fed a high-fat diet. Parasitology 2012; 139:716-25. [DOI: 10.1017/s0031182011002307] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
SUMMARYThe consumption of a high-fat diet modifies both the morphology of the small intestine and experimentally tested effects of schistosomiasis mansoni. However, whether a schistosomiasis infection associated with a high-fat diet causes injury to the small intestine has never been investigated. Mice were fed either a high-fat or a standard-fat diet for 6 months and were then infected withSchistosoma mansonicercariae. Physical characteristics of the intestinal tissue (mucosal thickness, small intestinal villi length and height, and abundance of goblet cells and enterocytes on the villous surface) and the distribution of granulomas along the intestinal segments and their developmental stage were measured at the time of sacrifice (9 or 17 weeks post-infection). The group fed a high-fat diet exhibited different granuloma stages, whereas the control group possessed only exudative granulomas. The chronically infected mice fed a high-fat diet exhibited higher granuloma and egg numbers than the acutely infected group. Exudative, exudative/exudative-productive and exudative-productive granulomas were present irrespective of diet. Computer-aided morphometric analysis confirmed that villus length, villus width, muscular height and submucosal height of the duodenal and jejunal segments were affected by diet and infection. In conclusion, a high-fat diet and infection had a significant impact on the small intestine morphology and morphometry among the animals tested.
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1414
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Yoshimura K, Eto H, Kato H, Doi K, Aoi N. In vivo manipulation of stem cells for adipose tissue repair/reconstruction. Regen Med 2012; 6:33-41. [PMID: 21999260 DOI: 10.2217/rme.11.62] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Many features of adipose stem/progenitor cells, including their physiological functions and localization, have been clarified in the past decade. Adipose tissue turns over very slowly, with perivascular progenitor cells differentiating into new adipocytes to replace dead adipocytes. A number of clinical trials using freshly isolated or cultured adipose-derived stromal cells containing adipose progenitor/stem cells are ongoing. Therapeutic use of adipose stem/progenitor cells has been shown to promote angiogenesis and adipose tissue regeneration. Identification of adipocyte-releasing factors upon apoptosis/necrosis would be a breakthrough and could lead to the next stage for adipose tissue regeneration. Activation of precursors in perichondrium and periosteum shows a dramatic neogenesis by simple injection and is an ideal example of in situ tissue engineering. The 'hit and catch' strategy using a mobilizer of bone-marrow stem/progenitor cells (hit) and attractants to lead the cells to proper homing into the target tissue (catch) may be the future of stem cell manipulation. Careful design of the microenvironment, cell delivery protocol to avoid unexpected behavior and induce maximal potential, and selection of target diseases, will be critical to the success of clinical applications of adipose-derived stromal cells.
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Affiliation(s)
- Kotaro Yoshimura
- Department of Plastic Surgery, University of Tokyo School of Medicine, 7-3-1, Hongo, Bunkyo-Ku, Tokyo 113-8655, Japan.
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1415
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Xu JM, Shi GP. Emerging role of mast cells and macrophages in cardiovascular and metabolic diseases. Endocr Rev 2012; 33:71-108. [PMID: 22240242 PMCID: PMC3365842 DOI: 10.1210/er.2011-0013] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2011] [Accepted: 09/12/2011] [Indexed: 12/11/2022]
Abstract
Mast cells are essential in allergic immune responses. Recent discoveries have revealed their direct participation in cardiovascular diseases and metabolic disorders. Although more sophisticated mechanisms are still unknown, data from animal studies suggest that mast cells act similarly to macrophages and other inflammatory cells and contribute to human diseases through cell-cell interactions and the release of proinflammatory cytokines, chemokines, and proteases to induce inflammatory cell recruitment, cell apoptosis, angiogenesis, and matrix protein remodeling. Reduced cardiovascular complications and improved metabolic symptoms in animals receiving over-the-counter antiallergy medications that stabilize mast cells open another era of mast cell biology and bring new hope to human patients suffering from these conditions.
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Affiliation(s)
- Jia-Ming Xu
- Department of Medicine, Nanfang Hospital and Southern Medical University, Guangzhou 510515, China
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1416
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Kalupahana NS, Moustaid-Moussa N. The renin-angiotensin system: a link between obesity, inflammation and insulin resistance. Obes Rev 2012; 13:136-49. [PMID: 22034852 DOI: 10.1111/j.1467-789x.2011.00942.x] [Citation(s) in RCA: 189] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The renin-angiotensin system (RAS) is classically known for its role in regulation of blood pressure, fluid and electrolyte balance. Recently, several local RASs in organs such as brain, heart, pancreas and adipose tissue have also been identified. Evidence from clinical trials suggests that in addition to anti-hypertensive effects, pharmacological inhibition of RAS also provides protection against the development of type-2 diabetes. Moreover, animal models with targeted inactivation of RAS genes exhibit improved insulin sensitivity and are protected from high-fat diet-induced obesity and insulin resistance. Because there is evidence for RAS overactivation in obesity, it is possible that RAS is a link between obesity and insulin resistance. This review summarizes the evidence and mechanistic insights on the associations between RAS, obesity and insulin resistance, with special emphasis on the role of adipose tissue RAS in the pathogenesis of metabolic derangements in obesity.
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Affiliation(s)
- N S Kalupahana
- Obesity Research Center, The University of Tennessee, Knoxville, TN 37996-4588, USA
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1417
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Kim SJ, Choi Y, Choi YH, Park T. Obesity activates toll-like receptor-mediated proinflammatory signaling cascades in the adipose tissue of mice. J Nutr Biochem 2012; 23:113-22. [DOI: 10.1016/j.jnutbio.2010.10.012] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2009] [Revised: 10/08/2010] [Accepted: 10/28/2010] [Indexed: 02/06/2023]
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1418
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van der Weerd K, Dik WA, Schrijver B, Schweitzer DH, Langerak AW, Drexhage HA, Kiewiet RM, van Aken MO, van Huisstede A, van Dongen JJ, van der Lelij AJ, Staal FJ, van Hagen PM. Morbidly obese human subjects have increased peripheral blood CD4+ T cells with skewing toward a Treg- and Th2-dominated phenotype. Diabetes 2012; 61:401-8. [PMID: 22228716 PMCID: PMC3266399 DOI: 10.2337/db11-1065] [Citation(s) in RCA: 122] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Obesity is associated with local T-cell abnormalities in adipose tissue. Systemic obesity-related abnormalities in the peripheral blood T-cell compartment are not well defined. In this study, we investigated the peripheral blood T-cell compartment of morbidly obese and lean subjects. We determined all major T-cell subpopulations via six-color flow cytometry, including CD8+ and CD4+ T cells, CD4+ T-helper (Th) subpopulations, and natural CD4+CD25+FoxP3+ T-regulatory (Treg) cells. Moreover, molecular analyses to assess thymic output, T-cell proliferation (T-cell receptor excision circle analysis), and T-cell receptor-β (TCRB) repertoire (GeneScan analysis) were performed. In addition, we determined plasma levels of proinflammatory cytokines and cytokines associated with Th subpopulations and T-cell proliferation. Morbidly obese subjects had a selective increase in peripheral blood CD4+ naive, memory, natural CD4+CD25+FoxP3+ Treg, and Th2 T cells, whereas CD8+ T cells were normal. CD4+ and CD8+ T-cell proliferation was increased, whereas the TCRB repertoire was not significantly altered. Plasma levels of cytokines CCL5 and IL-7 were elevated. CD4+ T-cell numbers correlated positively with fasting insulin levels. The peripheral blood T-cell compartment of morbidly obese subjects is characterized by increased homeostatic T-cell proliferation to which cytokines IL-7 and CCL5, among others, might contribute. This is associated with increased CD4+ T cells, with skewing toward a Treg- and Th2-dominated phenotype, suggesting a more anti-inflammatory set point.
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Affiliation(s)
- Kim van der Weerd
- Department of Immunology, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Willem A. Dik
- Department of Immunology, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Benjamin Schrijver
- Department of Immunology, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Dave H. Schweitzer
- Department of Internal Medicine, Reinier de Graaf Group of Hospitals, Delft, the Netherlands
| | - Anton W. Langerak
- Department of Immunology, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Hemmo A. Drexhage
- Department of Immunology, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Rosalie M. Kiewiet
- Department of Internal Medicine, Albert Schweitzer Hospital, Dordrecht, the Netherlands
| | | | | | | | - Aart-Jan van der Lelij
- Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Frank J.T. Staal
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, the Netherlands
| | - P. Martin van Hagen
- Department of Immunology, Erasmus University Medical Center, Rotterdam, the Netherlands
- Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, the Netherlands
- Corresponding author: P. Martin van Hagen,
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1419
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Shi MA, Shi GP. Different roles of mast cells in obesity and diabetes: lessons from experimental animals and humans. Front Immunol 2012; 3:7. [PMID: 22566893 PMCID: PMC3341969 DOI: 10.3389/fimmu.2012.00007] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Accepted: 01/09/2012] [Indexed: 12/18/2022] Open
Abstract
Mast cells (MCs) play an important role in allergic hyperresponsiveness and in defending microorganism infections. Recent studies of experimental animals and humans have suggested that MCs participate in obesity and diabetes. MC distribution and activities in adipose tissues may vary, depending on the locations of different adipose tissues. In addition to releasing inflammatory mediators to affect adipose tissue extracellular matrix remodeling and to promote inflammatory cell recruitment and proliferation, MCs directly and indirectly interact and activate adipose tissue cells, including adipocytes and recruited inflammatory cells. Plasma MC protease levels are significantly higher in obese patients than in lean subjects. Experimental obese animals lose body weight after MC inactivation. MC functions in diabetes are even more complicated, and depend on the type of diabetes and on different diabetic complications. Both plasma MC proteases and MC activation essential immunoglobulin E levels are significant risk factors for human pre-diabetes and diabetes mellitus. MC stabilization prevents diet-induced diabetes and improves pre-established diabetes in experimental animals. MC depletion or inactivation can improve diet-induced type 2 diabetes and some forms of type 1 diabetes, but also can worsen other forms of type 1 diabetes, at least in experimental animals. Observations from animal and human studies have suggested beneficial effects of treating diabetic patients with MC stabilizers. Some diabetic patients may benefit from enhancing MC survival and proliferation – hypotheses that merit detailed basic researches and clinical studies.
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Affiliation(s)
- Michael A Shi
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School Boston, MA, USA
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1420
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Brooks-Worrell B, Palmer JP. Immunology in the Clinic Review Series; focus on metabolic diseases: development of islet autoimmune disease in type 2 diabetes patients: potential sequelae of chronic inflammation. Clin Exp Immunol 2012; 167:40-6. [PMID: 22132883 DOI: 10.1111/j.1365-2249.2011.04501.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Historically, the development of type 2 diabetes has been considered not to have an autoimmune component, in contrast to the autoimmune pathogenesis of type 1 diabetes. In this review we will discuss the accumulating data supporting the concept that islet autoreactivity and inflammation is present in type 2 diabetes pathogenesis, and the islet autoimmunity appears to be one of the factors associated with the progressive nature of the type 2 diabetes disease process.
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Affiliation(s)
- B Brooks-Worrell
- Department of Medicine, University of Washington, Seattle, WA, USA.
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1421
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Abstract
Over the last decades the rising occurrence of metabolic diseases throughout the world points to the failure of preventive and therapeutic strategies and of the corresponding molecular and physiological concepts. Therefore, a new paradigm needs to be elucidated. Very recently the intimate cross talk of the intestinal microbiota with the host immune system has opened new avenues. The large diversity of the intestinal microbes' genome, i.e. the metagenome, and the extreme plasticity of the immune system provide a unique balance which, when finely tuned, maintains a steady homeostasis. The discovery that a new microbiota repertoire is one of the causes responsible for the onset of metabolic disease suggests that the relationship with the immune system is impaired. Therefore, we here review the recent arguments that support the view that an alteration in the microbiota to host immune system balance leads to an increased translocation of bacterial antigens towards metabolically active tissues, and could result in a chronic inflammatory state and consequently impaired metabolic functions such as insulin resistance, hepatic fat deposition, insulin unresponsiveness, and excessive adipose tissue development. This imbalance could be at the onset of metabolic disease, and therefore the early treatment of the microbiota dysbiosis or immunomodulatory strategies should prevent and slow down the epidemic of metabolic diseases and hence the corresponding lethal cardiovascular consequences.
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Affiliation(s)
- Rémy Burcelin
- Institut National de la Santé et de la Recherche Médicale, U1048, Institut des Maladies Métaboliques et Cardiovasculaires (I2MC), BP 84225, 31432 Toulouse, France.
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1422
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The adaptive immune system as a fundamental regulator of adipose tissue inflammation and insulin resistance. Immunol Cell Biol 2012; 90:755-62. [PMID: 22231651 DOI: 10.1038/icb.2011.110] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Over the past decade, chronic inflammation in visceral adipose tissue (VAT) has gained acceptance as a lead promoter of insulin resistance in obesity. A great deal of evidence has pointed to the role of adipokines and innate immune cells, in particular, adipose tissue macrophages, in the regulation of fat inflammation and glucose homeostasis. However, more recently, cells of the adaptive immune system, specifically B and T lymphocytes, have emerged as unexpected promoters and controllers of insulin resistance. These adaptive immune cells infiltrate obesity expanded VAT and through cytokine secretion and macrophage modulation dictate the extent of the local inflammatory response, thereby directly impacting insulin resistance. The remarkable ability of our adaptive immune system to regulate insulin sensitivity and metabolism has unmasked a novel physiological function of this system, and promises new diagnostic and therapeutic strategies to manage the disease. This review highlights critical roles of adipose tissue lymphocytes in governing glucose homeostasis.
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1423
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Kyaw T, Tay C, Hosseini H, Kanellakis P, Gadowski T, MacKay F, Tipping P, Bobik A, Toh BH. Depletion of B2 but not B1a B cells in BAFF receptor-deficient ApoE mice attenuates atherosclerosis by potently ameliorating arterial inflammation. PLoS One 2012; 7:e29371. [PMID: 22238605 PMCID: PMC3251583 DOI: 10.1371/journal.pone.0029371] [Citation(s) in RCA: 130] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2011] [Accepted: 11/27/2011] [Indexed: 11/18/2022] Open
Abstract
We have recently identified conventional B2 cells as atherogenic and B1a cells as atheroprotective in hypercholesterolemic ApoE−/− mice. Here, we examined the development of atherosclerosis in BAFF-R deficient ApoE−/− mice because B2 cells but not B1a cells are selectively depleted in BAFF-R deficient mice. We fed BAFF-R−/− ApoE−/− (BaffR.ApoE DKO) and BAFF-R+/+ApoE−/− (ApoE KO) mice a high fat diet (HFD) for 8-weeks. B2 cells were significantly reduced by 82%, 81%, 94%, 72% in blood, peritoneal fluid, spleen and peripheral lymph nodes respectively; while B1a cells and non-B lymphocytes were unaffected. Aortic atherosclerotic lesions assessed by oil red-O stained-lipid accumulation and CD68+ macrophage accumulation were decreased by 44% and 50% respectively. B cells were absent in atherosclerotic lesions of BaffR.ApoE DKO mice as were IgG1 and IgG2a immunoglobulins produced by B2 cells, despite low but measurable numbers of B2 cells and IgG1 and IgG2a immunoglobulin concentrations in plasma. Plasma IgM and IgM deposits in atherosclerotic lesions were also reduced. BAFF-R deficiency in ApoE−/− mice was also associated with a reduced expression of VCAM-1 and fewer macrophages, dendritic cells, CD4+ and CD8+ T cell infiltrates and PCNA+ cells in lesions. The expression of proinflammatory cytokines, TNF-α, IL1-β and proinflammatory chemokine MCP-1 was also reduced. Body weight and plasma cholesterols were unaffected in BaffR.ApoE DKO mice. Our data indicate that B2 cells are important contributors to the development of atherosclerosis and that targeting the BAFF-R to specifically reduce atherogenic B2 cell numbers while preserving atheroprotective B1a cell numbers may be a potential therapeutic strategy to reduce atherosclerosis by potently reducing arterial inflammation.
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Affiliation(s)
- Tin Kyaw
- Vascular Biology and Atherosclerosis Laboratory, Baker IDI Heart and Diabetes Institute, Victoria, Australia.
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1424
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Nishimura S, Nagasaki M, Sugita J. Adipose tissue remodeling associated with chronic inflammation and abnormal local immunity in obesity visualized by in vivo molecular imaging method. Inflamm Regen 2012. [DOI: 10.2492/inflammregen.32.165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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1425
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Depression and type 2 diabetes: Inflammatory mechanisms of a psychoneuroendocrine co-morbidity. Neurosci Biobehav Rev 2012; 36:658-76. [DOI: 10.1016/j.neubiorev.2011.10.001] [Citation(s) in RCA: 168] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Revised: 10/01/2011] [Accepted: 10/05/2011] [Indexed: 01/28/2023]
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1426
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Abstract
Obesity may be viewed as a chronic low-grade inflammatory disease as well as a metabolic disease. Indeed, unbalanced production of pro- and anti-inflammatory adipocytokines critically contributes to the obesity-induced insulin resistance. In addition to lipid-laden mature adipocytes, adipose tissue is composed of various stromal cells such as preadipocytes, endothelial cells, fibroblasts, and immune cells that may be involved in adipose tissue functions. Accumulating evidence has suggested that adipocytes and stromal cells in adipose tissue change dramatically in number and cell type during the course of obesity, which is referred to as "adipose tissue remodeling." Among stromal cells, infiltration of macrophages in obese adipose tissue precedes the development of insulin resistance in animal models, suggesting that they are crucial for adipose tissue inflammation. We have provided evidence suggesting that a paracrine loop involving saturated fatty acids and tumor necrosis factor-α derived from adipocytes and macrophages, respectively, aggravates obesity-induced adipose tissue inflammation. On the other hand, storing excessive energy as triglyceride is also a fundamental function of adipose tissue. Recent evidence suggests that reduced lipid storage in obese adipose tissue contributes to ectopic lipid accumulation in non-adipose tissues such as the liver, skeletal muscle, and pancreas, where lipotoxicity impairs their metabolic functions. Notably, chronic inflammation is capable of inducing insulin resistance, lipolysis, and interstitial fibrosis in adipose tissue, all of which may reduce the lipid-storing function. Understanding the molecular mechanism underlying adipose tissue remodeling may lead to the identification of novel therapeutic strategies to prevent or treat obesity-induced adipose tissue inflammation.
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Affiliation(s)
- Takayoshi Suganami
- Department of Molecular Medicine and Metabolism, Medical Research Institute, Tokyo Medical and Dental University, Tokyo, Japan
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1427
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Na SY, Myung SJ. Obesity and Colorectal Cancer. THE KOREAN JOURNAL OF GASTROENTEROLOGY 2012; 59:16-26. [DOI: 10.4166/kjg.2012.59.1.16] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Soo-Young Na
- Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Seung-Jae Myung
- Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
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1428
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Hu J, Li C, Wang L, Zhang X, Zhang M, Gao H, Yu X, Wang F, Zhao W, Yan S, Wang Y. Long term effects of the implantation of autologous bone marrow mononuclear cells for type 2 diabetes mellitus. Endocr J 2012; 59:1031-9. [PMID: 22814142 DOI: 10.1507/endocrj.ej12-0092] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Previous studies have shown that several types of stem cells can differentiate into insulin-secreting islet beta-cells and that these cells can reduce blood glucose in some trials, but there has been no report of a long-term follow-up. We assessed the long-term effects of the use of autologous bone marrow mononuclear cells in the treatment of type 2 diabetes mellitus (T2DM). Based on the willingness to receive implantation of bone marrow mononuclear cells, One hundred and eighteen patients with T2DM were divided into two groups; the patients in group I were treated with autologous bone marrow mononuclear cells and patients in group II were treated with insulin intensification therapy. Mononuclear cells from bone marrow were injected back into the patient's pancreas via a catheter. Patients were followed-up after the operation at monthly intervals for the first 3 months and thereafter every 3 months for the next 33 months, the occurrence of any side effects and the results of laboratory examinations were evaluated. There were no reported acute or chronic side effects in group I and both the HbA1c and C-peptide in group I patients were significantly better than either pretherapy values or group II patients during the follow-up period. These data suggested that the implantation of autologous bone marrow mononuclear cells for the treatment of T2DM is safe and effective. This therapy can partially restore the function of islet beta-cells and maintain blood glucose homeostasis in a longer time.
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Affiliation(s)
- Jianxia Hu
- Stem Cell Research Center, the Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003, China
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1429
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Styskal J, Van Remmen H, Richardson A, Salmon AB. Oxidative stress and diabetes: what can we learn about insulin resistance from antioxidant mutant mouse models? Free Radic Biol Med 2012; 52:46-58. [PMID: 22056908 PMCID: PMC3249484 DOI: 10.1016/j.freeradbiomed.2011.10.441] [Citation(s) in RCA: 166] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Revised: 10/12/2011] [Accepted: 10/13/2011] [Indexed: 01/18/2023]
Abstract
The development of metabolic dysfunctions like diabetes and insulin resistance in mammals is regulated by a myriad of factors. Oxidative stress seems to play a central role in this process as recent evidence shows a general increase in oxidative damage and a decrease in oxidative defense associated with several metabolic diseases. These changes in oxidative stress can be directly correlated with increased fat accumulation, obesity, and consumption of high-calorie/high-fat diets. Modulation of oxidant protection through either genetic mutation or treatment with antioxidants can significantly alter oxidative stress resistance and accumulation of oxidative damage in laboratory rodents. Antioxidant mutant mice have previously been utilized to examine the role of oxidative stress in other disease models, but have been relatively unexplored as models to study the regulation of glucose metabolism. In this review, we will discuss the evidence for oxidative stress as a primary mechanism linking obesity and metabolic disorders and whether alteration of antioxidant status in laboratory rodents can significantly alter the development of insulin resistance or diabetes.
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Affiliation(s)
- Jennalynn Styskal
- The Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, TX 78245-3207, USA
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1430
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Shapiro H, Lutaty A, Ariel A. Macrophages, meta-inflammation, and immuno-metabolism. ScientificWorldJournal 2011; 11:2509-29. [PMID: 22235182 PMCID: PMC3253544 DOI: 10.1100/2011/397971] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2011] [Accepted: 11/29/2011] [Indexed: 02/07/2023] Open
Abstract
Current research depicts specific modes of immunity and energy metabolism as being interrelated at the molecular, cellular, organ and organism level. Hence, whereas M2 (alternatively-activated) macrophages dominate insulin-sensitive adipose tissue in the lean, M1-skewed (classically-activated) macrophages accumulate in parallel to adiposity in the obese, and promote inflammation and insulin resistance, that is, meta-inflammation. The latest frontier of immuno-metabolism explores the coregulation of energy metabolism and immune function within hematopoietic cells. M1-skewed macrophages are sustained in edematous, hypoxic tissues by anaerobic glycolysis, whereas mitochondrial biogenesis and respiration dominates in M2 cells. We review the underlying mechanisms and the consequences of the transition from M2 to M1 predominance in adipose tissue, as well as the extracellular signals and transcription factors that control macrophage phenotypes and impose distinct metabolic modes.
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Affiliation(s)
- Haim Shapiro
- Department of Biology, Faculty of Natural Sciences, University of Haifa, Haifa 31905, Israel
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1431
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Penas-Steinhardt A, Tellechea¹ ML, Gomez-Rosso L, Brites F, Frechtel GD, Poskus E. Association of common variants in JAK2 gene with reduced risk of metabolic syndrome and related disorders. BMC MEDICAL GENETICS 2011; 12:166. [PMID: 22185674 PMCID: PMC3259043 DOI: 10.1186/1471-2350-12-166] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/04/2011] [Accepted: 12/20/2011] [Indexed: 12/13/2022]
Abstract
BACKGROUND Disturbances in leptin and insulin signaling pathways are related to obesity and metabolic syndrome (MS) with increased risk of diabetes and cardiovascular disease. Janus kinase 2 (JAK2) is a tyrosine kinase involved in the activation of mechanisms that mediate leptin and insulin actions. We conducted a population cross-sectional study to explore the association between two common variants in JAK2 gene and MS related traits in 724 Argentinean healthy male subjects. METHODS A total of 724 unrelated men aged 37.11 ± 10.91 yr were included in a cross-sectional study. Physical examination, anthropometric measurements and biochemical analysis were determined by a standardized protocol. rs7849191 and rs3780378 were genotyped. Analyses were done separately for each SNP and followed up by haplotype analysis. RESULTS rs7849191 and rs3780378 were both associated with reduced risk of MS [p = 0.005; OR (95%CI) = 0.52 (0.33-0.80) and p = 0.006; OR (95% CI) = 0.59 (0.40-0.86) respectively, assuming a dominant model]. rs3780378 T allele was associated with triglyceridemia values under 150 mg/dl [p = 0.007; OR (95%CI) = 0.610 (0.429-0.868)] and TT carriers showed lower triglycerides (p = 0.017), triglycerides/HDL-C ratio (p = 0.022) and lipid accumulation product (p = 0.007) compared to allele C carriers. The two-SNPs-haplotype analysis was consistent with single locus analysis. CONCLUSIONS It was found for the first time, significant associations of JAK2 common variants and related haplotypes with reduced risk of MS. These findings could be explained by the role of JAK2 in insulin and/or leptin signaling.
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Affiliation(s)
- Alberto Penas-Steinhardt
- Humoral Immunity Institute "Prof. Ricardo A. Margni" (IDEHU), National Research Council (CONICET) & Chair of Immunology, School of Pharmacy and Biochemistry, University of Buenos Aires (UBA) - Argentina
| | - Mariana L Tellechea¹
- Humoral Immunity Institute "Prof. Ricardo A. Margni" (IDEHU), National Research Council (CONICET) & Chair of Immunology, School of Pharmacy and Biochemistry, University of Buenos Aires (UBA) - Argentina
- Chair of Genetic, Department of Microbiology, Inmunology and Biotecnology, School of Pharmacy and Biochemistry, University of Buenos Aires (UBA) - Argentina
| | - Leonardo Gomez-Rosso
- Laboratory of Lipids and lipoproteins, Department of Clinical Biochemistry, School of Pharmacy and Biochemistry. National Research Council (CONICET) & University of Buenos Aires (UBA) - Argentina
| | - Fernando Brites
- Laboratory of Lipids and lipoproteins, Department of Clinical Biochemistry, School of Pharmacy and Biochemistry. National Research Council (CONICET) & University of Buenos Aires (UBA) - Argentina
| | - Gustavo D Frechtel
- Chair of Genetic, Department of Microbiology, Inmunology and Biotecnology, School of Pharmacy and Biochemistry, University of Buenos Aires (UBA) - Argentina
- Genetics Division, Clinical Hospital "José de San Martín", University of Buenos Aires (UBA) - Argentina
| | - Edgardo Poskus
- Chair of Genetic, Department of Microbiology, Inmunology and Biotecnology, School of Pharmacy and Biochemistry, University of Buenos Aires (UBA) - Argentina
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1432
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Abstract
Human obesity can be viewed as a set of phenotypes that evolve over time in a sequence of stages that need to be precisely measured. Environmental, behavioral, genetic and biological factors interact to cause obesity. This presentation provides a clinical viewpoint on some biological processes that may explain some of the stages in the development of human obesity, its chronic maintenance and occurrence of complications, with a focus on brain structures, genetics, the profound alterations in adipose tissue biology and gut microbiota components. Roux-en-Y gastric bypass surgery is an increasingly effective model to study in this context because it leads to major improvements in glucose and lipid homeostasis and to the amelioration of some systemic inflammatory markers.
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1433
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Effect of citrus polyphenol- and curcumin-supplemented diet on inflammatory state in obese cats. Br J Nutr 2011; 106 Suppl 1:S198-201. [PMID: 22005428 DOI: 10.1017/s0007114511002492] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Among obesity-associated disorders, low-grade inflammation has been described. The putative therapeutic properties of citrus and curcumin polyphenols could be associated with their anti-inflammatory properties. Two diets supplemented either with hesperidin (0.05 %) and naringin (0.1 %) from citrus extract or with highly bioavailable curcumin from Curcuma longa extract (0.09 %) were fed to eight obese cats for two 8-week periods (cross-over study design) while maintaining animals in an obese state. Plasma acute-phase protein (APP; α1-acid glycoprotein (AGP), serum amyloid A and haptoglobin) levels were assessed before and at the end of each test period. TNF-α, IL-1β, IL-2, IL-4, IL-5, IL-10, IL-12, IL-18, transforming growth factor-β, interferon (IFN)-γ mRNA levels were determined in peripheral blood mononuclear cells (PBMC) by real-time PCR. Compared with pre-study values, supplementation with citrus polyphenols resulted in lower plasma AGP and haptoglobin concentrations, while that with curcumin resulted in lower plasma AGP concentration. There were no differences between the supplementations. TNF-α, IL-1β, IL-4, IL-5, IL-10, IL-12, IL-18, transforming growth factor-β, mRNA levels remained unaffected by either dietary supplementation. In contrast, IFN-γ and IL-2 mRNA levels were lower at the end of the citrus and the curcumin supplementation, respectively. There were no differences between the supplementations. The present study results show a slight effect of citrus and curcumin supplementation on inflammatory markers expressed by PBMC, and a decreased concentration of APP, which are mainly expressed by the liver. This would confirm that hesperidin and naringin or highly bioavailable curcumin extract have beneficial effects, targeted in the liver and could improve the obesity-related inflammatory state.
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1434
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Affiliation(s)
- Kae Won Cho
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, Michigan
| | - Carey N. Lumeng
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, Michigan
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan
- Corresponding author: Carey N. Lumeng,
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1435
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Hamed EA, Zakary MM, Ahmed NS, Gamal RM. Circulating leptin and insulin in obese patients with and without type 2 diabetes mellitus: relation to ghrelin and oxidative stress. Diabetes Res Clin Pract 2011; 94:434-41. [PMID: 21924513 DOI: 10.1016/j.diabres.2011.08.023] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2011] [Revised: 08/02/2011] [Accepted: 08/19/2011] [Indexed: 12/22/2022]
Abstract
AIM This case control study aimed to investigate relationship between appetite hormones (ghrelin and leptin) and body mass index (BMI), insulin and oxidative stress in simple obese and type 2 diabetes (T2DM) obese patients. METHODS Thirty healthy controls; 30 simple obese and 30 T2DM obese patients were enrolled. Demographic and clinical data of all participants were reported. Serum levels of fasting blood glucose (FBG), postprandial blood glucose (PBG), lipid peroxide (LPO) and nitric oxide (NO) were measured by chemical methods while, insulin, leptin and ghrelin by ELISA kits. RESULTS Serum levels of insulin, leptin, LPO were significantly higher while, ghrelin was significantly lower in simple obese and obese patients with diabetes versus controls. Insulin resistance was found in 76.67% simple obese and 93.33% obese patients with diabetes. Ghrelin showed a positive correlation with PBG in controls; but negative correlation with BMI in simple obese and with NO in obese patients with diabetes. Positive correlations were found between LPO and FBG, insulin, homeostasis model assessment of insulin resistance (HOMA-IR) and between leptin and FBG in obese patients with diabetes. CONCLUSIONS Our results suggested that hyperinsulinemia and hyperleptinemia may be most important mechanisms in decreasing ghrelin and inducing oxidative stress in simple obese and T2DM obese patients.
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Affiliation(s)
- Enas A Hamed
- Department of Physiology, Faculty of Medicine, Assiut University, P.O. Box 71526, Assiut, Egypt.
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1436
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Kim CS, Kim JG, Lee BJ, Choi MS, Choi HS, Kawada T, Lee KU, Yu R. Deficiency for costimulatory receptor 4-1BB protects against obesity-induced inflammation and metabolic disorders. Diabetes 2011; 60:3159-68. [PMID: 21998397 PMCID: PMC3219944 DOI: 10.2337/db10-1805] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
OBJECTIVE Inflammation is an important factor in the development of insulin resistance, type 2 diabetes, and fatty liver disease. As a member of the tumor necrosis factor receptor superfamily (TNFRSF9) expressed on immune cells, 4-1BB/CD137 provides a bidirectional inflammatory signal through binding to its ligand 4-1BBL. Both 4-1BB and 4-1BBL have been shown to play an important role in the pathogenesis of various inflammatory diseases. RESEARCH DESIGN AND METHODS Eight-week-old male 4-1BB-deficient and wild-type (WT) mice were fed a high-fat diet (HFD) or a regular diet for 9 weeks. RESULTS We demonstrate that 4-1BB deficiency protects against HFD-induced obesity, glucose intolerance, and fatty liver disease. The 4-1BB-deficient mice fed an HFD showed less body weight gain, adiposity, adipose infiltration of macrophages/T cells, and tissue levels of inflammatory cytokines (e.g., TNF-α, interleukin-6, and monocyte chemoattractant protein-1 [MCP-1]) compared with HFD-fed control mice. HFD-induced glucose intolerance/insulin resistance and fatty liver were also markedly attenuated in the 4-1BB-deficient mice. CONCLUSIONS These findings suggest that 4-1BB and 4-1BBL may be useful therapeutic targets for combating obesity-induced inflammation and metabolic disorders.
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Affiliation(s)
- Chu-Sook Kim
- Department of Food Science and Nutrition, University of Ulsan, Ulsan, South Korea
| | - Jae Geun Kim
- Department of Biological Science, University of Ulsan, Ulsan, South Korea
| | - Byung-Ju Lee
- Department of Biological Science, University of Ulsan, Ulsan, South Korea
| | - Myung-Sook Choi
- Department of Food Science and Nutrition, Kyungpook National University, Daegu, South Korea
| | - Hye-Sun Choi
- Department of Biological Science, University of Ulsan, Ulsan, South Korea
| | - Teruo Kawada
- Graduate School of Agriculture, Kyoto University, Uji, Kyoto, Japan
| | - Ki-Up Lee
- Department of Internal Medicine, University of Ulsan College of Medicine, Seoul, South Korea
| | - Rina Yu
- Department of Food Science and Nutrition, University of Ulsan, Ulsan, South Korea
- Corresponding author: Rina Yu,
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1437
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1438
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Kumarasamy S, Gopalakrishnan K, Kim DH, Abraham NG, Johnson WD, Joe B, Gupta AK. Dysglycemia induces abnormal circadian blood pressure variability. Cardiovasc Diabetol 2011; 10:104. [PMID: 22108527 PMCID: PMC3247849 DOI: 10.1186/1475-2840-10-104] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Accepted: 11/22/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Prediabetes (PreDM) in asymptomatic adults is associated with abnormal circadian blood pressure variability (abnormal CBPV). HYPOTHESIS Systemic inflammation and glycemia influence circadian blood pressure variability. METHODS Dahl salt-sensitive (S) rats (n = 19) after weaning were fed either an American (AD) or a standard (SD) diet. The AD (high-glycemic-index, high-fat) simulated customary human diet, provided daily overabundant calories which over time lead to body weight gain. The SD (low-glycemic-index, low-fat) mirrored desirable balanced human diet for maintaining body weight. Body weight and serum concentrations for fasting glucose (FG), adipokines (leptin and adiponectin), and proinflammatory cytokines [monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-α (TNF-α)] were measured. Rats were surgically implanted with C40 transmitters and blood pressure (BP-both systolic; SBP and diastolic; DBP) and heart rate (HR) were recorded by telemetry every 5 minutes during both sleep (day) and active (night) periods. Pulse pressure (PP) was calculated (PP = SBP-DBP). RESULTS [mean(SEM)]: The AD fed group displayed significant increase in body weight (after 90 days; p < 0.01). Fasting glucose, adipokine (leptin and adiponectin) concentrations significantly increased (at 90 and 172 days; all p < 0.05), along with a trend for increased concentrations of systemic pro-inflammatory cytokines (MCP-1 and TNF-α) on day 90. The AD fed group, with significantly higher FG, also exhibited significantly elevated circadian (24-hour) overall mean SBP, DBP, PP and HR (all p < 0.05). CONCLUSION These data validate our stated hypothesis that systemic inflammation and glycemia influence circadian blood pressure variability. This study, for the first time, demonstrates a cause and effect relationship between caloric excess, enhanced systemic inflammation, dysglycemia, loss of blood pressure control and abnormal CBPV. Our results provide the fundamental basis for examining the relationship between dysglycemia and perturbation of the underlying mechanisms (adipose tissue dysfunction induced local and systemic inflammation, insulin resistance and alteration of adipose tissue precursors for the renin-aldosterone-angiotensin system) which generate abnormal CBPV.
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Affiliation(s)
- Sivarajan Kumarasamy
- Department of Physiology and Pharmacology, University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA
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1439
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Abstract
Histone acetyltransferases (HATs) and histone deacetylases (HDACs) mediate acetylation and deacetylation of histone proteins and transcription factors. There is abundant evidence that these enzymes regulate the acetylation state of many cytoplasmic proteins, including lysine residues in important metabolic enzymes. Lysine acetylation regulates major cellular functions as a common post-transcriptional modification of proteins, conserved from prokaryotes to humans. In this article, we refer to HATs and HDACs broadly as lysine acetyltransferases (KATs) and deacetylases (KDACs). Lysine acetylation is vitally important in both immunological and metabolic pathways and may regulate the balance between energy storage and expenditure. Obesity, type II diabetes and cardiovascular disease (metabolic syndrome) are widely recognised as features of a chronic low-grade inflammatory state, involving significant alterations in primary immunometabolism. Identifying effective therapeutic and preventive options to treat this multi-factorial syndrome has proven to be very challenging, with an emerging focus on developing anti-inflammatory agents that can combat adiposity and metabolic disease. Here, we summarise current evidence and understanding of innate immune and metabolic pathways relevant to adiposity and metabolic disease regulated by lysine acetylation. Developing this understanding in greater detail may facilitate strategic development of novel and enzyme-specific lysine deacetylase modulators that regulate both metabolic and immune systems.
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1440
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Ogawa Y. [Obesity and homeostatic inflammation]. Nihon Yakurigaku Zasshi 2011; 138:178-81. [PMID: 22075458 DOI: 10.1254/fpj.138.178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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1441
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Galic S, Fullerton MD, Schertzer JD, Sikkema S, Marcinko K, Walkley CR, Izon D, Honeyman J, Chen ZP, van Denderen BJ, Kemp BE, Steinberg GR. Hematopoietic AMPK β1 reduces mouse adipose tissue macrophage inflammation and insulin resistance in obesity. J Clin Invest 2011; 121:4903-15. [PMID: 22080866 DOI: 10.1172/jci58577] [Citation(s) in RCA: 274] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Accepted: 10/05/2011] [Indexed: 12/17/2022] Open
Abstract
Individuals who are obese are frequently insulin resistant, putting them at increased risk of developing type 2 diabetes and its associated adverse health conditions. The accumulation in adipose tissue of macrophages in an inflammatory state is a hallmark of obesity-induced insulin resistance. Here, we reveal a role for AMPK β1 in protecting macrophages from inflammation under high lipid exposure. Genetic deletion of the AMPK β1 subunit in mice (referred to herein as β1(-/-) mice) reduced macrophage AMPK activity, acetyl-CoA carboxylase phosphorylation, and mitochondrial content, resulting in reduced rates of fatty acid oxidation. β1(-/-) macrophages displayed increased levels of diacylglycerol and markers of inflammation, effects that were reproduced in WT macrophages by inhibiting fatty acid oxidation and, conversely, prevented by pharmacological activation of AMPK β1-containing complexes. The effect of AMPK β1 loss in macrophages was tested in vivo by transplantation of bone marrow from WT or β1(-/-) mice into WT recipients. When challenged with a high-fat diet, mice that received β1(-/-) bone marrow displayed enhanced adipose tissue macrophage inflammation and liver insulin resistance compared with animals that received WT bone marrow. Thus, activation of AMPK β1 and increasing fatty acid oxidation in macrophages may represent a new therapeutic approach for the treatment of insulin resistance.
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Affiliation(s)
- Sandra Galic
- St. Vincent's Institute of Medical Research, University of Melbourne, Fitzroy, Victoria, Australia
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1442
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Origin and plasticity of MHC I-associated self peptides. Autoimmun Rev 2011; 11:627-35. [PMID: 22100331 DOI: 10.1016/j.autrev.2011.11.003] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Accepted: 11/02/2011] [Indexed: 01/13/2023]
Abstract
Endogenous peptides presented by MHC I molecules represent the essence of self for CD8 T lymphocytes. These MHC I peptides (MIPs) regulate all key events that occur during the lifetime of CD8 T cells. CD8 T cells are selected on self-MIPs, sustained by self-MIPs, and activated in the presence of self-MIPs. Recently, large-scale mass spectrometry studies have revealed that the self-MIP repertoire is more complex and plastic than previously anticipated. The composition of the self-MIP repertoire varies from one cell type to another and can be perturbed by cell-intrinsic and -extrinsic factors including dysregulation of cellular metabolism and infection. The complexity and plasticity of the self-MIP repertoire represent a major challenge for the maintenance of self tolerance and can have pervasive effects on the global functioning of the immune system.
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1443
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Cutchins A, Harmon DB, Kirby JL, Doran AC, Oldham SN, Skaflen M, Klibanov AL, Meller N, Keller SR, Garmey J, McNamara CA. Inhibitor of differentiation-3 mediates high fat diet-induced visceral fat expansion. Arterioscler Thromb Vasc Biol 2011; 32:317-24. [PMID: 22075252 DOI: 10.1161/atvbaha.111.234856] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
OBJECTIVE Inhibitor of differentiation-3 (Id3) has been implicated in promoting angiogenesis, a key determinant of high-fat diet (HFD)-induced visceral adiposity. Yet the role of Id3 in HFD-induced angiogenesis and visceral adipose expansion is unknown. METHODS AND RESULTS Id3(-/-) mice demonstrated a significant attenuation of HFD-induced visceral fat depot expansion compared to wild type littermate controls. Importantly, unlike other Id proteins, loss of Id3 did not affect adipose depot size in young mice fed chow diet or differentiation of adipocytes in vitro or in vivo. Contrast enhanced ultrasound revealed a significant attenuation of visceral fat microvascular blood volume in HFD-fed mice null for Id3 compared to wild type controls. HFD induced Id3 and VEGFA expression in the visceral stromal vascular fraction and Id3(-/-) mice had significantly lower levels of VEGFA protein in visceral adipose tissue compared to wild type. Furthermore, HFD-induced VEGFA expression in visceral adipose tissue was completely abolished by loss of Id3. Consistent with this effect, Id3 abolished E12-mediated repression of VEGFA promoter activity. CONCLUSIONS Results identify Id3 as an important regulator of HFD-induced visceral adipose VEGFA expression, microvascular blood volume, and depot expansion. Inhibition of Id3 may have potential as a therapeutic strategy to limit visceral adiposity.
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Affiliation(s)
- Alexis Cutchins
- MR5 G133, Robert M. Berne Cardiovascular Research Center, 415 Lane Rd, Charlottesville, VA 22908, USA
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1444
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Lumeng CN, Liu J, Geletka L, Delaney C, Delproposto J, Desai A, Oatmen K, Martinez-Santibanez G, Julius A, Garg S, Yung RL. Aging is associated with an increase in T cells and inflammatory macrophages in visceral adipose tissue. THE JOURNAL OF IMMUNOLOGY 2011; 187:6208-16. [PMID: 22075699 DOI: 10.4049/jimmunol.1102188] [Citation(s) in RCA: 213] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Age-related adiposity has been linked to chronic inflammatory diseases in late life. To date, the studies on adipose tissue leukocytes and aging have not taken into account the heterogeneity of adipose tissue macrophages (ATMs), nor have they examined how age impacts other leukocytes such as T cells in fat. Therefore, we have performed a detailed examination of ATM subtypes in young and old mice using state of the art techniques. Our results demonstrate qualitative changes in ATMs with aging that generate a decrease in resident type 2 (M2) ATMs. The profile of ATMs in old fat shifts toward a proinflammatory environment with increased numbers of CD206(-)CD11c(-) (double-negative) ATMs. The mechanism of this aging-induced shift in the phenotypic profile of ATMs was found to be related to a decrease in peroxisome proliferator-activated receptor-γ expression in ATMs and alterations in chemokine/chemokine receptor expression profiles. Furthermore, we have revealed a profound and unexpected expansion of adipose tissue T cells in visceral fat with aging that includes a significant induction of regulatory T cells in fat. Our findings demonstrate a unique inflammatory cell signature in the physiologic context of aging adipose tissue that differs from those induced in setting of diet-induced obesity.
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Affiliation(s)
- Carey N Lumeng
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, MI 48109, USA
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1445
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Abstract
Chronic inflammation appears to underlie most, if not all, the chronic diseases of today, including cardiovascular disease, type 2 diabetes, chronic kidney disease, Alzheimer's disease and cancer. We have demonstrated that obesity induces chronic local inflammation in adipose tissue. We also found that chronic inflammation is crucially involved in the development of heart failure and chronic kidney disease. In this article, I review recent findings reported by my group and others regarding the mechanisms underlying the chronic inflammatory processes commonly observed in adipose tissue, heart and kidney. I then discuss the key features of the chronic inflammation seen in chronic diseases.
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Affiliation(s)
- Ichiro Manabe
- Department of Cardiovascular Medicine and Global COE, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
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1446
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Abstract
This paper presents emerging evidence linking visceral adiposity and the metabolic syndrome (MetSyn) with carcinogenesis. The link between obesity and cancer has been clearly identified in a multitude of robust epidemiological studies. Research is now focusing on the role of visceral adipose tissue in carcinogenesis; as it is recognised as an important metabolic tissue that secretes factors that systemically alter the immunological, metabolic and endocrine milieu. Excess visceral adipose tissue gives rise to a state of chronic systemic inflammation with associated insulin resistance and dysmetabolism, collectively known as the MetSyn. Prospective cohort studies have shown associations between visceral adiposity, the MetSyn and increased risk of breast cancer, colorectal cancer and oesophageal adenocarcinoma. Furthermore, visceral adiposity and the MetSyn have been associated with increased tumour progression and reduced survival. The mechanisms by which visceral adiposity and the MetSyn are thought to promote tumorigenesis are manifold. These include alterations in adipokine secretion and cell signalling pathways. In addition, hyperinsulinaemia, subsequent insulin resistance and stimulation of the insulin-like growth factor-1 axis have all been linked with visceral adiposity and promote tumour progression. Furthermore, the abundance of inflammatory cells in visceral adipose tissue, including macrophages and T-cells, create systemic inflammation and a pro-tumorigenic environment. It is clear from current research that excess visceral adiposity and associated dysmetabolism play a central role in the pathogenesis of certain cancer types. Further research is required to elucidate the exact mechanisms at play and identify potential targets for intervention.
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1447
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Altintas MM, Rossetti MA, Nayer B, Puig A, Zagallo P, Ortega LM, Johnson KB, McNamara G, Reiser J, Mendez AJ, Nayer A. Apoptosis, mastocytosis, and diminished adipocytokine gene expression accompany reduced epididymal fat mass in long-standing diet-induced obese mice. Lipids Health Dis 2011; 10:198. [PMID: 22051061 PMCID: PMC3229589 DOI: 10.1186/1476-511x-10-198] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2011] [Accepted: 11/03/2011] [Indexed: 01/13/2023] Open
Abstract
Background Obesity is characterized by increased cell death and inflammatory reactions in the adipose tissue. Here, we explored pathophysiological alterations taking place in the adipose tissue in long-standing obesity. In the epididymal fat of C57BL/6 mice fed a high-fat diet for 20 weeks, the prevalence and distribution of dead adipocytes (crown-like structures), mast cells (toluidine blue, mMCP6), macrophages (F4/80), and apoptotic cells (cleaved caspase-3) were measured. Moreover, gene and/or protein expression of several adipocytokines (leptin, adiponectin, TNF-α, IL-10, IL-6, MCP-1), F4/80, mMCP6, cleaved caspase-3 were determined. Results We observed that the epididymal fat mass was lower in obese than in lean mice. In obese mice, the epididymal fat mass correlated inversely with body weight and liver mass. Dead adipocytes, mast cells, macrophages, and apoptotic cells were abundant in the epididymal fat of obese mice, especially in the rostral vs. caudal zone. Accordingly, mMCP6, F4/80, and cleaved caspase-3 gene and/or protein expression was increased. Conversely, adiponectin, leptin, IL-6, and MCP-1 gene expression levels were lower in the epididymal fat of obese than lean mice. Although TNF-α and IL-10 gene expression was higher in the epididymal fat of obese mice, their expression relative to F4/80 and mMCP6 expression were lower in the heavily infiltrated rostral than caudal zone. Conclusions This study demonstrates that in mice with long-standing obesity diminished gene expression of several adipocytokines accompany apoptosis and reduced mass of the epididymal fat. Our findings suggest that this is due to both increased prevalence of dead adipocytes and altered immune cell activity. Differential distribution of metabolically challenged adipocytes is indicative of the presence of biologically diverse zones within the epididymal fat.
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Affiliation(s)
- Mehmet M Altintas
- Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL, USA
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1448
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Tsui H, Paltser G, Chan Y, Dorfman R, Dosch HM. 'Sensing' the link between type 1 and type 2 diabetes. Diabetes Metab Res Rev 2011; 27:913-8. [PMID: 22069284 DOI: 10.1002/dmrr.1279] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Obesity-associated insulin resistance is a core element of metabolic syndrome and type 2 diabetes (T2D). Notably, insulin resistance is also a feature of type 1 diabetes (T1D), where findings in the non-obese diabetic mouse model have implicated transient receptor potential vanilloid-1 (TRPV1+) sensory neurons in local islet inflammation and glucose metabolism. Here, we briefly review the role of TRPV1 in non-obese diabetic (NOD) T1D pathogenesis, highlighting commonalities that suggest TRPV1 may contribute to obesity and T2D as well. With the recently discovered importance of adipose infiltrating lymphocytes in the metabolic disturbances of obesity and T2D, sensory innervation of fat may thus play an analogous role to sensory neurons in the islet--modulating neuroendocrine homeostasis and inflammation. In such a scenario, TRPV1+ sensory nerves would provide the pathoaetiological link connecting the shared metabolic and immunologic features of type 1 diabetes and T2D.
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Affiliation(s)
- Hubert Tsui
- The Research Institute, Hospital For Sick Children, University of Toronto, Neuroscience and Mental Health Program, Toronto, ON M5G 1X8, Canada.
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1449
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Abstract
Mast cells are essential in allergic responses and beyond. White adipose tissue from obese humans contains large numbers of mast cells. Serum mast cell tryptase levels are also significantly higher in obese subjects than in lean subjects, suggesting a role of these inflammatory cells in obesity and diabetes. Two types of mast cell-deficient mice, along with corresponding wild-type control mice, were fed a Western diet to induce obesity and diabetes. We also used two anti-allergy drugs, cromolyn and ketotifen (Zaditor), to treat wild-type mice during intake of a Western diet or after the onset of obesity and diabetes, to examine the possible prevention or reversal of these conditions. Mast cell deficiency or pharmacological stabilization reduced body weight gain and improved glucose and insulin sensitivities. These common, side effect-free drugs also reduced pre-established obesity and diabetes without noticeable toxicity. Mechanistic studies suggest that mast cells participate in these metabolic disorders by affecting energy expenditure, protease expression, angiogenesis, apoptosis, and preadipocyte differentiation. These observations open a new era of basic research regarding mast cells, and offer hope to patients suffering from these metabolic disorders.
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Affiliation(s)
- Jing Wang
- Cardiovascular Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, USA
| | - Guo-Ping Shi
- Cardiovascular Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, USA
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1450
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Eller K, Kirsch A, Wolf AM, Sopper S, Tagwerker A, Stanzl U, Wolf D, Patsch W, Rosenkranz AR, Eller P. Potential role of regulatory T cells in reversing obesity-linked insulin resistance and diabetic nephropathy. Diabetes 2011; 60:2954-62. [PMID: 21911743 PMCID: PMC3198056 DOI: 10.2337/db11-0358] [Citation(s) in RCA: 238] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE To assess the potential role of FoxP3-expressing regulatory T cells (Tregs) in reversing obesity-linked insulin resistance and diabetic nephropathy in rodent models and humans. RESEARCH DESIGN AND METHODS To characterize the role of Tregs in insulin resistance, human visceral adipose tissue was first evaluated for Treg infiltration and second, the db/db mouse model was evaluated. RESULTS Obese patients with insulin resistance displayed significantly decreased natural Tregs but an increase in adaptive Tregs in their visceral adipose tissue as compared with lean control subjects. To further evaluate the pathogenic role of Tregs in insulin resistance, the db/db mouse model was used. Treg depletion using an anti-CD25 monoclonal antibody enhanced insulin resistance as shown by increased fasting blood glucose levels as well as an impaired insulin sensitivity. Moreover, Treg-depleted db/db mice developed increased signs of diabetic nephropathy, such as albuminuria and glomerular hyperfiltration. This was paralleled by a proinflammatory milieu in both murine visceral adipose tissue and the kidney. Conversely, adoptive transfer of CD4(+)FoxP3(+) Tregs significantly improved insulin sensitivity and diabetic nephropathy. Accordingly, there was increased mRNA expression of FoxP3 as well as less abundant proinflammatory CD8(+)CD69(+) T cells in visceral adipose tissue and kidneys of Treg-treated animals. CONCLUSIONS Data suggest a potential therapeutic value of Tregs to improve insulin resistance and end organ damage in type 2 diabetes by limiting the proinflammatory milieu.
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Affiliation(s)
- Kathrin Eller
- Clinical Division of Nephrology, Department of Internal Medicine, Medical University Graz, Graz, Austria.
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