1
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Li B, Sun S, Li JJ, Yuan JP, Sun SR, Wu Q. Adipose tissue macrophages: implications for obesity-associated cancer. Mil Med Res 2023; 10:1. [PMID: 36593475 PMCID: PMC9809128 DOI: 10.1186/s40779-022-00437-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 12/12/2022] [Indexed: 01/04/2023] Open
Abstract
Obesity is one of the most serious global health problems, with an incidence that increases yearly and coincides with the development of cancer. Adipose tissue macrophages (ATMs) are particularly important in this context and contribute to linking obesity-related inflammation and tumor progression. However, the functions of ATMs on the progression of obesity-associated cancer remain unclear. In this review, we describe the origins, phenotypes, and functions of ATMs. Subsequently, we summarize the potential mechanisms on the reprogramming of ATMs in the obesity-associated microenvironment, including the direct exchange of dysfunctional metabolites, inordinate cytokines and other signaling mediators, transfer of extracellular vesicle cargo, and variations in the gut microbiota and its metabolites. A better understanding of the properties and functions of ATMs under conditions of obesity will lead to the development of new therapeutic interventions for obesity-related cancer.
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Affiliation(s)
- Bei Li
- Department of Pathology, Renmin Hospital of Wuhan University, Wuhan, 430060, China
| | - Si Sun
- Department of Clinical Laboratory, Renmin Hospital of Wuhan University, Wuhan, 430060, China
| | - Juan-Juan Li
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, Wuhan, 430060, China
| | - Jing-Ping Yuan
- Department of Pathology, Renmin Hospital of Wuhan University, Wuhan, 430060, China
| | - Sheng-Rong Sun
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, Wuhan, 430060, China.
| | - Qi Wu
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, Wuhan, 430060, China. .,Tongji University Cancer Center, Shanghai Tenth People's Hospital of Tongji University, School of Medicine, Tongji University, Shanghai, 200092, China.
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2
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Wang Y, Hu C. Leptin and Asthma: What Are the Interactive Correlations? Biomolecules 2022; 12:biom12121780. [PMID: 36551211 PMCID: PMC9775505 DOI: 10.3390/biom12121780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 11/25/2022] [Accepted: 11/28/2022] [Indexed: 12/02/2022] Open
Abstract
Leptin is an adipokine directly correlated with the proinflammatory obese-associated phenotype. Leptin has been demonstrated to inhibit adipogenesis, promote fat demarcation, promote a chronic inflammatory state, increase insulin sensitivity, and promote angiogenesis. Leptin, a regulator of the immune response, is implicated in the pathology of asthma. Studies involved in the key cell reaction and animal models of asthma have provided vital insights into the proinflammatory role of leptin in asthma. Many studies described the immune cell and related cellular pathways activated by leptin, which are beneficial in asthma development and increasing exacerbations. Subsequent studies relating to animal models support the role of leptin in increasing inflammatory cell infiltration, airway hyperresponsiveness, and inflammatory responses. However, the conclusive effects of leptin in asthma are not well elaborated. In the present study, we explored the general functions and the clinical cohort study supporting the association between leptin and asthma. The main objective of our review is to address the knowns and unknowns of leptin on asthma. In this perspective, the arguments about the different faces of leptin in asthma are provided to picture the potential directions, thus yielding a better understanding of asthma development.
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Affiliation(s)
- Yang Wang
- Department of Respiratory Medicine (Department of Respiratory and Critical Care Medicine), Xiangya Hospital, Central South University, Changsha 410008, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Chengping Hu
- Department of Respiratory Medicine (Department of Respiratory and Critical Care Medicine), Xiangya Hospital, Central South University, Changsha 410008, China
- Correspondence:
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3
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Monteiro LDB, Prodonoff JS, Favero de Aguiar C, Correa-da-Silva F, Castoldi A, Bakker NVT, Davanzo GG, Castelucci B, Pereira JADS, Curtis J, Büscher J, Reis LMD, Castro G, Ribeiro G, Virgílio-da-Silva JV, Adamoski D, Dias SMG, Consonni SR, Donato J, Pearce EJ, Câmara NOS, Moraes-Vieira PM. Leptin Signaling Suppression in Macrophages Improves Immunometabolic Outcomes in Obesity. Diabetes 2022; 71:1546-1561. [PMID: 35377454 DOI: 10.2337/db21-0842] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 03/13/2022] [Indexed: 11/13/2022]
Abstract
Obesity is a major concern for global health care systems. Systemic low-grade inflammation in obesity is a major risk factor for insulin resistance. Leptin is an adipokine secreted by the adipose tissue that functions by controlling food intake, leading to satiety. Leptin levels are increased in obesity. Here, we show that leptin enhances the effects of LPS in macrophages, intensifying the production of cytokines, glycolytic rates, and morphological and functional changes in the mitochondria through an mTORC2-dependent, mTORC1-independent mechanism. Leptin also boosts the effects of IL-4 in macrophages, leading to increased oxygen consumption, expression of macrophage markers associated with a tissue repair phenotype, and wound healing. In vivo, hyperleptinemia caused by diet-induced obesity increases the inflammatory response by macrophages. Deletion of leptin receptor and subsequently of leptin signaling in myeloid cells (ObR-/-) is sufficient to improve insulin resistance in obese mice and decrease systemic inflammation. Our results indicate that leptin acts as a systemic nutritional checkpoint to regulate macrophage fitness and contributes to obesity-induced inflammation and insulin resistance. Thus, specific interventions aimed at downstream modulators of leptin signaling may represent new therapeutic targets to treat obesity-induced systemic inflammation.
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Affiliation(s)
- Lauar de Brito Monteiro
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas, Brazil
| | - Juliana Silveira Prodonoff
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas, Brazil
| | - Cristhiane Favero de Aguiar
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas, Brazil
| | - Felipe Correa-da-Silva
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas, Brazil
| | - Angela Castoldi
- Laboratory Keizo Asami, Immunopathology Laboratory, Federal University of Pernambuco, Pernambuco, Brazil
| | - Nikki van Teijlingen Bakker
- Department of Immunometabolism, Max Planck Institute of Epigenetics and Immunobiology, Freiburg im Breisgau, Germany
| | - Gustavo Gastão Davanzo
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas, Brazil
| | - Bianca Castelucci
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas, Brazil
| | - Jéssica Aparecida da Silva Pereira
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas, Brazil
- Department of Immunology, Institute of Biomedical Sciences IV, University of São Paulo, São Paulo, Brazil
| | - Jonathan Curtis
- Department of Immunometabolism, Max Planck Institute of Epigenetics and Immunobiology, Freiburg im Breisgau, Germany
- Bloomberg Kimmel Institute and Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Jörg Büscher
- Department of Immunometabolism, Max Planck Institute of Epigenetics and Immunobiology, Freiburg im Breisgau, Germany
| | - Larissa Menezes Dos Reis
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas, Brazil
| | - Gisele Castro
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas, Brazil
| | - Guilherme Ribeiro
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas, Brazil
| | - João Victor Virgílio-da-Silva
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas, Brazil
| | - Douglas Adamoski
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, Brazil
| | - Sandra Martha Gomes Dias
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, Brazil
| | - Silvio Roberto Consonni
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas, Campinas, Brazil
| | - Jose Donato
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Edward J Pearce
- Department of Immunometabolism, Max Planck Institute of Epigenetics and Immunobiology, Freiburg im Breisgau, Germany
- Bloomberg Kimmel Institute and Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Niels Olsen Saraiva Câmara
- Department of Immunology, Institute of Biomedical Sciences IV, University of São Paulo, São Paulo, Brazil
| | - Pedro M Moraes-Vieira
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas, Brazil
- Experimental Medicine Research Cluster, University of Campinas, São Paulo, Brazil
- Obesity and Comorbidities Research Center, University of Campinas, São Paulo, Brazil
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4
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Ren Y, Zhao H, Yin C, Lan X, Wu L, Du X, Griffiths HR, Gao D. Adipokines, Hepatokines and Myokines: Focus on Their Role and Molecular Mechanisms in Adipose Tissue Inflammation. Front Endocrinol (Lausanne) 2022; 13:873699. [PMID: 35909571 PMCID: PMC9329830 DOI: 10.3389/fendo.2022.873699] [Citation(s) in RCA: 51] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 06/17/2022] [Indexed: 11/18/2022] Open
Abstract
Chronic low-grade inflammation in adipose tissue (AT) is a hallmark of obesity and contributes to various metabolic disorders, such as type 2 diabetes and cardiovascular diseases. Inflammation in ATs is characterized by macrophage infiltration and the activation of inflammatory pathways mediated by NF-κB, JNK, and NLRP3 inflammasomes. Adipokines, hepatokines and myokines - proteins secreted from AT, the liver and skeletal muscle play regulatory roles in AT inflammation via endocrine, paracrine, and autocrine pathways. For example, obesity is associated with elevated levels of pro-inflammatory adipokines (e.g., leptin, resistin, chemerin, progranulin, RBP4, WISP1, FABP4, PAI-1, Follistatin-like1, MCP-1, SPARC, SPARCL1, and SAA) and reduced levels of anti-inflammatory adipokines such as adiponectin, omentin, ZAG, SFRP5, CTRP3, vaspin, and IL-10. Moreover, some hepatokines (Fetuin A, DPP4, FGF21, GDF15, and MANF) and myokines (irisin, IL-6, and DEL-1) also play pro- or anti-inflammatory roles in AT inflammation. This review aims to provide an updated understanding of these organokines and their role in AT inflammation and related metabolic abnormalities. It serves to highlight the molecular mechanisms underlying the effects of these organokines and their clinical significance. Insights into the roles and mechanisms of these organokines could provide novel and potential therapeutic targets for obesity-induced inflammation.
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Affiliation(s)
- Yakun Ren
- Institute of Molecular and Translational Medicine, Xian Jiaotong University Health Science Center, Xi’an, China
| | - Hao Zhao
- School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
| | - Chunyan Yin
- Department of Pediatrics, The Second Affiliated Hospital of Xi’an Jiaotong University, Xi’an, China
| | - Xi Lan
- Institute of Molecular and Translational Medicine, Xian Jiaotong University Health Science Center, Xi’an, China
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
| | - Litao Wu
- Institute of Molecular and Translational Medicine, Xian Jiaotong University Health Science Center, Xi’an, China
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
| | - Xiaojuan Du
- Institute of Molecular and Translational Medicine, Xian Jiaotong University Health Science Center, Xi’an, China
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
| | - Helen R. Griffiths
- Swansea University Medical School, Swansea University, Swansea, United Kingdom
| | - Dan Gao
- Institute of Molecular and Translational Medicine, Xian Jiaotong University Health Science Center, Xi’an, China
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Center, Xi’an, China
- *Correspondence: Dan Gao,
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5
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Batty MJ, Chabrier G, Sheridan A, Gage MC. Metabolic Hormones Modulate Macrophage Inflammatory Responses. Cancers (Basel) 2021; 13:cancers13184661. [PMID: 34572888 PMCID: PMC8467249 DOI: 10.3390/cancers13184661] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 08/31/2021] [Accepted: 09/13/2021] [Indexed: 12/17/2022] Open
Abstract
Simple Summary Macrophages are a type of immune cell which play an important role in the development of cancer. Obesity increases the risk of cancer and obesity also causes disruption to the normal levels of hormones that are produced to coordinate metabolism. Recent research now shows that these metabolic hormones also play important roles in macrophage immune responses and so through macrophages, disrupted metabolic hormone levels may promote cancer. This review article aims to highlight and summarise these recent findings so that the scientific community may better understand how important this new area of research is, and how these findings can be capitalised on for future scientific studies. Abstract Macrophages are phagocytotic leukocytes that play an important role in the innate immune response and have established roles in metabolic diseases and cancer progression. Increased adiposity in obese individuals leads to dysregulation of many hormones including those whose functions are to coordinate metabolism. Recent evidence suggests additional roles of these metabolic hormones in modulating macrophage inflammatory responses. In this review, we highlight key metabolic hormones and summarise their influence on the inflammatory response of macrophages and consider how, in turn, these hormones may influence the development of different cancer types through the modulation of macrophage functions.
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6
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Beak SH, Baik M. Comparison of transcriptome between high- and low-marbling fineness in longissimus thoracis muscle of Korean cattle. Anim Biosci 2021; 35:196-203. [PMID: 34293845 PMCID: PMC8738949 DOI: 10.5713/ab.21.0150] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 06/11/2021] [Indexed: 11/27/2022] Open
Abstract
Objective This study compared differentially expressed genes (DEGs) between groups with high and low numbers of fine marbling particles (NFMP) in the longissimus thoracis muscle (LT) of Korean cattle to understand the molecular events associated with fine marbling particle formation. Methods The size and distribution of marbling particles in the LT were assessed with a computer image analysis method. Based on the NFMP, 10 LT samples were selected and assigned to either high- (n = 5) or low- (n = 5) NFMP groups. Using RNA sequencing, LT transcriptomic profiles were compared between the high- and low-NFMP groups. DEGs were selected at p<0.05 and |fold change| >2 and subjected to functional annotation. Results In total, 328 DEGs were identified, with 207 up-regulated and 121 down-regulated genes in the high-NFMP group. Pathway analysis of these DEGs revealed five significant (p<0.05) Kyoto encyclopedia of genes and genomes pathways; the significant terms included endocytosis (p = 0.023), protein processing in endoplasmic reticulum (p = 0.019), and adipocytokine signaling pathway (p = 0.024), which are thought to regulate adipocyte hypertrophy and hyperplasia. The expression of sirtuin4 (p<0.001) and insulin receptor substrate 2 (p = 0.043), which are associated with glucose uptake and adipocyte differentiation, was higher in the high-NFMP group than in the low-NFMP group. Conclusion Transcriptome differences between the high- and low-NFMP groups suggest that pathways regulating adipocyte hyperplasia and hypertrophy are involved in the marbling fineness of the LT.
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Affiliation(s)
- Seok-Hyeon Beak
- Department of Agricultural Biotechnology and Research Institute of Agriculture and Life Sciences, College of Agriculture and Life Science, Seoul National University, Seoul 08826, Korea
| | - Myunggi Baik
- Department of Agricultural Biotechnology and Research Institute of Agriculture and Life Sciences, College of Agriculture and Life Science, Seoul National University, Seoul 08826, Korea.,Institue of Green Bio Science and Technology, Seoul National University, Pyeongchang 25354, Korea
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7
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Souza-Almeida G, Palhinha L, Liechocki S, da Silva Pereira JA, Reis PA, Dib PRB, Hottz ED, Gameiro J, Vallochi AL, de Almeida CJ, Castro-Faria-Neto H, Bozza PT, Maya-Monteiro CM. Peripheral leptin signaling persists in innate immune cells during diet-induced obesity. J Leukoc Biol 2021; 109:1131-1138. [PMID: 33070353 DOI: 10.1002/jlb.3ab0820-092rr] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 08/29/2020] [Accepted: 09/01/2020] [Indexed: 01/13/2023] Open
Abstract
Leptin is a pleiotropic adipokine that regulates immunometabolism centrally and peripherally. Obese individuals present increased levels of leptin in the blood and develop hypothalamic resistance to this adipokine. Here we investigated whether leptin effects on the periphery are maintained despite the hypothalamic resistance. We previously reported that leptin injection induces in vivo neutrophil migration and peritoneal macrophage activation in lean mice through TNF-α- and CXCL1-dependent mechanisms. However, leptin effects on leukocyte biology during obesity remain unclear. In this study, we investigated the in vivo responsiveness of leukocytes to i.p. injected leptin in mice with diet-induced obesity (DIO). After 14-16 wk, high-sucrose, high-fat diet (HFD)-fed mice showed hyperglycemia, hyperleptinemia, and dyslipidemia compared to normal-sucrose, normal-fat diet (ND). Exogenous leptin did not reduce food intake in DIO mice in contrast to control mice, indicating that DIO mice were centrally resistant to leptin. Regardless of the diet, we found increased levels of TNF-α and CXCL1 in the animals injected with leptin, alongside a pronounced neutrophil migration to the peritoneal cavity and enhanced biogenesis of lipid droplets in peritoneal macrophages. Supporting our in vivo results, data from ex vivo leptin stimulation experiments confirmed hypothalamic resistance in DIO mice, whereas bone marrow cells responded to leptin stimulation through mTOR signaling despite obesity. Altogether, our results show that leukocytes responded equally to leptin in ND- or HFD-fed mice. These results support a role for leptin in the innate immune response also in obesity, contributing to the inflammatory status that leads to the development of metabolic disease.
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Affiliation(s)
- Glaucia Souza-Almeida
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Rio de Janeiro, Brazil
- Current address: Laboratory of Immunoinflammation, Department of Genetics, Evolution, Microbiology, and Immunology, Institute of Biology, University of Campinas, Campinas, Sao Paulo, Brazil
| | - Lohanna Palhinha
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Rio de Janeiro, Brazil
| | - Sally Liechocki
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Patrícia Alves Reis
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Rio de Janeiro, Brazil
| | - Paula Ribeiro Braga Dib
- Laboratory of Immunothrombosis, Department of Biochemistry, Federal University of Juiz de Fora, Juiz de Fora, Minas Gerais, Brazil
- Laboratory of Immunology, Infectious Disease and Obesity, Department of Parasitology, Microbiology and Immunology, Federal University of Juiz de Fora, Juiz de Fora, Minas Gerais, Brazil
| | - Eugenio D Hottz
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Rio de Janeiro, Brazil
- Laboratory of Immunothrombosis, Department of Biochemistry, Federal University of Juiz de Fora, Juiz de Fora, Minas Gerais, Brazil
| | - Jacy Gameiro
- Laboratory of Immunology, Infectious Disease and Obesity, Department of Parasitology, Microbiology and Immunology, Federal University of Juiz de Fora, Juiz de Fora, Minas Gerais, Brazil
| | - Adriana Lima Vallochi
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Rio de Janeiro, Brazil
| | - Cecília Jacques de Almeida
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Rio de Janeiro, Brazil
| | - Hugo Castro-Faria-Neto
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Rio de Janeiro, Brazil
| | - Patrícia T Bozza
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Rio de Janeiro, Brazil
| | - Clarissa Menezes Maya-Monteiro
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Rio de Janeiro, Brazil
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8
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de Candia P, Prattichizzo F, Garavelli S, Alviggi C, La Cava A, Matarese G. The pleiotropic roles of leptin in metabolism, immunity, and cancer. J Exp Med 2021; 218:211994. [PMID: 33857282 PMCID: PMC8056770 DOI: 10.1084/jem.20191593] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 03/10/2021] [Accepted: 03/11/2021] [Indexed: 12/11/2022] Open
Abstract
The discovery of the archetypal adipocytokine leptin and how it regulates energy homeostasis have represented breakthroughs in our understanding of the endocrine function of the adipose tissue and the biological determinants of human obesity. Investigations on leptin have also been instrumental in identifying physio-pathological connections between metabolic regulation and multiple immunological functions. For example, the description of the promoting activities of leptin on inflammation and cell proliferation have recognized the detrimental effects of leptin in connecting dysmetabolic conditions with cancer and with onset and/or progression of autoimmune disease. Here we review the multiple biological functions and complex framework of operations of leptin, discussing why and how the pleiotropic activities of this adipocytokine still pose major hurdles in the development of effective leptin-based therapeutic opportunities for different clinical conditions.
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Affiliation(s)
- Paola de Candia
- Istituto di Ricovero e Cura a Carattere Scientifico MultiMedica, Milan, Italy
| | | | - Silvia Garavelli
- Istituto per l'Endocrinologia e l'Oncologia Sperimentale, Consiglio Nazionale delle Ricerche, Naples, Italy
| | - Carlo Alviggi
- Department of Neuroscience, Reproductive Science and Odontostomatology, Università di Napoli "Federico II," Naples, Italy
| | - Antonio La Cava
- Department of Medicine, University of California, Los Angeles, Los Angeles, CA
| | - Giuseppe Matarese
- Istituto per l'Endocrinologia e l'Oncologia Sperimentale, Consiglio Nazionale delle Ricerche, Naples, Italy.,T reg Cell Lab, Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università di Napoli "Federico II," Naples, Italy
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9
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Conte M, Santoro A, Collura S, Martucci M, Battista G, Bazzocchi A, Morsiani C, Sevini F, Capri M, Monti D, Franceschi C, Salvioli S. Circulating perilipin 2 levels are associated with fat mass, inflammatory and metabolic markers and are higher in women than men. Aging (Albany NY) 2021; 13:7931-7942. [PMID: 33735111 PMCID: PMC8034884 DOI: 10.18632/aging.202840] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 03/04/2021] [Indexed: 02/06/2023]
Abstract
Perilipin 2 (PLIN2) is a protein involved in lipid storage and metabolism in non-adipose tissues. Detectable levels of circulating PLIN2 (cPLIN2) have been reported to be associated with some types of cancer, but no systematic analysis of age-related modifications in cPLIN2 levels has ever been performed. We measured serum cPLIN2 in a group of old people including centenarians in comparison with young subjects and tested possible correlations with parameters of body composition, fat and glucose metabolism, and inflammation. We found that: i. levels of cPLIN2 do not change with age, but women have higher levels of cPLIN2 with respect to men; ii. cPLIN2 levels strongly correlate to BMI, as well as fat and lean mass; iii. cPLIN2 levels strongly correlate with the proinflammatory adipokine leptin. Due to the adipogenic activity of leptin, it is hypothesized that cPLIN2 is affected and possibly regulated by this pleiotropic adipokine. Moreover, these results suggest that cPLIN2 (possibly together with leptin) could be assumed as a proxy for body adiposity.
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Affiliation(s)
- Maria Conte
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), University of Bologna, Bologna, Italy.,Interdepartmental Center "Alma Mater Research Institute on Global Challenges and Climate Change (Alma Climate)", University of Bologna, Bologna, Italy
| | - Aurelia Santoro
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), University of Bologna, Bologna, Italy
| | - Salvatore Collura
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), University of Bologna, Bologna, Italy
| | - Morena Martucci
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), University of Bologna, Bologna, Italy
| | - Giuseppe Battista
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), University of Bologna, Bologna, Italy
| | - Alberto Bazzocchi
- Diagnostic and Interventional Radiology, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
| | - Cristina Morsiani
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), University of Bologna, Bologna, Italy
| | - Federica Sevini
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), University of Bologna, Bologna, Italy
| | - Miriam Capri
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), University of Bologna, Bologna, Italy.,Interdepartmental Center "Alma Mater Research Institute on Global Challenges and Climate Change (Alma Climate)", University of Bologna, Bologna, Italy
| | - Daniela Monti
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, Italy
| | - Claudio Franceschi
- Laboratory of Systems Medicine of Healthy Aging and Department of Applied Mathematics, Lobachevsky University, Nizhny Novgorod, Russia
| | - Stefano Salvioli
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), University of Bologna, Bologna, Italy.,Interdepartmental Center "Alma Mater Research Institute on Global Challenges and Climate Change (Alma Climate)", University of Bologna, Bologna, Italy
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10
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Cordero-Barreal A, González-Rodríguez M, Ruiz-Fernández C, Eldjoudi DA, AbdElHafez YRF, Lago F, Conde J, Gómez R, González-Gay MA, Mobasheri A, Pino J, Gualillo O. An Update on the Role of Leptin in the Immuno-Metabolism of Cartilage. Int J Mol Sci 2021; 22:ijms22052411. [PMID: 33673730 PMCID: PMC7957536 DOI: 10.3390/ijms22052411] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 02/20/2021] [Accepted: 02/25/2021] [Indexed: 12/14/2022] Open
Abstract
Since its discovery in 1994, leptin has been considered as an adipokine with pleiotropic effects. In this review, we summarize the actual information about the impact of this hormone on cartilage metabolism and pathology. Leptin signalling depends on the interaction with leptin receptor LEPR, being the long isoform of the receptor (LEPRb) the one with more efficient intracellular signalling. Chondrocytes express the long isoform of the leptin receptor and in these cells, leptin signalling, alone or in combination with other molecules, induces the expression of pro-inflammatory molecules and cartilage degenerative enzymes. Leptin has been shown to increase the proliferation and activation of immune cells, increasing the severity of immune degenerative cartilage diseases. Leptin expression in serum and synovial fluid are related to degenerative diseases such as osteoarthritis (OA), rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). Inhibition of leptin signalling showed to have protective effects in these diseases showing the key role of leptin in cartilage degeneration.
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Affiliation(s)
- Alfonso Cordero-Barreal
- SERGAS (Servizo Galego de Saude) and IDIS (Instituto de Investigación Sanitaria de Santiago), The NEIRID Group (Neuroendocrine Interactions in Rheumatology and Inflammatory Diseases), Santiago University Clinical Hospital, Building C, Travesía da Choupana S/N, 15706 Santiago de Compostela, Spain; (A.C.-B.); (M.G.-R.); (C.R.-F.); (D.A.E.); (Y.R.F.A.)
| | - María González-Rodríguez
- SERGAS (Servizo Galego de Saude) and IDIS (Instituto de Investigación Sanitaria de Santiago), The NEIRID Group (Neuroendocrine Interactions in Rheumatology and Inflammatory Diseases), Santiago University Clinical Hospital, Building C, Travesía da Choupana S/N, 15706 Santiago de Compostela, Spain; (A.C.-B.); (M.G.-R.); (C.R.-F.); (D.A.E.); (Y.R.F.A.)
| | - Clara Ruiz-Fernández
- SERGAS (Servizo Galego de Saude) and IDIS (Instituto de Investigación Sanitaria de Santiago), The NEIRID Group (Neuroendocrine Interactions in Rheumatology and Inflammatory Diseases), Santiago University Clinical Hospital, Building C, Travesía da Choupana S/N, 15706 Santiago de Compostela, Spain; (A.C.-B.); (M.G.-R.); (C.R.-F.); (D.A.E.); (Y.R.F.A.)
| | - Djedjiga Ait Eldjoudi
- SERGAS (Servizo Galego de Saude) and IDIS (Instituto de Investigación Sanitaria de Santiago), The NEIRID Group (Neuroendocrine Interactions in Rheumatology and Inflammatory Diseases), Santiago University Clinical Hospital, Building C, Travesía da Choupana S/N, 15706 Santiago de Compostela, Spain; (A.C.-B.); (M.G.-R.); (C.R.-F.); (D.A.E.); (Y.R.F.A.)
| | - Yousof Ramadan Farrag AbdElHafez
- SERGAS (Servizo Galego de Saude) and IDIS (Instituto de Investigación Sanitaria de Santiago), The NEIRID Group (Neuroendocrine Interactions in Rheumatology and Inflammatory Diseases), Santiago University Clinical Hospital, Building C, Travesía da Choupana S/N, 15706 Santiago de Compostela, Spain; (A.C.-B.); (M.G.-R.); (C.R.-F.); (D.A.E.); (Y.R.F.A.)
| | - Francisca Lago
- Molecular and Cellular Cardiology Group, SERGAS (Servizo Galego de Saude) and IDIS (Instituto de Investigación Sanitaria de Santiago), Research Laboratory 7, Santiago University Clinical Hospital, 15706 Santiago de Compostela, Spain; (F.L.); (J.C.)
| | - Javier Conde
- Molecular and Cellular Cardiology Group, SERGAS (Servizo Galego de Saude) and IDIS (Instituto de Investigación Sanitaria de Santiago), Research Laboratory 7, Santiago University Clinical Hospital, 15706 Santiago de Compostela, Spain; (F.L.); (J.C.)
| | - Rodolfo Gómez
- SERGAS (Servizo Galego de Saude) and IDIS (Instituto de Investigación Sanitaria de Santiago), The Muscle-Skeletal Pathology Group, Santiago University Clinical Hospital, Building C, Travesía da Choupana S/N, 15706 Santiago de Compostela, Spain;
| | - Miguel Angel González-Gay
- Epidemiology, Genetics and Atherosclerosis Research Group on Systemic Inflammatory Diseases, Universidad de Cantabria and IDIVAL, Hospital Universitario Marqués de Valdecilla, Av. Valdecilla, 39008 Santander, Spain;
| | - Ali Mobasheri
- Research Unit of Medical Imaging, Physics and Technology, Faculty of Medicine, University of Oulu, FIN-90230 Oulu, Finland;
- Department of Regenerative Medicine, State Research Institute, Centre for Innovative Medicine, LT-08406 Vilnius, Lithuania
- Departments of Orthopedics, Rheumatology and Clinical Immunology, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands
- Department of Joint Surgery, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China
| | - Jesus Pino
- SERGAS (Servizo Galego de Saude) and IDIS (Instituto de Investigación Sanitaria de Santiago), The NEIRID Group (Neuroendocrine Interactions in Rheumatology and Inflammatory Diseases), Santiago University Clinical Hospital, Building C, Travesía da Choupana S/N, 15706 Santiago de Compostela, Spain; (A.C.-B.); (M.G.-R.); (C.R.-F.); (D.A.E.); (Y.R.F.A.)
- Correspondence: (J.P.); (O.G.); Tel./Fax: +34-981950905 (O.G.)
| | - Oreste Gualillo
- SERGAS (Servizo Galego de Saude) and IDIS (Instituto de Investigación Sanitaria de Santiago), The NEIRID Group (Neuroendocrine Interactions in Rheumatology and Inflammatory Diseases), Santiago University Clinical Hospital, Building C, Travesía da Choupana S/N, 15706 Santiago de Compostela, Spain; (A.C.-B.); (M.G.-R.); (C.R.-F.); (D.A.E.); (Y.R.F.A.)
- Correspondence: (J.P.); (O.G.); Tel./Fax: +34-981950905 (O.G.)
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11
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Ganguly R, Khanal S, Mathias A, Gupta S, Lallo J, Sahu S, Ohanyan V, Patel A, Storm K, Datta S, Raman P. TSP-1 (Thrombospondin-1) Deficiency Protects ApoE -/- Mice Against Leptin-Induced Atherosclerosis. Arterioscler Thromb Vasc Biol 2021; 41:e112-e127. [PMID: 33327743 PMCID: PMC8105272 DOI: 10.1161/atvbaha.120.314962] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
OBJECTIVE Hyperleptinemia, hallmark of obesity, is a putative pathophysiologic trigger for atherosclerosis. We previously reported a stimulatory effect of leptin on TSP-1 (thrombospondin-1) expression, a proatherogenic matricellular protein implicated in atherogenesis. However, a causal role of TSP-1 in leptin-driven atherosclerosis remains unknown. Approach and Results: Seventeen-weeks-old ApoE-/- and TSP-1-/-/ApoE-/- double knockout mice, on normocholesterolemic diet, were treated with or without murine recombinant leptin (5 µg/g bwt, IP) once daily for 3 weeks. Using aortic root morphometry and en face lesion assay, we found that TSP-1 deletion abrogated leptin-stimulated lipid-filled lesion burden, plaque area, and collagen accumulation in aortic roots of ApoE-/- mice, shown via Oil red O, hematoxylin and eosin, and Masson trichrome staining, respectively. Immunofluorescence microscopy of aortic roots showed that TSP-1 deficiency blocked leptin-induced inflammatory and smooth muscle cell abundance as well as cellular proliferation in ApoE-/- mice. Moreover, these effects were concomitant to changes in VLDL (very low-density lipoprotein)-triglyceride and HDL (high-density lipoprotein)-cholesterol levels. Immunoblotting further revealed reduced vimentin and pCREB (phospho-cyclic AMP response element-binding protein) accompanied with augmented smooth muscle-myosin heavy chain expression in aortic vessels of leptin-treated double knockout versus leptin-treated ApoE-/-; also confirmed in aortic smooth muscle cells from the mice genotypes, incubated ± leptin in vitro. Finally, TSP-1 deletion impeded plaque burden in leptin-treated ApoE-/- on western diet, independent of plasma lipid alterations. CONCLUSIONS The present study provides evidence for a protective effect of TSP-1 deletion on leptin-stimulated atherogenesis. Our findings suggest a regulatory role of TSP-1 on leptin-induced vascular smooth muscle cell phenotypic transition and inflammatory lesion invasion. Collectively, these results underscore TSP-1 as a potential target of leptin-induced vasculopathy.
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MESH Headings
- Animals
- Aorta/metabolism
- Aorta/pathology
- Aortic Diseases/chemically induced
- Aortic Diseases/metabolism
- Aortic Diseases/pathology
- Aortic Diseases/prevention & control
- Atherosclerosis/chemically induced
- Atherosclerosis/metabolism
- Atherosclerosis/pathology
- Atherosclerosis/prevention & control
- Cell Differentiation
- Cell Proliferation
- Cells, Cultured
- Collagen/metabolism
- Diet, High-Fat
- Disease Models, Animal
- Leptin
- Male
- Mice, Inbred C57BL
- Mice, Knockout, ApoE
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/pathology
- Myocytes, Smooth Muscle/metabolism
- Myocytes, Smooth Muscle/pathology
- Plaque, Atherosclerotic
- Signal Transduction
- Thrombospondin 1/deficiency
- Thrombospondin 1/genetics
- Mice
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Affiliation(s)
- Rituparna Ganguly
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH
- School of Biomedical Sciences, Kent State University, Kent, OH
- Current Address: Department of Diabetes Complications and Metabolism, City of Hope, 1500 East Duarte Road, Duarte, CA 91010
| | - Saugat Khanal
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH
- School of Biomedical Sciences, Kent State University, Kent, OH
| | - Amy Mathias
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH
| | - Shreya Gupta
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH
- School of Biomedical Sciences, Kent State University, Kent, OH
| | - Jason Lallo
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH
| | - Soumyadip Sahu
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH
- School of Biomedical Sciences, Kent State University, Kent, OH
- Current Address: National Institute of Environmental Health Sciences, Research Triangle Park, Durham, NC 27709
| | - Vahagn Ohanyan
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH
- School of Biomedical Sciences, Kent State University, Kent, OH
| | - Aakaash Patel
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH
| | - Kyle Storm
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH
| | - Sujay Datta
- Department of Statistics, The University of Akron, Akron, OH
| | - Priya Raman
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH
- School of Biomedical Sciences, Kent State University, Kent, OH
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12
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Pereira S, Cline DL, Glavas MM, Covey SD, Kieffer TJ. Tissue-Specific Effects of Leptin on Glucose and Lipid Metabolism. Endocr Rev 2021; 42:1-28. [PMID: 33150398 PMCID: PMC7846142 DOI: 10.1210/endrev/bnaa027] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Indexed: 12/18/2022]
Abstract
The discovery of leptin was intrinsically associated with its ability to regulate body weight. However, the effects of leptin are more far-reaching and include profound glucose-lowering and anti-lipogenic effects, independent of leptin's regulation of body weight. Regulation of glucose metabolism by leptin is mediated both centrally and via peripheral tissues and is influenced by the activation status of insulin signaling pathways. Ectopic fat accumulation is diminished by both central and peripheral leptin, an effect that is beneficial in obesity-associated disorders. The magnitude of leptin action depends upon the tissue, sex, and context being examined. Peripheral tissues that are of particular relevance include the endocrine pancreas, liver, skeletal muscle, adipose tissues, immune cells, and the cardiovascular system. As a result of its potent metabolic activity, leptin is used to control hyperglycemia in patients with lipodystrophy and is being explored as an adjunct to insulin in patients with type 1 diabetes. To fully understand the role of leptin in physiology and to maximize its therapeutic potential, the mechanisms of leptin action in these tissues needs to be further explored.
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Affiliation(s)
- Sandra Pereira
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, Canada
| | - Daemon L Cline
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, Canada
| | - Maria M Glavas
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, Canada
| | - Scott D Covey
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, Canada
| | - Timothy J Kieffer
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, Canada.,Department of Surgery, University of British Columbia, Vancouver, Canada.,School of Biomedical Engineering, University of British Columbia, Vancouver, Canada
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13
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Chen D, Zhang X, Li Z, Zhu B. Metabolic regulatory crosstalk between tumor microenvironment and tumor-associated macrophages. Am J Cancer Res 2021; 11:1016-1030. [PMID: 33391518 PMCID: PMC7738889 DOI: 10.7150/thno.51777] [Citation(s) in RCA: 158] [Impact Index Per Article: 52.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 10/18/2020] [Indexed: 02/06/2023] Open
Abstract
Macrophages phagocytize pathogens to initiate innate immunity and products from the tumor microenvironment (TME) to mediate tumor immunity. The loss of tumor-associated macrophage (TAM)-mediated immune responses results in immune suppression. To reverse this immune disorder, the regulatory mechanism of TAMs in the TME needs to be clarified. Immune molecules (cytokines and chemokines) from TAMs and the TME have been widely accepted as mutual mediators of signal transduction in the past few decades. Recently, researchers have tried to seek the intrinsic mechanism of TAM phenotypic and functional changes through metabolic connections. Numerous metabolites derived from the TME have been identified that induce the cell-cell crosstalk with TAMs. The bulk tumor cells, immune cells, and stromal cells produce metabolites in the TME that are involved in the metabolic regulation of TAMs. Meanwhile, some products from TAMs regulate the biological functions of the tumor as well. Here, we review the recent reports demonstrating the metabolic regulation between TME and TAMs.
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14
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Brunner JS, Vogel A, Lercher A, Caldera M, Korosec A, Pühringer M, Hofmann M, Hajto A, Kieler M, Garrido LQ, Kerndl M, Kuttke M, Mesteri I, Górna MW, Kulik M, Dominiak PM, Brandon AE, Estevez E, Egan CL, Gruber F, Schweiger M, Menche J, Bergthaler A, Weichhart T, Klavins K, Febbraio MA, Sharif O, Schabbauer G. The PI3K pathway preserves metabolic health through MARCO-dependent lipid uptake by adipose tissue macrophages. Nat Metab 2020; 2:1427-1442. [PMID: 33199895 DOI: 10.1038/s42255-020-00311-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 10/09/2020] [Indexed: 12/25/2022]
Abstract
Adipose tissue macrophages (ATMs) display tremendous heterogeneity depending on signals in their local microenvironment and contribute to the pathogenesis of obesity. The phosphoinositide 3-kinase (PI3K) signalling pathway, antagonized by the phosphatase and tensin homologue (PTEN), is important for metabolic responses to obesity. We hypothesized that fluctuations in macrophage-intrinsic PI3K activity via PTEN could alter the trajectory of metabolic disease by driving distinct ATM populations. Using mice harbouring macrophage-specific PTEN deletion or bone marrow chimeras carrying additional PTEN copies, we demonstrate that sustained PI3K activity in macrophages preserves metabolic health in obesity by preventing lipotoxicity. Myeloid PI3K signalling promotes a beneficial ATM population characterized by lipid uptake, catabolism and high expression of the scavenger macrophage receptor with collagenous structure (MARCO). Dual MARCO and myeloid PTEN deficiencies prevent the generation of lipid-buffering ATMs, reversing the beneficial actions of elevated myeloid PI3K activity in metabolic disease. Thus, macrophage-intrinsic PI3K signalling boosts metabolic health by driving ATM programmes associated with MARCO-dependent lipid uptake.
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Affiliation(s)
- Julia S Brunner
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Andrea Vogel
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Alexander Lercher
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Michael Caldera
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
- Max Perutz Laboratories, Vienna, Austria
| | - Ana Korosec
- Skin and Endothelium Research Division, Department of Dermatology, Medical University of Vienna, Vienna, Austria
| | - Marlene Pühringer
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Melanie Hofmann
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Alexander Hajto
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Markus Kieler
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Lucia Quemada Garrido
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Martina Kerndl
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Mario Kuttke
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | | | - Maria W Górna
- Biological and Chemical Research Centre, Department of Chemistry, University of Warsaw, Warsaw, Poland
| | - Marta Kulik
- Biological and Chemical Research Centre, Department of Chemistry, University of Warsaw, Warsaw, Poland
| | - Paulina M Dominiak
- Biological and Chemical Research Centre, Department of Chemistry, University of Warsaw, Warsaw, Poland
| | - Amanda E Brandon
- Insulin Action and Energy Metabolism Laboratory, Division of Diabetes & Metabolism, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
- Faculty of Medicine and Health, School of Medical Sciences, University of Sydney, Sydney, New South Wales, Australia
| | - Emma Estevez
- Cellular & Molecular Metabolism Laboratory, Division of Diabetes & Metabolism, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
| | - Casey L Egan
- Cellular & Molecular Metabolism Laboratory, Division of Diabetes & Metabolism, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Florian Gruber
- Research Division of Biology and Pathobiology of the Skin, Department of Dermatology, Medical University of Vienna, Vienna, Austria
| | - Martina Schweiger
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Jörg Menche
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
- Max Perutz Laboratories, Vienna, Austria
| | - Andreas Bergthaler
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Thomas Weichhart
- Center of Pathobiochemistry and Genetics, Institute of Medical Genetics, Medical University of Vienna, Vienna, Austria
| | - Kristaps Klavins
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
- Rudolfs Cimdins Riga Biomaterials Innovations and Development Centre, Riga Technical University, Riga, Latvia
| | - Mark A Febbraio
- Cellular & Molecular Metabolism Laboratory, Division of Diabetes & Metabolism, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Omar Sharif
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria.
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria.
| | - Gernot Schabbauer
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria.
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria.
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15
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Vidhya R, Anuradha CV. Anti-inflammatory effects of troxerutin are mediated through elastase inhibition. Immunopharmacol Immunotoxicol 2020; 42:423-435. [PMID: 32762381 DOI: 10.1080/08923973.2020.1806870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
CONTEXT Obesity is a chronic low-grade inflammatory state associated with immune cell infiltration into the adipose tissue (AT). We hypothesize that the anti-obesity and anti-inflammatory effects of troxerutin (TX) are mediated through inhibition of elastase. OBJECTIVE To determine the inhibitory effect of TX on elastase in vitro and in tumor necrosis factor alpha (TNFα) induced 3T3-L1 adipocytes and the molecular interaction of TX with human neutrophil elastase (HNE). MATERIALS AND METHODS Differentiated 3T3-L1 adipocytes were pretreated with TX, elastatinal (ELAS) or sodium salicylate (SAL) before exposure to TNFα. Lipid accumulation, reactive oxygen species (ROS) generation and oxidant-antioxidant balance were examined. The mRNA and protein expression of TNFα, interleukin-6, monocyte chemoattractant protein-1, adiponectin, leptin, resistin, chemerin, and elastase were analyzed. Elastase inhibition by TX and ELAS in a cell free system and docking studies for HNE with TX and ELAS were performed. RESULTS TX, ELAS or SAL pretreatment had lowered lipid droplets formation and TG content. TX suppressed ROS generation, oxidative stress and improved antioxidant status. The expression of inflammatory cytokines and elastase was downregulated while that of adiponectin was upregulated by TX. The concentration required to produce 50% inhibition in vitro (IC50) was 11.5 μM for TX and 16.9 μM for ELAS. TX showed hydrogen bonding and hydrophobic interactions with elastase. DISCUSSION TNFα induces inflammation of 3T3-L1 cells through elastase activation. TX inhibits elastase activity, downregulates expression and binds with elastase. CONCLUSION The antioxidant and anti-inflammatory activities of TX in AT could be of relevance in the management of obesity.
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Affiliation(s)
- Ramachandran Vidhya
- Department of Biochemistry and Biotechnology, Annamalai University, Annamalai Nagar, Tamil Nadu, India
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16
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Kumar AA, Satheesh G, Vijayakumar G, Chandran M, Prabhu PR, Simon L, Kutty VR, Kartha CC, Jaleel A. Plasma leptin level mirrors metabolome alterations in young adults. Metabolomics 2020; 16:87. [PMID: 32772182 DOI: 10.1007/s11306-020-01708-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 08/03/2020] [Indexed: 12/29/2022]
Abstract
INTRODUCTION Leptin is known to regulate pathways of energy metabolism, reproduction, and control appetite. Whether plasma leptin levels reflect changes in metabolites of these pathways is unknown. OBJECTIVES We aimed to find whether there is an association between leptin levels and levels of metabolites of energy and hormone metabolism. METHODS We performed an untargeted metabolomics analysis of plasma from 110 healthy adults (men: women = 1:1; aged 18-40 years), using liquid chromatography-tandem mass spectrometry. Blood samples were collected from all the study subjects in the fasting state. Clinical features and markers of obesity and Type 2 diabetes mellitus (T2DM) were assessed in all. The association between levels of metabolites and clinical and biochemical parameters was identified using the multivariable-adjusted linear regression model and PLS-DA analysis. RESULTS The leptin level was found to have a significant association with a substantial number of metabolites in women and men. Leptin level was positively associated with glycocholic acid and arachidic acid, metabolites related to energy metabolisms, pregnanediol-3-glucuronide, a metabolite of progesterone metabolism, and quercetin 3'-sulfate, a diet-derived metabolite. Leptin level was negatively associated with ponasteroside A and barringtogenol C levels. Leptin level was positively correlated with adiponectin and negatively with total calorie intake and levels of triglyceride and very-low-density lipoprotein. Leptin levels were associated with lipid and sex hormone metabolism in women, while metabolites involved in amino acid metabolism were correlated to leptin in men. CONCLUSION Our study indicates that leptin level reflects metabolome alterations and hence could be a useful marker to detect early changes in energy and hormone metabolisms.
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Affiliation(s)
- A Aneesh Kumar
- Cardiovascular Diseases & Diabetes Biology, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, Kerala, 695012, India
- Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India
| | - Gopika Satheesh
- Cardiovascular Diseases & Diabetes Biology, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, Kerala, 695012, India
| | - Gadadharan Vijayakumar
- Medical Trust Hospital and Diabetes Care Centre, Kulanada, Pathanamthitta, Kerala, India
| | - Mahesh Chandran
- Mass Spectrometry and Proteomics Core Facility, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, Kerala, 695012, India
| | - Priya R Prabhu
- Cancer Research Program, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, Kerala, 695012, India
| | - Leena Simon
- Medical Trust Hospital and Diabetes Care Centre, Kulanada, Pathanamthitta, Kerala, India
| | - Vellappillil Raman Kutty
- Achutha Menon Centre for Health Science Studies, Sree Chitra Tirunal Institute for Medical Sciences & Technology, Thiruvananthapuram, Kerala, 695012, India
| | - Chandrasekharan C Kartha
- Society for Continuing Medical Education & Research, Kerala Institute of Medical Sciences, Thiruvananthapuram, Kerala, 695029, India
| | - Abdul Jaleel
- Cardiovascular Diseases & Diabetes Biology, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, Kerala, 695012, India.
- Mass Spectrometry and Proteomics Core Facility, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, Kerala, 695012, India.
- Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India.
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17
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Dahik VD, Frisdal E, Le Goff W. Rewiring of Lipid Metabolism in Adipose Tissue Macrophages in Obesity: Impact on Insulin Resistance and Type 2 Diabetes. Int J Mol Sci 2020; 21:ijms21155505. [PMID: 32752107 PMCID: PMC7432680 DOI: 10.3390/ijms21155505] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 07/28/2020] [Accepted: 07/30/2020] [Indexed: 12/12/2022] Open
Abstract
Obesity and its two major comorbidities, insulin resistance and type 2 diabetes, represent worldwide health issues whose incidence is predicted to steadily rise in the coming years. Obesity is characterized by an accumulation of fat in metabolic tissues resulting in chronic inflammation. It is now largely accepted that adipose tissue inflammation underlies the etiology of these disorders. Adipose tissue macrophages (ATMs) represent the most enriched immune fraction in hypertrophic, chronically inflamed adipose tissue, and these cells play a key role in diet-induced type 2 diabetes and insulin resistance. ATMs are triggered by the continuous influx of dietary lipids, among other stimuli; however, how these lipids metabolically activate ATM depends on their nature, composition and localization. This review will discuss the fate and molecular programs elicited within obese ATMs by both exogenous and endogenous lipids, as they mediate the inflammatory response and promote or hamper the development of obesity-associated insulin resistance and type 2 diabetes.
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Role of the Nox4/AMPK/mTOR signaling axe in adipose inflammation-induced kidney injury. Clin Sci (Lond) 2020; 134:403-417. [PMID: 32095833 DOI: 10.1042/cs20190584] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 02/03/2020] [Accepted: 02/10/2020] [Indexed: 12/25/2022]
Abstract
Diabetic kidney disease is one of the most serious complications of diabetes worldwide and is the leading cause of end-stage renal disease. While research has primarily focused on hyperglycemia as a key player in the pathophysiology of diabetic complications, recently, increasing evidence have underlined the role of adipose inflammation in modulating the development and/or progression of diabetic kidney disease. This review focuses on how adipose inflammation contribute to diabetic kidney disease. Furthermore, it discusses in detail the underlying mechanisms of adipose inflammation, including pro-inflammatory cytokines, oxidative stress, and AMPK/mTOR signaling pathway and critically describes their role in diabetic kidney disease. This in-depth understanding of adipose inflammation and its impact on diabetic kidney disease highlights the need for novel interventions in the treatment of diabetic complications.
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19
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Affiliation(s)
- Suzana D. Savkovic
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA, USA,
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20
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Amorim NRT, Souza-Almeida G, Luna-Gomes T, Bozza PT, Canetti C, Diaz BL, Maya-Monteiro CM, Bandeira-Melo C. Leptin Elicits In Vivo Eosinophil Migration and Activation: Key Role of Mast Cell-Derived PGD 2. Front Endocrinol (Lausanne) 2020; 11:572113. [PMID: 33117286 PMCID: PMC7551309 DOI: 10.3389/fendo.2020.572113] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 09/09/2020] [Indexed: 12/16/2022] Open
Abstract
Eosinophils are key regulators of adipose tissue homeostasis, thus characterization of adipose tissue-related molecular factors capable of regulating eosinophil activity is of great interest. Leptin is known to directly activate eosinophils in vitro, but leptin ability of inducing in vivo eosinophilic inflammatory response remains elusive. Here, we show that leptin elicits eosinophil influx as well as its activation, characterized by increased lipid body biogenesis and LTC4 synthesis. Such leptin-triggered eosinophilic inflammatory response was shown to be dependent on activation of the mTOR signaling pathway, since it was (i) inhibited by rapamycin pre-treatment and (ii) reduced in PI3K-deficient mice. Local infiltration of activated eosinophils within leptin-driven inflammatory site was preceded by increased levels of classical mast cell-derived molecules, including TNFα, CCL5 (RANTES), and PGD2. Thus, mice were pre-treated with a mast cell degranulating agent compound 48/80 which was capable to impair leptin-induced PGD2 release, as well as eosinophil recruitment and activation. In agreement with an indirect mast cell-driven phenomenon, eosinophil accumulation induced by leptin was abolished in TNFR-1 deficient and also in HQL-79-pretreated mice, but not in mice pretreated with neutralizing antibodies against CCL5, indicating that both typical mast cell-driven signals TNFα and PGD2, but not CCL5, contribute to leptin-induced eosinophil influx. Distinctly, leptin-induced eosinophil lipid body (lipid droplet) assembly and LTC4 synthesis appears to depend on both PGD2 and CCL5, since both HQL-79 and anti-CCL5 treatments were able to inhibit these eosinophil activation markers. Altogether, our data show that leptin triggers eosinophilic inflammation in vivo via an indirect mechanism dependent on activation of resident mast cell secretory activity and mediation by TNFα, CCL5, and specially PGD2.
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Affiliation(s)
- Natália R. T. Amorim
- Laboratório de Inflamação, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Glaucia Souza-Almeida
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz - IOC, FIOCRUZ, Rio de Janeiro, Brazil
- Laboratório de Imunoinflamação, Instituto de Biologia, Universidade de Campinas, Campinas, Brazil
| | - Tatiana Luna-Gomes
- Laboratório de Inflamação, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- Departamento de Ciências da Natureza, Instituto de Aplicação Fernando Rodrigues da Silveira, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Patricia T. Bozza
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz - IOC, FIOCRUZ, Rio de Janeiro, Brazil
| | - Claudio Canetti
- Laboratório de Inflamação, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Bruno L. Diaz
- Laboratório de Inflamação, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Clarissa M. Maya-Monteiro
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz - IOC, FIOCRUZ, Rio de Janeiro, Brazil
- *Correspondence: Christianne Bandeira-Melo, ; Clarissa M. Maya-Monteiro,
| | - Christianne Bandeira-Melo
- Laboratório de Inflamação, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- *Correspondence: Christianne Bandeira-Melo, ; Clarissa M. Maya-Monteiro,
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21
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Duque TL, Siqueira MS, Travassos LH, Moreira OC, Bozza PT, Melo RC, Henriques-Pons A, Menna-Barreto RF. The induction of host cell autophagy triggers defense mechanisms against Trypanosoma cruzi infection in vitro. Eur J Cell Biol 2020; 99:151060. [DOI: 10.1016/j.ejcb.2019.151060] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 11/06/2019] [Accepted: 11/19/2019] [Indexed: 01/21/2023] Open
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22
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Goldstein N, Haim Y, Mattar P, Hadadi-Bechor S, Maixner N, Kovacs P, Blüher M, Rudich A. Leptin stimulates autophagy/lysosome-related degradation of long-lived proteins in adipocytes. Adipocyte 2019; 8:51-60. [PMID: 30676227 PMCID: PMC6768270 DOI: 10.1080/21623945.2019.1569447] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Obesity, a condition most commonly associated with hyper-leptinemia, is also characterized by increased expression of autophagy genes and likely autophagic activity in human adipose tissue (AT). Indeed, circulating leptin levels were previously shown to positively associate with the expression levels of autophagy genes such as Autophagy related gene-5 (ATG5). Here we hypothesized that leptin acts in an autocrine-paracrine manner to increase autophagy in two major AT cell populations, adipocytes and macrophages. We followed the dynamics of autophagosomes following acute leptin administration with or without a leptin receptor antagonist (SMLA) using high-throughput live-cell imaging in murine epididymal adipocyte and macrophage (RAW264.7) cell-lines. In macrophages leptin exerted only a mild effect on autophagy dynamics, tending to attenuate autophagosomes growth rate. In contrast, leptin-treated adipocytes exhibited a moderate, ~20% increase in the rate of autophagosome growth, an effect that was blocked by SMLA. This finding corresponded to mild increases in mRNA and protein expression of key autophagy genes. Interestingly, a long-lived proteins degradation assay uncovered a robust, >2-fold leptin-mediated stimulation of the autophagy/lysosome-related (bafilomycin-inhibited) activity, which was entirely blocked by SMLA. Collectively, leptin regulates autophagy in a cell-type specific manner. In adipocytes, autophagosome dynamics is moderately enhanced, but even more pronounced stimulation is seen in autophagy-related long-lived protein degradation. These findings suggest a causal link between obesity-associated hyperleptinemia and elevated adipocyte and AT autophagy-related processes.
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Affiliation(s)
- Nir Goldstein
- Department of Clinical Biochemistry and Pharmacology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Yulia Haim
- Department of Clinical Biochemistry and Pharmacology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
- The National Institute of Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Pamela Mattar
- Department of Clinical Biochemistry and Pharmacology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Sapir Hadadi-Bechor
- Department of Clinical Biochemistry and Pharmacology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
- The National Institute of Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Nitzan Maixner
- Department of Clinical Biochemistry and Pharmacology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Peter Kovacs
- Department of Medicine, University of Leipzig, Leipzig, Germany
| | - Matthias Blüher
- Department of Medicine, University of Leipzig, Leipzig, Germany
| | - Assaf Rudich
- Department of Clinical Biochemistry and Pharmacology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
- The National Institute of Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
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23
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Crotalus durissus ruruima Snake Venom and a Phospholipase A 2 Isolated from This Venom Elicit Macrophages to Form Lipid Droplets and Synthesize Inflammatory Lipid Mediators. J Immunol Res 2019; 2019:2745286. [PMID: 31781674 PMCID: PMC6875421 DOI: 10.1155/2019/2745286] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 05/13/2019] [Accepted: 09/03/2019] [Indexed: 12/15/2022] Open
Abstract
Viper snake Crotalus durissus ruruima (Cdr) is a subspecies found in northern area of Brazil. Among the snakes of Crotalus genus subspecies, the venom of Cdr presents highest level of crotoxin, which is the major component of Crotalus snake venoms, formed by two subunits (crotapotin and a phospholipase A2 named CBr) and presents potent neurotoxic activity. Curiously, the venom of C. d. ruruima (CdrV) is better neutralized by antibothropic than by anticrotalic serum, strongly suggesting that this venom has similarities with venom of Bothrops genus snakes with regard to the ability to induce inflammation. Macrophages are cells with a central role in inflammatory and immunological responses. Upon inflammatory stimuli, these cells exhibit increased numbers of lipid droplets, which are key organelles in the synthesis and release of inflammatory mediators. However, the effects of CdrV and CBr in macrophage functions are unknown. We herein investigated the ability of CdrV and CBr to activate macrophages with focus on the formation of lipid droplets (LDs), synthesis of lipid mediators, and mechanisms involved in these effects. The involvement of LDs in PGE2 biosynthesis was also assessed. Stimulation of murine macrophages with CdrV and CBr induced an increased number of LDs and release of prostanoids (PGE2, PGD2, and TXB2). Neither CdrV nor CBr induced the expression of COX-1 and COX-2 by macrophages. LDs induced by both CdrV and CBr are associated to PLIN2 recruitment and expression and were shown to be dependent on COX-1, but not COX-2 activity. Moreover, PGE2 colocalized to CdrV- and CBr-induced LDs, revealing the role of these organelles as sites for the synthesis of prostanoids. These results evidence, for the first time, the ability of a whole snake venom to induce formation of LDs and the potential role of these organelles for the production of inflammatory mediators during envenomation by Crotalus snakes.
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Balboa MA, de Pablo N, Meana C, Balsinde J. The role of lipins in innate immunity and inflammation. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1864:1328-1337. [DOI: 10.1016/j.bbalip.2019.06.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 05/07/2019] [Accepted: 06/01/2019] [Indexed: 02/08/2023]
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25
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Ghadge AA, Khaire AA. Leptin as a predictive marker for metabolic syndrome. Cytokine 2019; 121:154735. [DOI: 10.1016/j.cyto.2019.154735] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 03/16/2019] [Accepted: 05/24/2019] [Indexed: 02/07/2023]
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Abstract
In the present study, we identify and describe an important cross-talk between leptin signaling and macrophage functions in the context of Salmonella Typhimurium infection. Genetic ablation of leptin receptor or pharmacological antagonization of leptin augmented lysosomal functions in macrophages, reduced S. Typhimurium burden, and diminished inflammation both in vitro and in vivo. Leptin signaling activates mTORC2/Akt pathway through the down-regulation of Phlpp1 phosphatase, thus impairs lysosome-mediated pathogen clearance. The dynamic interplay between metabolism and immune responses in health and disease, by which different immune cells impact on metabolic processes, are being increasingly appreciated. However, the potential of master regulators of metabolism to control innate immunity are less understood. Here, we studied the cross-talk between leptin signaling and macrophage function in the context of bacterial infections. We found that upon infection with Gram-negative pathogens, such as Salmonella Typhimurium, leptin receptor (Lepr) expression increased in both mouse and human macrophages. Unexpectedly, both genetic Lepr ablation in macrophages and global pharmacologic leptin antagonization augmented lysosomal functions, reduced S. Typhimurium burden, and diminished inflammation in vitro and in vivo. Mechanistically, we show that leptin induction activates the mTORC2/Akt pathway and subsequently down-regulates Phlpp1 phosphatase, allowing for phosphorylated Akt to impair lysosomal-mediated pathogen clearance. These data highlight a link between leptin signaling, the mTORC2/Phlpp1/Akt axis, and lysosomal activity in macrophages and have important therapeutic implications for modulating innate immunity to combat Gram-negative bacterial infections.
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27
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Keuper M. On the role of macrophages in the control of adipocyte energy metabolism. Endocr Connect 2019; 8:R105-R121. [PMID: 31085768 PMCID: PMC6590200 DOI: 10.1530/ec-19-0016] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 05/14/2019] [Indexed: 12/11/2022]
Abstract
The crosstalk between macrophages (MΦ) and adipocytes within white adipose tissue (WAT) influences obesity-associated insulin resistance and other associated metabolic disorders, such as atherosclerosis, hypertension and type 2 diabetes. MΦ infiltration is increased in WAT during obesity, which is linked to decreased mitochondrial content and activity. The mechanistic interplay between MΦ and mitochondrial function of adipocytes is under intense investigation, as MΦ and inflammatory pathways exhibit a pivotal role in the reprogramming of WAT metabolism in physiological responses during cold, fasting and exercise. Thus, the underlying immunometabolic pathways may offer therapeutic targets to correct obesity and metabolic disease. Here, I review the current knowledge on the quantity and the quality of human adipose tissue macrophages (ATMΦ) and their impact on the bioenergetics of human adipocytes. The effects of ATMΦ and their secreted factors on mitochondrial function of white adipocytes are discussed, including recent research on MΦ as part of an immune signaling cascade involved in the 'browning' of WAT, which is defined as the conversion from white, energy-storing adipocytes into brown, energy-dissipating adipocytes.
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Affiliation(s)
- Michaela Keuper
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
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28
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Monteiro L, Pereira JADS, Palhinha L, Moraes‐Vieira PMM. Leptin in the regulation of the immunometabolism of adipose tissue‐macrophages. J Leukoc Biol 2019; 106:703-716. [DOI: 10.1002/jlb.mr1218-478r] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 03/19/2019] [Accepted: 04/26/2019] [Indexed: 12/13/2022] Open
Affiliation(s)
- Lauar Monteiro
- Laboratory of ImmunometabolismDepartment of Genetics, Evolution, Microbiology and ImmunologyInstitute of BiologyUniversity of Campinas Sao Paulo Brazil
| | - Jéssica Aparecida da Silva Pereira
- Laboratory of ImmunometabolismDepartment of Genetics, Evolution, Microbiology and ImmunologyInstitute of BiologyUniversity of Campinas Sao Paulo Brazil
- Department of ImmunologyInstitute of Biomedical SciencesUniversity of Sao Paulo Sao Paulo Brazil
| | - Lohanna Palhinha
- Laboratory of ImmunopharmacologyOswaldo Cruz InstituteOswaldo Cruz Foundation (FIOCRUZ) Rio de Janeiro Rio de Janeiro Brazil
| | - Pedro Manoel M. Moraes‐Vieira
- Laboratory of ImmunometabolismDepartment of Genetics, Evolution, Microbiology and ImmunologyInstitute of BiologyUniversity of Campinas Sao Paulo Brazil
- Department of ImmunologyInstitute of Biomedical SciencesUniversity of Sao Paulo Sao Paulo Brazil
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29
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Silva AR, Gonçalves-de-Albuquerque CF, Pérez AR, Carvalho VDF. Immune-endocrine interactions related to a high risk of infections in chronic metabolic diseases: The role of PPAR gamma. Eur J Pharmacol 2019; 854:272-281. [PMID: 30974105 DOI: 10.1016/j.ejphar.2019.04.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 03/11/2019] [Accepted: 04/02/2019] [Indexed: 02/06/2023]
Abstract
Diverse disturbances in immune-endocrine circuitries are involved in the development and aggravation of several chronic metabolic diseases (CMDs), including obesity, diabetes, and metabolic syndrome. The chronic inflammatory syndrome observed in CMDs culminates in dysregulated immune responses with low microbial killing efficiency, by means low host innate immune response, and loss of ability to eliminate the pathogens, which results in a high prevalence of infectious diseases, including pneumonia, tuberculosis, and sepsis. Herein, we review evidence pointing out PPARγ as a putative player in immune-endocrine disturbances related to increased risk of infections in CMDs. Cumulated evidence indicates that PPARγ activation modulates host cells to control inflammation during CMDs because of PPARγ agonists have anti-inflammatory and pro-resolutive properties, increasing host ability to eliminate pathogen, modulating hormone production, and restoring glucose and lipid homeostasis. As such, we propose PPARγ as a putative therapeutic adjuvant for patients with CMDs to favor a better infection control.
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Affiliation(s)
- Adriana Ribeiro Silva
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (FIOCRUZ), Avenida Brasil, 4365, Rio de Janeiro, RJ, Brazil.
| | - Cassiano Felippe Gonçalves-de-Albuquerque
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (FIOCRUZ), Avenida Brasil, 4365, Rio de Janeiro, RJ, Brazil; Laboratório de Imunofarmacologia, Instituto Biomédico, Universidade Federal do Estado do Rio de Janeiro, Unirio, Brazil.
| | - Ana Rosa Pérez
- Instituto de Inmunología Clínica y Experimental de Rosario (IDICER-CONICET UNR), 2000, Rosario, Argentina.
| | - Vinicius de Frias Carvalho
- Laboratório de Inflamação, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (FIOCRUZ), Avenida Brasil, 4365, Rio de Janeiro, RJ, Brazil.
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Palhinha L, Liechocki S, Hottz ED, Pereira JADS, de Almeida CJ, Moraes-Vieira PMM, Bozza PT, Maya-Monteiro CM. Leptin Induces Proadipogenic and Proinflammatory Signaling in Adipocytes. Front Endocrinol (Lausanne) 2019; 10:841. [PMID: 31920961 PMCID: PMC6923660 DOI: 10.3389/fendo.2019.00841] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 11/19/2019] [Indexed: 12/12/2022] Open
Abstract
Background: Leptin is an adipokine with well-known effects on the central nervous system including the induction of energy expenditure and satiety. Leptin also has major relevance when activating immune cells and modulating inflammatory response. In obesity, increases in white adipose tissue accumulation and leptin levels are accompanied by hypothalamic resistance to leptin. Even though the adipose tissue is a leptin-rich environment, the local actions of leptin regarding adipogenesis were not thoroughly investigated until now. Here we evaluate the contributions of leptins direct signaling in preadipocytes and adipose tissue-derived stromal cells (ASCs) for adipogenesis. Methods: Adipocytes were differentiated from the murine lineage of preadipocytes 3T3-L1 or ASCs from subcutaneous and visceral (retroperitoneal) fat depots from C57Bl/6J mice. Differentiating cells were treated with leptin in addition to or in replacement of insulin. The advance of adipogenesis was assessed by the expression and secretion of adipogenesis- and lipogenesis-related proteins by Western blot and immunoenzimatic assays, and the accumulation of lipid droplets by fluorescence microscopy. Results: Leptin treatment in 3T3-L1 preadipocytes or ASCs increased the production of the adipogenesis- and lipogenesis-related proteins PLIN1, CAV-1, PPARγ, SREBP1C, and/or adiponectin at earlier stages of differentiation. In 3T3-L1 preadipocytes, we found that leptin induced lipid droplets' formation in an mTOR-dependent manner. Also, leptin induced a proinflammatory cytokine profile in 3T3-L1 and ASCs, modulating the production of TNF-α, IL-10, and IL-6. Since insulin is considered an essential factor for preadipocyte differentiation, we asked whether leptin would support adipogenesis in the absence of insulin. Importantly, leptin induced the formation of lipid droplets and the expression of adipogenesis-related proteins independently of insulin during the differentiation of 3T3-L1 cells and ASCs. Conclusions: Our results demonstrate that leptin induces intracellular signaling in preadipocytes and adipocytes promoting adipogenesis and modulating the secretion of inflammatory mediators. Also, leptin restores adipogenesis in the absence of insulin. These findings contribute to the understanding of the local signaling of leptin in precursor and mature adipose cells. The proadipogenic role of leptin unraveled here may be of especial relevance during obesity, when its central signaling is defective.
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Affiliation(s)
- Lohanna Palhinha
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute (IOC), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Sally Liechocki
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute (IOC), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Eugenio D. Hottz
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute (IOC), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
- Laboratory of Glycoconjugates Analysis, Department of Biochemistry, Federal University of Juiz de Fora (UFJF), Juiz de Fora, Brazil
| | - Jéssica Aparecida da Silva Pereira
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, University of Campinas, Campinas, Brazil
- Post-Graduate Program in Immunology, Institute of Biological Sciences, University of Sao Paulo, São Paulo, Brazil
| | - Cecília J. de Almeida
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute (IOC), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Pedro Manoel M. Moraes-Vieira
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, University of Campinas, Campinas, Brazil
- Post-Graduate Program in Immunology, Institute of Biological Sciences, University of Sao Paulo, São Paulo, Brazil
- Experimental Medicine Research Cluster, EMRC, University of Cammpinas, Campinas, Brazil
| | - Patrícia T. Bozza
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute (IOC), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Clarissa Menezes Maya-Monteiro
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute (IOC), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
- *Correspondence: Clarissa Menezes Maya-Monteiro ;
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Seddon JA, Chiang SS, Esmail H, Coussens AK. The Wonder Years: What Can Primary School Children Teach Us About Immunity to Mycobacterium tuberculosis? Front Immunol 2018; 9:2946. [PMID: 30619306 PMCID: PMC6300506 DOI: 10.3389/fimmu.2018.02946] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 11/30/2018] [Indexed: 12/22/2022] Open
Abstract
In high burden settings, the risk of infection with Mycobacterium tuberculosis increases throughout childhood due to cumulative exposure. However, the risk of progressing from tuberculosis (TB) infection to disease varies by age. Young children (<5 years) have high risk of disease progression following infection. The risk falls in primary school children (5 to <10 years), but rises again during puberty. TB disease phenotype also varies by age: generally, young children have intrathoracic lymph node disease or disseminated disease, while adolescents (10 to <20 years) have adult-type pulmonary disease. TB risk also exhibits a gender difference: compared to adolescent boys, adolescent girls have an earlier rise in disease progression risk and higher TB incidence until early adulthood. Understanding why primary school children, during what we term the "Wonder Years," have low TB risk has implications for vaccine development, therapeutic interventions, and diagnostics. To understand why this group is at low risk, we need a better comprehension of why younger children and adolescents have higher risks, and why risk varies by gender. Immunological response to M. tuberculosis is central to these issues. Host response at key stages in the immunopathological interaction with M. tuberculosis influences risk and disease phenotype. Cell numbers and function change dramatically with age and sexual maturation. Young children have poorly functioning innate cells and a Th2 skew. During the "Wonder Years," there is a lymphocyte predominance and a Th1 skew. During puberty, neutrophils become more central to host response, and CD4+ T cells increase in number. Sex hormones (dehydroepiandrosterone, adiponectin, leptin, oestradiol, progesterone, and testosterone) profoundly affect immunity. Compared to girls, boys have a stronger Th1 profile and increased numbers of CD8+ T cells and NK cells. Girls are more Th2-skewed and elicit more enhanced inflammatory responses. Non-immunological factors (including exposure intensity, behavior, and co-infections) may impact disease. However, given the consistent patterns seen across time and geography, these factors likely are less central. Strategies to protect children and adolescents from TB may need to differ by age and sex. Further work is required to better understand the contribution of age and sex to M. tuberculosis immunity.
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Affiliation(s)
- James A. Seddon
- Department of Paediatrics, Imperial College London, London, United Kingdom
- Desmond Tutu TB Centre, Department of Paediatrics and Child Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Silvia S. Chiang
- Department of Pediatrics, Warren Alpert Medical School of Brown University, Providence, RI, United States
- Center for International Health Research, Rhode Island Hospital, Providence, RI, United States
| | - Hanif Esmail
- Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Anna K. Coussens
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
- Infection and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Division of Medical Biology, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia
- Division of Medical Microbiology, Department of Pathology, University of Cape Town, Cape Town, South Africa
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Amorim NRT, Luna-Gomes T, Gama-Almeida M, Souza-Almeida G, Canetti C, Diaz BL, Weller PF, Torres Bozza P, Maya-Monteiro CM, Bandeira-Melo C. Leptin Elicits LTC 4 Synthesis by Eosinophils Mediated by Sequential Two-Step Autocrine Activation of CCR3 and PGD 2 Receptors. Front Immunol 2018; 9:2139. [PMID: 30298073 PMCID: PMC6160734 DOI: 10.3389/fimmu.2018.02139] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Accepted: 08/30/2018] [Indexed: 12/11/2022] Open
Abstract
Leptin is a cytokine, produced mainly by mature adipocytes, that regulates the central nervous system, mainly to suppress appetite and stimulate energy expenditure. Leptin also regulates the immune response by controlling activation of immunomodulatory cells, including eosinophils. While emerging as immune regulatory cells with roles in adipose tissue homeostasis, eosinophils have a well-established ability to synthesize pro-inflammatory molecules such as lipid mediators, a key event in several inflammatory pathologies. Here, we investigated the impact and mechanisms involved in leptin-driven activation of eicosanoid-synthesizing machinery within eosinophils. Direct in vitro activation of human or mouse eosinophils with leptin elicited synthesis of lipoxygenase as well as cyclooxygenase products. Displaying selectivity, leptin triggered synthesis of LTC4 and PGD2, but not PGE2, in parallel to dose-dependent induction of lipid body/lipid droplets biogenesis. While dependent on PI3K activation, leptin-driven eosinophil activation was also sensitive to pertussis toxin, indicating the involvement of G-protein coupled receptors on leptin effects. Leptin-induced lipid body-driven LTC4 synthesis appeared to be mediated through autocrine activation of G-coupled CCR3 receptors by eosinophil-derived CCL5, inasmuch as leptin was able to trigger rapid CCL5 secretion, and neutralizing anti-RANTES or anti-CCR3 antibodies blocked lipid body assembly and LTC4 synthesis induced by leptin. Remarkably, autocrine activation of PGD2 G-coupled receptors DP1 and DP2 also contributes to leptin-elicited lipid body-driven LTC4 synthesis by eosinophils in a PGD2-dependent fashion. Blockade of leptin-induced PGD2 autocrine/paracrine activity by a specific synthesis inhibitor or DP1 and DP2 receptor antagonists, inhibited both lipid body biogenesis and LTC4 synthesis induced by leptin stimulation within eosinophils. In addition, CCL5-driven CCR3 activation appears to precede PGD2 receptor activation within eosinophils, since neutralizing anti-CCL5 or anti-CCR3 antibodies inhibited leptin-induced PGD2 secretion, while it failed to alter PGD2-induced LTC4 synthesis. Altogether, sequential activation of CCR3 and then PGD2 receptors by autocrine ligands in response to leptin stimulation of eosinophils culminates with eosinophil activation, characterized here by assembly of lipidic cytoplasmic platforms synthesis and secretion of the pleiotropic lipid mediators, PGD2, and LTC4.
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Affiliation(s)
- Natália R T Amorim
- Laboratório de Inflamação, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Tatiana Luna-Gomes
- Laboratório de Inflamação, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.,Departamento de Ciências da Natureza, Instituto de Aplicação Fernando Rodrigues da Silveira, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marcos Gama-Almeida
- Laboratório de Inflamação, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Glaucia Souza-Almeida
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz-IOC, FIOCRUZ, Rio de Janeiro, Brazil
| | - Claudio Canetti
- Laboratório de Inflamação, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Bruno L Diaz
- Laboratório de Inflamação, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Peter F Weller
- Department of Medicine, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, MA, United States
| | - Patricia Torres Bozza
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz-IOC, FIOCRUZ, Rio de Janeiro, Brazil
| | | | - Christianne Bandeira-Melo
- Laboratório de Inflamação, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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Ratter JM, Tack CJ, Netea MG, Stienstra R. Environmental Signals Influencing Myeloid Cell Metabolism and Function in Diabetes. Trends Endocrinol Metab 2018; 29:468-480. [PMID: 29789206 DOI: 10.1016/j.tem.2018.04.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 04/18/2018] [Accepted: 04/19/2018] [Indexed: 12/13/2022]
Abstract
The environment induces metabolic reprogramming of immune cells via specific signaling pathways. Recent studies have revealed that changes in cell metabolism affect key immune cell functions including cytokine production and migration. In diabetes, these functions are either insufficiently or excessively activated, translating into diabetes-associated complications, including increased susceptibility to infection and accelerated cardiovascular disease. Diabetes alters the abundance of environmental signals, including glucose, insulin, and lipids. Subsequently, changes in environmental signals drive metabolic reprogramming, impair immune cell function, and ultimately contribute to diabetes-associated complications. We review here recent studies on changes in innate immune cell metabolism, especially in myeloid cells, that are driven by environmental signals relevant to diabetes, and discuss therapeutic perspectives of targeting metabolism of immune cells in diabetes.
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Affiliation(s)
- Jacqueline M Ratter
- Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands; Nutrition, Metabolism and Genomics Group, Division of Human Nutrition and Health, Wageningen University, Wageningen, The Netherlands
| | - Cees J Tack
- Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Mihai G Netea
- Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands; Department for Genomics and Immunoregulation, Life and Medical Sciences Institute (LIMES), University of Bonn, Bonn, Germany
| | - Rinke Stienstra
- Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands; Nutrition, Metabolism and Genomics Group, Division of Human Nutrition and Health, Wageningen University, Wageningen, The Netherlands.
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Zhang J, Jin J, Liu J, He Y, Zhang P, Ye W, Zhu W, Li M. A study of the correlation of insulin resistance and leptin with inflammatory factors and vascular endothelial injury in T2DM patients with CHD. Exp Ther Med 2018; 16:265-269. [PMID: 29896248 PMCID: PMC5995089 DOI: 10.3892/etm.2018.6170] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 04/17/2018] [Indexed: 12/18/2022] Open
Abstract
The purpose of this study was to explore the correlation of insulin resistance (IR) and leptin with inflammatory factors and vascular endothelial injury in patients with type 2 diabetes mellitus (T2DM) complicated with coronary heart disease (CHD) was explored. One hundred and fifty normal patients (normal group), 150 patients with pure T2DM (T2DM group) and 150 patients with T2DM complicated with coronary heart disease (T2DM + CHD group) were selected from Xi'an No. 5 Hospital. All the participants met our inclusion criteria. Age, body mass index, waist-to-hip ratio, blood lipid and fasting plasma glucose (FPG), of all the subjects were measured. Chemiluminescent immunoassay was adopted for the detection of FPG and double-antibody sandwich method was used for the determination of fasting plasma leptin, and assay of high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). Insulin resistance index (IRI) was used to evaluate IR and enzyme-linked immunosorbent assay was adopted for the detection of von Willebrand factor (vWF) and endothelin (ET-1). Compared with the control group, patients in the T2DM + CHD group and those in the T2DM group had higher homeostasis model assessment-IR, and higher assay of plasma leptin, hs-CRP, IL-6 and TNF-α (P<0.05), and lower vascular endothelial function (P<0.05). Moreover, compared with the T2DM group, T2DM + CHD group had higher plasma leptin, and higher assay of hs-CRP, IL-6 and TNF-α (P<0.05). IRI was positively correlated with hs-CRP (r=0.521, P=0.001), IL-6 (r=0.359, P=0.001) and TNF-α (r=0.386, P=0.001), leptin was positively correlated with hs-CRP (r=0.305, P=0.001), IL-6 (r=0.259, P=0.002) and TNF-α (r=0.429, P=0.001), and IRI had no correlation with ET-1 (r=0.058, P=0.734) and vWF (r=0.047, P=0.812), that is, it had no direct correlation with vascular endothelial function. Level of leptin was positively correlated with ET-1 (r=0.366, P=0.001) and vWF (r=0.471, P=0.001), that is, it was negatively correlated with vascular endothelial function. Our results showed that leptin, hs-CRP, IL-6 and TNF-α are involved in the occurrence and development of CHD in patients with T2DM. IR has no direct correlation with the occurrence and development of CHD in patients with T2DM.
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Affiliation(s)
- Jie Zhang
- Department of Cardiology, Xi'an No. 5 Hospital, Xi'an, Shaanxi 710082, P.R. China
| | - Jing Jin
- Department of Geriatrics, Xi'an No. 5 Hospital, Xi'an, Shaanxi 710082, P.R. China
| | - Jilun Liu
- Department of Cardiology, No. 215 Hospital of Shaanxi Nuclear Industry, Xianyang, Shaanxi 712000, P.R. China
| | - Yajun He
- Department of Cardiology, No. 215 Hospital of Shaanxi Nuclear Industry, Xianyang, Shaanxi 712000, P.R. China
| | - Peng Zhang
- Department of Cardiology, The Affiliated Hospital of Yan'an University, Yan'an, Shaanxi 716000, P.R. China
| | - Wucheng Ye
- Department of Cardiology, Xingyuan Hospital of Yulin, Yulin, Shaanxi 719000, P.R. China
| | - Wei Zhu
- Department of Clinical Laboratory, The Central Hospital of Baoji, Baoji, Shaanxi 721008, P.R. China
| | - Mingliang Li
- Department of Cardiovascular Medicine, Hanzhong People's Hospital, Hanzhong, Shaanxi 723000, P.R. China
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Al-Amodi HS, Abdelbasit NA, Fatani SH, Babakr AT, Mukhtar MM. The effect of obesity and components of metabolic syndrome on leptin levels in Saudi women. Diabetes Metab Syndr 2018; 12:357-364. [PMID: 29307577 DOI: 10.1016/j.dsx.2017.12.030] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 12/28/2017] [Indexed: 12/31/2022]
Abstract
BACKGROUND Leptin levels are reported to be increased with excessive body fat and is a potential determinant of obesity and its complications. Our Objective is to evaluate the relationship between leptin levels and BMI, waist circumference and metabolic syndrome components in normal and obese females classified according to their BMI. SUBJECTS AND METHODS A total of 136 female subjects aged between 20 and 60 years were recruited for the current study. Anthropometric measures included body mass index and waist circumference. The blood samples were used for estimation of plasma fasting blood glucose and serum was used for estimation of triglycerides, total cholesterol, low and high density lipoproteins, and total leptin. RESULTS Correlation between glucose and lipids profile with waist circumference among the whole study group (obese and non-obese) is reflecting that a strong positive correlation between BMI and blood glucose, serum TGs, cholesterol and LDL, a negative correlation was reported between BMI and serum HDL. Mean of leptin concentrations in two groups were found to be 5.77 ng/ml (±1.00) in non-obese and 28.89 ng/ml (±4.91) in the obese with metabolic syndrome. Leptin had a positive correlations with triglycerides (r = 0.84, p < 0.001), total cholesterol (r = 0.77, p < 0.001), LDL (r = 0.83, p < 0.001), waist circumference (r = 0.86, p < 0.001) and BMI (r = 0.72, p < 0.001) in the test group. a negative correlation was reported between BMI and serum HDL (r = -0.48, p < 0.001). CONCLUSION Leptin levels were high in Saudi women with high BMI and waist circumference. There was a significant correlation between leptin levels and Obesity.
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Affiliation(s)
- Hiba S Al-Amodi
- Department of Medical Biochemistry, Faculty of Medicine, Umm Al-Qura University, Makkah, Saudi Arabia.
| | - Nazik Altayeb Abdelbasit
- Department of Medical Biochemistry, Faculty of Medicine, Umm Al-Qura University, Makkah, Saudi Arabia.
| | - Samir H Fatani
- Department of Medical Biochemistry, Faculty of Medicine, Umm Al-Qura University, Makkah, Saudi Arabia.
| | - Abdullatif Taha Babakr
- Department of Medical Biochemistry, Faculty of Medicine, Umm Al-Qura University, Makkah, Saudi Arabia.
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Romero-Aguilar L, Montero-Lomeli M, Pardo JP, Guerra-Sánchez G. Lipid Index Determination by Liquid Fluorescence Recovery in the Fungal Pathogen Ustilago Maydis. J Vis Exp 2018. [PMID: 29683447 DOI: 10.3791/57279] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The article shows how to implement the LD index assay, which is a sensitive microplate assay to determine the accumulation of triacylglycerols (TAGs) in lipid droplets (LDs). LD index is obtained without lipid extraction. It allows measuring the LDs content in high-throughput experiments under different conditions such as growth in rich or nitrogen depleted media. Albeit the method was described for the first time to study the lipid droplet metabolism in Saccharomyces cerevisiae, it was successfully applied to the basidiomycete Ustilago maydis. Interestingly, and because LDs are organelles phylogenetically conserved in eukaryotic cells, the method can be applied to a large variety of cells, from yeast to mammalian cells. The LD index is based on the liquid fluorescence recovery assay (LFR) of the BODIPY 493/503 under quenching conditions, by the addition of cells fixed with formaldehyde. Potassium iodine is used as a fluorescence quencher. The ratio between the fluorescence and the optical density slopes is named LD index. Slopes are calculated from the straight lines obtained when BODIPY fluorescence and optical density at 600 nm (OD600) are plotted against sample addition. Optimal data quality is reflected by correlation coefficients equal or above 0.9 (r ≥ 0.9). Multiple samples can be read simultaneously as it can be implemented in a microplate. Since BODIPY 493/503 is a lipophilic fluorescent dye that partitions into the lipid droplets, it can be used in many types of cells that accumulate LDs.
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Affiliation(s)
- Lucero Romero-Aguilar
- Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional; Facultad de Medicina, Universidad Nacional Autónoma de México
| | - Mónica Montero-Lomeli
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro
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Boutens L, Hooiveld GJ, Dhingra S, Cramer RA, Netea MG, Stienstra R. Unique metabolic activation of adipose tissue macrophages in obesity promotes inflammatory responses. Diabetologia 2018; 61:942-953. [PMID: 29333574 PMCID: PMC6448980 DOI: 10.1007/s00125-017-4526-6] [Citation(s) in RCA: 136] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 11/13/2017] [Indexed: 12/23/2022]
Abstract
AIMS/HYPOTHESIS Recent studies have identified intracellular metabolism as a fundamental determinant of macrophage function. In obesity, proinflammatory macrophages accumulate in adipose tissue and trigger chronic low-grade inflammation, that promotes the development of systemic insulin resistance, yet changes in their intracellular energy metabolism are currently unknown. We therefore set out to study metabolic signatures of adipose tissue macrophages (ATMs) in lean and obese conditions. METHODS F4/80-positive ATMs were isolated from obese vs lean mice. High-fat feeding of wild-type mice and myeloid-specific Hif1α-/- mice was used to examine the role of hypoxia-inducible factor-1α (HIF-1α) in ATMs part of obese adipose tissue. In vitro, bone marrow-derived macrophages were co-cultured with adipose tissue explants to examine adipose tissue-induced changes in macrophage phenotypes. Transcriptome analysis, real-time flux measurements, ELISA and several other approaches were used to determine the metabolic signatures and inflammatory status of macrophages. In addition, various metabolic routes were inhibited to determine their relevance for cytokine production. RESULTS Transcriptome analysis and extracellular flux measurements of mouse ATMs revealed unique metabolic rewiring in obesity characterised by both increased glycolysis and oxidative phosphorylation. Similar metabolic activation of CD14+ cells in obese individuals was associated with diabetes outcome. These changes were not observed in peritoneal macrophages from obese vs lean mice and did not resemble metabolic rewiring in M1-primed macrophages. Instead, metabolic activation of macrophages was dose-dependently induced by a set of adipose tissue-derived factors that could not be reduced to leptin or lactate. Using metabolic inhibitors, we identified various metabolic routes, including fatty acid oxidation, glycolysis and glutaminolysis, that contributed to cytokine release by ATMs in lean adipose tissue. Glycolysis appeared to be the main contributor to the proinflammatory trait of macrophages in obese adipose tissue. HIF-1α, a key regulator of glycolysis, nonetheless appeared to play no critical role in proinflammatory activation of ATMs during early stages of obesity. CONCLUSIONS/INTERPRETATION Our results reveal unique metabolic activation of ATMs in obesity that promotes inflammatory cytokine release. Further understanding of metabolic programming in ATMs will most likely lead to novel therapeutic targets to curtail inflammatory responses in obesity. DATA AVAILABILITY Microarray data of ATMs isolated from obese or lean mice have been submitted to the Gene Expression Omnibus (accession no. GSE84000).
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Affiliation(s)
- Lily Boutens
- Nutrition, Metabolism and Genomics Group, Division of Human Nutrition, Wageningen University, Wageningen, the Netherlands
- Department of Internal Medicine, Radboud University Nijmegen Medical Centre, Geert Grooteplein Zuid 10, 6525 GA, Nijmegen, the Netherlands
| | - Guido J Hooiveld
- Nutrition, Metabolism and Genomics Group, Division of Human Nutrition, Wageningen University, Wageningen, the Netherlands
| | - Sourabh Dhingra
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
| | - Robert A Cramer
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
| | - Mihai G Netea
- Department of Internal Medicine, Radboud University Nijmegen Medical Centre, Geert Grooteplein Zuid 10, 6525 GA, Nijmegen, the Netherlands
| | - Rinke Stienstra
- Nutrition, Metabolism and Genomics Group, Division of Human Nutrition, Wageningen University, Wageningen, the Netherlands.
- Department of Internal Medicine, Radboud University Nijmegen Medical Centre, Geert Grooteplein Zuid 10, 6525 GA, Nijmegen, the Netherlands.
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Souza-Almeida G, D'Avila H, Almeida PE, Luna-Gomes T, Liechocki S, Walzog B, Hepper I, Castro-Faria-Neto HC, Bozza PT, Bandeira-Melo C, Maya-Monteiro CM. Leptin Mediates In Vivo Neutrophil Migration: Involvement of Tumor Necrosis Factor-Alpha and CXCL1. Front Immunol 2018; 9:111. [PMID: 29467755 PMCID: PMC5808117 DOI: 10.3389/fimmu.2018.00111] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 01/15/2018] [Indexed: 11/13/2022] Open
Abstract
Leptin directly activates macrophages and lymphocytes, but the role of leptin in neutrophil activation and migration is still controversial. Here, we investigate the in vivo mechanisms of neutrophil migration induced by leptin. The intraperitoneal injection of leptin (1 mg/kg) induces a time- and concentration-dependent neutrophil influx. We did not observe the enhancement of lipid bodies/droplets in neutrophils, after leptin treatment, as we had observed previously in peritoneal macrophages. The participation of leukotriene B4 (LTB4) in neutrophil recruitment triggered by leptin was investigated using different strategies. Leptin-induced neutrophil recruitment occurs both in the absence of 5-lipoxygenase activity in 5-lipoxygenase (5-LO)-/- mice and after the administration of either 5-LO inhibitor (Zileuton) or the LTB4 receptor antagonist (U-75302). Moreover, no direct induction of LTB4 by leptin could be observed. Neutrophil influx could not be prevented by the mammalian target of rapamycin (mTOR) inhibitor, rapamycin, contrasting with the leptin-induced signaling for lipid body formation in macrophage that is mTOR-dependent. Leptin administration led to tumor necrosis factor-alpha (TNFα) production by the peritoneal cells both in vivo and in vitro. In addition, neutrophil recruitment was inhibited in tumor necrosis factor receptor 1 (TNFR1-/-) mice, indicating a role for TNF in leptin-induced neutrophil recruitment to the peritoneal cavity. Leptin-induced neutrophil influx was PI3Kγ-dependent, as it was absent in PI3Kγ-/- mice. Accordingly, leptin induced the peritoneal cells to produce CXCL1, both in vivo and in vitro, and the neutrophil influx was ablated after using an antibody against CXCL1. Our results establish TNFα/TNFR1- and CXCL1-dependent signaling as important pathways for leptin-induced neutrophil migration in vivo.
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Affiliation(s)
- Glaucia Souza-Almeida
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Heloisa D'Avila
- Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil
| | - Patricia E Almeida
- Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil
| | - Tatiana Luna-Gomes
- Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil.,Departamento de Ciências da Natureza, Instituto de Aplicação Fernando Rodrigues da Silveira, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Sally Liechocki
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Barbara Walzog
- Walter Brendel Centre of Experimental Medicine, Department of Cardiovascular Physiology and Pathophysiology, Biomedical Center, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Ingrid Hepper
- Walter Brendel Centre of Experimental Medicine, Department of Cardiovascular Physiology and Pathophysiology, Biomedical Center, Ludwig-Maximilians-Universität München, Munich, Germany
| | | | - Patricia T Bozza
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Christianne Bandeira-Melo
- Instituto de Biofisica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Clarissa M Maya-Monteiro
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
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Auclair N, Melbouci L, St-Pierre D, Levy E. Gastrointestinal factors regulating lipid droplet formation in the intestine. Exp Cell Res 2018; 363:1-14. [PMID: 29305172 DOI: 10.1016/j.yexcr.2017.12.031] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 12/28/2017] [Accepted: 12/29/2017] [Indexed: 12/22/2022]
Abstract
Cytoplasmic lipid droplets (CLD) are considered as neutral lipid reservoirs, which protect cells from lipotoxicity. It became clear that these fascinating dynamic organelles play a role not only in energy storage and metabolism, but also in cellular lipid and protein handling, inter-organelle communication, and signaling among diverse functions. Their dysregulation is associated with multiple disorders, including obesity, liver steatosis and cardiovascular diseases. The central aim of this review is to highlight the link between intra-enterocyte CLD dynamics and the formation of chylomicrons, the main intestinal dietary lipid vehicle, after overviewing the morphology, molecular composition, biogenesis and functions of CLD.
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Affiliation(s)
- N Auclair
- Research Centre, CHU Sainte-Justine and Department of Montreal, Quebec, Canada H3T 1C5; Nutrition, Université de Montréal, Montreal, Quebec, Canada H3T 1C5
| | - L Melbouci
- Research Centre, CHU Sainte-Justine and Department of Montreal, Quebec, Canada H3T 1C5; Department of Sciences and Physical Activities, UQAM, Quebec, Canada H2X 1Y4
| | - D St-Pierre
- Research Centre, CHU Sainte-Justine and Department of Montreal, Quebec, Canada H3T 1C5; Department of Sciences and Physical Activities, UQAM, Quebec, Canada H2X 1Y4
| | - E Levy
- Research Centre, CHU Sainte-Justine and Department of Montreal, Quebec, Canada H3T 1C5; Nutrition, Université de Montréal, Montreal, Quebec, Canada H3T 1C5; Institute of Nutrition and Functional Foods (INAF), Université Laval, Quebec, Quebec, Canada G1V 0A6.
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40
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Teng O, Ang CKE, Guan XL. Macrophage-Bacteria Interactions-A Lipid-Centric Relationship. Front Immunol 2017; 8:1836. [PMID: 29326713 PMCID: PMC5742358 DOI: 10.3389/fimmu.2017.01836] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 12/05/2017] [Indexed: 11/13/2022] Open
Abstract
Macrophages are professional phagocytes at the front line of immune defenses against foreign bodies and microbial pathogens. Various bacteria, which are responsible for deadly diseases including tuberculosis and salmonellosis, are capable of hijacking this important immune cell type and thrive intracellularly, either in the cytoplasm or in specialized vacuoles. Tight regulation of cellular metabolism is critical in shaping the macrophage polarization states and immune functions. Lipids, besides being the bulk component of biological membranes, serve as energy sources as well as signaling molecules during infection and inflammation. With the advent of systems-scale analyses of genes, transcripts, proteins, and metabolites, in combination with classical biology, it is increasingly evident that macrophages undergo extensive lipid remodeling during activation and infection. Each bacterium species has evolved its own tactics to manipulate host metabolism toward its own advantage. Furthermore, modulation of host lipid metabolism affects disease susceptibility and outcome of infections, highlighting the critical roles of lipids in infectious diseases. Here, we will review the emerging roles of lipids in the complex host-pathogen relationship and discuss recent methodologies employed to probe these versatile metabolites during the infection process. An improved understanding of the lipid-centric nature of infections can lead to the identification of the Achilles' heel of the pathogens and host-directed targets for therapeutic interventions. Currently, lipid-moderating drugs are clinically available for a range of non-communicable diseases, which we anticipate can potentially be tapped into for various infections.
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Affiliation(s)
- Ooiean Teng
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Candice Ke En Ang
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Xue Li Guan
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
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Liu S, Li X, Wu Y, Duan R, Zhang J, Du F, Zhang Q, Li Y, Li N. Effects of vaspin on pancreatic β cell secretion via PI3K/Akt and NF-κB signaling pathways. PLoS One 2017; 12:e0189722. [PMID: 29240812 PMCID: PMC5730172 DOI: 10.1371/journal.pone.0189722] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 11/30/2017] [Indexed: 01/11/2023] Open
Abstract
Vaspin (visceral adipose tissue-derived serine protease inhibitor) is a recently discovered adipokine that has been implicated in diabetes mellitus and other metabolic disorders. However, the effects of vaspin on pancreatic β cell function and related mechanisms are not fully understood. Thus, the present study was performed to investigate the effects of vaspin on pancreatic β cell function and the potential underlying mechanisms. Both in vitro (rat insulinoma cells, INS-1) and in vivo (high fat diet fed rats) experiments were conducted. The results showed that vaspin significantly increased INS-1 cell secretory function. Potential mechanisms were explored using inhibitors, western blot and real-time PCR techniques. We found that vaspin increased the levels of IRS-2 mRNA and IRS-2 total protein, while decreased the serine phosphorylation level of IRS-2 protein. Moreover, vaspin increased the Akt phosphorylation protein level which was reversed by PI3K inhibitor ly294002. In addition, vaspin increased the phosphorylation levels of mTOR and p70S6K, which was inhibited by rapamycin. Meanwhile, we found that the NF-κB mRNA and protein levels were reduced after vaspin treatment, similar to the effect of NF-κB inhibitor TPCK. Furthermore, vaspin increased the glucose stimulated insulin secretion (GSIS) level, lowered blood glucose level and improved the glucose tolerance and insulin sensitivity of high fat diet fed rats. Hyperglycemic clamp test manifested that vaspin improved islet β cell function. Together, these findings provide a new understanding of the function of vaspin on pancreatic β cell and suggest that it may serve as a potential agent for the prevention and treatment of type 2 diabetes.
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Affiliation(s)
- Shiwei Liu
- Department of Endocrinology, Shanxi DAYI Hospital, Shanxi Medical University, Taiyuan, China
- Central Laboratory, Taiyuan Central Hospital, Shanxi Medical University, Taiyuan, China
- * E-mail:
| | - Xin Li
- Graduate School of Shanxi Medical University, Taiyuan, China
| | - Yaru Wu
- Central Laboratory, Taiyuan Central Hospital, Shanxi Medical University, Taiyuan, China
- Graduate School of Shanxi Medical University, Taiyuan, China
| | - Ruixue Duan
- Graduate School of Shanxi Medical University, Taiyuan, China
| | - Jiaxin Zhang
- Graduate School of Shanxi Medical University, Taiyuan, China
| | - Fang Du
- Graduate School of Shanxi Medical University, Taiyuan, China
| | - Qi Zhang
- Graduate School of Shanxi Medical University, Taiyuan, China
| | - Yuanbin Li
- Department of Endocrinology, Taiyuan Central Hospital, Shanxi Medical University, Taiyuan, China
| | - Naishi Li
- Department of Endocrinology, Key Laboratory of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science, Beijing, China
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Engin A. Fat Cell and Fatty Acid Turnover in Obesity. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 960:135-160. [PMID: 28585198 DOI: 10.1007/978-3-319-48382-5_6] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The ratio of free fatty acid (FFA) turnover decreases significantly with the expansion of white adipose tissue. Adipose tissue and dietary saturated fatty acid levels significantly correlate with an increase in fat cell size and number. Inhibition of adipose triglyceride lipase leads to an accumulation of triglyceride, whereas inhibition of hormone-sensitive lipase leads to the accumulation of diacylglycerol. The G0/G1 switch gene 2 increases lipid content in adipocytes and promotes adipocyte hypertrophy through the restriction of triglyceride turnover. Excess triacylglycerols (TAGs), sterols and sterol esters are surrounded by the phospholipid monolayer surface and form lipid droplets. Following the release of lipid droplets from endoplasmic reticulum, cytoplasmic lipid droplets increase their volume either by local TAG synthesis or by homotypic fusion. The number and the size of lipid droplet distribution is correlated with obesity. Obesity-associated adipocyte death exhibits feature of necrosis-like programmed cell death. NOD-like receptors family pyrin domain containing 3 (NLRP3) inflammasome-dependent caspase-1 activation in hypertrophic adipocytes induces obese adipocyte death by pyroptosis. Actually adipocyte death may be a prerequisite for the transition from hypertrophic to hyperplastic obesity. Major transcriptional factors, CCAAT/enhancer-binding proteins beta and delta, play a central role in the subsequent induction of critical regulators, peroxisome-proliferator-activated receptor gamma, CCAAT/enhancer-binding protein alpha and sterol regulatory element-binding protein 1, in the transcriptional control of adipogenesis in obesity.Collectively, in this chapter the concept of adipose tissue remodeling in response to adipocyte death or adipogenesis, and the complexity of lipid droplet interactions with the other cellular organelles are reviewed. Furthermore, in addition to lipid droplet growth, the functional link between the adipocyte-specific lipid droplet-associated protein and fatty acid turn-over is also debated.
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Affiliation(s)
- Atilla Engin
- Faculty of Medicine, Department of General Surgery, Gazi University, Besevler, Ankara, Turkey. .,, Mustafa Kemal Mah. 2137. Sok. 8/14, 06520, Cankaya, Ankara, Turkey.
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43
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Yang Y, Kong W, Xia Z, Xiao L, Wang S. Regulation mechanism of PDK1 on macrophage metabolism and function. Cell Biochem Funct 2016; 34:546-553. [DOI: 10.1002/cbf.3235] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 09/11/2016] [Accepted: 10/11/2016] [Indexed: 01/21/2023]
Affiliation(s)
- Yueqin Yang
- Exercise Intervention and Health Promotion Hubei Province Synergy Innovation Center; Wuhan Sports University; Wuhan Hubei China
| | - Weiwei Kong
- Graduate School; Wuhan Sports University; Wuhan Hubei China
| | - Zhi Xia
- Exercise Physiology and Biochemical Laboratory, College of Physical Education; Jinggangshan University; Ji'an Jiangxi China
| | - Lin Xiao
- School of Physical Education and Health Science; Zhaoqing University; Zhaoqing Guangdong China
| | - Song Wang
- Exercise Intervention and Health Promotion Hubei Province Synergy Innovation Center; Wuhan Sports University; Wuhan Hubei China
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Gasbarrino K, Mantzoros C, Gorgui J, Veinot JP, Lai C, Daskalopoulou SS. Circulating Chemerin Is Associated With Carotid Plaque Instability, Whereas Resistin Is Related to Cerebrovascular Symptomatology. Arterioscler Thromb Vasc Biol 2016; 36:1670-8. [PMID: 27312219 DOI: 10.1161/atvbaha.115.306741] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 05/23/2016] [Indexed: 01/08/2023]
Abstract
OBJECTIVE The rupture of unstable carotid atherosclerotic plaques is one of the main causes of cerebrovascular ischemic events. There is need for circulating markers that can predict plaque instability and risk of stroke. Proinflammatory chemerin, leptin, and resistin, along with anti-inflammatory adiponectin, are adipokines with direct influence on vascular function. We investigated the association of circulating adipokines with carotid plaque instability and cerebrovascular symptomatology. APPROACH AND RESULTS Neurologically symptomatic and asymptomatic patients (n=165) scheduled for carotid endarterectomy were recruited. Fasting blood samples were collected preoperatively; adiponectin and leptin levels were determined by radioimmunoassay; and chemerin and resistin levels were measured by enzyme-linked immunosorbent assays. The instability of plaque specimens was assessed using gold-standard histological classifications. Chemerin was significantly associated with plaque instability. The fully adjusted model, accounting for age, sex, body mass index, high-sensitivity C-reactive protein, type 2 diabetes mellitus, and circulating adiponectin, leptin, and resistin, yielded an odds ratio of 0.991 (95% confidence interval 0.985-0.998) for plaque instability per unit increase in chemerin. High leptin levels were significantly associated with presence of specific features of plaque instability. In subjects with type 2 diabetes mellitus, resistin levels were significantly elevated in symptomatic when compared with asymptomatic subjects (P=0.001) and increased the risk of cerebrovascular symptomatology (adjusted odds ratio 1.264, 95% confidence interval 1.004-1.594). CONCLUSIONS Low chemerin and high resistin levels were associated with carotid disease severity, suggesting that these adipokines may act as potential markers for plaque instability and stroke risk. Future studies are needed to assess causation between circulating adipokines and plaque instability.
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Affiliation(s)
- Karina Gasbarrino
- From the Department of Medicine, Faculty of Medicine, McGill University, Montreal, Quebec, Canada (K.G., J.G., S.S.D.); Department of Internal Medicine, Division of Endocrinology, Diabetes, and Metabolism, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, MA (C.M.); and Department of Pathology and Laboratory Medicine, University of Ottawa Heart Institute, Ottawa, Ontario, Canada (J.P.V., C.L.)
| | - Christos Mantzoros
- From the Department of Medicine, Faculty of Medicine, McGill University, Montreal, Quebec, Canada (K.G., J.G., S.S.D.); Department of Internal Medicine, Division of Endocrinology, Diabetes, and Metabolism, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, MA (C.M.); and Department of Pathology and Laboratory Medicine, University of Ottawa Heart Institute, Ottawa, Ontario, Canada (J.P.V., C.L.)
| | - Jessica Gorgui
- From the Department of Medicine, Faculty of Medicine, McGill University, Montreal, Quebec, Canada (K.G., J.G., S.S.D.); Department of Internal Medicine, Division of Endocrinology, Diabetes, and Metabolism, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, MA (C.M.); and Department of Pathology and Laboratory Medicine, University of Ottawa Heart Institute, Ottawa, Ontario, Canada (J.P.V., C.L.)
| | - John P Veinot
- From the Department of Medicine, Faculty of Medicine, McGill University, Montreal, Quebec, Canada (K.G., J.G., S.S.D.); Department of Internal Medicine, Division of Endocrinology, Diabetes, and Metabolism, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, MA (C.M.); and Department of Pathology and Laboratory Medicine, University of Ottawa Heart Institute, Ottawa, Ontario, Canada (J.P.V., C.L.)
| | - Chi Lai
- From the Department of Medicine, Faculty of Medicine, McGill University, Montreal, Quebec, Canada (K.G., J.G., S.S.D.); Department of Internal Medicine, Division of Endocrinology, Diabetes, and Metabolism, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, MA (C.M.); and Department of Pathology and Laboratory Medicine, University of Ottawa Heart Institute, Ottawa, Ontario, Canada (J.P.V., C.L.)
| | - Stella S Daskalopoulou
- From the Department of Medicine, Faculty of Medicine, McGill University, Montreal, Quebec, Canada (K.G., J.G., S.S.D.); Department of Internal Medicine, Division of Endocrinology, Diabetes, and Metabolism, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, MA (C.M.); and Department of Pathology and Laboratory Medicine, University of Ottawa Heart Institute, Ottawa, Ontario, Canada (J.P.V., C.L.).
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45
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Naylor C, Petri WA. Leptin Regulation of Immune Responses. Trends Mol Med 2016; 22:88-98. [PMID: 26776093 DOI: 10.1016/j.molmed.2015.12.001] [Citation(s) in RCA: 162] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Revised: 12/06/2015] [Accepted: 12/10/2015] [Indexed: 12/19/2022]
Abstract
Leptin is a regulatory hormone with multiple roles in the immune system. We favor the concept that leptin signaling 'licenses' various immune cells to engage in immune responses and/or to differentiate. Leptin is an inflammatory molecule that is capable of activating both adaptive and innate immunity. It can also 'enhance' immune functions, including inflammatory cytokine production in macrophages, granulocyte chemotaxis, and increased Th17 proliferation. Leptin can also 'inhibit' cells; CD4(+) T cells are inhibited from differentiating into regulatory T cells in the presence of elevated leptin, while NK cells can exhibit impaired cytotoxicity under the same circumstances. Consequently, understanding the effect of leptin signaling is important to appreciate various aspects of immune dysregulation observed in malnutrition, obesity, and autoimmunity.
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Affiliation(s)
- Caitlin Naylor
- Medical Research Council Unit, Atlantic Blvd, Serrekunda, Gambia.
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Urrutia RA, Kalinec F. Biology and pathobiology of lipid droplets and their potential role in the protection of the organ of Corti. Hear Res 2015; 330:26-38. [PMID: 25987503 PMCID: PMC5391798 DOI: 10.1016/j.heares.2015.04.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 04/17/2015] [Accepted: 04/21/2015] [Indexed: 12/20/2022]
Abstract
The current review article seeks to extend our understanding on the role of lipid droplets within the organ of Corti. In addition to presenting an overview of the current information about the origin, structure and function of lipid droplets we draw inferences from the collective body of knowledge about this cellular organelle to build a conceptual framework to better understanding their role in auditory function. This conceptual model considers that lipid droplets play a significant role in the synthesis, storage, and release of lipids and proteins for energetic use and/or modulating cell signaling pathways. We describe the role and mechanism by which LD play a role in human diseases, and we also review emerging data from our laboratory revealing the potential role of lipid droplets from Hensen cells in the auditory organ. We suggest that lipid droplets might help to develop rapidly and efficiently the resolution phase of inflammatory responses in the mammalian cochlea, preventing inflammatory damage of the delicate inner ear structures and, consequently, sensorineural hearing loss.
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Affiliation(s)
- Raul A Urrutia
- Epigenetics and Chromatin Dynamics Laboratory, Translational Epigenomic Program, Center for Individualized Medicine (CIM) Mayo Clinic, Rochester, MN 55905, USA
| | - Federico Kalinec
- Laboratory of Auditory Cell Biology, Department of Head & Neck Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
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In Situ Characterization of Splenic Brucella melitensis Reservoir Cells during the Chronic Phase of Infection in Susceptible Mice. PLoS One 2015; 10:e0137835. [PMID: 26376185 PMCID: PMC4574346 DOI: 10.1371/journal.pone.0137835] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 08/22/2015] [Indexed: 01/22/2023] Open
Abstract
Brucella are facultative intracellular Gram-negative coccobacilli that chronically infect humans as well as domestic and wild-type mammals, and cause brucellosis. Alternatively activated macrophages (M2a) induced by IL-4/IL-13 via STAT6 signaling pathways have been frequently described as a favorable niche for long-term persistence of intracellular pathogens. Based on the observation that M2a-like macrophages are induced in the spleen during the chronic phase of B. abortus infection in mice and are strongly infected in vitro, it has been suggested that M2a macrophages could be a potential in vivo niche for Brucella. In order to test this hypothesis, we used a model in which infected cells can be observed directly in situ and where the differentiation of M2a macrophages is favored by the absence of an IL-12-dependent Th1 response. We performed an in situ analysis by fluorescent microscopy of the phenotype of B. melitensis infected spleen cells from intranasally infected IL-12p40-/- BALB/c mice and the impact of STAT6 deficiency on this phenotype. Most of the infected spleen cells contained high levels of lipids and expressed CD11c and CD205 dendritic cell markers and Arginase1, but were negative for the M2a markers Fizz1 or CD301. Furthermore, STAT6 deficiency had no effect on bacterial growth or the reservoir cell phenotype in vivo, leading us to conclude that, in our model, the infected cells were not Th2-induced M2a macrophages. This characterization of B. melitensis reservoir cells could provide a better understanding of Brucella persistence in the host and lead to the design of more efficient therapeutic strategies.
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Auraptene, a Major Compound of Supercritical Fluid Extract of Phalsak (Citrus Hassaku Hort ex Tanaka), Induces Apoptosis through the Suppression of mTOR Pathways in Human Gastric Cancer SNU-1 Cells. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2015; 2015:402385. [PMID: 26351512 PMCID: PMC4550746 DOI: 10.1155/2015/402385] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2015] [Revised: 06/21/2015] [Accepted: 07/15/2015] [Indexed: 12/24/2022]
Abstract
The supercritical extraction method is a widely used process to obtain volatile and nonvolatile compounds by avoiding thermal degradation and solvent residue in the extracts. In search of phytochemicals with potential therapeutic application in gastric cancer, the supercritical fluid extract (SFE) of phalsak (Citrus hassaku Hort ex Tanaka) fruits was analyzed by gas chromatography-mass spectrometry (GC-MS). Compositional analysis in comparison with the antiproliferative activities of peel and flesh suggested auraptene as the most prominent anticancer compound against gastric cancer cells. SNU-1 cells were the most susceptible to auraptene-induced toxicity among the tested gastric cancer cell lines. Auraptene induced the death of SNU-1 cells through apoptosis, as evidenced by the increased cell population in the sub-G1 phase, the appearance of fragmented nuclei, the proteolytic cleavage of caspase-3 and poly(ADP-ribose) polymerase (PARP) protein, and depolarization of the mitochondrial membrane. Interestingly, auraptene induces an increase in the phosphorylation of Akt, which is reminiscent of the effect of rapamycin, the mTOR inhibitor that triggers a negative feedback loop on Akt/mTOR pathway. Taken together, these findings provide valuable insights into the anticancer effects of the SFE of the phalsak peel by revealing that auraptene, the major compound of it, induced apoptosis in accompanied with the inhibition of mTOR in SNU-1 cells.
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49
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Covarrubias AJ, Aksoylar HI, Horng T. Control of macrophage metabolism and activation by mTOR and Akt signaling. Semin Immunol 2015; 27:286-96. [PMID: 26360589 PMCID: PMC4682888 DOI: 10.1016/j.smim.2015.08.001] [Citation(s) in RCA: 253] [Impact Index Per Article: 28.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Revised: 08/19/2015] [Accepted: 08/19/2015] [Indexed: 12/31/2022]
Abstract
Macrophages are pleiotropic cells that assume a variety of functions depending on their tissue of residence and tissue state. They maintain homeostasis as well as coordinate responses to stresses such as infection and metabolic challenge. The ability of macrophages to acquire diverse, context-dependent activities requires their activation (or polarization) to distinct functional states. While macrophage activation is well understood at the level of signal transduction and transcriptional regulation, the metabolic underpinnings are poorly understood. Importantly, emerging studies indicate that metabolic shifts play a pivotal role in control of macrophage activation and acquisition of context-dependent effector activities. The signals that drive macrophage activation impinge on metabolic pathways, allowing for coordinate control of macrophage activation and metabolism. Here we discuss how mTOR and Akt, major metabolic regulators and targets of such activation signals, control macrophage metabolism and activation. Dysregulated macrophage activities contribute to many diseases, including infectious, inflammatory, and metabolic diseases and cancer, thus a better understanding of metabolic control of macrophage activation could pave the way to the development of new therapeutic strategies.
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Affiliation(s)
- Anthony J Covarrubias
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, 655 Huntington Ave, II-115, Boston, MA 02115, USA
| | - H Ibrahim Aksoylar
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, 655 Huntington Ave, II-115, Boston, MA 02115, USA
| | - Tiffany Horng
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, 655 Huntington Ave, II-115, Boston, MA 02115, USA.
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50
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Fazolini NPB, Cruz ALS, Werneck MBF, Viola JPB, Maya-Monteiro CM, Bozza PT. Leptin activation of mTOR pathway in intestinal epithelial cell triggers lipid droplet formation, cytokine production and increased cell proliferation. Cell Cycle 2015; 14:2667-76. [PMID: 26017929 PMCID: PMC4614828 DOI: 10.1080/15384101.2015.1041684] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Accumulating evidence suggests that obesity and enhanced inflammatory reactions are predisposing conditions for developing colon cancer. Obesity is associated with high levels of circulating leptin. Leptin is an adipocytokine that is secreted by adipose tissue and modulates immune response and inflammation. Lipid droplets (LD) are organelles involved in lipid metabolism and production of inflammatory mediators, and increased numbers of LD were observed in human colon cancer. Leptin induces the formation of LD in macrophages in a PI3K/mTOR pathway-dependent manner. Moreover, the mTOR is a serine/threonine kinase that plays a key role in cellular growth and is frequently altered in tumors. We therefore investigated the role of leptin in the modulation of mTOR pathway and regulation of lipid metabolism and inflammatory phenotype in intestinal epithelial cells (IEC-6 cells). We show that leptin promotes a dose- and time-dependent enhancement of LD formation. The biogenesis of LD was accompanied by enhanced CXCL1/CINC-1, CCL2/MCP-1 and TGF-β production and increased COX-2 expression in these cells. We demonstrated that leptin-induced increased phosphorylation of STAT3 and AKT and a dose and time-dependent mTORC activation with enhanced phosphorilation of the downstream protein P70S6K protein. Pre-treatment with rapamycin significantly inhibited leptin effects in LD formation, COX-2 and TGF-β production in IEC-6 cells. Moreover, leptin was able to stimulate the proliferation of epithelial cells on a mTOR-dependent manner. We conclude that leptin regulates lipid metabolism, cytokine production and proliferation of intestinal cells through a mechanism largely dependent on activation of the mTOR pathway, thus suggesting that leptin-induced mTOR activation may contribute to the obesity-related enhanced susceptibility to colon carcinoma.
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Affiliation(s)
- Narayana P B Fazolini
- a Laboratory of Immunopharmacology; Oswaldo Cruz Institute; FIOCRUZ ; Rio de Janeiro , Brazil
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