1
|
Taylor BC, Steinthal LH, Dias M, Yalamanchili HK, Ochsner SA, Zapata GE, Mehta NR, McKenna NJ, Young NL, Nuotio-Antar AM. Histone proteoform analysis reveals epigenetic changes in adult mouse brown adipose tissue in response to cold stress. Epigenetics Chromatin 2024; 17:12. [PMID: 38678237 PMCID: PMC11055387 DOI: 10.1186/s13072-024-00536-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Accepted: 04/09/2024] [Indexed: 04/29/2024] Open
Abstract
BACKGROUND Regulation of the thermogenic response by brown adipose tissue (BAT) is an important component of energy homeostasis with implications for the treatment of obesity and diabetes. Our preliminary analyses of RNA-Seq data uncovered many nodes representing epigenetic modifiers that are altered in BAT in response to chronic thermogenic activation. Thus, we hypothesized that chronic thermogenic activation broadly alters epigenetic modifications of DNA and histones in BAT. RESULTS Motivated to understand how BAT function is regulated epigenetically, we developed a novel method for the first-ever unbiased top-down proteomic quantitation of histone modifications in BAT and validated our results with a multi-omic approach. To test our hypothesis, wildtype male C57BL/6J mice were housed under chronic conditions of thermoneutral temperature (TN, 28°C), mild cold/room temperature (RT, 22°C), or severe cold (SC, 8°C) and BAT was analyzed for DNA methylation and histone modifications. Methylation of promoters and intragenic regions in genomic DNA decrease in response to chronic cold exposure. Integration of DNA methylation and RNA expression datasets suggest a role for epigenetic modification of DNA in regulation of gene expression in response to cold. In response to cold housing, we observe increased bulk acetylation of histones H3.2 and H4, increased histone H3.2 proteoforms with di- and trimethylation of lysine 9 (K9me2 and K9me3), and increased histone H4 proteoforms with acetylation of lysine 16 (K16ac) in BAT. CONCLUSIONS Our results reveal global epigenetically-regulated transcriptional "on" and "off" signals in murine BAT in response to varying degrees of chronic cold stimuli and establish a novel methodology to quantitatively study histones in BAT, allowing for direct comparisons to decipher mechanistic changes during the thermogenic response. Additionally, we make histone PTM and proteoform quantitation, RNA splicing, RRBS, and transcriptional footprint datasets available as a resource for future research.
Collapse
Affiliation(s)
- Bethany C Taylor
- Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology, Baylor College of Medicine, Houston, TX, USA
| | - Loic H Steinthal
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Division of Nutrition, Baylor College of Medicine, Houston, TX, USA
| | - Michelle Dias
- Department of Pediatrics, Division of Neurology, Baylor College of Medicine, Houston, TX, USA
| | - Hari Krishna Yalamanchili
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Division of Nutrition, Baylor College of Medicine, Houston, TX, USA
- Department of Pediatrics, Division of Neurology, Baylor College of Medicine, Houston, TX, USA
- Jan and Dan Neurological Research Institute, Texas Children's Hospital, Houston, TX, USA
| | - Scott A Ochsner
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Gladys E Zapata
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Division of Nutrition, Baylor College of Medicine, Houston, TX, USA
| | - Nitesh R Mehta
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Division of Nutrition, Baylor College of Medicine, Houston, TX, USA
| | - Neil J McKenna
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Nicolas L Young
- Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology, Baylor College of Medicine, Houston, TX, USA.
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA.
- Center for Precision Environmental Health, Baylor College of Medicine, Houston, TX, USA.
| | - Alli M Nuotio-Antar
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Division of Nutrition, Baylor College of Medicine, Houston, TX, USA.
| |
Collapse
|
2
|
Wang T, Zhao C, Zhang J, Li S, Zhang Y, Gong Y, Zhou Y, Yan L, Zhang S, Zhang Z, Hu H, Liu A, Bai X, Zou Z. Whitening of brown adipose tissue inhibits osteogenic differentiation via secretion of S100A8/A9. iScience 2024; 27:108857. [PMID: 38303710 PMCID: PMC10830855 DOI: 10.1016/j.isci.2024.108857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 11/20/2023] [Accepted: 01/05/2024] [Indexed: 02/03/2024] Open
Abstract
The mechanism by which brown adipose tissue (BAT) regulates bone metabolism is unclear. Here, we reveal that BAT secretes S100A8/A9, a previously unidentified BAT adipokine (batokine), to impair bone formation. Brown adipocytes-specific knockout of Rheb (RhebBAD KO), the upstream activator of mTOR, causes BAT malfunction to inhibit osteogenesis. Rheb depletion induces NF-κB dependent S100A8/A9 secretion from brown adipocytes, but not from macrophages. In wild-type mice, age-related Rheb downregulation in BAT is associated with enhanced S100A8/A9 secretion. Either batokines from RhebBAD KO mice, or recombinant S100A8/A9, inhibits osteoblast differentiation of mesenchymal stem cells in vitro by targeting toll-like receptor 4 on their surfaces. Conversely, S100A8/A9 neutralization not only rescues the osteogenesis repressed in the RhebBAD KO mice, but also alleviates age-related osteoporosis in wild-type mice. Collectively, our data revealed an unexpected BAT-bone crosstalk driven by Rheb-S100A8/A9, uncovering S100A8/A9 as a promising target for the treatment, and potentially, prevention of osteoporosis.
Collapse
Affiliation(s)
- Ting Wang
- Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Diseases, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Chaoran Zhao
- Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Diseases, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Jiahuan Zhang
- Laboratory Medicine, Guangdong Provincial People’s Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, China
| | - Shengfa Li
- Clinical Research Center, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Youming Zhang
- Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Diseases, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Yan Gong
- Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Diseases, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Yingyue Zhou
- Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Diseases, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Lei Yan
- Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Diseases, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Sheng Zhang
- Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Diseases, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Zhongmin Zhang
- Division of Spine Surgery, Department of Orthopadics, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Hongling Hu
- Department of Trauma and Joint Surgery, Shunde Hospital, Southern Medical University, Foshan, China
| | - Anling Liu
- Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Diseases, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Xiaochun Bai
- Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Diseases, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Zhipeng Zou
- Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Diseases, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| |
Collapse
|
3
|
Nance SA, Muir L, Lumeng C. Adipose tissue macrophages: Regulators of adipose tissue immunometabolism during obesity. Mol Metab 2022; 66:101642. [PMID: 36402403 PMCID: PMC9703629 DOI: 10.1016/j.molmet.2022.101642] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 11/07/2022] [Accepted: 11/14/2022] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Adipose tissue macrophages (ATMs) are a well characterized regulator of adipose tissue inflammatory tone. Previously defined by the M1 vs M2 classification, we now have a better understanding of ATM diversity that departs from the old paradigm and reports a spectrum of ATM function and phenotypes in both brown and white adipose tissue. SCOPE OF REVIEW This review provides an updated overview of ATM activation and function, ATM diversity in humans and rodents, and novel ATM functions that contribute to metabolic homeostasis and disease. MAJOR CONCLUSIONS While the paradigm that resident ATMs predominate in the lean state and obesity leads to the accumulation of lipid-associated and inflammatory ATMs still broadly remains rigorously supported, the details of this model continue to be refined and single cell data provide new insight into ATM subtypes and states.
Collapse
Affiliation(s)
- Sierra A. Nance
- Molecular & Integrative Physiology, University of Michigan Medical School, United States,Department of Pediatrics, University of Michigan Medical School, United States
| | - Lindsey Muir
- Computational Medicine and Bioinformatics, University of Michigan Medical School, United States
| | - Carey Lumeng
- Molecular & Integrative Physiology, University of Michigan Medical School, United States,Department of Pediatrics, University of Michigan Medical School, United States,Corresponding author. 109 Zina Pitcher Place, 2057 BSRB, Ann Arbor, MI 48109, United States.
| |
Collapse
|
4
|
Bertola A, Gallerand A, Ivanov S. Immune cell involvement in brown adipose tissue functions. DISCOVERY IMMUNOLOGY 2022; 1:kyac007. [PMID: 38566905 PMCID: PMC10917225 DOI: 10.1093/discim/kyac007] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 09/15/2022] [Accepted: 10/28/2022] [Indexed: 04/04/2024]
Abstract
Brown adipose tissue (BAT) contains many immune cells. The presence of macrophages, monocytes, dendritic cells, T cells, B cells, and mast cells was documented in BAT. However, in comparison to white adipose tissue, relatively little is known on the impact of immune cells on BAT function. By directly interacting with BAT stromal cells, or by secreting pro- and anti-inflammatory mediators, immune cells modulate BAT activation and subsequently influence on adaptative thermogenesis and heat generation. In the current manuscript, we will focus on the diversity and functions of BAT immune cells.
Collapse
|
5
|
Yin X, Chen Y, Ruze R, Xu R, Song J, Wang C, Xu Q. The evolving view of thermogenic fat and its implications in cancer and metabolic diseases. Signal Transduct Target Ther 2022; 7:324. [PMID: 36114195 PMCID: PMC9481605 DOI: 10.1038/s41392-022-01178-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 08/30/2022] [Accepted: 09/05/2022] [Indexed: 02/07/2023] Open
Abstract
AbstractThe incidence of metabolism-related diseases like obesity and type 2 diabetes mellitus has reached pandemic levels worldwide and increased gradually. Most of them are listed on the table of high-risk factors for malignancy, and metabolic disorders systematically or locally contribute to cancer progression and poor prognosis of patients. Importantly, adipose tissue is fundamental to the occurrence and development of these metabolic disorders. White adipose tissue stores excessive energy, while thermogenic fat including brown and beige adipose tissue dissipates energy to generate heat. In addition to thermogenesis, beige and brown adipocytes also function as dynamic secretory cells and a metabolic sink of nutrients, like glucose, fatty acids, and amino acids. Accordingly, strategies that activate and expand thermogenic adipose tissue offer therapeutic promise to combat overweight, diabetes, and other metabolic disorders through increasing energy expenditure and enhancing glucose tolerance. With a better understanding of its origins and biological functions and the advances in imaging techniques detecting thermogenesis, the roles of thermogenic adipose tissue in tumors have been revealed gradually. On the one hand, enhanced browning of subcutaneous fatty tissue results in weight loss and cancer-associated cachexia. On the other hand, locally activated thermogenic adipocytes in the tumor microenvironment accelerate cancer progression by offering fuel sources and is likely to develop resistance to chemotherapy. Here, we enumerate current knowledge about the significant advances made in the origin and physiological functions of thermogenic fat. In addition, we discuss the multiple roles of thermogenic adipocytes in different tumors. Ultimately, we summarize imaging technologies for identifying thermogenic adipose tissue and pharmacologic agents via modulating thermogenesis in preclinical experiments and clinical trials.
Collapse
|
6
|
Fernandez NC, Shinoda K. The Role of B Lymphocyte Subsets in Adipose Tissue Development, Metabolism, and Aging. Compr Physiol 2022; 12:4133-4145. [PMID: 35950657 DOI: 10.1002/cphy.c220006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Adipose tissue contains resident B lymphocytes (B cells) with varying immune functions and mechanisms, depending on the adipose depot type and location. The heterogeneity of B cells and their functions affect the immunometabolism of the adipose tissue in aging and age-associated metabolic disorders. B cells exist in categorizations of subsets that have developmental or phenotypic differences with varying functionalities. Subsets can be categorized as either protective or pathogenic depending on their secretion profile or involvement in metabolic maintenance. In this article, we summarized recent finding on the B cell heterogeneity and discuss how we can utilize our current knowledge of adipose resident B lymphocytes for potential treatment for age-associated metabolic disorders. © 2022 American Physiological Society. Compr Physiol 12: 1-13, 2022.
Collapse
Affiliation(s)
- Nicole C Fernandez
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Kosaku Shinoda
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York, USA
- Department of Medicine, Division of Endocrinology & Diabetes, Albert Einstein College of Medicine, Bronx, New York, USA
- Fleischer Institute for Diabetes and Metabolism, Bronx, New York, USA
| |
Collapse
|
7
|
Yamamoto S, Mizoue T, Tanaka A, Oshiro Y, Inamura N, Konishi M, Ozeki M, Miyo K, Sugiura W, Sugiyama H, Ohmagari N. Sex-associated differences between BMI and SARS-CoV-2 antibody titers following the BNT162b2 vaccine. Obesity (Silver Spring) 2022; 30:999-1003. [PMID: 35226399 PMCID: PMC9088326 DOI: 10.1002/oby.23417] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 02/15/2022] [Accepted: 02/25/2022] [Indexed: 12/02/2022]
Abstract
OBJECTIVE This study investigated the sex-associated difference in the impact of obesity on antibody response to a COVID-19 vaccine. METHODS This study included 2,435 health care workers who received two doses of the BioNTech, Pfizer (BNT162b2) vaccine and participated in a serological survey, during which they were tested for anti-SARS-CoV-2 spike immunoglobin G (IgG) antibodies and asked for information on height, weight, and vaccination history via a questionnaire. Multivariable linear regression analysis was used to estimate the geometric mean titers (GMT) of antibodies for each sex and BMI category. RESULTS The relationship between BMI and anti-SARS-CoV-2 spike IgG titers markedly differed by sex (p value for interaction = 0.04). Spike IgG antibody titers tended to decrease with increasing BMI in men (p value for trend = 0.03); GMT (95% CI) were 6,093 (4,874-7,618) and 4,655 (3,795-5,708) for BMI < 18.5 and ≥30 kg/m2 , respectively. In contrast, spike IgG antibody titers did not significantly differ across BMI categories in women (p value for for trend = 0.62); GMT (95% CI) were 6,171 (5,714-6,665) and 5,506 (4,404-6,883) for BMI <18.5 and ≥30, respectively. CONCLUSIONS Higher BMI was associated with lower titers of SARS-CoV-2 spike antibodies in men, but not in women, suggesting the need for careful monitoring of vaccine efficacy in men with obesity, who are at high risk of severe COVID-19 outcomes.
Collapse
Affiliation(s)
- Shohei Yamamoto
- Department of Epidemiology and Prevention, Center for Clinical SciencesNational Center for Global Health and MedicineTokyoJapan
| | - Tetsuya Mizoue
- Department of Epidemiology and Prevention, Center for Clinical SciencesNational Center for Global Health and MedicineTokyoJapan
| | - Akihito Tanaka
- Department of Laboratory TestingCenter Hospital of the National Center for the Global Health and MedicineTokyoJapan
| | - Yusuke Oshiro
- Department of Laboratory TestingCenter Hospital of the National Center for the Global Health and MedicineTokyoJapan
| | - Natsumi Inamura
- Department of Laboratory TestingCenter Hospital of the National Center for the Global Health and MedicineTokyoJapan
| | - Maki Konishi
- Department of Epidemiology and Prevention, Center for Clinical SciencesNational Center for Global Health and MedicineTokyoJapan
| | - Mitsuru Ozeki
- Department of Laboratory TestingCenter Hospital of the National Center for the Global Health and MedicineTokyoJapan
| | - Kengo Miyo
- Center for Medical Informatics IntelligenceNational Center for Global Health and MedicineTokyoJapan
| | - Wataru Sugiura
- Center for Clinical SciencesNational Center for Global Health and MedicineTokyoJapan
| | - Haruhito Sugiyama
- Department of Respiratory MedicineCenter Hospital of the National Center for the Global Health and MedicineTokyoJapan
| | - Norio Ohmagari
- Disease Control and Prevention CenterNational Center for Global Health and MedicineTokyoJapan
| |
Collapse
|
8
|
Agueda-Oyarzabal M, Emanuelli B. Immune Cells in Thermogenic Adipose Depots: The Essential but Complex Relationship. Front Endocrinol (Lausanne) 2022; 13:839360. [PMID: 35360060 PMCID: PMC8963988 DOI: 10.3389/fendo.2022.839360] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Accepted: 01/28/2022] [Indexed: 01/09/2023] Open
Abstract
Brown adipose tissue (BAT) is a unique organ in mammals capable of dissipating energy in form of heat. Additionally, white adipose tissue (WAT) can undergo browning and perform thermogenesis. In recent years, the research community has aimed to harness thermogenic depot functions for new therapeutic strategies against obesity and the metabolic syndrome; hence a comprehensive understanding of the thermogenic fat microenvironment is essential. Akin to WAT, immune cells also infiltrate and reside within the thermogenic adipose tissues and perform vital functions. As highly plastic organs, adipose depots rely on crucial interplay with these tissue resident cells to conserve their healthy state. Evidence has accumulated to show that different immune cell populations contribute to thermogenic adipose tissue homeostasis and activation through complex communicative networks. Furthermore, new studies have identified -but still not fully characterized further- numerous immune cell populations present in these depots. Here, we review the current knowledge of this emerging field by describing the immune cells that sway the thermogenic adipose depots, and the complex array of communications that influence tissue performance.
Collapse
|
9
|
Pasquarelli-do-Nascimento G, Machado SA, de Carvalho JMA, Magalhães KG. Obesity and adipose tissue impact on T-cell response and cancer immune checkpoint blockade therapy. IMMUNOTHERAPY ADVANCES 2022; 2:ltac015. [PMID: 36033972 PMCID: PMC9404253 DOI: 10.1093/immadv/ltac015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 06/23/2022] [Indexed: 11/17/2022] Open
Abstract
Many different types of cancer are now well known to have increased occurrence or severity in individuals with obesity. The influence of obesity on cancer and the immune cells in the tumor microenvironment has been thought to be a pleiotropic effect. As key endocrine and immune organs, the highly plastic adipose tissues play crucial roles in obesity pathophysiology, as they show alterations according to environmental cues. Adipose tissues of lean subjects present mostly anti-inflammatory cells that are crucial in tissue remodeling, favoring uncoupling protein 1 expression and non-shivering thermogenesis. Oppositely, obese adipose tissues display massive proinflammatory immune cell infiltration, dying adipocytes, and enhanced crown-like structure formation. In this review, we discuss how obesity can lead to derangements and dysfunctions in antitumor CD8+ T lymphocytes dysfunction. Moreover, we explain how obesity can affect the efficiency of cancer immunotherapy, depicting the mechanisms involved in this process. Cancer immunotherapy management includes monoclonal antibodies targeting the immune checkpoint blockade. Exhausted CD8+ T lymphocytes show elevated programmed cell death-1 (PD-1) expression and highly glycolytic tumors tend to show a good response to anti-PD-1/PD-L1 immunotherapy. Although obesity is a risk factor for the development of several neoplasms and is linked with increased tumor growth and aggressiveness, obesity is also related to improved response to cancer immunotherapy, a phenomenon called the obesity paradox. However, patients affected by obesity present higher incidences of adverse events related to this therapy. These limitations highlight the necessity of a deeper investigation of factors that influence the obesity paradox to improve the application of these therapies.
Collapse
Affiliation(s)
| | - Sabrina Azevedo Machado
- Laboratory of Immunology and Inflammation, Department of Cell Biology, University of Brasilia , DF , Brazil
| | | | - Kelly Grace Magalhães
- Laboratory of Immunology and Inflammation, Department of Cell Biology, University of Brasilia , DF , Brazil
| |
Collapse
|
10
|
Adipose Tissue Immunometabolism and Apoptotic Cell Clearance. Cells 2021; 10:cells10092288. [PMID: 34571937 PMCID: PMC8470283 DOI: 10.3390/cells10092288] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 08/26/2021] [Accepted: 08/30/2021] [Indexed: 12/19/2022] Open
Abstract
The safe removal of apoptotic debris by macrophages—often referred to as efferocytosis—is crucial for maintaining tissue integrity and preventing self-immunity or tissue damaging inflammation. Macrophages clear tissues of hazardous materials from dying cells and ultimately adopt a pro-resolving activation state. However, adipocyte apoptosis is an inflammation-generating process, and the removal of apoptotic adipocytes by so-called adipose tissue macrophages triggers a sequence of events that lead to meta-inflammation and obesity-associated metabolic diseases. Signals that allow apoptotic cells to control macrophage immune functions are complex and involve metabolites released by the apoptotic cells and also metabolites produced by the macrophages during the digestion of apoptotic cell contents. This review provides a concise summary of the adipocyte-derived metabolites that potentially control adipose tissue macrophage immune functions and, hence, may induce or alleviate adipose tissue inflammation.
Collapse
|
11
|
Mincham KT, Panchal K, Hart PH, Lucas RM, Feelisch M, Weller RB, Matthews VB, Strickland DH, Gorman S. Metabolic dysfunction induced by a high-fat diet modulates hematopoietic stem and myeloid progenitor cells in brown adipose tissue of mice. Immunol Cell Biol 2021; 99:749-766. [PMID: 33866598 DOI: 10.1111/imcb.12460] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 02/05/2021] [Accepted: 04/15/2021] [Indexed: 11/29/2022]
Abstract
Brown adipose tissue (BAT) may be an important metabolic regulator of whole-body glucose. While important roles have been ascribed to macrophages in regulating metabolic functions in BAT, little is known of the roles of other immune cells subsets, particularly dendritic cells (DCs). Eating a high-fat diet may compromise the development of hematopoietic stem and progenitor cells (HSPCs)-which give rise to DCs-in bone marrow, with less known of its effects in BAT. We have previously demonstrated that ongoing exposure to low-dose ultraviolet radiation (UVR) significantly reduced the 'whitening' effect of eating a high-fat diet upon interscapular (i) BAT of mice. Here, we examined whether this observation may be linked to changes in the phenotype of HSPCs and myeloid-derived immune cells in iBAT and bone marrow of mice using 12-colour flow cytometry. Many HSPC subsets declined in both iBAT and bone marrow with increasing metabolic dysfunction. Conversely, with rising adiposity and metabolic dysfunction, conventional DCs (cDCs) increased in both of these tissues. When compared with a low-fat diet, consumption of a high-fat diet significantly reduced proportions of myeloid, common myeloid and megakaryocyte-erythrocyte progenitors in iBAT, and short-term hematopoietic stem cells in bone marrow. In mice fed the high-fat diet, exposure to low-dose UVR significantly reduced proportions of cDCs in iBAT, independently of nitric oxide release from irradiated skin [blocked using the scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide potassium salt (cPTIO)], but did not significantly modify HSPC subsets in either tissue. Further studies are needed to determine whether changes in these cell populations contribute towards metabolic dysfunction .
Collapse
Affiliation(s)
- Kyle T Mincham
- Telethon Kids Institute, University of Western Australia, Perth, Australia
| | - Kunjal Panchal
- Telethon Kids Institute, University of Western Australia, Perth, Australia
| | - Prue H Hart
- Telethon Kids Institute, University of Western Australia, Perth, Australia
| | - Robyn M Lucas
- National Centre for Epidemiology and Population Health, Research School of Population Health, Australian National University, Canberra, Australian Capital Territory, Australia.,Centre for Ophthalmology and Visual Science, University of Western Australia, Perth, Australia
| | - Martin Feelisch
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, UK
| | - Richard B Weller
- University of Edinburgh, MRC Centre for Inflammation Research, Edinburgh, Scotland
| | - Vance B Matthews
- School of Biomedical Science - Royal Perth Hospital Unit, The University of Western Australia, Perth, Australia
| | | | - Shelley Gorman
- Telethon Kids Institute, University of Western Australia, Perth, Australia
| |
Collapse
|
12
|
Abstract
Cardiovascular diseases are the leading cause of death worldwide. Overweight and obesity are strongly associated with comorbidities such as hypertension and insulin resistance, which collectively contribute to the development of cardiovascular diseases and resultant morbidity and mortality. Forty-two percent of adults in the United States are obese, and a total of 1.9 billion adults worldwide are overweight or obese. These alarming numbers, which continue to climb, represent a major health and economic burden. Adipose tissue is a highly dynamic organ that can be classified based on the cellular composition of different depots and their distinct anatomical localization. Massive expansion and remodeling of adipose tissue during obesity differentially affects specific adipose tissue depots and significantly contributes to vascular dysfunction and cardiovascular diseases. Visceral adipose tissue accumulation results in increased immune cell infiltration and secretion of vasoconstrictor mediators, whereas expansion of subcutaneous adipose tissue is less harmful. Therefore, fat distribution more than overall body weight is a key determinant of the risk for cardiovascular diseases. Thermogenic brown and beige adipose tissue, in contrast to white adipose tissue, is associated with beneficial effects on the vasculature. The relationship between the type of adipose tissue and its influence on vascular function becomes particularly evident in the context of the heterogenous phenotype of perivascular adipose tissue that is strongly location dependent. In this review, we address the abnormal remodeling of specific adipose tissue depots during obesity and how this critically contributes to the development of hypertension, endothelial dysfunction, and vascular stiffness. We also discuss the local and systemic roles of adipose tissue derived secreted factors and increased systemic inflammation during obesity and highlight their detrimental impact on cardiovascular health.
Collapse
Affiliation(s)
- Mascha Koenen
- Laboratory of Molecular Metabolism, The Rockefeller University, New York (M.K., P.C.)
| | - Michael A Hill
- Dalton Cardiovascular Research Center, University of Missouri, Columbia (M.A.H., J.R.S.)
- Department of Medical Pharmacology and Physiology (M.A.H., J.R.S.), University of Missouri School of Medicine, Columbia
| | - Paul Cohen
- Laboratory of Molecular Metabolism, The Rockefeller University, New York (M.K., P.C.)
| | - James R Sowers
- Dalton Cardiovascular Research Center, University of Missouri, Columbia (M.A.H., J.R.S.)
- Department of Medical Pharmacology and Physiology (M.A.H., J.R.S.), University of Missouri School of Medicine, Columbia
- Diabetes and Cardiovascular Center (J.R.S.), University of Missouri School of Medicine, Columbia
- Department of Medicine (J.R.S.), University of Missouri School of Medicine, Columbia
| |
Collapse
|
13
|
Brown Adipose Tissue and Its Role in Insulin and Glucose Homeostasis. Int J Mol Sci 2021; 22:ijms22041530. [PMID: 33546400 PMCID: PMC7913527 DOI: 10.3390/ijms22041530] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 01/21/2021] [Accepted: 02/01/2021] [Indexed: 12/15/2022] Open
Abstract
The increased worldwide prevalence of obesity, insulin resistance, and their related metabolic complications have prompted the scientific world to search for new possibilities to combat obesity. Brown adipose tissue (BAT), due to its unique protein uncoupling protein 1 (UPC1) in the inner membrane of the mitochondria, has been acknowledged as a promising approach to increase energy expenditure. Activated brown adipocytes dissipate energy, resulting in heat production. In other words, BAT burns fat and increases the metabolic rate, promoting a negative energy balance. Moreover, BAT alleviates metabolic complications like dyslipidemia, impaired insulin secretion, and insulin resistance in type 2 diabetes. The aim of this review is to explore the role of BAT in total energy expenditure, as well as lipid and glucose homeostasis, and to discuss new possible activators of brown adipose tissue in humans to treat obesity and metabolic disorders.
Collapse
|
14
|
Crouch M, Al-Shaer A, Shaikh SR. Hormonal Dysregulation and Unbalanced Specialized Pro-Resolving Mediator Biosynthesis Contribute toward Impaired B Cell Outcomes in Obesity. Mol Nutr Food Res 2021; 65:e1900924. [PMID: 32112513 PMCID: PMC8627245 DOI: 10.1002/mnfr.201900924] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 02/09/2020] [Indexed: 12/16/2022]
Abstract
Diet-induced obesity is associated with impaired B-cell-driven humoral immunity, which coincides with chronic inflammation and has consequences for responses to infections and vaccinations. Key nutritional, cellular, and molecular mechanisms by which obesity may impair aspects of humoral immunity such as B cell development, class switch recombination, and formation of long-lived antibody secreting cells are reviewed. A key theme to emerge is the central role of white adipose tissue on the formation and function of pro-inflammatory B cell subsets that exacerbate insulin resistance. The underlying role of select hormones such as leptin is highlighted, which may be driving the formation of pro-inflammatory B cells in the absence of antigen stimulation. This review also extensively covers the regulatory role of lipid metabolites such as prostaglandins and specialized pro-resolving mediators (SPMs) that are synthesized from polyunsaturated fatty acids. Notably, SPM biosynthesis is impaired in obesity and contributes toward impaired antibody production. Future directions for research, including avenues for therapeutic intervention, are included.
Collapse
Affiliation(s)
- Miranda Crouch
- Department of Nutrition, Gillings School of Global Public Health and School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Abrar Al-Shaer
- Department of Nutrition, Gillings School of Global Public Health and School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Saame Raza Shaikh
- Department of Nutrition, Gillings School of Global Public Health and School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| |
Collapse
|
15
|
AlZaim I, Hammoud SH, Al-Koussa H, Ghazi A, Eid AH, El-Yazbi AF. Adipose Tissue Immunomodulation: A Novel Therapeutic Approach in Cardiovascular and Metabolic Diseases. Front Cardiovasc Med 2020; 7:602088. [PMID: 33282920 PMCID: PMC7705180 DOI: 10.3389/fcvm.2020.602088] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 10/22/2020] [Indexed: 12/12/2022] Open
Abstract
Adipose tissue is a critical regulator of systemic metabolism and bodily homeostasis as it secretes a myriad of adipokines, including inflammatory and anti-inflammatory cytokines. As the main storage pool of lipids, subcutaneous and visceral adipose tissues undergo marked hypertrophy and hyperplasia in response to nutritional excess leading to hypoxia, adipokine dysregulation, and subsequent low-grade inflammation that is characterized by increased infiltration and activation of innate and adaptive immune cells. The specific localization, physiology, susceptibility to inflammation and the heterogeneity of the inflammatory cell population of each adipose depot are unique and thus dictate the possible complications of adipose tissue chronic inflammation. Several lines of evidence link visceral and particularly perivascular, pericardial, and perirenal adipose tissue inflammation to the development of metabolic syndrome, insulin resistance, type 2 diabetes and cardiovascular diseases. In addition to the implication of the immune system in the regulation of adipose tissue function, adipose tissue immune components are pivotal in detrimental or otherwise favorable adipose tissue remodeling and thermogenesis. Adipose tissue resident and infiltrating immune cells undergo metabolic and morphological adaptation based on the systemic energy status and thus a better comprehension of the metabolic regulation of immune cells in adipose tissues is pivotal to address complications of chronic adipose tissue inflammation. In this review, we discuss the role of adipose innate and adaptive immune cells across various physiological and pathophysiological states that pertain to the development or progression of cardiovascular diseases associated with metabolic disorders. Understanding such mechanisms allows for the exploitation of the adipose tissue-immune system crosstalk, exploring how the adipose immune system might be targeted as a strategy to treat cardiovascular derangements associated with metabolic dysfunctions.
Collapse
Affiliation(s)
- Ibrahim AlZaim
- Department of Pharmacology and Toxicology, American University of Beirut, Beirut, Lebanon
- Department of Biochemistry and Molecular Genetics, American University of Beirut, Beirut, Lebanon
| | - Safaa H Hammoud
- Department of Pharmacology and Therapeutics, Beirut Arab University, Beirut, Lebanon
| | - Houssam Al-Koussa
- Department of Pharmacology and Toxicology, American University of Beirut, Beirut, Lebanon
| | - Alaa Ghazi
- Department of Pharmacology and Toxicology, American University of Beirut, Beirut, Lebanon
| | - Ali H Eid
- Department of Pharmacology and Therapeutics, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
- Department of Basic Medical Sciences, College of Medicine, Qatar University, Doha, Qatar
- Biomedical and Pharmaceutical Research Unit, QU Health, Qatar University, Doha, Qatar
| | - Ahmed F El-Yazbi
- Department of Pharmacology and Toxicology, American University of Beirut, Beirut, Lebanon
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| |
Collapse
|
16
|
Abstract
The immune system plays an important role in obesity-induced adipose tissue inflammation and the resultant metabolic dysfunction, which can lead to hypertension, dyslipidemia, and insulin resistance and their downstream sequelae of type 2 diabetes mellitus and cardiovascular disease. While macrophages are the most abundant immune cell type in adipose tissue, other immune cells are also present, such as B cells, which play important roles in regulating adipose tissue inflammation. This brief review will overview B-cell subsets, describe their localization in various adipose depots and summarize our knowledge about the function of these B-cell subsets in regulating adipose tissue inflammation, obesity-induced metabolic dysfunction and atherosclerosis.
Collapse
Affiliation(s)
- Prasad Srikakulapu
- From the Cardiovascular Research Center, Cardiovascular Division, Department of Medicine, University of Virginia, Charlottesville
| | - Coleen A McNamara
- From the Cardiovascular Research Center, Cardiovascular Division, Department of Medicine, University of Virginia, Charlottesville
| |
Collapse
|
17
|
Fischer AW, de Jong JMA, Sass F, Schlein C, Heeren J, Petrovic N. Thermoneutrality-Induced Macrophage Accumulation in Brown Adipose Tissue Does Not Impair the Tissue's Competence for Cold-Induced Thermogenic Recruitment. Front Endocrinol (Lausanne) 2020; 11:568682. [PMID: 33193086 PMCID: PMC7662517 DOI: 10.3389/fendo.2020.568682] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 09/22/2020] [Indexed: 01/08/2023] Open
Abstract
Brown adipose tissue from mice living under conditions approaching human thermal and nutritional conditions (prolonged exposure to thermoneutral temperature and to an energy-rich (high-fat, high-sugar) diet) - referred to as "physiologically humanized" mice, displays morphological and molecular characteristics significantly different from those observed in young, chow-fed mice maintained at room temperature - referred to as "standard" mice. Here, we further examined brown fat from physiologically humanized and standard mice, as well as from mice exposed to thermoneutrality for a long time but not to an energy-rich diet - referred to here as "long-term thermoneutral" mice. Global transcriptome analysis of brown fat revealed that genes that were the most upregulated in brown fat of thermoneutral mice (both physiologically humanized and long-term thermoneutral) were those related to inflammatory processes, including genes expressed selectively in macrophages. Cellular and molecular analyses confirmed that brown fat from thermoneutral mice was heavily infiltrated by macrophages, predominantly organized into crown-like structures. However, despite this, the brown fat of thermoneutral mice retained full competence to attain the greatest possible recruitment state and became macrophage-depleted during the process of cold acclimation. Thus, profound macrophage accumulation does not influence the thermogenic recruitment competence of brown fat.
Collapse
Affiliation(s)
- Alexander W. Fischer
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jasper M. A. de Jong
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Frederike Sass
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christian Schlein
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Joerg Heeren
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Natasa Petrovic
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
- *Correspondence: Natasa Petrovic,
| |
Collapse
|
18
|
Vercalsteren E, Vranckx C, Frederix L, Lox M, Lijnen HR, Scroyen I, Hemmeryckx B. Advanced-age C57BL/6JRj mice do not develop obesity upon western-type diet exposure. Adipocyte 2019; 8:105-113. [PMID: 30860940 PMCID: PMC6768272 DOI: 10.1080/21623945.2019.1590893] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 02/06/2019] [Accepted: 02/13/2019] [Indexed: 12/16/2022] Open
Abstract
Obesity has become a global health-threat for every age group. It is well known that young mice (10-12 weeks of age) fed a western-type diet (WD) become obese and develop higher cholesterol levels and liver steatosis whereas insulin sensitivity is reduced. Less is known, however, about the effect of a WD on advanced-age mice. Therefore, 10 week-old (young) and 22 month-old (advanced-age), male C57BL/6JRj mice were kept on either a WD or a control diet (SFD) for 15 weeks. In contrast to young mice, advanced-age mice on WD did not show a higher body weight or adipose tissue (AT)-masses, suggesting a protection against diet-induced obesity. Furthermore, plasma adiponectin and leptin levels were not affected upon WD-feeding. A WD, however, did induce more hepatic lipid accumulation as well as increased hepatic expression of the macrophage marker F4/80, in advanced-age mice. There were no significant differences in mRNA levels of uncoupling protein-1 or F4/80 in brown AT (BAT) or of several intestinal integrity markers in colon suggesting that the protection against obesity is not due to excessive BAT or to impaired intestinal absorption of fat. Thus, advanced-age mice, in contrast to their younger counterparts, appeared to be protected against diet-induced obesity.
Collapse
Affiliation(s)
- Ellen Vercalsteren
- Center for Molecular and Vascular Biology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
| | - Christine Vranckx
- Center for Molecular and Vascular Biology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
| | - Liesbeth Frederix
- Center for Molecular and Vascular Biology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
| | - Marleen Lox
- Center for Molecular and Vascular Biology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
| | - H. Roger Lijnen
- Center for Molecular and Vascular Biology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
| | - Ilse Scroyen
- Center for Molecular and Vascular Biology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
| | - Bianca Hemmeryckx
- Center for Molecular and Vascular Biology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
| |
Collapse
|
19
|
Bolus WR, Hasty AH. Contributions of innate type 2 inflammation to adipose function. J Lipid Res 2019; 60:1698-1709. [PMID: 29891508 PMCID: PMC6795076 DOI: 10.1194/jlr.r085993] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Revised: 05/25/2018] [Indexed: 12/17/2022] Open
Abstract
A critical contributor to the health consequences of the obesity epidemic is dysregulated adipose tissue (AT) homeostasis. While white, brown, and beige AT function is altered in obesity-related disease, white AT is marked by progressive inflammation and adipocyte dysfunction and has been the focus of extensive "immunometabolism" research in the past decade. The exact triggering events initiating and sustaining AT inflammation are still under study, but it has been shown that reducing inflammation improves insulin action in AT. Scientific efforts seeking interventions to mitigate obesity-associated AT inflammation continue, and many groups are now determining how lean healthy AT homeostasis is maintained in order to leverage these mechanisms as therapeutic targets. Such studies have revealed that an elaborate network of immune cells, cytokines, and other cellular mediators coordinate AT function. Recent studies elucidated the involvement of the innate immune system in AT homeostasis (e.g., beiging and insulin sensitivity), including M2-like macrophages, eosinophils, innate lymphoid type 2 cells, and several others. In this review, we summarize the existing literature on innate type 2 inflammation in AT; additionally, we draw attention to areas of debate where seemingly conflicting data promises to yield more surprising and elegant biology as studies continue to dissect AT physiology.
Collapse
Affiliation(s)
- W Reid Bolus
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville TN 37232
| | - Alyssa H Hasty
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville TN 37232
- Veterans Affairs Tennessee Valley Healthcare System, Nashville TN 37212
| |
Collapse
|
20
|
Liu R, Nikolajczyk BS. Tissue Immune Cells Fuel Obesity-Associated Inflammation in Adipose Tissue and Beyond. Front Immunol 2019; 10:1587. [PMID: 31379820 PMCID: PMC6653202 DOI: 10.3389/fimmu.2019.01587] [Citation(s) in RCA: 177] [Impact Index Per Article: 35.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 06/25/2019] [Indexed: 12/12/2022] Open
Abstract
Obesity-associated inflammation stems from a combination of cell-intrinsic changes of individual immune cell subsets and the dynamic crosstalk amongst a broad array of immune cells. Although much of the focus of immune cell contributions to metabolic disease has focused on adipose tissue-associated cells, these potent sources of inflammation inhabit other metabolic regulatory tissues, including liver and gut, and recirculate to promote systemic inflammation and thus obesity comorbidities. Tissue-associated immune cells, especially T cell subpopulations, have become a hotspot of inquiry based on their contributions to obesity, type 2 diabetes, non-alcoholic fatty liver diseases and certain types of cancers. The cell-cell interactions that take place under the stress of obesity are mediated by intracellular contact and cytokine production, and constitute a complicated network that drives the phenotypic alterations of immune cells and perpetuates a feed-forward loop of metabolic decline. Herein we discuss immune cell functions in various tissues and obesity-associated cancers from the viewpoint of inflammation. We also emphasize recent advances in the understanding of crosstalk amongst immune cell subsets under obese conditions, and suggest future directions for focused investigations with clinical relevance.
Collapse
Affiliation(s)
- Rui Liu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY, United States
| | - Barbara S. Nikolajczyk
- Department of Pharmacology and Nutritional Sciences, Barnstable Brown Diabetes and Obesity Research Center, University of Kentucky, Lexington, KY, United States
| |
Collapse
|
21
|
Zhao Y, Lin L, Li J, Xiao Z, Chen B, Wan L, Li M, Wu X, Hin Cho C, Shen J. CD4+ T cells in obesity and obesity-associated diseases. Cell Immunol 2018; 332:1-6. [DOI: 10.1016/j.cellimm.2018.08.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 07/29/2018] [Accepted: 08/20/2018] [Indexed: 02/08/2023]
|