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Huang T, Lu Z, Wang Z, Cheng L, Gao L, Gao J, Zhang N, Geng CA, Zhao X, Wang H, Wong CW, Yeung KWK, Pan H, Lu WW, Guan M. Targeting adipocyte ESRRA promotes osteogenesis and vascular formation in adipocyte-rich bone marrow. Nat Commun 2024; 15:3769. [PMID: 38704393 PMCID: PMC11069533 DOI: 10.1038/s41467-024-48255-8] [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: 07/18/2023] [Accepted: 04/23/2024] [Indexed: 05/06/2024] Open
Abstract
Excessive bone marrow adipocytes (BMAds) accumulation often occurs under diverse pathophysiological conditions associated with bone deterioration. Estrogen-related receptor α (ESRRA) is a key regulator responding to metabolic stress. Here, we show that adipocyte-specific ESRRA deficiency preserves osteogenesis and vascular formation in adipocyte-rich bone marrow upon estrogen deficiency or obesity. Mechanistically, adipocyte ESRRA interferes with E2/ESR1 signaling resulting in transcriptional repression of secreted phosphoprotein 1 (Spp1); yet positively modulates leptin expression by binding to its promoter. ESRRA abrogation results in enhanced SPP1 and decreased leptin secretion from both visceral adipocytes and BMAds, concertedly dictating bone marrow stromal stem cell fate commitment and restoring type H vessel formation, constituting a feed-forward loop for bone formation. Pharmacological inhibition of ESRRA protects obese mice against bone loss and high marrow adiposity. Thus, our findings highlight a therapeutic approach via targeting adipocyte ESRRA to preserve bone formation especially in detrimental adipocyte-rich bone milieu.
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Affiliation(s)
- Tongling Huang
- Research Center for Human Tissues and Organs Degeneration, Institute of Biomedicine and Biotechnology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Zhaocheng Lu
- Research Center for Human Tissues and Organs Degeneration, Institute of Biomedicine and Biotechnology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Zihui Wang
- Research Center for Human Tissues and Organs Degeneration, Institute of Biomedicine and Biotechnology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Lixin Cheng
- Guangdong Provincial Clinical Research Center for Geriatrics, Shenzhen Clinical Research Center for Geriatrics, Shenzhen People's Hospital, Shenzhen, China
| | - Lu Gao
- Research Center for Human Tissues and Organs Degeneration, Institute of Biomedicine and Biotechnology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Jun Gao
- Research Center for Human Tissues and Organs Degeneration, Institute of Biomedicine and Biotechnology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Ning Zhang
- Neuroscience Center, Shantou University Medical College, Shantou, China
| | - Chang-An Geng
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China
| | - Xiaoli Zhao
- Research Center for Human Tissues and Organs Degeneration, Institute of Biomedicine and Biotechnology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Huaiyu Wang
- Research Center for Human Tissues and Organs Degeneration, Institute of Biomedicine and Biotechnology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | | | - Kelvin W K Yeung
- Department of Orthopaedics and Traumatology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Haobo Pan
- Research Center for Human Tissues and Organs Degeneration, Institute of Biomedicine and Biotechnology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - William Weijia Lu
- Faculty of Pharmaceutical Sciences, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Min Guan
- Research Center for Human Tissues and Organs Degeneration, Institute of Biomedicine and Biotechnology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.
- University of Chinese Academy of Sciences, Beijing, China.
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Marinelli Busilacchi E, Morsia E, Poloni A. Bone Marrow Adipose Tissue. Cells 2024; 13:724. [PMID: 38727260 PMCID: PMC11083575 DOI: 10.3390/cells13090724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 04/19/2024] [Accepted: 04/19/2024] [Indexed: 05/13/2024] Open
Abstract
Bone marrow (BM) acts as a dynamic organ within the bone cavity, responsible for hematopoiesis, skeletal remodeling, and immune system control. Bone marrow adipose tissue (BMAT) was long simply considered a filler of space, but now it is known that it instead constitutes an essential element of the BM microenvironment that participates in homeostasis, influences bone health and bone remodeling, alters hematopoietic stem cell functions, contributes to the commitment of mesenchymal stem cells, provides effects to immune homeostasis and defense against infections, and participates in energy metabolism and inflammation. BMAT has emerged as a significant contributor to the development and progression of various diseases, shedding light on its complex relationship with health. Notably, BMAT has been implicated in metabolic disorders, hematological malignancies, and skeletal conditions. BMAT has been shown to support the proliferation of tumor cells in acute myeloid leukemia and niche adipocytes have been found to protect cancer cells against chemotherapy, contributing to treatment resistance. Moreover, BMAT's impact on bone density and remodeling can lead to conditions like osteoporosis, where high levels of BMAT are inversely correlated with bone mineral density, increasing the risk of fractures. BMAT has also been associated with diabetes, obesity, and anorexia nervosa, with varying effects on individuals depending on their weight and health status. Understanding the interaction between adipocytes and different diseases may lead to new therapeutic strategies.
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Affiliation(s)
- Elena Marinelli Busilacchi
- Hematology Laboratory, Department of Clinical and Molecular Sciences, DISCLIMO, Università Politecnica delle Marche, 60126 Ancona, Italy; (E.M.B.); (E.M.)
| | - Erika Morsia
- Hematology Laboratory, Department of Clinical and Molecular Sciences, DISCLIMO, Università Politecnica delle Marche, 60126 Ancona, Italy; (E.M.B.); (E.M.)
- Hematology, AOU delle Marche, 60126 Ancona, Italy
| | - Antonella Poloni
- Hematology Laboratory, Department of Clinical and Molecular Sciences, DISCLIMO, Università Politecnica delle Marche, 60126 Ancona, Italy; (E.M.B.); (E.M.)
- Hematology, AOU delle Marche, 60126 Ancona, Italy
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3
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Ali A, Flatt PR, Irwin N. Gut-Derived Peptide Hormone Analogues and Potential Treatment of Bone Disorders in Obesity and Diabetes Mellitus. Clin Med Insights Endocrinol Diabetes 2024; 17:11795514241238059. [PMID: 38486712 PMCID: PMC10938612 DOI: 10.1177/11795514241238059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 02/14/2024] [Indexed: 03/17/2024] Open
Abstract
Obesity and diabetes mellitus are prevalent metabolic disorders that have a detrimental impact on overall health. In this regard, there is now a clear link between these metabolic disorders and compromised bone health. Interestingly, both obesity and diabetes lead to elevated risk of bone fracture which is independent of effects on bone mineral density (BMD). In this regard, gastrointestinal (GIT)-derived peptide hormones and their related long-acting analogues, some of which are already clinically approved for diabetes and/or obesity, also seem to possess positive effects on bone remodelling and microarchitecture to reduce bone fracture risk. Specifically, the incretin peptides, glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), as well as glucagon-like peptide-2 (GLP-2), exert key direct and/or indirect benefits on bone metabolism. This review aims to provide an initial appraisal of the relationship between obesity, diabetes and bone, with a focus on the positive impact of these GIT-derived peptide hormones for bone health in obesity/diabetes. Brief discussion of related peptides such as parathyroid hormone, leptin, calcitonin and growth hormone is also included. Taken together, drugs engineered to promote GIP, GLP-1 and GLP-2 receptor signalling may have potential to offer therapeutic promise for improving bone health in obesity and diabetes.
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Affiliation(s)
- Asif Ali
- Diabetes Research Centre, Biomedical Sciences Research Institute, Ulster University, Coleraine, Northern Ireland, UK
| | - Peter R Flatt
- Diabetes Research Centre, Biomedical Sciences Research Institute, Ulster University, Coleraine, Northern Ireland, UK
| | - Nigel Irwin
- Diabetes Research Centre, Biomedical Sciences Research Institute, Ulster University, Coleraine, Northern Ireland, UK
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Nguyen TT, Loureiro ZY, Desai A, DeSouza T, Joyce S, Khair L, Samant A, Cirka H, Solivan-Rivera J, Ziegler R, Brehm M, Messina LM, Corvera S. A distinct class of hematopoietic stem cells develop from the human yellow bone marrow. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.29.555167. [PMID: 37693594 PMCID: PMC10491256 DOI: 10.1101/2023.08.29.555167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Aging and metabolic diseases are accompanied by systemic inflammation, but the mechanisms that induce this state are not known. We developed a human bone-marrow organoid system to explore mechanisms underlying metabolic-disease associated systemic inflammation. We find that a distinct type of hematopoietic stem cell (HSC) develops in the adipose-rich, yellow bone marrow, which is known to gradually replace the hematopoietic red marrow as we age and during metabolic disease. Unlike HSCs derived from the red bone marrow, HSCs derived from the yellow bone marrow have higher proliferation rates, increase myeloid differentiation, skew towards pro-inflammatory M1 macrophage differentiation, and express a distinct transcriptomic profile associated with responsiveness to wounding. Yellow marrow-derived HSCs express higher levels of the leptin receptor, which we find to be further increased in patients with type 2 diabetes. Our work demonstrates that the human long bone yellow marrow is a niche for a distinct class of HSCs which could underlie hematopoietic dysfunction during aging and metabolic disease processes suggesting a shared inflammaging mechanism.
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Wang J, Liu S, Zhao Y, Naqvi SSZH, Duan R. The association between serum adipokines levels with senile osteoporosis: a systematic review and meta-analysis. Front Endocrinol (Lausanne) 2023; 14:1193181. [PMID: 37576959 PMCID: PMC10415163 DOI: 10.3389/fendo.2023.1193181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 07/10/2023] [Indexed: 08/15/2023] Open
Abstract
Objective The clinical correlation between adipokines levels in the blood and the incidence of senile osteoporosis (SOP) has not been clearly studied. We conducted this meta-analysis to elucidate the relationship between three common adipokines levels (leptin, adiponectin, and chemerin) and the incidence of SOP. Methods We searched databases such as CNKI, CBM, VIP, Wanfang, PubMed, Web of Science, Embase, and the Cochrane Library to collect articles published since the establishment of the database until July 30, 2022. Results In total, 11 studies met the selection criteria. Our meta-analysis showed that serum leptin levels were significantly lower (mean difference [MD], -2.53, 95% CI: -3.96 to -1.10, I2 = 96%), chemerin levels were significantly higher (MD, 30.06, 95% CI: 16.71 to 43.40, I2 = 94%), and adiponectin levels were not significantly different (MD, -0.55, 95% CI: -2.26 to 1.17, P = 0.53, I2 = 98%) in SOP patients compared with healthy older individuals with normal bone mineral density (BMD). In addition, correlation analysis showed that leptin levels were positively correlated with lumbar bone mineral density (LBMD) (r = 0.36) and femoral bone mineral density (FBMD) (r = 0.38), chemerin levels were negatively correlated with LBMD (r = -0.55) and FBMD (r = -0.48), and there were significant positive correlations between leptin and adiponectin levels and body mass index (BMI) (r = 0.91 and 0.97). Conclusions The likelihood of having SOP was higher in older individuals with low levels of leptin and higher levels of chemerin. In addition, BMI was somewhat lower with low levels of leptin and adiponectin. Systematic review registration https://www.crd.york.ac.uk/prospero/, identifier CRD42022356469.
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Affiliation(s)
- Jiangna Wang
- Department of Biochemistry and Molecular Biology, Basic Medical College, Shanxi Medical University, Taiyuan, China
| | - Shiwei Liu
- Department of Endocrinology, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, China
| | - Yuxiang Zhao
- Department of Endocrinology, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, China
| | - Syed Shah Zaman Haider Naqvi
- Department of Endocrinology, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, China
| | - Ruixue Duan
- Department of Endocrinology, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, China
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Austin MJ, Kalampalika F, Cawthorn WP, Patel B. Turning the spotlight on bone marrow adipocytes in haematological malignancy and non-malignant conditions. Br J Haematol 2023; 201:605-619. [PMID: 37067783 PMCID: PMC10952811 DOI: 10.1111/bjh.18748] [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: 12/20/2022] [Revised: 02/28/2023] [Accepted: 03/01/2023] [Indexed: 04/18/2023]
Abstract
Whilst bone marrow adipocytes (BMAd) have long been appreciated by clinical haemato-pathologists, it is only relatively recently, in the face of emerging data, that the adipocytic niche has come under the watchful eye of biologists. There is now mounting evidence to suggest that BMAds are not just a simple structural entity of bone marrow microenvironments but a bona fide driver of physio- and pathophysiological processes relevant to multiple aspects of health and disease. Whilst the truly multifaceted nature of BMAds has only just begun to emerge, paradigms have shifted already for normal, malignant and non-malignant haemopoiesis incorporating a view of adipocyte regulation. Major efforts are ongoing, to delineate the routes by which BMAds participate in health and disease with a final aim of achieving clinical tractability. This review summarises the emerging role of BMAds across the spectrum of normal and pathological haematological conditions with a particular focus on its impact on cancer therapy.
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Affiliation(s)
- Michael J. Austin
- Barts Cancer Institute, Centre for Haemato‐OncologyQueen Mary University of LondonLondonUK
| | - Foteini Kalampalika
- Barts Cancer Institute, Centre for Haemato‐OncologyQueen Mary University of LondonLondonUK
| | - William P. Cawthorn
- BHF/University Centre for Cardiovascular Science, Edinburgh BioquarterUniversity of EdinburghEdinburghUK
| | - Bela Patel
- Barts Cancer Institute, Centre for Haemato‐OncologyQueen Mary University of LondonLondonUK
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Bojko J, Khoury M, Masson W, Weber A, Hilgers C, Bourauel C, Steinmetz M, Welle K, Schildberg FA, Kabir K. Impact of Long-term, High-fat, and High-cholesterol Diet on Murine Vertebrae Bones. ZEITSCHRIFT FUR ORTHOPADIE UND UNFALLCHIRURGIE 2021; 159:659-665. [PMID: 32702758 DOI: 10.1055/a-1194-5554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
As the percentage of overweight individuals in the population rises, diseases associated with excess weight resulting from poor nutrition are becoming more and more widespread. So far, the influence of weight or nutrition on bone health has shown conflicting results. In the literature, the existing studies disagree about the effect of diet on bones. Therefore, this study investigated the impact of a long-term, high-fat, and high-cholesterol diet on the spine in a mouse model. Wild-type mice were randomly separated into two groups; one group received a high-fat and high-cholesterol diet, and a control group was fed with a regular diet since birth for a duration of 8 months. The first to fifth thoracic vertebrae were extracted and investigated using histology and micro-CT. Samples were analyzed regarding different parameters: percentage of bone structure compared to the whole vertebra and the amount and thickness of the trabeculae. Both methods of the analysis showed similar results. Diet did not have a significant impact on the bone density of the vertebrae. The micro-CT examination showed that the average bone percentage of the examined vertebra was 6% (p = 0.2330) higher in the control group compared to the diet group. The same tendency was demonstrated in histology even though with a smaller difference of only 5%. The results of both methods were comparable and showed trends for the influence of different diets but not significant impacts. In summary, this study showed that a high-fat and high-cholesterol diet has a slightly negative impact on bone density. In order to further analyze the effects of different diets on bone composition, structure, and density, additional long-term studies should be carried out, and more parameters such as movement and genetic factors should be analyzed. Furthermore, other parameters such as exercise and genetic factors that could have a secondary influence on obesity should be investigated.
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Affiliation(s)
- Jessica Bojko
- Clinic for Orthopedics and Trauma Surgery, University Hospital Bonn
| | - Mona Khoury
- Clinic for Orthopedics and Trauma Surgery, University Hospital Bonn
| | - Werner Masson
- Clinic for Orthopedics and Trauma Surgery, University Hospital Bonn
| | - Anna Weber
- Oral Technology, School of Dentistry, University of Bonn
| | - Cäcilia Hilgers
- Clinic for Orthopedics and Trauma Surgery, University Hospital Bonn
| | | | - Martin Steinmetz
- Department of Cardiology, Heart Center Bonn, University Hospital Bonn
| | - Kristian Welle
- Clinic for Orthopedics and Trauma Surgery, University Hospital Bonn
| | | | - Koroush Kabir
- Clinic for Orthopedics and Trauma Surgery, University Hospital Bonn
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Freire EBL, d’Alva CB, Madeira MP, Lima GEDCP, Montenegro APDR, Fernandes VO, Montenegro Junior RM. Bone Mineral Density in Congenital Generalized Lipodystrophy: The Role of Bone Marrow Tissue, Adipokines, and Insulin Resistance. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18189724. [PMID: 34574647 PMCID: PMC8465110 DOI: 10.3390/ijerph18189724] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/05/2021] [Accepted: 07/16/2021] [Indexed: 12/31/2022]
Abstract
Congenital Generalized Lipodystrophy (CGL) is a rare syndrome characterized by the almost total absence of subcutaneous adipose tissue due to the inability of storing lipid in adipocytes. Patients present generalized lack of subcutaneous fat and normal to low weight. They evolve with severe metabolic disorders, non-alcoholic fatty liver disease, early cardiac abnormalities, and infectious complications. Although low body weight is a known risk factor for osteoporosis, it has been reported that type 1 and 2 CGL have a tendency of high bone mineral density (BMD). In this review, we discuss the role of bone marrow tissue, adipokines, and insulin resistance in the setting of the normal to high BMD of CGL patients. Data bases from Pubmed and LILACS were searched, and 113 articles published until 10 April 2021 were obtained. Of these, 76 were excluded for not covering the review topic. A manual search for additional literature was performed using the bibliographies of the studies located. The elucidation of the mechanisms responsible for the increase in BMD in this unique model of insulin resistance may contribute to the understanding of the interrelationships between bone, muscle, and adipose tissue in a pathophysiological and therapeutic perspective.
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9
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Endocrine role of bone in the regulation of energy metabolism. Bone Res 2021; 9:25. [PMID: 34016950 PMCID: PMC8137703 DOI: 10.1038/s41413-021-00142-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 12/20/2020] [Accepted: 01/12/2021] [Indexed: 02/06/2023] Open
Abstract
Bone mainly functions as a supportive framework for the whole body and is the major regulator of calcium homeostasis and hematopoietic function. Recently, an increasing number of studies have characterized the significance of bone as an endocrine organ, suggesting that bone-derived factors regulate local bone metabolism and metabolic functions. In addition, these factors can regulate global energy homeostasis by altering insulin sensitivity, feeding behavior, and adipocyte commitment. These findings may provide a new pathological mechanism for related metabolic diseases or be used in the diagnosis, treatment, and prevention of metabolic diseases such as osteoporosis, obesity, and diabetes mellitus. In this review, we summarize the regulatory effect of bone and bone-derived factors on energy metabolism and discuss directions for future research.
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Piotrowska K, Tarnowski M. Bone Marrow Adipocytes-Role in Physiology and Various Nutritional Conditions in Human and Animal Models. Nutrients 2021; 13:nu13051412. [PMID: 33922353 PMCID: PMC8146898 DOI: 10.3390/nu13051412] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 04/19/2021] [Accepted: 04/20/2021] [Indexed: 02/06/2023] Open
Abstract
In recent years, adipose tissue has attracted a lot of attention. It is not only an energy reservoir but also plays important immune, paracrine and endocrine roles. BMAT (bone marrow adipose tissue) is a heterogeneous tissue, found mostly in the medullary canal of the long bones (tibia, femur and humerus), in the vertebrae and iliac crest. Adipogenesis in bone marrow cavities is a consequence of ageing or may accompany pathologies like diabetes mellitus type 1 (T1DM), T2DM, anorexia nervosa, oestrogen and growth hormone deficiencies or impaired haematopoiesis and osteoporosis. This paper focuses on studies concerning BMAT and its physiology in dietary interventions, like obesity in humans and high fat diet in rodent studies; and opposite: anorexia nervosa and calorie restriction in animal models.
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Trinh T, Broxmeyer HE. Role for Leptin and Leptin Receptors in Stem Cells During Health and Diseases. Stem Cell Rev Rep 2021; 17:511-522. [PMID: 33598894 PMCID: PMC7889057 DOI: 10.1007/s12015-021-10132-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/31/2021] [Indexed: 12/14/2022]
Abstract
Hematopoietic stem cells (HSCs) give rise to all blood and immune cells in the body. These rare cells reside in the hypoxic niche of the bone marrow (BM) where they are subjected to a complex network of regulatory factors including cellular and molecular components. To sustain hematopoiesis over the lifetime of an individual, HSCs maintain distinctive metabolic programs, and in recent years nutritional factors have been increasingly recognized as critical regulators of HSC numbers and functions. Leptin (LEP), a neuroendocrine messenger, and its receptor (LEPR) are well-known for their immunomodulatory and energy balancing effects; yet, how LEP/LEPR signaling plays a role in hematopoiesis is under-appreciated. In this review, we summarize and highlight recent work that demonstrated involvement of LEP/LEPR in hematopoiesis under steady state or stress-associated situations as well as in pathological conditions such as cardiovascular diseases and malignancies. Although the field is only in its infancy, these studies suggest evidence of potential clinical applications and proof-of-principle for more in-depth future research.
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Affiliation(s)
- Thao Trinh
- Departments of Microbiology/Immunology, Indiana University School of Medicine, 950 West Walnut Street, Bldg. R2, Room 302, Indianapolis, IN, 46202-5121, USA
| | - Hal E Broxmeyer
- Departments of Microbiology/Immunology, Indiana University School of Medicine, 950 West Walnut Street, Bldg. R2, Room 302, Indianapolis, IN, 46202-5121, USA.
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Bagias C, Sukumar N, Weldeselassie Y, Oyebode O, Saravanan P. Cord Blood Adipocytokines and Body Composition in Early Childhood: A Systematic Review and Meta-Analysis. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18041897. [PMID: 33669328 PMCID: PMC7920289 DOI: 10.3390/ijerph18041897] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 02/07/2021] [Accepted: 02/12/2021] [Indexed: 01/02/2023]
Abstract
Childhood obesity is a growing epidemic. Early identification of high-risk groups will allow for the development of prevention strategies. Cord blood adipocytokines have been previously examined as biomarkers predicting future obesity. We conducted a systematic review looking at the association between cord blood leptin and adiponectin with adiposity up to 5 years of age. A literature review was performed between January 1994 and August 2020 using two bibliographic databases (Medline/Pubmed and EMBASE) and was registered on PROSPERO (CRD42017069024). Studies using skinfold thickness and direct methods of assessing body composition in full term neonates were considered. Partial correlation and multiple regression models were used to present the results. Meta-analysis was performed, were possible, using a random effects model. Cochran’s Q test was used to assess heterogeneity and I2 statistics to calculate the percentage of variation across studies. The potential for publication bias was assessed using funnel plots. Data from 22 studies were retrieved and reviewed by two independent reviewers. Cord blood leptin was positively associated with adiposity at birth (r = 0.487; 95% CI: 0.444, 0.531) but was inversely related to adiposity up to 3 years of age. The association was not sustained at 5 years. There was a weak positive association between adiponectin in cord blood and adiposity at birth (r = 0.201; 95% CI: 0.125, 0.277). No correlation was found between cord blood adiponectin in young children, but data were limited. This review supports that cord blood leptin and adiponectin are associated with adiposity at birth. The results of this study provide insight into the role of adipocytokines at birth on future metabolic health and their potential use as risk stratification tools.
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Affiliation(s)
- Christos Bagias
- Division of Health Sciences, Department of Population Evidence and Technologies, Warwick Medical School, University of Warwick, Coventry CV7 7HL, UK; (C.B.); (N.S.); (Y.W.); (O.O.)
- Department of Endocrinology and Diabetes, University Hospital of Ioannina, 45500 Ioannina, Greece
| | - Nithya Sukumar
- Division of Health Sciences, Department of Population Evidence and Technologies, Warwick Medical School, University of Warwick, Coventry CV7 7HL, UK; (C.B.); (N.S.); (Y.W.); (O.O.)
- Academic Department of Diabetes, Endocrinology and Metabolism, George Eliot Hospital NHS Trust, Nuneaton CV10 7DJ, UK
| | - Yonas Weldeselassie
- Division of Health Sciences, Department of Population Evidence and Technologies, Warwick Medical School, University of Warwick, Coventry CV7 7HL, UK; (C.B.); (N.S.); (Y.W.); (O.O.)
| | - Oyinlola Oyebode
- Division of Health Sciences, Department of Population Evidence and Technologies, Warwick Medical School, University of Warwick, Coventry CV7 7HL, UK; (C.B.); (N.S.); (Y.W.); (O.O.)
| | - Ponnusamy Saravanan
- Division of Health Sciences, Department of Population Evidence and Technologies, Warwick Medical School, University of Warwick, Coventry CV7 7HL, UK; (C.B.); (N.S.); (Y.W.); (O.O.)
- Academic Department of Diabetes, Endocrinology and Metabolism, George Eliot Hospital NHS Trust, Nuneaton CV10 7DJ, UK
- Correspondence:
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13
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Zinngrebe J, Debatin KM, Fischer-Posovszky P. Adipocytes in hematopoiesis and acute leukemia: friends, enemies, or innocent bystanders? Leukemia 2020; 34:2305-2316. [PMID: 32474572 PMCID: PMC7449871 DOI: 10.1038/s41375-020-0886-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 05/15/2020] [Accepted: 05/21/2020] [Indexed: 02/07/2023]
Abstract
The bone marrow is home to well-balanced normal hematopoiesis, but also the stage of leukemia's crime. Marrow adipose tissue (MAT) is a unique and versatile component of the bone marrow niche. While the importance of MAT for bone health has long been recognized, its complex role in hematopoiesis has only recently gained attention. In this review article we summarize recent conceptual advances in the field of MAT research and how these developments impact our understanding of MAT regulation of hematopoiesis. Elucidating routes of interaction and regulation between MAT and cells of the hematopoietic system are essential to pinpoint vulnerable processes resulting in malignant transformation. The concept of white adipose tissue contributing to cancer development and progression on the cellular, metabolic, and systemic level is generally accepted. The role of MAT in malignant hematopoiesis, however, is controversial. MAT is very sensitive to changes in the patient's metabolic status hampering a clear definition of its role in different clinical situations. Here, we discuss future directions for leukemia research in the context of metabolism-induced modifications of MAT and other adipose tissues and how this might impact on leukemia cell survival, proliferation, and antileukemic therapy.
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Affiliation(s)
- Julia Zinngrebe
- Department of Pediatrics and Adolescent Medicine, Ulm University Medical Centre, D-89075, Ulm, Germany
| | - Klaus-Michael Debatin
- Department of Pediatrics and Adolescent Medicine, Ulm University Medical Centre, D-89075, Ulm, Germany
| | - Pamela Fischer-Posovszky
- Department of Pediatrics and Adolescent Medicine, Ulm University Medical Centre, D-89075, Ulm, Germany.
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14
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Wang H, Lu CH, Ho PC. Metabolic adaptation orchestrates tissue context-dependent behavior in regulatory T cells. Immunol Rev 2020; 295:126-139. [PMID: 32147869 DOI: 10.1111/imr.12844] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 02/19/2020] [Indexed: 02/07/2023]
Abstract
The diverse distribution and functions of regulatory T cells (Tregs) ensure tissue and immune homeostasis; however, it remains unclear which factors can guide distribution, local differentiation, and tissue context-specific behavior in Tregs. Although the emerging concept that Tregs could re-adjust their transcriptome based on their habitations is supported by recent findings, the underlying mechanisms that reprogram transcriptome in Tregs are unknown. In the past decade, metabolic machineries have been revealed as a new regulatory circuit, known as immunometabolic regulation, to orchestrate activation, differentiation, and functions in a variety of immune cells, including Tregs. Given that systemic and local alterations of nutrient availability and metabolite profile associate with perturbation of Treg abundance and functions, it highlights that immunometabolic regulation may be one of the mechanisms that orchestrate tissue context-specific regulation in Tregs. The understanding on how metabolic program instructs Tregs in peripheral tissues not only represents a critical opportunity to delineate a new avenue in Treg biology but also provides a unique window to harness Treg-targeting approaches for treating cancer and autoimmunity with minimizing side effects. This review will highlight the metabolic features on guiding Treg formation and function in a disease-oriented perspective and aim to pave the foundation for future studies.
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Affiliation(s)
- Haiping Wang
- Department of Fundamental Oncology, University of Lausanne, Lausanne, Switzerland.,Ludwig Institute for Cancer Research, University of Lausanne, Epalinges, Switzerland
| | - Chun-Hao Lu
- Department of Fundamental Oncology, University of Lausanne, Lausanne, Switzerland.,Ludwig Institute for Cancer Research, University of Lausanne, Epalinges, Switzerland
| | - Ping-Chih Ho
- Department of Fundamental Oncology, University of Lausanne, Lausanne, Switzerland.,Ludwig Institute for Cancer Research, University of Lausanne, Epalinges, Switzerland
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15
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Li J, Chen X, Lu L, Yu X. The relationship between bone marrow adipose tissue and bone metabolism in postmenopausal osteoporosis. Cytokine Growth Factor Rev 2020; 52:88-98. [PMID: 32081538 DOI: 10.1016/j.cytogfr.2020.02.003] [Citation(s) in RCA: 76] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2019] [Revised: 02/06/2020] [Accepted: 02/06/2020] [Indexed: 02/06/2023]
Abstract
Postmenopausal osteoporosis (PMOP) is a prevalent skeletal disorder associated with menopause-related estrogen withdrawal. PMOP is characterized by low bone mass, deterioration of the skeletal microarchitecture, and subsequent increased susceptibility to fragility fractures, thus contributing to disability and mortality. Accumulating evidence indicates that abnormal expansion of marrow adipose tissue (MAT) plays a crucial role in the onset and progression of PMOP, in part because both bone marrow adipocytes and osteoblasts share a common ancestor lineage. The cohabitation of MAT adipocytes, mesenchymal stromal cells, hematopoietic cells, osteoblasts and osteoclasts in the bone marrow creates a microenvironment that permits adipocytes to act directly on other cell types in the marrow. Furthermore, MAT, which is recognized as an endocrine organ, regulates bone remodeling through the secretion of adipokines and cytokines. Although an enhanced MAT volume is linked to low bone mass and fractures in PMOP, the detailed interactions between MAT and bone metabolism remain largely unknown. In this review, we examine the possible mechanisms of MAT expansion under estrogen withdrawal and further summarize emerging findings regarding the pathological roles of MAT in bone remodeling. We also discuss the current therapies targeting MAT in osteoporosis. A comprehensive understanding of the relationship between MAT expansion and bone metabolism in estrogen deficiency conditions will provide new insights into potential therapeutic targets for PMOP.
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Affiliation(s)
- Jiao Li
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology and Metabolism, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Xiang Chen
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology and Metabolism, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Lingyun Lu
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology and Metabolism, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, China; Department of Integrated Traditional Chinese and Western Medicine, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China
| | - Xijie Yu
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology and Metabolism, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, China.
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16
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Bravenboer N, Bredella MA, Chauveau C, Corsi A, Douni E, Ferris WF, Riminucci M, Robey PG, Rojas-Sutterlin S, Rosen C, Schulz TJ, Cawthorn WP. Standardised Nomenclature, Abbreviations, and Units for the Study of Bone Marrow Adiposity: Report of the Nomenclature Working Group of the International Bone Marrow Adiposity Society. Front Endocrinol (Lausanne) 2020; 10:923. [PMID: 32038486 PMCID: PMC6993042 DOI: 10.3389/fendo.2019.00923] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Accepted: 12/18/2019] [Indexed: 12/16/2022] Open
Abstract
Research into bone marrow adiposity (BMA) has expanded greatly since the late 1990s, leading to development of new methods for the study of bone marrow adipocytes. Simultaneously, research fields interested in BMA have diversified substantially. This increasing interest is revealing fundamental new knowledge of BMA; however, it has also led to a highly variable nomenclature that makes it difficult to interpret and compare results from different studies. A consensus on BMA nomenclature has therefore become indispensable. This article addresses this critical need for standardised terminology and consistent reporting of parameters related to BMA research. The International Bone Marrow Adiposity Society (BMAS) was formed in 2017 to consolidate the growing scientific community interested in BMA. To address the BMA nomenclature challenge, BMAS members from diverse fields established a working group (WG). Based on their broad expertise, the WG first reviewed the existing, unsystematic nomenclature and identified terms, and concepts requiring further discussion. They thereby identified and defined 8 broad concepts and methods central to BMA research. Notably, these had been described using 519 unique combinations of term, abbreviation and unit, many of which were overlapping or redundant. On this foundation a second consensus was reached, with each term classified as "to use" or "not to use." As a result, the WG reached a consensus to craft recommendations for 26 terms related to concepts and methods in BMA research. This was approved by the Scientific Board and Executive Board of BMAS and is the basis for the present recommendations for a formal BMA nomenclature. As an example, several terms or abbreviations have been used to represent "bone marrow adipocytes," including BMAds, BM-As, and BMAs. The WG decided that BMA should refer to "bone marrow adiposity"; that BM-A is too similar to BMA; and noted that "Ad" has previously been recommended to refer to adipocytes. Thus, it was recommended to use BMAds to represent bone marrow adipocytes. In conclusion, the standard nomenclature proposed in this article should be followed for all communications of results related to BMA. This will allow for better interactions both inside and outside of this emerging scientific community.
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Affiliation(s)
- Nathalie Bravenboer
- Department of Clinical Chemistry, Amsterdam Movement Sciences, Amsterdam University Medical Center, Vrije Universiteit, Amsterdam, Netherlands
| | - Miriam A. Bredella
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States
| | - Christophe Chauveau
- Univ. Littoral Côte d'Opale, Boulogne-sur-Mer, France
- Univ. Lille, Lille, France
- CHU Lille, Lille, France
- Physiopathologie des Maladies Osseuses Inflammatoires, Boulogne-sur-Mer, France
| | - Alessandro Corsi
- Department of Molecular Medicine, Sapienza University of Rome, Rome, Italy
| | - Eleni Douni
- Biological Sciences Research Center “Alexander Fleming”, Athens, Greece
- Department of Biotechnology, Agricultural University of Athens, Athens, Greece
| | - William F. Ferris
- Division of Endocrinology, Department of Medicine, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Mara Riminucci
- Department of Molecular Medicine, Sapienza University of Rome, Rome, Italy
| | - Pamela G. Robey
- Skeletal Biology Section, NIDCR, NIH, DHHS, Bethesda, MD, United States
| | - Shanti Rojas-Sutterlin
- Institute for Research in Immunology and Cancer, Université de Montréal, Montreal, QC, Canada
| | - Clifford Rosen
- Maine Medical Research Center Institute, Scarborough, ME, United States
| | - Tim J. Schulz
- German Institute of Human Nutrition Potsdam-Rehbrücke, Nuthetal, Germany
- German Center for Diabetes Research (DZD), München, Germany
| | - William P. Cawthorn
- BHF Centre for Cardiovascular Science, The Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
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17
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Gioldasi S, Karvela A, Rojas-Gil AP, Rodi M, de Lastic AL, Thomas I, Spiliotis BE, Mouzaki A. Metabolic Association between Leptin and the Corticotropin Releasing Hormone. Endocr Metab Immune Disord Drug Targets 2020; 19:458-466. [PMID: 30727936 PMCID: PMC7360915 DOI: 10.2174/1871530319666190206165626] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 10/31/2018] [Accepted: 12/27/2018] [Indexed: 01/29/2023]
Abstract
Objective In healthy individuals, leptin is produced from adipose tissue and is secreted into the circulation to communicate energy balance status to the brain and control fat metabolism. Corticotropin-Releasing Hormone (CRH) is synthesized in the hypothalamus and regulates stress responses. Among the many adipokines and hormones that control fat metabolism, leptin and CRH both curb appetite and inhibit food intake. Despite numerous reports on leptin and CRH properties and function, little has been actually shown about their association in the adipose tissue environment. Methods In this article, we summarized the salient information on leptin and CRH in relation to metabolism. We also investigated the direct effect of recombinant CRH on leptin secretion by primary cultures of human adipocytes isolated from subcutaneous abdominal adipose tissue of 7 healthy children and adolescents, and measured CRH and leptin levels in plasma collected from peripheral blood of 24 healthy children and adolescents to assess whether a correlation exists between CRH and leptin levels in the periphery. Results and Conclusion The available data indicate that CRH exerts a role in the regulation of leptin in human adipocytes. We show that CRH downregulates leptin production by mature adipocytes and that a strong negative correlation exists between CRH and leptin levels in the periphery, and suggest the possible mechanisms of CRH control of leptin. Delineation of CRH control of leptin production by adipocytes may explain unknown pathogenic mechanisms linking stress and metabolism.
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Affiliation(s)
- Sofia Gioldasi
- Division of Hematology, Department of Internal Medicine, Medical School, University of Patras, Patras, Greece
| | - Alexia Karvela
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics, Medical School, University of Patras, Patras, Greece
| | | | - Maria Rodi
- Division of Hematology, Department of Internal Medicine, Medical School, University of Patras, Patras, Greece
| | - Anne-Lise de Lastic
- Division of Hematology, Department of Internal Medicine, Medical School, University of Patras, Patras, Greece
| | - Iason Thomas
- Department of Allergy, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Bessie E Spiliotis
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics, Medical School, University of Patras, Patras, Greece
| | - Athanasia Mouzaki
- Division of Hematology, Department of Internal Medicine, Medical School, University of Patras, Patras, Greece
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18
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Abstract
PURPOSE OF REVIEW The age-related accumulation of bone marrow adipose tissue (BMAT) negatively impacts bone metabolism and hematopoiesis. This review provides an overview about BMAT-secreted factors as biomarkers for BMAT accumulation and osteoporosis risk. RECENT FINDINGS The adipokines leptin and adiponectin are regulators of BMAT. It remains to be clarified if locally produced adipokines substantially contribute to their peripheral serum levels and if they influence bone metabolism beyond that of extraosseous adipokine production. Existing data also suggests that BMAT disturbs bone metabolism primarily through palmitate-mediated toxic effects on osteoblasts and osteocytes, including dysregulated autophagy and apoptosis. BMAT-secreted factors are important modulators of bone metabolism. However, the majority of our understanding about MAT-secreted factors and their paracrine and endocrine effects is derived from in vitro studies and animal experiments. Therefore, more research is needed before BMAT-secreted biomarkers can be applied in medical practice.
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Affiliation(s)
- Markus Herrmann
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Auenbruggerplatz 15/1, 8036, Graz, Austria.
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19
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Abstract
The skeleton harbors an array of lineage cells that have an essential role in whole body homeostasis. Adipocytes start the colonization of marrow space early in postnatal life, expanding progressively and influencing other components of the bone marrow through paracrine signaling. In this unique, closed, and hypoxic environment close to the endosteal surface and adjacent to the microvascular space the marrow adipocyte can store or provide energy, secrete adipokines, and target neighboring bone cells. Adipocyte progenitors can also migrate from the bone marrow to populate white adipose tissue, a process that accelerates during weight gain. The marrow adipocyte also has an endocrine role in whole body homeostasis through its varied secretome that targets distant adipose depots, skeletal muscle, and the nervous system. Further insights into the biology of this unique and versatile cell will undoubtedly lead to novel therapeutic approaches to metabolic and age-related disorders such as osteoporosis and diabetes mellitus.
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Affiliation(s)
- Francisco J A de Paula
- Department of Internal Medicine, Ribeirao Preto Medical School, University of São Paulo, São Paulo 14049-900, Brazil;
| | - Clifford J Rosen
- Center for Clinical and Translational Research, Maine Medical Center Research Institute, Scarborough, Maine 04074, USA;
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20
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Miggitsch C, Meryk A, Naismith E, Pangrazzi L, Ejaz A, Jenewein B, Wagner S, Nägele F, Fenkart G, Trieb K, Zwerschke W, Grubeck-Loebenstein B. Human bone marrow adipocytes display distinct immune regulatory properties. EBioMedicine 2019; 46:387-398. [PMID: 31327694 PMCID: PMC6711052 DOI: 10.1016/j.ebiom.2019.07.023] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 07/02/2019] [Accepted: 07/08/2019] [Indexed: 01/14/2023] Open
Abstract
Background The bone marrow (BM) is a major reservoir of resting memory T cells and long-lived plasma cells, capable of providing protection against recurrent infections. Whether the age-related accumulation of adipose tissue in the BM affects the functionality and maintenance of memory cells is not well understood. Methods For the first time, we compare human femur marrow adipose tissue (fMAT) and subcutaneous white adipose tissue of the thigh (tsWAT) obtained from the same donors. Therefore, we used microarrays for comparative global gene expression analysis, and employed assays to analyse parameters of adipocyte biology, inflammation and oxidative stress. Findings We show that fMAT adipocytes differ significantly from tsWAT adipocytes regarding specific gene expression profiles including inflammatory responses and adipogenesis/adipocyte phenotype. Concomitant with considerably lower levels of CD36, a membrane-associated protein important for long-chain fatty acid uptake that is used as maturation marker, fMAT adipocytes are smaller and contain less triglycerides. fMAT adipocytes secrete similar levels of adiponectin and leptin as tsWAT adipocytes, and express increased levels of pro-inflammatory molecules concomitant with an elevated generation of reactive oxygen species (ROS) and impaired function of plasma cells in the BM. Interpretation Our findings suggest that fMAT is a unique type of adipose tissue containing small adipocytes with lower CD36 protein and triglyceride levels than tsWAT but high adipokine secretion. Moreover, fMAT adipocytes secrete high levels of pro-inflammatory cytokines, contributing to inflammation and impairment of plasma cell function in the BM, suggesting that fMAT has more immune regulatory functions than tsWAT.
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Affiliation(s)
- Carina Miggitsch
- Department of Immunology, Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, Innsbruck, Tyrol 6020, Austria
| | - Andreas Meryk
- Department of Immunology, Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, Innsbruck, Tyrol 6020, Austria.
| | - Erin Naismith
- Department of Immunology, Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, Innsbruck, Tyrol 6020, Austria
| | - Luca Pangrazzi
- Department of Immunology, Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, Innsbruck, Tyrol 6020, Austria
| | - Asim Ejaz
- Division of Cell Metabolism and Differentiation Research, Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, Innsbruck, Tyrol 6020, Austria; Department of Plastic Surgery, University of Pittsburgh, 3550 Terrace Street 6B Scaife Hall, Pittsburgh, PA 15261, United States
| | - Brigitte Jenewein
- Department of Immunology, Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, Innsbruck, Tyrol 6020, Austria
| | - Sonja Wagner
- Department of Immunology, Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, Innsbruck, Tyrol 6020, Austria; Division of Cell Metabolism and Differentiation Research, Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, Innsbruck, Tyrol 6020, Austria
| | - Fabiana Nägele
- Department of Immunology, Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, Innsbruck, Tyrol 6020, Austria
| | - Gabriella Fenkart
- Department of Immunology, Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, Innsbruck, Tyrol 6020, Austria; Department for Genomics, Stem Cell Biology and Regenerative Medicine, Institute of Molecular Biology, University of Innsbruck, Technikerstraße 25, Innsbruck, Tyrol 6020, Austria
| | - Klemens Trieb
- Department of Orthopedic Surgery, Klinikum Wels, Grieskirchner Str. 42, Wels, Upper Austria 4600, Austria; Computed Tomography Research Group, University of Applied Sciences Upper Austria, Stelzhamerstr. 23, 4600 Wels, Austria
| | - Werner Zwerschke
- Division of Cell Metabolism and Differentiation Research, Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, Innsbruck, Tyrol 6020, Austria
| | - Beatrix Grubeck-Loebenstein
- Department of Immunology, Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, Innsbruck, Tyrol 6020, Austria
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21
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Bone Marrow Adipocytes: The Enigmatic Components of the Hematopoietic Stem Cell Niche. J Clin Med 2019; 8:jcm8050707. [PMID: 31109063 PMCID: PMC6572059 DOI: 10.3390/jcm8050707] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 05/09/2019] [Accepted: 05/16/2019] [Indexed: 12/24/2022] Open
Abstract
Bone marrow adipocytes (BMA) exert pleiotropic roles beyond mere lipid storage and filling of bone marrow (BM) empty spaces, and we are only now beginning to understand their regulatory traits and versatility. BMA arise from the differentiation of BM mesenchymal stromal cells, but they seem to be a heterogeneous population with distinct metabolisms, lipid compositions, secretory properties and functional responses, depending on their location in the BM. BMA also show remarkable differences among species and between genders, they progressively replace the hematopoietic BM throughout aging, and play roles in a range of pathological conditions such as obesity, diabetes and anorexia. They are a crucial component of the BM microenvironment that regulates hematopoiesis, through mechanisms largely unknown. Previously considered as negative regulators of hematopoietic stem cell function, recent data demonstrate their positive support for hematopoietic stem cells depending on the experimental approach. Here, we further discuss current knowledge on the role of BMA in hematological malignancies. Early hints suggest that BMA may provide a suitable metabolic niche for the malignant growth of leukemic stem cells, and protect them from chemotherapy. Future in vivo functional work and improved isolation methods will enable determining the true essence of this elusive BM hematopoietic stem cell niche component, and confirm their roles in a range of diseases. This promising field may open new pathways for efficient therapeutic strategies to restore hematopoiesis, targeting BMA.
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22
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Yang Y, Dong F, Liu X, Xu J, Wu X, Wang D, Zheng Y. Developmental toxicity by thifluzamide in zebrafish (Danio rerio): Involvement of leptin. CHEMOSPHERE 2019; 221:863-869. [PMID: 30703632 DOI: 10.1016/j.chemosphere.2019.01.043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2018] [Revised: 01/03/2019] [Accepted: 01/06/2019] [Indexed: 06/09/2023]
Abstract
Although previous trials have indicated that thifluzamide induces developmental inhibition in zebrafish, understanding the distinct mechanism of thifluzamide in this process remains challenging. This study investigated the effect of thifluzamide on zebrafish development and the underlying related signaling pathway. Thifluzamide repressed glucagon (GC) levels but increased growth hormone (GH) levels, and changed the expression of the genes related to growth and development. Additionally, protein kinase A (PKA) and leptin levels were obviously decreased in zebrafish after exposure to thifluzamide for 28 days, but the phosphorylation of cAMP responsive element-binding protein (CREB) was increased. Our results suggested that the anti-developmental effects of thifluzamide in zebrafish are largely associated with alterations in expressions of genes related to growth and development through modulation of leptin.
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Affiliation(s)
- Yang Yang
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, People's Republic of China
| | - Fengshou Dong
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, People's Republic of China
| | - Xingang Liu
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, People's Republic of China
| | - Jun Xu
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, People's Republic of China
| | - Xiaohu Wu
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, People's Republic of China
| | - Donghui Wang
- Plant Developmental Biology, College of Life Sciences, Peking University, 5 Yiheyuan Road, Beijing 100871, China
| | - Yongquan Zheng
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, People's Republic of China.
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23
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Li Y, Meng Y, Yu X. The Unique Metabolic Characteristics of Bone Marrow Adipose Tissue. Front Endocrinol (Lausanne) 2019; 10:69. [PMID: 30800100 PMCID: PMC6375842 DOI: 10.3389/fendo.2019.00069] [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: 06/15/2018] [Accepted: 01/24/2019] [Indexed: 02/05/2023] Open
Abstract
Bone marrow adipose tissue (MAT) is distinct from white adipose tissue (WAT) or brown adipose tissue (BAT) for its location, feature and function. As a largely ignored adipose depot, it is situated in bone marrow space and resided with bone tissue side-by-side. MAT is considered not only as a regulator of bone metabolism through paracrine, but also as a functionally particular adipose tissue that may contribute to global metabolism. Adipokines, inflammatory factors and other molecules derived from bone marrow adipocytes may exert systematic effects. In this review, we summary the evidence from several aspects including development, distribution, histological features and phenotype to elaborate the basic characteristics of MAT. We discuss the association between bone metabolism and MAT, and highlight our current understanding of this special adipose tissue. We further demonstrate the probable relationship between MAT and energy metabolism, as well as glucose metabolism. On the basis of preliminary results from animal model and clinical studies, we propose that MAT has its unique secretory and metabolic function, although there is no in-depth study at present.
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Affiliation(s)
- Yujue Li
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology and Metabolism and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
| | - Yang Meng
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology and Metabolism and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
- Department of Orthopedics, West China Hospital, Sichuan University, Chengdu, China
| | - Xijie Yu
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology and Metabolism and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
- *Correspondence: Xijie Yu ;
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24
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Fornetti J, Welm AL, Stewart SA. Understanding the Bone in Cancer Metastasis. J Bone Miner Res 2018; 33:2099-2113. [PMID: 30476357 DOI: 10.1002/jbmr.3618] [Citation(s) in RCA: 246] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 10/17/2018] [Accepted: 10/18/2018] [Indexed: 12/11/2022]
Abstract
The bone is the third most common site of metastasis for a wide range of solid tumors including lung, breast, prostate, colorectal, thyroid, gynecologic, and melanoma, with 70% of metastatic prostate and breast cancer patients harboring bone metastasis.1 Unfortunately, once cancer spreads to the bone, it is rarely cured and is associated with a wide range of morbidities including pain, increased risk of fracture, and hypercalcemia. This fact has driven experts in the fields of bone and cancer biology to study the bone, and has revealed that there is a great deal that each can teach the other. The complexity of the bone was first described in 1889 when Stephen Paget proposed that tumor cells have a proclivity for certain organs, where they "seed" into a friendly "soil" and eventually grow into metastatic lesions. Dr. Paget went on to argue that although many study the "seed" it would be paramount to understand the "soil." Since this original work, significant advances have been made not only in understanding the cell-autonomous mechanisms that drive metastasis, but also alterations which drive changes to the "soil" that allow a tumor cell to thrive. Indeed, it is now clear that the "soil" in different metastatic sites is unique, and thus the mechanisms that allow tumor cells to remain in a dormant or growing state are specific to the organ in question. In the bone, our knowledge of the components that contribute to this fertile "soil" continues to expand, but our understanding of how they impact tumor growth in the bone remains in its infancy. Indeed, we now appreciate that the endosteal niche likely contributes to tumor cell dormancy, and that osteoclasts, osteocytes, and adipocytes can impact tumor cell growth. Here, we discuss the bone microenvironment and how it impacts cancer cell seeding, dormancy, and growth. © 2018 American Society for Bone and Mineral Research.
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Affiliation(s)
- Jaime Fornetti
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT, USA
| | - Alana L Welm
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT, USA
| | - Sheila A Stewart
- Departments of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA.,Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO, USA.,Integrating Communication within the Cancer Environment (ICCE) Institute, Washington University School of Medicine, St. Louis, MO, USA
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25
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Reid IR, Baldock PA, Cornish J. Effects of Leptin on the Skeleton. Endocr Rev 2018; 39:938-959. [PMID: 30184053 DOI: 10.1210/er.2017-00226] [Citation(s) in RCA: 102] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 06/26/2018] [Indexed: 12/12/2022]
Abstract
Leptin originates in adipocytes, including those in bone marrow, and circulates in concentrations 20 to 90 times higher than those in the cerebrospinal fluid. It has direct anabolic effects on osteoblasts and chondrocytes, but it also influences bone indirectly, via the hypothalamus and sympathetic nervous system, via changes in body weight, and via effects on the production of other hormones (e.g., pituitary). Leptin's role in bone physiology is determined by the balance of these conflicting effects. Reflecting this inconsistency, the leptin-deficient mouse has reduced length and bone mineral content of long bones but increased vertebral trabecular bone. A consistent bone phenotype in human leptin deficiency has not been established. Systemic leptin administration in animals and humans usually exerts a positive effect on bone mass, and leptin administration into the cerebral ventricles usually normalizes the bone phenotype in leptin-deficient mice. Reflecting the role of the sympathetic nervous system in mediating the central catabolic effects of leptin on the skeleton, β-adrenergic agonists and antagonists have major effects on bone in mice, but this is not consistently seen in humans. The balance of the central and peripheral effects of leptin on bone remains an area of substantial controversy and might vary between species and according to other factors such as body weight, baseline circulating leptin levels, and the presence of specific pathologies. In humans, leptin is likely to contribute to the positive relationship observed between adiposity and bone density, which allows the skeleton to respond appropriately to changes in soft tissue mass.
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Affiliation(s)
- Ian R Reid
- University of Auckland, Auckland, New Zealand.,Department of Endocrinology, Auckland District Health Board, Auckland, New Zealand
| | - Paul A Baldock
- Garvan Institute of Medical Research, Sydney, New South Wales, Australia
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Effect of Leptin on Marrow Adiposity in Ovariectomized Rabbits Assessed by Proton Magnetic Resonance Spectroscopy. J Comput Assist Tomogr 2018; 42:588-593. [PMID: 29489596 DOI: 10.1097/rct.0000000000000725] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Leptin acts to influence bone metabolism through indirect hypothalamic relay and direct peripheral pathways. Leptin enhances the differentiation of mesenchymal stem cells to the osteoblast rather than the adipocyte lineage, but the in vivo impacts of leptin on ovariectomy (OVX)-induced marrow adiposity are poorly understood. In this work, we aimed to address this question. METHODS Forty-five female New Zealand rabbits were divided into sham + vehicle, OVX + vehicle, and OVX + leptin for 5 months. Magnetic resonance spectroscopy and dual-energy x-ray absorptiometry were performed to longitudinally evaluate marrow fat fraction and bone density at 0, 2.5, and 5 months, respectively. At the end of experiment, quantitative parameters of marrow adipocytes were assessed by histopathology. RESULTS Estrogen-deficient rabbits markedly exhibited expansion of marrow fat in a time-dependent manner, with a variation of marrow fat fraction (+19.7%) at 2.5 months relative to baseline conditions, and it was maintained until 5 months (+49.2%; all P < 0.001), which was accompanied by diminished bone density. Adipocyte diameter, density, and adipocytes area percentage in the OVX controls was increased by 50.7%, 76.3%, and 135.5%, respectively, relative to the sham controls (all P < 0.001). These OVX-induced marrow adiposity and bone loss were partly restored by leptin treatment. Treatment with leptin prevented OVX-induced increases in bone turnover in rabbits. CONCLUSIONS Early leptin administration inhibits the adipogenic effect of estrogen deficiency in terms of reverting marrow fat expansion seen in OVX rabbits. Magnetic resonance spectroscopy may be a useful tool for longitudinal and interventional assessments in osteoporosis.
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Marrow Adipose Tissue: Its Origin, Function, and Regulation in Bone Remodeling and Regeneration. Stem Cells Int 2018; 2018:7098456. [PMID: 29955232 PMCID: PMC6000863 DOI: 10.1155/2018/7098456] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 05/13/2018] [Indexed: 02/05/2023] Open
Abstract
Marrow adipose tissue (MAT) is a unique fat depot in the bone marrow and exhibits close relationship with hematopoiesis and bone homeostasis. MAT is distinct from peripheral adipose tissue in respect of its heterogeneous origin, site-specific distribution, and complex and perplexing function. Though MAT is indicated to function in hematopoiesis, skeletal remodeling, and energy metabolism, its explicit characterization still requires further research. In this review, we highlight recent advancement made in MAT regarding the origin and distribution of MAT, the local interaction with bone homeostasis and hematopoietic niche, the systemic endocrine regulation of metabolism, and MAT-based strategies to enhance bone formation.
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Low temperature exposure induces browning of bone marrow stem cell derived adipocytes in vitro. Sci Rep 2018; 8:4974. [PMID: 29563605 PMCID: PMC5862957 DOI: 10.1038/s41598-018-23267-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 03/06/2018] [Indexed: 02/08/2023] Open
Abstract
Brown and beige adipocytes are characterised as expressing the unique mitochondrial uncoupling protein (UCP)1 for which the primary stimulus in vivo is cold exposure. The extent to which cold-induced UCP1 activation can also be achieved in vitro, and therefore perform a comparable cellular function, is unknown. We report an in vitro model to induce adipocyte browning using bone marrow (BM) derived mesenchymal stem cells (MSC), which relies on differentiation at 32 °C instead of 37 °C. The low temperature promoted browning in adipogenic cultures, with increased adipocyte differentiation and upregulation of adipogenic and thermogenic factors, especially UCP1. Cells exhibited enhanced uncoupled respiration and metabolic adaptation. Cold-exposed differentiated cells showed a marked translocation of leptin to adipocyte nuclei, suggesting a previously unknown role for leptin in the browning process. These results indicate that BM-MSC can be driven to forming beige-like adipocytes in vitro by exposure to a reduced temperature. This in vitro model will provide a powerful tool to elucidate the precise role of leptin and related hormones in hitherto functions in the browning process.
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Ermetici F, Briganti S, Delnevo A, Cannaò P, Leo GD, Benedini S, Terruzzi I, Sardanelli F, Luzi L. Bone marrow fat contributes to insulin sensitivity and adiponectin secretion in premenopausal women. Endocrine 2018. [PMID: 28624865 DOI: 10.1007/s12020-017-1349-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
PURPOSE Bone marrow fat is a functionally distinct adipose tissue that may contribute to systemic metabolism. This study aimed at evaluating a possible association between bone marrow fat and insulin sensitivity indices. METHODS Fifty obese (n = 23) and non-obese (n = 27) premenopausal women underwent proton magnetic resonance spectroscopy to measure vertebral bone marrow fat content and unsaturation index at L4 level. Abdominal visceral, subcutaneous fat, and epicardial fat were also measured using magnetic resonance imaging. Bone mineral density was measured by dual-energy X-ray absorptiometry. Body composition was assessed by bioelectrical impedance analysis. Fasting serum glucose, insulin, lipids, adiponectin were measured; the insulin resistance index HOMA (HOMA-IR) was calculated. RESULTS Bone marrow fat content and unsaturation index were similar in obese and non-obese women (38.5 ± 0.1 vs. 38.6 ± 0.1%, p = 0.994; 0.162 ± 0.065 vs. 0.175 ± 0.048, p = 0.473, respectively). Bone marrow fat content negatively correlated with insulin and HOMA-IR (r = -0.342, r = -0.352, respectively, p = 0.01) and positively with high density lipoprotein cholesterol (r = 0.270, p = 0.043). From a multivariate regression model including lnHOMA-IR as a dependent variable and visceral, subcutaneous, epicardial fat, and bone marrow fat as independent variables, lnHOMA-IR was significantly associated with bone marrow fat (β = -0.008 ± 0.004, p = 0.04) and subcutaneous fat (β = 0.003 ± 0.001, p = 0.04). Bone marrow fat, among the other adipose depots, was a significant predictor of circulating adiponectin (β = 0.147 ± 0.060, p = 0.021). Bone marrow fat unsaturation index negatively correlated with visceral fat (r = -0.316, p = 0.026). CONCLUSIONS There is a relationship between bone marrow fat content and insulin sensitivity in obese and non-obese premenopausal women, possibly mediated by adiponectin secretion. Visceral fat does not seem to regulate bone marrow fat content while it may affect bone marrow fat composition.
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Affiliation(s)
- Federica Ermetici
- Endocrinology and Metabolism, IRCCS Policlinico San Donato, San Donato Milanese, Italy.
| | - Silvia Briganti
- Endocrinology and Metabolism, IRCCS Policlinico San Donato, San Donato Milanese, Italy
| | - Alessandra Delnevo
- Radiology Unit, IRCCS Policlinico San Donato, San Donato Milanese, Italy
| | - Paola Cannaò
- Radiology Unit, IRCCS Policlinico San Donato, San Donato Milanese, Italy
| | - Giovanni Di Leo
- Radiology Unit, IRCCS Policlinico San Donato, San Donato Milanese, Italy
| | - Stefano Benedini
- Endocrinology and Metabolism, IRCCS Policlinico San Donato, San Donato Milanese, Italy
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milano, Italy
| | - Ileana Terruzzi
- Diabetes Research Institute, Metabolism, Nutrigenomics and Cellular Differentiation Unit, San Raffaele Scientific Institute, Milano, Italy
| | - Francesco Sardanelli
- Radiology Unit, IRCCS Policlinico San Donato, San Donato Milanese, Italy
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milano, Italy
| | - Livio Luzi
- Endocrinology and Metabolism, IRCCS Policlinico San Donato, San Donato Milanese, Italy
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milano, Italy
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30
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Luo G, He Y, Yu X. Bone Marrow Adipocyte: An Intimate Partner With Tumor Cells in Bone Metastasis. Front Endocrinol (Lausanne) 2018; 9:339. [PMID: 30013512 PMCID: PMC6036292 DOI: 10.3389/fendo.2018.00339] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 06/05/2018] [Indexed: 02/05/2023] Open
Abstract
The high incidences of bone metastasis in patients with breast cancer, prostate cancer and lung cancer still remains a puzzling issue. The "seeds and soil" hypothesis suggested that bone marrow (soil) may provide a favorable "niche" for tumor cells (seed). When seeking for effective ways to prevent and treat tumor bone metastasis, most researchers focus on tumor cells (seed) but not the bone marrow microenvironment (soil). In reality, only a fraction of circulating tumor cells (CTCs) could survive and colonize in bone. Thus, the bone marrow microenvironment could ultimately determine the fate of tumor cells that have migrated to bone. Bone marrow adipocytes (BMAs) are abundant in the bone marrow microenvironment. Mounting evidence suggests that BMAs may play a dominant role in bone metastasis. BMAs could directly provide energy for tumor cells, enhance the tumor cell proliferation, and resistance to chemotherapy and radiotherapy. BMAs are also known for releasing some inflammatory factors and adipocytokines to promote or inhibit bone metastasis. In this review, we made a comprehensive summary for the interaction between BMAs and bone metastasis. More importantly, we discussed the potentially promising methods for the prevention and treatment of bone metastasis. Genetic disruption and pharmaceutical inhibition may be effective in inhibiting the formation and pro-tumor functions of BMAs.
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Affiliation(s)
- Guojing Luo
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology and Metabolism, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Yuedong He
- Department of Gynecology, West China Second University Hospital, Sichuan University, Chengdu, China
- Yuedong He
| | - Xijie Yu
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology and Metabolism, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
- *Correspondence: Xijie Yu ;
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Abstract
Bone marrow fat cells comprise the largest population of cells in the bone marrow cavity, a characteristic that has attracted the attention of scholars from different disciplines. The perception that bone marrow adipocytes are "inert space fillers" has been broken, and currently, bone marrow fat is unanimously considered to be the third largest fat depot, after subcutaneous fat and visceral fat. Bone marrow fat (BMF) acts as a metabolically active organ and plays an active role in energy storage, endocrine function, bone metabolism, and the bone metastasis of tumors. Bone marrow adipocytes (BMAs), as a component of the bone marrow microenvironment, influence hematopoiesis through direct contact with cells and the secretion of adipocyte-derived factors. They also influence the progression of hematologic diseases such as leukemia, multiple myeloma, and aplastic anemia, and may be a novel target when exploring treatments for related diseases in the future. Based on currently available data, this review describes the role of BMF in hematopoiesis as well as in the development of hematologic diseases.
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32
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The emerging role of bone marrow adipose tissue in bone health and dysfunction. J Mol Med (Berl) 2017; 95:1291-1301. [PMID: 29101431 DOI: 10.1007/s00109-017-1604-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 10/17/2017] [Accepted: 10/20/2017] [Indexed: 01/27/2023]
Abstract
Replacement of red hematopoietic bone marrow with yellow adipocyte-rich marrow is a conserved physiological process among mammals. The extent of this conversion is influenced by a wide array of pathological and non-pathological conditions. Of particular interest is the observation that some marrow adipocyte-inducing factors seem to oppose each other, for instance obesity and caloric restriction. Intriguingly, several important molecular characteristics of bone marrow adipose tissue (BMAT) are distinct from the classical depots of white and brown fat tissue. This depot of fat has recently emerged as an active part of the bone marrow niche that exerts paracrine and endocrine functions thereby controlling osteogenesis and hematopoiesis. While some functions of BMAT may be beneficial for metabolic adaptation and bone homeostasis, respectively, most findings assign bone fat a detrimental role during regenerative processes, such as hematopoiesis and osteogenesis. Thus, an improved understanding of the biological mechanisms leading to formation of BMAT, its molecular characteristics, and its physiological role in the bone marrow niche is warranted. Here we review the current understanding of BMAT biology and its potential implications for health and the development of pathological conditions.
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Mattiucci D, Maurizi G, Izzi V, Cenci L, Ciarlantini M, Mancini S, Mensà E, Pascarella R, Vivarelli M, Olivieri A, Leoni P, Poloni A. Bone marrow adipocytes support hematopoietic stem cell survival. J Cell Physiol 2017; 233:1500-1511. [PMID: 28574591 DOI: 10.1002/jcp.26037] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Accepted: 06/01/2017] [Indexed: 12/23/2022]
Abstract
In bone marrow (BM), hematopoietic elements are mingled with adipocytes (BM-A), which are the most abundant stromal component in the niche. BM-A progressively increase with aging, eventually occupying up to 50% of BM cavities. In this work, the role played by BM-A was explored by studying primary human BM-A isolated from hip surgery patients at the molecular level, through microarray analysis, and at the functional level, by assessing their relationship with primary human hematopoietic stem cells (HSC) by the long-term culture initiating cell (LTC-IC) assay. Findings demonstrated that BM-A are capable of supporting HSC survival in the LTC-IC assay, since after 5 weeks of co-culture, HSC were still able to proliferate and differentiate. Furthermore, critical molecules such as C-X-C motif chemokine 12 (CXCL12), interleukin (IL)-8, colony-stimulating factor 3 (CSF3), and leukaemia inhibitory factor (LIF), were expressed at similar levels in BM-A and in primary human BM mesenchymal stromal cells (BM-MSC), whereas IL-3 was higher in BM-A. Interestingly, BM-A displayed a different gene expression profile compared with subcutaneous adipose tissue adipocytes (AT-A) collected from abdominal surgery patients, especially in terms of regulation of lipid metabolism, stemness genes, and white-to-brown differentiation pathways. Accordingly, analysis of the gene pathways involved in hematopoiesis regulation showed that BM-A are more closely related to BM-MSC than to AT-A. The present data suggest that BM-A play a supporting role in the hematopoietic niche and directly sustain HSC survival.
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Affiliation(s)
- Domenico Mattiucci
- Dipartimento Scienze Cliniche e Molecolari, Clinica di Ematologia, Università Politecnica delle Marche, Ancona, Italy
| | - Giulia Maurizi
- Dipartimento Scienze Cliniche e Molecolari, Clinica di Ematologia, Università Politecnica delle Marche, Ancona, Italy
| | - Valerio Izzi
- Faculty of Biochemistry and Molecular Medicine, Center for Cell-Matrix Research and Biocenter Oulu, University of Oulu, Oulu, Finland
| | - Lorenzo Cenci
- Dipartimento Scienze Cliniche e Molecolari, Clinica di Ematologia, Università Politecnica delle Marche, Ancona, Italy
| | - Marco Ciarlantini
- Dipartimento Scienze Cliniche e Molecolari, Clinica di Ematologia, Università Politecnica delle Marche, Ancona, Italy
| | - Stefania Mancini
- Dipartimento Scienze Cliniche e Molecolari, Clinica di Ematologia, Università Politecnica delle Marche, Ancona, Italy
| | - Emanuela Mensà
- Cardiology Unit, Italian National Research Center on Aging (INRCA-IRCCS), Experimental Models in Clinical Pathology, INRCA-IRCCS National Institute, Ancona, Italy
| | | | - Marco Vivarelli
- Hepatobiliary and Abdominal Transplantation Surgery, Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy
| | - Attilio Olivieri
- Dipartimento Scienze Cliniche e Molecolari, Clinica di Ematologia, Università Politecnica delle Marche, Ancona, Italy
| | - Pietro Leoni
- Dipartimento Scienze Cliniche e Molecolari, Clinica di Ematologia, Università Politecnica delle Marche, Ancona, Italy
| | - Antonella Poloni
- Dipartimento Scienze Cliniche e Molecolari, Clinica di Ematologia, Università Politecnica delle Marche, Ancona, Italy
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Adipogenic niches for melanoma cell colonization and growth in bone marrow. J Transl Med 2017; 97:737-745. [PMID: 28218738 DOI: 10.1038/labinvest.2017.14] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 01/19/2017] [Accepted: 01/20/2017] [Indexed: 12/15/2022] Open
Abstract
Bone marrow (BM) adipocytes are abundant in BM and may be involved in the process of bone metastasis. However, their behaviors in metastatic BM niches during bone metastasis have not been fully explored. In this study, intracardiac transplantation of B16-F10 melanoma cells into immunocompetent C57BL/6 mice was performed. Tibial marrow sections were stained with hematoxylin and eosin, Masson's trichrome, tartrate-resistant acid phosphatase, and fatty acid-binding protein 4 (FABP4) and analyzed using a histomorphometric system. The results showed that the number of BM adipocytes rapidly increased in melanoma metastatic BM niches, which were in direct contact with metastasizing melanoma cells and acted as a tumor stromal population in the BM-melanoma niche. Melanoma cell-derived factors could enhance BM adipogenesis, which promotes melanoma cell proliferation and cell cycle transitions. Moreover, BM adipocytes might aid in the modification of the osteolytic BM microenvironment. These results indicate that an increase in the number of BM adipocytes in a metastatic BM niche may facilitate melanoma cell colonization and growth in BM. BM adipocytes might therefore support the development of bone metastases.
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35
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Hopkins AL, Nelson TAS, Guschina IA, Parsons LC, Lewis CL, Brown RC, Christian HC, Davies JS, Wells T. Unacylated ghrelin promotes adipogenesis in rodent bone marrow via ghrelin O-acyl transferase and GHS-R 1a activity: evidence for target cell-induced acylation. Sci Rep 2017; 7:45541. [PMID: 28361877 PMCID: PMC5374529 DOI: 10.1038/srep45541] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Accepted: 02/21/2017] [Indexed: 11/09/2022] Open
Abstract
Despite being unable to activate the cognate ghrelin receptor (GHS-R), unacylated ghrelin (UAG) possesses a unique activity spectrum that includes promoting bone marrow adipogenesis. Since a receptor mediating this action has not been identified, we re-appraised the potential interaction of UAG with GHS-R in the regulation of bone marrow adiposity. Surprisingly, the adipogenic effects of intra-bone marrow (ibm)-infused acylated ghrelin (AG) and UAG were abolished in male GHS-R-null mice. Gas chromatography showed that isolated tibial marrow adipocytes contain the medium-chain fatty acids utilised in the acylation of UAG, including octanoic acid. Additionally, immunohistochemistry and immunogold electron microscopy revealed that tibial marrow adipocytes show prominent expression of the UAG-activating enzyme ghrelin O-acyl transferase (GOAT), which is located in the membranes of lipid trafficking vesicles and in the plasma membrane. Finally, the adipogenic effect of ibm-infused UAG was completely abolished in GOAT-KO mice. Thus, the adipogenic action of exogenous UAG in tibial marrow is dependent upon acylation by GOAT and activation of GHS-R. This suggests that UAG is subject to target cell-mediated activation – a novel mechanism for manipulating hormone activity.
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Affiliation(s)
- Anna L Hopkins
- Neuroscience &Mental Health Research Institute, and School of Biosciences, Cardiff University, Museum Avenue, Cardiff, CF10 3AX, UK
| | - Timothy A S Nelson
- Neuroscience &Mental Health Research Institute, and School of Biosciences, Cardiff University, Museum Avenue, Cardiff, CF10 3AX, UK
| | - Irina A Guschina
- Neuroscience &Mental Health Research Institute, and School of Biosciences, Cardiff University, Museum Avenue, Cardiff, CF10 3AX, UK
| | - Lydia C Parsons
- Neuroscience &Mental Health Research Institute, and School of Biosciences, Cardiff University, Museum Avenue, Cardiff, CF10 3AX, UK
| | - Charlotte L Lewis
- Neuroscience &Mental Health Research Institute, and School of Biosciences, Cardiff University, Museum Avenue, Cardiff, CF10 3AX, UK
| | - Richard C Brown
- Neuroscience &Mental Health Research Institute, and School of Biosciences, Cardiff University, Museum Avenue, Cardiff, CF10 3AX, UK
| | - Helen C Christian
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, OX1 3QX, UK
| | - Jeffrey S Davies
- Institute of Life Science, School of Medicine, Swansea University, Swansea, SA2 8PP, UK
| | - Timothy Wells
- Neuroscience &Mental Health Research Institute, and School of Biosciences, Cardiff University, Museum Avenue, Cardiff, CF10 3AX, UK
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Sulston RJ, Cawthorn WP. Bone marrow adipose tissue as an endocrine organ: close to the bone? Horm Mol Biol Clin Investig 2017; 28:21-38. [PMID: 27149203 DOI: 10.1515/hmbci-2016-0012] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 03/25/2016] [Indexed: 02/06/2023]
Abstract
White adipose tissue (WAT) is a major endocrine organ, secreting a diverse range of hormones, lipid species, cytokines and other factors to exert diverse local and systemic effects. These secreted products, known as 'adipokines', contribute extensively to WAT's impact on physiology and disease. Adipocytes also exist in the bone marrow (BM), but unlike WAT, study of this bone marrow adipose tissue (MAT) has been relatively limited. We recently discovered that MAT contributes to circulating adiponectin, an adipokine that mediates cardiometabolic benefits. Moreover, we found that MAT expansion exerts systemic effects. Together, these observations identify MAT as an endocrine organ. Additional studies are revealing further secretory functions of MAT, including production of other adipokines, cytokines and lipids that exert local effects within bone. These observations suggest that, like WAT, MAT has secretory functions with diverse potential effects, both locally and systemically. A major limitation is that these findings are often based on in vitro approaches that may not faithfully recapitulate the characteristics and functions of BM adipocytes in vivo. This underscores the need to develop improved methods for in vivo analysis of MAT function, including more robust transgenic models for MAT targeting, and continued development of techniques for non-invasive analysis of MAT quantity and quality in humans. Although many aspects of MAT formation and function remain poorly understood, MAT is now attracting increasing research focus; hence, there is much promise for further advances in our understanding of MAT as an endocrine organ, and how MAT impacts human health and disease.
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37
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Li G, Xu Z, Zhuang A, Chang S, Hou L, Chen Y, Polat M, Wu D. Magnetic Resonance Spectroscopy-Detected Change in Marrow Adiposity Is Strongly Correlated to Postmenopausal Breast Cancer Risk. Clin Breast Cancer 2017; 17:239-244. [PMID: 28188108 DOI: 10.1016/j.clbc.2017.01.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 12/30/2016] [Accepted: 01/09/2017] [Indexed: 01/01/2023]
Abstract
PURPOSE To determine whether marrow fat fraction (FF) is correlated with postmenopausal breast cancer risk and clinicopathological characteristics of breast cancer. METHODS Fifty-six patients with newly diagnosed and histologically confirmed postmenopausal breast cancer and 56 healthy controls underwent serologic test and magnetic resonance spectroscopy-based FF measurements. Data were analyzed by logistic multivariate regression models to determine the independent predictors of breast cancer risk and clinicopathological characters of breast cancer. RESULTS Patients with breast cancer had higher FF than that of the controls. Marrow FF showed positive association with serum leptin levels (r = 0.607, P < .001) in the cases, but no relationship was found in the controls. In the univariate analysis, both levels of leptin and marrow FF were significantly associated with breast cancer risk and clinicopathological characteristics of breast cancer. In the multivariable model with adjustment for established breast cancer risk factors, serum leptin was a significant predictor of breast cancer risk (OR 1.746; 95% CI, 1.226-2.556) and clinicopathological characteristics of breast cancer including TNM, tumor size, lymph node status, and histological grade (OR 1.461-1.695); but when marrow FF was additionally added to the regression model, marrow FF but not leptin levels was observed to be an independent risk factor for breast cancer risk (OR 1.940; 95% CI, 1.306-2.910) and clinicopathological characteristics of breast cancer (OR 1.770-1.903). CONCLUSION Marrow adiposity is a predictor of postmenopausal breast cancer risk and clinicopathological characteristics of breast cancer.
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Affiliation(s)
- Guanwu Li
- Department of Radiology, Yueyang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
| | - Zheng Xu
- Xinzhuang Community Health Center, Shanghai, China
| | - Alex Zhuang
- Department of Radiology, Wayne State University, Detroit, MI
| | - Shixin Chang
- Department of Radiology, Yueyang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Lingmi Hou
- Breast Surgery, Affiliated Hospital of North Sichuan Medical College, Sichuan, China
| | - Yongsheng Chen
- Department of Radiology, Wayne State University, Detroit, MI
| | - Maki Polat
- School of Medicine and Public Health, University of Wisconsin, Madison, WI
| | - Dongmei Wu
- Shanghai Key Laboratory of Magnetic Resonance, East China Normal University, Shanghai, China
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38
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Breast Cancer Cell Colonization of the Human Bone Marrow Adipose Tissue Niche. Neoplasia 2016; 17:849-861. [PMID: 26696367 PMCID: PMC4688564 DOI: 10.1016/j.neo.2015.11.005] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Revised: 11/05/2015] [Accepted: 11/10/2015] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND/OBJECTIVES Bone is a preferred site of breast cancer metastasis, suggesting the presence of tissue-specific features that attract and promote the outgrowth of breast cancer cells. We sought to identify parameters of human bone tissue associated with breast cancer cell osteotropism and colonization in the metastatic niche. METHODS Migration and colonization patterns of MDA-MB-231-fLuc-EGFP (luciferase-enhanced green fluorescence protein) and MCF-7-fLuc-EGFP breast cancer cells were studied in co-culture with cancellous bone tissue fragments isolated from 14 hip arthroplasties. Breast cancer cell migration into tissues and toward tissue-conditioned medium was measured in Transwell migration chambers using bioluminescence imaging and analyzed as a function of secreted factors measured by multiplex immunoassay. Patterns of breast cancer cell colonization were evaluated with fluorescence microscopy and immunohistochemistry. RESULTS Enhanced MDA-MB-231-fLuc-EGFP breast cancer cell migration to bone-conditioned versus control medium was observed in 12/14 specimens (P = .0014) and correlated significantly with increasing levels of the adipokines/cytokines leptin (P = .006) and IL-1β (P = .001) in univariate and multivariate regression analyses. Fluorescence microscopy and immunohistochemistry of fragments underscored the extreme adiposity of adult human bone tissues and revealed extensive breast cancer cell colonization within the marrow adipose tissue compartment. CONCLUSIONS Our results show that breast cancer cells migrate to human bone tissue-conditioned medium in association with increasing levels of leptin and IL-1β, and colonize the bone marrow adipose tissue compartment of cultured fragments. Bone marrow adipose tissue and its molecular signals may be important but understudied components of the breast cancer metastatic niche.
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To assess differential features of marrow adiposity between postmenopausal women with osteoarthritis and osteoporosis using water/fat MRI. Menopause 2016; 24:105-111. [PMID: 27648658 DOI: 10.1097/gme.0000000000000732] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE To assess the differential features of marrow adiposity between osteoarthritis (OA) and osteoporosis (OP) in postmenopausal women using water/fat MRI. METHODS This cross-sectional study included 97 postmenopausal women (OA [n = 25], OA + osteopenia [n = 27], OA + OP [n = 23], and OP groups [n = 22]). Water/fat MRI, dual-energy x-ray absorptiometry and biochemical analysis were performed to assess vertebral marrow fat fraction, bone mineral density, and bone biomarkers, respectively. Harris Hip Score was recorded to evaluate hip function. RESULTS There were significant differences in marrow fat content among the OA, OA + osteopenia, and OA + OP groups, between OP and OA participants with normal bone mass or osteopenia (all P < 0.05); no significant difference was observed between OA + OP and OP groups. Serum levels of leptin and β-Crosslaps in OA with normal bone mass and osteopenic OA groups were higher than in OP group. Marrow fat fraction was inversely correlated with Harris Hip Score (r = -0.371, P = 0.013), bone mineral density (r = -0.554, P = 0.009) and leptin levels (r = -0.610, P < 0.001). In multivariate regression analysis, marrow fat fraction was found to have a consistent and unchanged inverse association with leptin levels (Sβ = -0.311, P = 0.002) and bone mineral density (Sβ = -0.265, P = 0.006) after adjusting for age, years since menopause, and body mass index. CONCLUSIONS Postmenopausal OA with OP have a phenotype with higher marrow adiposity. OA and OP could coexist, for the presence of a specific subgroup of OA with increased marrow fat accumulation and high risk of developing OP.
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Mechanisms underlying the association between obesity and Hodgkin lymphoma. Tumour Biol 2016; 37:13005-13016. [PMID: 27465553 DOI: 10.1007/s13277-016-5198-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 07/13/2016] [Indexed: 10/21/2022] Open
Abstract
A solid body of knowledge indicates that overweight and obese subjects are prone to develop cancer, aggressive disease, and death more than their lean counterparts. While obesity has been causally associated with various cancers, only a limited number of studies beheld the link with classical Hodgkin lymphoma (HL). Contemporary meta-analysis and prospective studies confirmed the association of body mass index with HL. Besides epidemiological evidence, excess adiposity is known to influence tumor behavior through adipokines, adipose-derived stem cell migration, and metabolism regulation, and by modulating immunoinflammatory response. Nevertheless, the obesity paradox has been described in few cancers. Considering that adipose tissue is an immunomodulatory organ, and that inflammation is the cornerstone of HL pathophysiology, the rationale for being causally related due to endocrine/paracrine interactions cannot be negligible. In this hypothesis-generating review, we explore the biologically plausible links between excess adiposity and HL in light of recent basic and clinical data, in order to create a basis for understanding the underlying mechanisms and foster applied research. The establishment of an association of excess adiposity with HL will determine public health preventive measures to fight obesity and eventually novel therapeutic approaches in HL patients.
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Zou L, Zhang G, Liu L, Chen C, Cao X, Cai J. Caveolin-1 is critical in the proliferative effect of leptin on osteoblasts through the activation of Akt. Mol Med Rep 2016; 14:1915-22. [PMID: 27430651 PMCID: PMC4991759 DOI: 10.3892/mmr.2016.5461] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2015] [Accepted: 05/24/2016] [Indexed: 11/06/2022] Open
Abstract
Osteoblasts are critical in bone remodeling and the repair of bone fractures. Leptin is involved in bone metabolism and osteoblast survival through the downstream signaling pathway, however, the exact mechanism of the effect of leptin on osteoblasts remains to be fully elucidated. In the present study, hFOB 1.19 cells were used to observe the effects of leptin on cell proliferation and apoptosis, and to investigate the underlying mechanism. The results confirmed that treatment of hFOB 1.19 cells with leptin significantly induced cell proliferation. Western blot analysis showed that the expression of caveolin‑1 and the activation of Akt in the cells treated with leptin were significantly increased, compared with the control cells. Additionally, inhibiting Akt activation eliminated the effects on cell proliferation induced by leptin. The rates of cell apoptosis and cell cycle distribution were examined using flow cytometry, which revealed a decrease in the apoptotic rate and an increase in the proportion of cells in the S phase. This indicated that leptin was capable of inducing cell proliferation by inhibiting apoptosis and stimulating cell progression to the S phase. Transfection of the cells with caveolin‑1 small interfering RNA showed that the activation of Akt induced by leptin was significantly inhibited. Furthermore, caveolin‑1 knockdown and inhibiting Akt activation eliminated the increased proliferation, increased proportion of cells in the S phase and increased anti‑apoptotic effects induced by leptin. Taken together, the data obtained in the present study demonstrated that caveolin‑1 was critical in the proliferative effect of leptin on osteoblasts via the activation of Akt.
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Affiliation(s)
- Lin Zou
- Department of Traumatic Orthopedic Surgery, The General Hospital of Jinan Military Command, Jinan, Shandong 250031, P.R. China
| | - Guichun Zhang
- Department of Traumatic Orthopedic Surgery, The General Hospital of Jinan Military Command, Jinan, Shandong 250031, P.R. China
| | - Lifeng Liu
- Department of Traumatic Orthopedic Surgery, The General Hospital of Jinan Military Command, Jinan, Shandong 250031, P.R. China
| | - Chen Chen
- Department of Traumatic Orthopedic Surgery, The General Hospital of Jinan Military Command, Jinan, Shandong 250031, P.R. China
| | - Xuecheng Cao
- Department of Traumatic Orthopedic Surgery, The General Hospital of Jinan Military Command, Jinan, Shandong 250031, P.R. China
| | - Jinfang Cai
- Department of Traumatic Orthopedic Surgery, The General Hospital of Jinan Military Command, Jinan, Shandong 250031, P.R. China
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Scheller EL, Cawthorn WP, Burr AA, Horowitz MC, MacDougald OA. Marrow Adipose Tissue: Trimming the Fat. Trends Endocrinol Metab 2016; 27:392-403. [PMID: 27094502 PMCID: PMC4875855 DOI: 10.1016/j.tem.2016.03.016] [Citation(s) in RCA: 137] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Revised: 03/25/2016] [Accepted: 03/29/2016] [Indexed: 02/07/2023]
Abstract
Marrow adipose tissue (MAT) is a unique fat depot, located in the skeleton, that has the potential to contribute to both local and systemic metabolic processes. In this review we highlight several recent conceptual developments pertaining to the origin and function of MAT adipocytes; consider the relationship of MAT to beige, brown, and white adipose depots; explore MAT expansion and turnover in humans and rodents; and discuss future directions for MAT research in the context of endocrine function and metabolic disease. MAT has the potential to exert both local and systemic effects on metabolic homeostasis, skeletal remodeling, hematopoiesis, and the development of bone metastases. The diversity of these functions highlights the breadth of the potential impact of MAT on health and disease.
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Affiliation(s)
- Erica L Scheller
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA; Division of Bone and Mineral Diseases, Department of Internal Medicine, Washington University, Saint Louis, MO 63110, USA.
| | - William P Cawthorn
- University/BHF Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Aaron A Burr
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Mark C Horowitz
- Department of Orthopaedics and Rehabilitation, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Ormond A MacDougald
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA; Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA.
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Abstract
Inflammation originating from the adipose tissue is considered to be one of the main driving forces for the development of insulin resistance and type 2 diabetes in obese individuals. Although a plethora of different immune cells shapes adipose tissue inflammation, this review is specifically focused on the contribution of macrophages that reside in adipose tissue in lean and obese conditions. Both conventional and tissue-specific functions of adipose tissue macrophages (ATMs) in lean and obese adipose tissue are discussed and linked with metabolic and inflammatory changes that occur during the development of obesity. Furthermore, we will address various circulating and adipose tissue-derived triggers that may be involved in shaping the ATM phenotype and underlie ATM function in lean and obese conditions. Finally, we will highlight how these changes affect adipose tissue inflammation and may be targeted for therapeutic interventions to improve insulin sensitivity in obese individuals.
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Affiliation(s)
- Lily Boutens
- Department of Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
- Nutrition, Metabolism and Genomics Group, Wageningen University, Bomenweg 2, 6703 HD, Wageningen, the Netherlands
| | - Rinke Stienstra
- Department of Medicine, Radboud University Medical Center, Nijmegen, the Netherlands.
- Nutrition, Metabolism and Genomics Group, Wageningen University, Bomenweg 2, 6703 HD, Wageningen, the Netherlands.
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Navein AE, Cooke EJ, Davies JR, Smith TG, Wells LHM, Ohazama A, Healy C, Sharpe PT, Evans SL, Evans BAJ, Votruba M, Wells T. Disrupted mitochondrial function in the Opa3L122P mouse model for Costeff Syndrome impairs skeletal integrity. Hum Mol Genet 2016; 25:2404-2416. [PMID: 27106103 PMCID: PMC5181626 DOI: 10.1093/hmg/ddw107] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 03/29/2016] [Accepted: 03/30/2016] [Indexed: 12/12/2022] Open
Abstract
Mitochondrial dysfunction connects metabolic disturbance with numerous pathologies, but the significance of mitochondrial activity in bone remains unclear. We have, therefore, characterized the skeletal phenotype in the Opa3L122P mouse model for Costeff syndrome, in which a missense mutation of the mitochondrial membrane protein, Opa3, impairs mitochondrial activity resulting in visual and metabolic dysfunction. Although widely expressed in the developing normal mouse head, Opa3 expression was restricted after E14.5 to the retina, brain, teeth and mandibular bone. Opa3 was also expressed in adult tibiae, including at the trabecular surfaces and in cortical osteocytes, epiphyseal chondrocytes, marrow adipocytes and mesenchymal stem cell rosettes. Opa3L122P mice displayed craniofacial abnormalities, including undergrowth of the lower mandible, accompanied in some individuals by cranial asymmetry and incisor malocclusion. Opa3L122P mice showed an 8-fold elevation in tibial marrow adiposity, due largely to increased adipogenesis. In addition, femoral length and cortical diameter and wall thickness were reduced, the weakening of the calcified tissue and the geometric component of strength reducing overall cortical strength in Opa3L122P mice by 65%. In lumbar vertebrae reduced vertebral body area and wall thickness were accompanied by a proportionate reduction in marrow adiposity. Although the total biomechanical strength of lumbar vertebrae was reduced by 35%, the strength of the calcified tissue (σmax) was proportionate to a 38% increase in trabecular number. Thus, mitochondrial function is important for the development and maintenance of skeletal integrity, impaired bone growth and strength, particularly in limb bones, representing a significant new feature of the Costeff syndrome phenotype.
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Affiliation(s)
- Alice E Navein
- School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK
| | - Esther J Cooke
- School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK
| | - Jennifer R Davies
- School of Optometry and Vision Sciences, Cardiff University, Cardiff CF24 4LU, UK
| | - Terence G Smith
- School of Optometry and Vision Sciences, Cardiff University, Cardiff CF24 4LU, UK
| | - Lois H M Wells
- School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK.,Caerleon Comprehensive School, Caerleon, Newport NP18 1NF, UK
| | - Atsushi Ohazama
- Department of Craniofacial Development and Stem Cell Biology, King's College London, Guy's Hospital, London SE1 9RT, UK
| | - Christopher Healy
- Department of Craniofacial Development and Stem Cell Biology, King's College London, Guy's Hospital, London SE1 9RT, UK
| | - Paul T Sharpe
- Department of Craniofacial Development and Stem Cell Biology, King's College London, Guy's Hospital, London SE1 9RT, UK
| | - Sam L Evans
- School of Engineering, Cardiff University, The Parade, Cardiff CF24 3AA, UK
| | - Bronwen A J Evans
- Institute of Molecular and Experimental Medicine, School of Medicine, Cardiff University, Heath Park, Cardiff CF14 4XN, UK
| | - Marcela Votruba
- School of Optometry and Vision Sciences, Cardiff University, Cardiff CF24 4LU, UK.,Cardiff Eye Unit, University Hospital of Wales, Heath Park, Cardiff CF14 4XW, UK
| | - Timothy Wells
- School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK
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Chandra Mouli K, Pragathi D, Naga Jyothi U, Shanmuga Kumar V, Himalaya Naik M, Balananda P, Suman B, Seshadri Reddy V, Vijaya T. Leptin inhibitors from fungal endophytes (LIFEs): Will be novel therapeutic drugs for obesity and its associated immune mediated diseases. Med Hypotheses 2016; 92:48-53. [PMID: 27241254 DOI: 10.1016/j.mehy.2016.04.032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Revised: 04/11/2016] [Accepted: 04/18/2016] [Indexed: 12/20/2022]
Abstract
Treatment of obesity and its associated immune mediated diseases is challenging due to impaired function of leptin system. Thus leptin is providing an interesting target for therapeutic intervention. Leptin, an adipose tissue-derived adipokine, displays a variety of immune functions, and regulate both innate and adaptive immune responses. The increased secretion of leptin (hyperleptinemia) and production of proinflammatory cytokines has been implicated in the pathogenesis of obesity-related immune diseases such as diabetes mellitus, hypertension, atherosclerosis, cancer, systemic lupus erythematosus, rheumatoid arthritis, crohn's disease and multiple sclerosis. These disorders are managed through antibiotics and by cytokines replacement. However, the effectiveness of cytokines coupled to the complexity of the cytokine network leads to severe side-effects, which can still occur after careful preclinical evaluation. In addition, synthetic immunotherapeutics carries a degree of risk, is time-consuming and expensive. Hence, the complexity of existing therapy and adverse effects emphasizes the need of an alternative approach for the management of immune dysfunction associated with obesity and its related diseases. For the aforementioned diseases that are related to leptin overabundance, new drugs blocking leptin signaling need to be generated. The research on the discovery of clinically important novel compounds from natural source is expanding due to their safety and no side effect. The fungal endophytes are the microbes that colonize internal tissue of plants without causing negative effects to the host. They produce plethora of substances of potential use to modern medicinal and pharmaceutical industry. The increasing body of evidence associated with application of bioactive metabolites derived from fungal endophytes in diverse disease states merits its use as therapeutic drugs. In particular, the saponins have been extensively proved to modulate the immune system, which has raised a significant interest in their potential as immunomodulators. Thus, our hypothesis is that the saponins derived from fungal endophytes can be explored as clinical applicable leptin inhibitors for treating immune mediated diseases.
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Affiliation(s)
- K Chandra Mouli
- Department of Biotechnology, Vikrama Simhapuri University, Nellore, Andhra Pradesh, India.
| | - D Pragathi
- Department of Biotechnology, Sri Venkateswara University, Tirupati, Andhra Pradesh, India
| | - U Naga Jyothi
- Department of Botany, Sri Venkateswara University, Tirupati, Andhra Pradesh, India
| | - V Shanmuga Kumar
- Department of Biotechnology, Sri Venkateswara University, Tirupati, Andhra Pradesh, India
| | - M Himalaya Naik
- Department of Biotechnology, Sri Venkateswara University, Tirupati, Andhra Pradesh, India
| | - P Balananda
- Department of Physiology, GIMSR, GITAM University, Visakhapatnam, Andhra Pradesh, India
| | - B Suman
- Department of Biochemistry, Sri Venkateswara University, Tirupati, Andhra Pradesh, India
| | - V Seshadri Reddy
- Department of Biochemistry, BPS Govt Medical College for Women, Sonepat, Haryana, India
| | - T Vijaya
- Department of Botany, Sri Venkateswara University, Tirupati, Andhra Pradesh, India
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van Niekerk G, Davis T, Engelbrecht AM. Bone marrow fat: What is it good for? Semin Arthritis Rheum 2016; 45:e14. [DOI: 10.1016/j.semarthrit.2015.09.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 09/22/2015] [Accepted: 09/28/2015] [Indexed: 10/23/2022]
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Hardouin P, Rharass T, Lucas S. Bone Marrow Adipose Tissue: To Be or Not To Be a Typical Adipose Tissue? Front Endocrinol (Lausanne) 2016; 7:85. [PMID: 27445987 PMCID: PMC4928601 DOI: 10.3389/fendo.2016.00085] [Citation(s) in RCA: 113] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 06/21/2016] [Indexed: 12/12/2022] Open
Abstract
Bone marrow adipose tissue (BMAT) emerges as a distinct fat depot whose importance has been proved in the bone-fat interaction. Indeed, it is well recognized that adipokines and free fatty acids released by adipocytes can directly or indirectly interfere with cells of bone remodeling or hematopoiesis. In pathological states, such as osteoporosis, each of adipose tissues - subcutaneous white adipose tissue (WAT), visceral WAT, brown adipose tissue (BAT), and BMAT - is differently associated with bone mineral density (BMD) variations. However, compared with the other fat depots, BMAT displays striking features that makes it a substantial actor in bone alterations. BMAT quantity is well associated with BMD loss in aging, menopause, and other metabolic conditions, such as anorexia nervosa. Consequently, BMAT is sensed as a relevant marker of a compromised bone integrity. However, analyses of BMAT development in metabolic diseases (obesity and diabetes) are scarce and should be, thus, more systematically addressed to better apprehend the bone modifications in that pathophysiological contexts. Moreover, bone marrow (BM) adipogenesis occurs throughout the whole life at different rates. Following an ordered spatiotemporal expansion, BMAT has turned to be a heterogeneous fat depot whose adipocytes diverge in their phenotype and their response to stimuli according to their location in bone and BM. In vitro, in vivo, and clinical studies point to a detrimental role of BM adipocytes (BMAs) throughout the release of paracrine factors that modulate osteoblast and/or osteoclast formation and function. However, the anatomical dissemination and the difficulties to access BMAs still hamper our understanding of the relative contribution of BMAT secretions compared with those of peripheral adipose tissues. A further characterization of the phenotype and the functional regulation of BMAs are ever more required. Based on currently available data and comparison with other fat tissues, this review addresses the originality of the BMAT with regard to its development, anatomy, metabolic properties, and response to physiological cues.
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Affiliation(s)
- Pierre Hardouin
- Laboratory of Pathophysiology of Inflammatory Bone Diseases PMOI, University of Littoral-Opale Coast ULCO, Boulogne sur Mer, France
| | - Tareck Rharass
- Laboratory of Pathophysiology of Inflammatory Bone Diseases PMOI, University of Littoral-Opale Coast ULCO, Boulogne sur Mer, France
| | - Stéphanie Lucas
- Laboratory of Pathophysiology of Inflammatory Bone Diseases PMOI, University of Littoral-Opale Coast ULCO, Boulogne sur Mer, France
- *Correspondence: Stéphanie Lucas,
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Cousin B, Casteilla L, Laharrague P, Luche E, Lorsignol A, Cuminetti V, Paupert J. Immuno-metabolism and adipose tissue: The key role of hematopoietic stem cells. Biochimie 2015; 124:21-26. [PMID: 26107410 DOI: 10.1016/j.biochi.2015.06.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 06/13/2015] [Indexed: 12/17/2022]
Abstract
The field of immunometabolism has come a long way in the past decade, leading to the emergence of a new role for white adipose tissue (WAT) that is now recognized to stand at the junction of immune and metabolic regulations. Interestingly, a crucial role of the abundant and heterogeneous immune population present in WAT has been proposed in the induction and development of metabolic diseases. Although a large body of data focused on mature immune cells, only few scattered studies are dedicated to leukocyte production, and the activity of hematopoietic stem cells (HSC) in these pathological states. Considering that blood cell production and the differentiation of HSCs and their progeny is orchestrated, in part, by complex interacting signals emanating from their microenvironment, it thus seems worth to better understand the relationships between metabolism and HSC. This review discusses the alterations of hematopoietic process described in metabolic diseases and focused on the emerging data concerning HSC present in WAT.
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Affiliation(s)
- B Cousin
- CNRS 5273, UMR STROMALab, F-31 432 Toulouse Cedex 4, France; Université de Toulouse 3, UPS, F-31 432 Toulouse Cedex 4, France; INSERM U1031, F-31 432 Toulouse Cedex 4, France; EFS Pyrénées -Méditerranée, BP 84225, F-31 432 Toulouse Cedex 4, France.
| | - L Casteilla
- CNRS 5273, UMR STROMALab, F-31 432 Toulouse Cedex 4, France; Université de Toulouse 3, UPS, F-31 432 Toulouse Cedex 4, France; INSERM U1031, F-31 432 Toulouse Cedex 4, France; EFS Pyrénées -Méditerranée, BP 84225, F-31 432 Toulouse Cedex 4, France
| | - P Laharrague
- CNRS 5273, UMR STROMALab, F-31 432 Toulouse Cedex 4, France; Université de Toulouse 3, UPS, F-31 432 Toulouse Cedex 4, France; INSERM U1031, F-31 432 Toulouse Cedex 4, France; EFS Pyrénées -Méditerranée, BP 84225, F-31 432 Toulouse Cedex 4, France; Laboratoire d'Hématologie, TSA 50032, F-31059 Toulouse, France
| | - E Luche
- CNRS 5273, UMR STROMALab, F-31 432 Toulouse Cedex 4, France; Université de Toulouse 3, UPS, F-31 432 Toulouse Cedex 4, France; INSERM U1031, F-31 432 Toulouse Cedex 4, France; EFS Pyrénées -Méditerranée, BP 84225, F-31 432 Toulouse Cedex 4, France
| | - A Lorsignol
- CNRS 5273, UMR STROMALab, F-31 432 Toulouse Cedex 4, France; Université de Toulouse 3, UPS, F-31 432 Toulouse Cedex 4, France; INSERM U1031, F-31 432 Toulouse Cedex 4, France; EFS Pyrénées -Méditerranée, BP 84225, F-31 432 Toulouse Cedex 4, France
| | - V Cuminetti
- CNRS 5273, UMR STROMALab, F-31 432 Toulouse Cedex 4, France; Université de Toulouse 3, UPS, F-31 432 Toulouse Cedex 4, France; INSERM U1031, F-31 432 Toulouse Cedex 4, France; EFS Pyrénées -Méditerranée, BP 84225, F-31 432 Toulouse Cedex 4, France
| | - J Paupert
- CNRS 5273, UMR STROMALab, F-31 432 Toulouse Cedex 4, France; Université de Toulouse 3, UPS, F-31 432 Toulouse Cedex 4, France; INSERM U1031, F-31 432 Toulouse Cedex 4, France; EFS Pyrénées -Méditerranée, BP 84225, F-31 432 Toulouse Cedex 4, France
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Van Pham P, Bui KHT, Ngo DQ, Doan TTP, Vu NB, Truong NH, Le DM, Phan NK. Expanded Adipose Tissue-Derived Stem Cells for Articular Cartilage Injury Treatment: A Safety and Efficacy Evaluation. Regen Med 2015. [DOI: 10.1007/978-1-4471-6542-2_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Upadhyay J, Farr OM, Mantzoros CS. The role of leptin in regulating bone metabolism. Metabolism 2015; 64:105-13. [PMID: 25497343 PMCID: PMC4532332 DOI: 10.1016/j.metabol.2014.10.021] [Citation(s) in RCA: 163] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Revised: 10/22/2014] [Accepted: 10/22/2014] [Indexed: 01/17/2023]
Abstract
Leptin was initially best known for its role in energy homeostasis and regulation of energy expenditure. In the past few years we have realized that leptin also plays a major role in neuroendocrine regulation and bone metabolism. Here, we review the literature the indirect and direct pathways through which leptin acts to influence bone metabolism and discuss bone abnormalities related to leptin deficiency in both animal and human studies. The clinical utility of leptin in leptin deficient individuals and its potential to improve metabolic bone disease are also discussed. We are beginning to understand the critical role leptin plays in bone metabolism; future randomized studies are needed to fully assess the potential and risk-benefit of leptin's use in metabolic bone disease particularly in leptin deficient individuals.
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Affiliation(s)
- Jagriti Upadhyay
- Division of Endocrinology, Boston VA Healthcare System/Harvard Medical School, Boston, MA 02215.
| | - Olivia M Farr
- Division of Endocrinology, Boston VA Healthcare System/Harvard Medical School, Boston, MA 02215
| | - Christos S Mantzoros
- Division of Endocrinology, Boston VA Healthcare System/Harvard Medical School, Boston, MA 02215
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