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Garcia-Martin R, Brandao BB, Thomou T, Altindis E, Kahn CR. Tissue differences in the exosomal/small extracellular vesicle proteome and their potential as indicators of altered tissue metabolism. Cell Rep 2022; 38:110277. [PMID: 35045290 PMCID: PMC8867597 DOI: 10.1016/j.celrep.2021.110277] [Citation(s) in RCA: 45] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 11/16/2021] [Accepted: 12/23/2021] [Indexed: 12/18/2022] Open
Abstract
Exosomes/small extracellular vesicles (sEVs) can serve as multifactorial mediators of cell-to-cell communication through their miRNA and protein cargo. Quantitative proteomic analysis of five cell lines representing metabolically important tissues reveals that each cell type has a unique sEV proteome. While classical sEV markers such as CD9/CD63/CD81 vary markedly in abundance, we identify six sEV markers (ENO1, GPI, HSPA5, YWHAB, CSF1R, and CNTN1) that are similarly abundant in sEVs of all cell types. In addition, each cell type has specific sEV markers. Using fat-specific Dicer-knockout mice with decreased white adipose tissue and increased brown adipose tissue, we show that these cell-type-specific markers can predict the changing origin of the serum sEVs. These results provide a valuable resource for understanding the sEV proteome of the cells and tissues important in metabolic homeostasis, identify unique sEV markers, and demonstrate how these markers can help in predicting the tissue of origin of serum sEVs. By performing comparative proteomics, Garcia-Martin et al. identify markers common to exosomes/sEVs from multiple cell types, as well as markers unique to each cell type. Using a lipodystrophy mouse model, they demonstrate the use of this sEV proteome dataset to predict the tissue of origin of circulating exosomes/sEVs in vivo.
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Affiliation(s)
- Ruben Garcia-Martin
- Joslin Diabetes Center, Harvard Medical School, One Joslin Place, Boston, MA 02215, USA
| | - Bruna Brasil Brandao
- Joslin Diabetes Center, Harvard Medical School, One Joslin Place, Boston, MA 02215, USA
| | - Thomas Thomou
- Joslin Diabetes Center, Harvard Medical School, One Joslin Place, Boston, MA 02215, USA
| | - Emrah Altindis
- Boston College Biology Department, Higgins Hall, 140 Commonwealth Avenue, Chestnut Hill, MA 02476, USA.
| | - C Ronald Kahn
- Joslin Diabetes Center, Harvard Medical School, One Joslin Place, Boston, MA 02215, USA.
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2
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El Ouaamari A, O-Sullivan I, Shirakawas J, Basile G, Wenwei Z, Sandra R, Thomou T, Liew CW, Kulkarni R, Unterman T. SAT-150 Forkhead Box Protein O1 (foxo1) Regulates Hepatic Serine Protease Inhibitor B1 (serpinb1) Expression In A Cell Non-autonomous Fashion. J Endocr Soc 2019. [PMCID: PMC6552238 DOI: 10.1210/js.2019-sat-150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Forkhead box O (FoxO) proteins are major targets of insulin action, and FoxO1 mediates insulin’s effects on hepatic glucose metabolism. We previously reported that serine protease inhibitor B1 (serpinB1) is a liver-secreted factor (hepatokine) that promotes adaptive β-cell proliferation in response to insulin resistance in liver-specific insulin receptor knockout (LIRKO) mice. Here, we report that FoxO1 promotes serpinB1 expression in hepatic insulin resistance in a cell non-autonomous manner. Mice lacking both the insulin receptor and FoxO1 in the liver (LIRFKO) exhibited lower β-cell mass than LIRKO mice due to attenuated β-cell proliferation. Hepatic expression of serpinb1mRNA and protein levels were increased in the LIRKO mice, whereas in the LIRFKO mice, these levels returned to those in control mice. Furthermore, liver-specific expression of constitutively active FoxO1 increased hepatic serpinB1 mRNA and protein levels. Conversely, serpinB1 mRNA and protein levels were reduced in FoxOKO mice lacking FoxO proteins in the liver. ChIP experiments indicated that FoxO1 binds to three distinct DNA sites located ~9 kb upstream of the serpinb1 gene in primary mouse hepatocytes and that this binding is enhanced in LIRKO hepatocytes. However, although adenoviral expression of wildtype or constitutively active FoxO1 and insulin treatment regulated other known FoxO1 target genes (IGFBP-1, PEPCK, G6Pase), it did not alter serpinB1 expression in mouse primary hepatocytes. These results indicate that liver FoxO1 promotes serpinB1 expression in hepatic insulin resistance and that cell non-autonomous mechanisms contribute to FoxO1-dependent effects on hepatic serpinB1 expression.
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Affiliation(s)
| | | | | | | | - Zhang Wenwei
- Univ of IL and Jesse Brown VAMC, Chicago, IL, United States
| | | | - Thomas Thomou
- Integrative Physiology & Metabolism, Joslin Diabetes Center, BOSTON, MA, United States
| | - Chong Wee Liew
- Cell and Molec Physiology, Joslin Diabetes Center, Boston, MA, United States
| | | | - Terry Unterman
- Univ of IL and Jesse Brown VAMC, Chicago, IL, United States
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3
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El Ouaamari A, O-Sullivan I, Shirakawa J, Basile G, Zhang W, Roger S, Thomou T, Xu S, Qiang G, Liew CW, Kulkarni RN, Unterman TG. Forkhead box protein O1 (FoxO1) regulates hepatic serine protease inhibitor B1 (serpinB1) expression in a non-cell-autonomous fashion. J Biol Chem 2018; 294:1059-1069. [PMID: 30459233 DOI: 10.1074/jbc.ra118.006031] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 11/15/2018] [Indexed: 12/13/2022] Open
Abstract
FoxO proteins are major targets of insulin action, and FoxO1 mediates the effects of insulin on hepatic glucose metabolism. We reported previously that serpinB1 is a liver-secreted factor (hepatokine) that promotes adaptive β-cell proliferation in response to insulin resistance in the liver-specific insulin receptor knockout (LIRKO) mouse. Here we report that FoxO1 plays a critical role in promoting serpinB1 expression in hepatic insulin resistance in a non-cell-autonomous manner. Mice lacking both the insulin receptor and FoxO1 (LIRFKO) exhibit reduced β-cell mass compared with LIRKO mice because of attenuation of β-cell proliferation. Although hepatic expression of serpinB1 mRNA and protein levels was increased in LIRKO mice, both the mRNA and protein levels returned to control levels in LIRFKO mice. Furthermore, liver-specific expression of constitutively active FoxO1 in transgenic mice induced an increase in hepatic serpinB1 mRNA and protein levels in refed mice. Conversely, serpinB1 mRNA and protein levels were reduced in mice lacking FoxO proteins in the liver. ChIP studies demonstrated that FoxO1 binds to three distinct sites located ∼9 kb upstream of the serpinb1 gene in primary mouse hepatocytes and that this binding is enhanced in hepatocytes from LIRKO mice. However, adenoviral expression of WT or constitutively active FoxO1 and insulin treatment are sufficient to regulate other FoxO1 target genes (IGFBP-1 and PEPCK) but not serpinB1 expression in mouse primary hepatocytes. These results indicate that liver FoxO1 promotes serpinB1 expression in hepatic insulin resistance and that non-cell-autonomous factors contribute to FoxO1-dependent effects on serpinB1 expression in the liver.
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Affiliation(s)
- Abdelfattah El Ouaamari
- From the Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Harvard Medical School, Harvard Stem Cell Institute, Boston, Massachusetts 02215
| | - InSug O-Sullivan
- the Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois, Chicago, Illinois 60612.,the Medical Research Service, Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois 60612
| | - Jun Shirakawa
- From the Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Harvard Medical School, Harvard Stem Cell Institute, Boston, Massachusetts 02215
| | - Giorgio Basile
- From the Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Harvard Medical School, Harvard Stem Cell Institute, Boston, Massachusetts 02215
| | - Wenwei Zhang
- the Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois, Chicago, Illinois 60612.,the Medical Research Service, Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois 60612
| | - Sandra Roger
- From the Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Harvard Medical School, Harvard Stem Cell Institute, Boston, Massachusetts 02215
| | - Thomas Thomou
- the Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts 02215, and
| | - Shanshan Xu
- the Department of Physiology and Biophysics, College of Medicine, University of Illinois, Chicago, Illinois 60612
| | - Guifen Qiang
- the Department of Physiology and Biophysics, College of Medicine, University of Illinois, Chicago, Illinois 60612
| | - Chong Wee Liew
- the Department of Physiology and Biophysics, College of Medicine, University of Illinois, Chicago, Illinois 60612
| | - Rohit N Kulkarni
- From the Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Harvard Medical School, Harvard Stem Cell Institute, Boston, Massachusetts 02215,
| | - Terry G Unterman
- the Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois, Chicago, Illinois 60612, .,the Medical Research Service, Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois 60612
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Rao TN, Gupta MK, Softic S, Wang LD, Jang YC, Thomou T, Bezy O, Kulkarni RN, Kahn CR, Wagers AJ. Attenuation of PKCδ enhances metabolic activity and promotes expansion of blood progenitors. EMBO J 2018; 37:embj.2018100409. [PMID: 30446598 PMCID: PMC6293338 DOI: 10.15252/embj.2018100409] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 09/08/2018] [Accepted: 09/12/2018] [Indexed: 12/21/2022] Open
Abstract
A finely tuned balance of self‐renewal, differentiation, proliferation, and survival governs the pool size and regenerative capacity of blood‐forming hematopoietic stem and progenitor cells (HSPCs). Here, we report that protein kinase C delta (PKCδ) is a critical regulator of adult HSPC number and function that couples the proliferative and metabolic activities of HSPCs. PKCδ‐deficient mice showed a pronounced increase in HSPC numbers, increased competence in reconstituting lethally irradiated recipients, enhanced long‐term competitive advantage in serial transplantation studies, and an augmented HSPC recovery during stress. PKCδ‐deficient HSPCs also showed accelerated proliferation and reduced apoptosis, but did not exhaust in serial transplant assays or induce leukemia. Using inducible knockout and transplantation models, we further found that PKCδ acts in a hematopoietic cell‐intrinsic manner to restrict HSPC number and bone marrow regenerative function. Mechanistically, PKCδ regulates HSPC energy metabolism and coordinately governs multiple regulators within signaling pathways implicated in HSPC homeostasis. Together, these data identify PKCδ as a critical regulator of HSPC signaling and metabolism that acts to limit HSPC expansion in response to physiological and regenerative demands.
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Affiliation(s)
- Tata Nageswara Rao
- Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Harvard University, Cambridge, MA, USA .,Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, Boston, MA, USA
| | - Manoj K Gupta
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, Boston, MA, USA
| | - Samir Softic
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Boston, MA, USA.,Division of Gastroenterology, Hepatology and Nutrition, Boston Children's Hospital, Boston, MA, USA
| | - Leo D Wang
- Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Harvard University, Cambridge, MA, USA.,Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, Boston, MA, USA.,Division of Pediatric Hematology/Oncology/Stem Cell Transplantation, Dana-Farber/Boston Children's Center for Cancer and Blood Disorders, Boston, MA, USA
| | - Young C Jang
- Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Harvard University, Cambridge, MA, USA.,Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, Boston, MA, USA
| | - Thomas Thomou
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Boston, MA, USA
| | - Olivier Bezy
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Boston, MA, USA
| | - Rohit N Kulkarni
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, Boston, MA, USA
| | - C Ronald Kahn
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Boston, MA, USA
| | - Amy J Wagers
- Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Harvard University, Cambridge, MA, USA .,Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, Boston, MA, USA
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Reis FCG, Branquinho JLO, Brandão BB, Guerra BA, Silva ID, Frontini A, Thomou T, Sartini L, Cinti S, Kahn CR, Festuccia WT, Kowaltowski AJ, Mori MA. Fat-specific Dicer deficiency accelerates aging and mitigates several effects of dietary restriction in mice. Aging (Albany NY) 2017; 8:1201-22. [PMID: 27241713 PMCID: PMC4931827 DOI: 10.18632/aging.100970] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 05/15/2016] [Indexed: 01/08/2023]
Abstract
Aging increases the risk of type 2 diabetes, and this can be prevented by dietary restriction (DR). We have previously shown that DR inhibits the downregulation of miRNAs and their processing enzymes - mainly Dicer - that occurs with aging in mouse white adipose tissue (WAT). Here we used fat-specific Dicer knockout mice (AdicerKO) to understand the contributions of adipose tissue Dicer to the metabolic effects of aging and DR. Metabolomic data uncovered a clear distinction between the serum metabolite profiles of Lox control and AdicerKO mice, with a notable elevation of branched-chain amino acids (BCAA) in AdicerKO. These profiles were associated with reduced oxidative metabolism and increased lactate in WAT of AdicerKO mice and were accompanied by structural and functional changes in mitochondria, particularly under DR. AdicerKO mice displayed increased mTORC1 activation in WAT and skeletal muscle, where Dicer expression is not affected. This was accompanied by accelerated age-associated insulin resistance and premature mortality. Moreover, DR-induced insulin sensitivity was abrogated in AdicerKO mice. This was reverted by rapamycin injection, demonstrating that insulin resistance in AdicerKO mice is caused by mTORC1 hyperactivation. Our study evidences a DR-modulated role for WAT Dicer in controlling metabolism and insulin resistance.
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Affiliation(s)
- Felipe C G Reis
- Department of Biophysics, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Jéssica L O Branquinho
- Department of Biophysics, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Bruna B Brandão
- Department of Biophysics, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Beatriz A Guerra
- Department of Biophysics, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Ismael D Silva
- Department of Gynecology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Andrea Frontini
- Department of Public Health, Experimental and Forensic Medicine, University of Pavia, Pavia, Italy
| | - Thomas Thomou
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, MA 02215, USA
| | - Loris Sartini
- Department of Clinical and Experimental Medicine, Università Politecnica delle Marche, Ancona, Italy
| | - Saverio Cinti
- Department of Clinical and Experimental Medicine, Università Politecnica delle Marche, Ancona, Italy
| | - C Ronald Kahn
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, MA 02215, USA
| | - William T Festuccia
- Departament of Physiology, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Alicia J Kowaltowski
- Department of Biochemistry, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Marcelo A Mori
- Department of Biophysics, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil.,Department of Biochemistry and Tissue Biology, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, Brazil
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6
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Thomou T, Mori MA, Dreyfuss JM, Konishi M, Sakaguchi M, Wolfrum C, Rao TN, Winnay JN, Garcia-Martin R, Grinspoon SK, Gorden P, Kahn CR. Adipose-derived circulating miRNAs regulate gene expression in other tissues. Nature 2017; 542:450-455. [PMID: 28199304 PMCID: PMC5330251 DOI: 10.1038/nature21365] [Citation(s) in RCA: 981] [Impact Index Per Article: 140.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Accepted: 01/04/2017] [Indexed: 12/13/2022]
Abstract
Adipose tissue is a major site of energy storage and has a role in the regulation of metabolism through the release of adipokines. Here we show that mice with an adipose-tissue-specific knockout of the microRNA (miRNA)-processing enzyme Dicer (ADicerKO), as well as humans with lipodystrophy, exhibit a substantial decrease in levels of circulating exosomal miRNAs. Transplantation of both white and brown adipose tissue-brown especially-into ADicerKO mice restores the level of numerous circulating miRNAs that are associated with an improvement in glucose tolerance and a reduction in hepatic Fgf21 mRNA and circulating FGF21. This gene regulation can be mimicked by the administration of normal, but not ADicerKO, serum exosomes. Expression of a human-specific miRNA in the brown adipose tissue of one mouse in vivo can also regulate its 3' UTR reporter in the liver of another mouse through serum exosomal transfer. Thus, adipose tissue constitutes an important source of circulating exosomal miRNAs, which can regulate gene expression in distant tissues and thereby serve as a previously undescribed form of adipokine.
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Affiliation(s)
- Thomas Thomou
- Section on Integrative Physiology & Metabolism, Joslin Diabetes Center and Harvard Medical School, Boston, MA
| | - Marcelo A. Mori
- Department of Biochemistry and Tissue Biology, State University of Campinas, Campinas, Brazil
| | - Jonathan M. Dreyfuss
- Bioinformatics Core, Joslin Diabetes Center and Harvard Medical School, Boston, MA
- Department of Biomedical Engineering, Boston University, Boston, MA
| | - Masahiro Konishi
- Section on Integrative Physiology & Metabolism, Joslin Diabetes Center and Harvard Medical School, Boston, MA
| | - Masaji Sakaguchi
- Section on Integrative Physiology & Metabolism, Joslin Diabetes Center and Harvard Medical School, Boston, MA
| | - Christian Wolfrum
- ETHZ, Department of Health Sciences and Metabolism, Zurich, Switzerland
| | - Tata Nageswara Rao
- Section on Integrative Physiology & Metabolism, Joslin Diabetes Center and Harvard Medical School, Boston, MA
- Department of Biomedicine, Experimental Hematology, University Hospital Basel, Switzerland
| | - Jonathon N. Winnay
- Section on Integrative Physiology & Metabolism, Joslin Diabetes Center and Harvard Medical School, Boston, MA
| | - Ruben Garcia-Martin
- Section on Integrative Physiology & Metabolism, Joslin Diabetes Center and Harvard Medical School, Boston, MA
| | - Steven K. Grinspoon
- MGH Program in Nutritional Metabolism, Massachusetts General Hospital and Harvard Medical School, Boston, MA
| | - Phillip Gorden
- Diabetes, Endocrinology and Obesity Branch, NIDDK, National Institutes of Health, Bethesda, MD
| | - C. Ronald Kahn
- Section on Integrative Physiology & Metabolism, Joslin Diabetes Center and Harvard Medical School, Boston, MA
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Torriani M, Srinivasa S, Fitch KV, Thomou T, Wong K, Petrow E, Kahn CR, Cypess AM, Grinspoon SK. Dysfunctional Subcutaneous Fat With Reduced Dicer and Brown Adipose Tissue Gene Expression in HIV-Infected Patients. J Clin Endocrinol Metab 2016; 101:1225-34. [PMID: 26756119 PMCID: PMC4803164 DOI: 10.1210/jc.2015-3993] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT HIV patients are at an increased risk for cardiometabolic disease secondary to depot-specific alterations in adipose function, but mechanisms remain poorly understood. OBJECTIVE The endoribonuclease Dicer has been linked to the modulation of brown and white adipocyte differentiation. We previously demonstrated that Dicer knockout mice undergo transformation of brown adipose tissue to white adipose tissue and develop a lipodystrophic phenotype. We hypothesized reduced Dicer and brown adipose tissue gene expression from nonlipomatous sc fat among HIV patients with a lipodystrophic phenotype. DESIGN Eighteen HIV (nine with and without lipodystrophic changes in fat distribution, characterized by excess dorsocervical adipose tissue [DCAT]) and nine non-HIV subjects underwent punch biopsy of abdominal sc fat to determine expression of Dicer and other adipose-related genes. RESULTS HIV subjects with long-duration antiretroviral use demonstrated excess DCAT vs non-HIV subjects (9.8 ± 1.0 vs 6.6 ± 0.8 cm(2), P = .02) with similar body mass index. Dicer expression was decreased in abdominal sc fat of HIV vs non-HIV (4.88 [1.91, 11.93] vs 17.69 [10.72, 47.91], P = .01), as were PPARα, ZIC1, PRDM16, DIO2, and HSP60 (all P ≤ .03). Moreover, the expression of Dicer (2.49 [0.02, 4.88] vs 11.20 [4.83, 21.45], P = .006), brown fat (PPARα [P = .002], ZIC1 [P = .004], LHX8 [P = .03], PRDM16 [P = .0008], PAT2 [P = .008], P2RX5 [P = .02]), beige fat (TMEM26 [P = .004], CD137 [P = .008]), and other genes (DIO2 [P = .002], leptin [P = .003], HSP60 [P = .0004]) was further decreased in abdominal sc fat comparing HIV subjects with vs without excess DCAT. Down-regulation of Dicer in the abdominal sc fat correlated with the down-regulation of all brown and beige fat genes (all P ≤ .01). CONCLUSION Our results demonstrate dysfunctional sc adipose tissue marked by reduced Dicer in relationship to the down-regulation of brown and beige fat-related genes in lipodystrophic HIV patients and may provide a novel mechanism for metabolic dysregulation. A strategy to increase browning of white adipose tissue may improve cardiometabolic health in HIV.
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Affiliation(s)
- Martin Torriani
- Program in Nutritional Metabolism (M.T., S.S., K.V.F., K.W., E.P., S.K.G.) and Division of Musculoskeletal Imaging and Intervention (M.T.), Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114; Section on Integrative Physiology and Metabolism (T.T., C.R.K., A.M.C.), Joslin Diabetes Center and Harvard Medical School, Boston, Massachusetts 02215; and Translational Physiology Section, Diabetes, Endocrinology, and Obesity Branch, National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Diseases (A.M.C.), Bethesda, Maryland 20892
| | - Suman Srinivasa
- Program in Nutritional Metabolism (M.T., S.S., K.V.F., K.W., E.P., S.K.G.) and Division of Musculoskeletal Imaging and Intervention (M.T.), Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114; Section on Integrative Physiology and Metabolism (T.T., C.R.K., A.M.C.), Joslin Diabetes Center and Harvard Medical School, Boston, Massachusetts 02215; and Translational Physiology Section, Diabetes, Endocrinology, and Obesity Branch, National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Diseases (A.M.C.), Bethesda, Maryland 20892
| | - Kathleen V Fitch
- Program in Nutritional Metabolism (M.T., S.S., K.V.F., K.W., E.P., S.K.G.) and Division of Musculoskeletal Imaging and Intervention (M.T.), Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114; Section on Integrative Physiology and Metabolism (T.T., C.R.K., A.M.C.), Joslin Diabetes Center and Harvard Medical School, Boston, Massachusetts 02215; and Translational Physiology Section, Diabetes, Endocrinology, and Obesity Branch, National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Diseases (A.M.C.), Bethesda, Maryland 20892
| | - Thomas Thomou
- Program in Nutritional Metabolism (M.T., S.S., K.V.F., K.W., E.P., S.K.G.) and Division of Musculoskeletal Imaging and Intervention (M.T.), Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114; Section on Integrative Physiology and Metabolism (T.T., C.R.K., A.M.C.), Joslin Diabetes Center and Harvard Medical School, Boston, Massachusetts 02215; and Translational Physiology Section, Diabetes, Endocrinology, and Obesity Branch, National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Diseases (A.M.C.), Bethesda, Maryland 20892
| | - Kimberly Wong
- Program in Nutritional Metabolism (M.T., S.S., K.V.F., K.W., E.P., S.K.G.) and Division of Musculoskeletal Imaging and Intervention (M.T.), Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114; Section on Integrative Physiology and Metabolism (T.T., C.R.K., A.M.C.), Joslin Diabetes Center and Harvard Medical School, Boston, Massachusetts 02215; and Translational Physiology Section, Diabetes, Endocrinology, and Obesity Branch, National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Diseases (A.M.C.), Bethesda, Maryland 20892
| | - Eva Petrow
- Program in Nutritional Metabolism (M.T., S.S., K.V.F., K.W., E.P., S.K.G.) and Division of Musculoskeletal Imaging and Intervention (M.T.), Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114; Section on Integrative Physiology and Metabolism (T.T., C.R.K., A.M.C.), Joslin Diabetes Center and Harvard Medical School, Boston, Massachusetts 02215; and Translational Physiology Section, Diabetes, Endocrinology, and Obesity Branch, National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Diseases (A.M.C.), Bethesda, Maryland 20892
| | - C Ronald Kahn
- Program in Nutritional Metabolism (M.T., S.S., K.V.F., K.W., E.P., S.K.G.) and Division of Musculoskeletal Imaging and Intervention (M.T.), Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114; Section on Integrative Physiology and Metabolism (T.T., C.R.K., A.M.C.), Joslin Diabetes Center and Harvard Medical School, Boston, Massachusetts 02215; and Translational Physiology Section, Diabetes, Endocrinology, and Obesity Branch, National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Diseases (A.M.C.), Bethesda, Maryland 20892
| | - Aaron M Cypess
- Program in Nutritional Metabolism (M.T., S.S., K.V.F., K.W., E.P., S.K.G.) and Division of Musculoskeletal Imaging and Intervention (M.T.), Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114; Section on Integrative Physiology and Metabolism (T.T., C.R.K., A.M.C.), Joslin Diabetes Center and Harvard Medical School, Boston, Massachusetts 02215; and Translational Physiology Section, Diabetes, Endocrinology, and Obesity Branch, National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Diseases (A.M.C.), Bethesda, Maryland 20892
| | - Steven K Grinspoon
- Program in Nutritional Metabolism (M.T., S.S., K.V.F., K.W., E.P., S.K.G.) and Division of Musculoskeletal Imaging and Intervention (M.T.), Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114; Section on Integrative Physiology and Metabolism (T.T., C.R.K., A.M.C.), Joslin Diabetes Center and Harvard Medical School, Boston, Massachusetts 02215; and Translational Physiology Section, Diabetes, Endocrinology, and Obesity Branch, National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Diseases (A.M.C.), Bethesda, Maryland 20892
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Khamaisi M, Katagiri S, Keenan H, Park K, Maeda Y, Li Q, Qi W, Thomou T, Eschuk D, Tellechea A, Veves A, Huang C, Orgill DP, Wagers A, King GL. PKCδ inhibition normalizes the wound-healing capacity of diabetic human fibroblasts. J Clin Invest 2016; 126:837-53. [PMID: 26808499 DOI: 10.1172/jci82788] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 12/08/2015] [Indexed: 12/21/2022] Open
Abstract
Abnormal fibroblast function underlies poor wound healing in patients with diabetes; however, the mechanisms that impair wound healing are poorly defined. Here, we evaluated fibroblasts from individuals who had type 1 diabetes (T1D) for 50 years or more (Medalists, n = 26) and from age-matched controls (n = 7). Compared with those from controls, Medalist fibroblasts demonstrated a reduced migration response to insulin, lower VEGF expression, and less phosphorylated AKT (p-AKT), but not p-ERK, activation. Medalist fibroblasts were also functionally less effective at wound closure in nude mice. Activation of the δ isoform of protein kinase C (PKCδ) was increased in postmortem fibroblasts from Medalists, fibroblasts from living T1D subjects, biopsies of active wounds of living T1D subjects, and granulation tissues from mice with streptozotocin-induced diabetes. Diabetes-induced PKCD mRNA expression was related to a 2-fold increase in the mRNA half-life. Pharmacologic inhibition and siRNA-mediated knockdown of PKCδ or expression of a dominant-negative isoform restored insulin signaling of p-AKT and VEGF expression in vitro and improved wound healing in vivo. Additionally, increasing PKCδ expression in control fibroblasts produced the same abnormalities as those seen in Medalist fibroblasts. Our results indicate that persistent PKCδ elevation in fibroblasts from diabetic patients inhibits insulin signaling and function to impair wound healing and suggest PKCδ inhibition as a potential therapy to improve wound healing in diabetic patients.
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9
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Ussar S, Lee KY, Dankel SN, Boucher J, Haering MF, Kleinridders A, Thomou T, Xue R, Macotela Y, Cypess AM, Tseng YH, Mellgren G, Kahn CR. ASC-1, PAT2, and P2RX5 are cell surface markers for white, beige, and brown adipocytes. Sci Transl Med 2015; 6:247ra103. [PMID: 25080478 DOI: 10.1126/scitranslmed.3008490] [Citation(s) in RCA: 146] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
White, beige, and brown adipocytes are developmentally and functionally distinct but often occur mixed together within individual depots. To target white, beige, and brown adipocytes for diagnostic or therapeutic purposes, a better understanding of the cell surface properties of these cell types is essential. Using a combination of in silico, in vitro, and in vivo methods, we have identified three new cell surface markers of adipose cell types. The amino acid transporter ASC-1 is a white adipocyte-specific cell surface protein, with little or no expression in brown adipocytes, whereas the amino acid transporter PAT2 and the purinergic receptor P2RX5 are cell surface markers expressed in classical brown and beige adipocytes in mice. These markers also selectively mark brown/beige and white adipocytes in human tissue. Thus, ASC-1, PAT2, and P2RX5 are membrane surface proteins that may serve as tools to identify and target white and brown/beige adipocytes for therapeutic purposes.
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Affiliation(s)
- Siegfried Ussar
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center and Harvard Medical School, Boston, MA 02215, USA. Institute for Diabetes and Obesity, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Kevin Y Lee
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center and Harvard Medical School, Boston, MA 02215, USA
| | - Simon N Dankel
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center and Harvard Medical School, Boston, MA 02215, USA. Department of Clinical Science, University of Bergen, 5020 Bergen, Norway. Hormone Laboratory, Haukeland University Hospital, 5020 Bergen, Norway
| | - Jeremie Boucher
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center and Harvard Medical School, Boston, MA 02215, USA
| | - Max-Felix Haering
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center and Harvard Medical School, Boston, MA 02215, USA
| | - Andre Kleinridders
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center and Harvard Medical School, Boston, MA 02215, USA
| | - Thomas Thomou
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center and Harvard Medical School, Boston, MA 02215, USA
| | - Ruidan Xue
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center and Harvard Medical School, Boston, MA 02215, USA
| | - Yazmin Macotela
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center and Harvard Medical School, Boston, MA 02215, USA
| | - Aaron M Cypess
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center and Harvard Medical School, Boston, MA 02215, USA
| | - Yu-Hua Tseng
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center and Harvard Medical School, Boston, MA 02215, USA
| | - Gunnar Mellgren
- Department of Clinical Science, University of Bergen, 5020 Bergen, Norway. Hormone Laboratory, Haukeland University Hospital, 5020 Bergen, Norway
| | - C Ronald Kahn
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center and Harvard Medical School, Boston, MA 02215, USA.
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10
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Mori MA, Thomou T, Boucher J, Lee KY, Lallukka S, Kim JK, Torriani M, Yki-Järvinen H, Grinspoon SK, Cypess AM, Kahn CR. Altered miRNA processing disrupts brown/white adipocyte determination and associates with lipodystrophy. J Clin Invest 2014; 124:3339-51. [PMID: 24983316 DOI: 10.1172/jci73468] [Citation(s) in RCA: 134] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Accepted: 05/22/2014] [Indexed: 12/17/2022] Open
Abstract
miRNAs are important regulators of biological processes in many tissues, including the differentiation and function of brown and white adipocytes. The endoribonuclease dicer is a major component of the miRNA-processing pathway, and in adipose tissue, levels of dicer have been shown to decrease with age, increase with caloric restriction, and influence stress resistance. Here, we demonstrated that mice with a fat-specific KO of dicer develop a form of lipodystrophy that is characterized by loss of intra-abdominal and subcutaneous white fat, severe insulin resistance, and enlargement and "whitening" of interscapular brown fat. Additionally, KO of dicer in cultured brown preadipocytes promoted a white adipocyte-like phenotype and reduced expression of several miRNAs. Brown preadipocyte whitening was partially reversed by expression of miR-365, a miRNA known to promote brown fat differentiation; however, introduction of other miRNAs, including miR-346 and miR-362, also contributed to reversal of the loss of the dicer phenotype. Interestingly, fat samples from patients with HIV-related lipodystrophy exhibited a substantial downregulation of dicer mRNA expression. Together, these findings indicate the importance of miRNA processing in white and brown adipose tissue determination and provide a potential link between this process and HIV-related lipodystrophy.
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11
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Tchkonia T, Thomou T, Zhu Y, Karagiannides I, Pothoulakis C, Jensen MD, Kirkland JL. Mechanisms and metabolic implications of regional differences among fat depots. Cell Metab 2013; 17:644-656. [PMID: 23583168 PMCID: PMC3942783 DOI: 10.1016/j.cmet.2013.03.008] [Citation(s) in RCA: 443] [Impact Index Per Article: 40.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Fat distribution is closely linked to metabolic disease risk. Distribution varies with sex, genetic background, disease state, certain drugs and hormones, development, and aging. Preadipocyte replication and differentiation, developmental gene expression, susceptibility to apoptosis and cellular senescence, vascularity, inflammatory cell infiltration, and adipokine secretion vary among depots, as do fatty-acid handling and mechanisms of enlargement with positive-energy and loss with negative-energy balance. How interdepot differences in these molecular, cellular, and pathophysiological properties are related is incompletely understood. Whether fat redistribution causes metabolic disease or whether it is a marker of underlying processes that are primarily responsible is an open question.
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Affiliation(s)
| | - Thomas Thomou
- Joslin Diabetes Center, Harvard Medical School, Boston, MA 02215, USA
| | - Yi Zhu
- Robert and Arlene Kogod Center on Aging
| | - Iordanes Karagiannides
- Inflammatory Bowel Disease Center, Division of Digestive Diseases, Department of Medicine, University of California at Los Angeles, Los Angeles, CA 90095, USA
| | - Charalabos Pothoulakis
- Inflammatory Bowel Disease Center, Division of Digestive Diseases, Department of Medicine, University of California at Los Angeles, Los Angeles, CA 90095, USA
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12
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Mori MA, Raghavan P, Thomou T, Boucher J, Robida-Stubbs S, Macotela Y, Russell SJ, Kirkland JL, Blackwell TK, Kahn CR. Role of microRNA processing in adipose tissue in stress defense and longevity. Cell Metab 2012; 16:336-47. [PMID: 22958919 PMCID: PMC3461823 DOI: 10.1016/j.cmet.2012.07.017] [Citation(s) in RCA: 188] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Revised: 06/14/2012] [Accepted: 07/12/2012] [Indexed: 12/21/2022]
Abstract
Excess adipose tissue is associated with metabolic disease and reduced life span, whereas caloric restriction decreases these risks. Here we show that as mice age, there is downregulation of Dicer and miRNA processing in adipose tissue resulting in decreases of multiple miRNAs. A similar decline of Dicer with age is observed in C. elegans. This is prevented in both species by caloric restriction. Decreased Dicer expression also occurs in preadipocytes from elderly humans and can be produced in cells by exposure to oxidative stress or UV radiation. Knockdown of Dicer in cells results in premature senescence, and fat-specific Dicer knockout renders mice hypersensitive to oxidative stress. Finally, Dicer loss-of-function mutations in worms reduce life span and stress tolerance, while intestinal overexpression of Dicer confers stress resistance. Thus, regulation of miRNA processing in adipose-related tissues plays an important role in longevity and the ability of an organism to respond to environmental stress and age-related disease.
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Affiliation(s)
- Marcelo A Mori
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, MA 02215, USA
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13
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Karagiannides I, Bakirtzi K, Kokkotou E, Stavrakis D, Margolis KG, Thomou T, Giorgadze N, Kirkland JL, Pothoulakis C. Role of substance P in the regulation of glucose metabolism via insulin signaling-associated pathways. Endocrinology 2011; 152:4571-80. [PMID: 22009727 PMCID: PMC3230056 DOI: 10.1210/en.2011-1170] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Substance P (SP), encoded by the tachykinin 1 (Tac1) gene, is the most potent tachykinin ligand for the high-affinity neurokinin-1 receptor (NK-1R). We previously reported that NK-1R-deficient mice show less weight gain and reduced circulating levels of leptin and insulin in response to a high-fat diet (HFD) and demonstrated the presence of functional NK-1R in isolated human preadipocytes. Here we assessed the effects of SP on weight gain in response to HFD and determined glucose metabolism in Tac1-deficient (Tac1(-/-)) mice. The effect of SP on the expression of molecules that may predispose to reduced glucose uptake was also determined in isolated human mesenteric, omental, and sc preadipocytes. We show that although weight accumulation in response to HFD was similar between Tac1(-/-) mice and wild-type littermates, Tac1(-/-) mice demonstrated lower glucose and leptin and increased adiponectin blood levels and showed improved responses to insulin challenge after HFD. SP stimulated phosphorylation of c-Jun N-terminal kinase, protein kinase C, mammalian target of rapamycin, and inhibitory serine insulin receptor substrate-1 phosphorylation in human preadipocytes in vitro. Preincubation of human mesenteric preadipocytes with the protein kinase C pseudosubstrate inhibitor reduced insulin receptor substrate 1 phosphorylation in response to SP. Lastly, SP also induced insulin receptor substrate-1 phosphorylation in mature human sc adipocytes. Our results demonstrate an important role for SP in adipose tissue responses and obesity-associated pathologies. These novel SP effects on molecules that enhance insulin resistance at the adipocyte level may reflect an important role for this peptide in the pathophysiology of type 2 diabetes.
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Affiliation(s)
- Iordanes Karagiannides
- Inflammatory Bowel Disease Center, Division of Digestive Diseases, David Geffen School of Medicine, University of California at Los Angeles, 675 Charles E. Young Drive, Los Angeles, CA 90095, USA
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14
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Reichert B, Yasmeen R, Jeyakumar SM, Yang F, Thomou T, Alder H, Duester G, Maiseyeu A, Mihai G, Harrison EH, Rajagopalan S, Kirkland JL, Ziouzenkova O. Concerted action of aldehyde dehydrogenases influences depot-specific fat formation. Mol Endocrinol 2011; 25:799-809. [PMID: 21436255 DOI: 10.1210/me.2010-0465] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Vitamin A metabolite retinoic acid (RA) regulates life-sustaining differentiation processes and metabolic homeostasis. The aldehyde dehydrogenase-1 (Aldh1) family of enzymes (Aldh1a1, a2, and a3) catalyzes RA production from retinaldehyde and thereby controls concentrations of this transcriptionally active metabolite. The hierarchy of Aldh1 functions in adipose tissue has not been elucidated. We hypothesized that Aldh1 enzymes produce endogenous RA and regulate adipogenesis and fat formation in a fat depot-specific manner. We demonstrate that adipogenesis in vitro is accompanied by RA production generated primarily by Aldh1a1. In Aldh1a1-deficient adipocytes, adipogenesis is impaired compared with wild-type adipocytes due to markedly reduced expression of PPARγ regulated through zinc-finger protein 423 (ZFP423)-dependent mechanisms. These effects were recovered to some extent either by RA stimulation or overexpression of any of the Aldh1 enzymes in Aldh1a1(-/-) cells arguing that Aldh1a1 plays a dominant role in autocrine RA production. In vivo studies in C57/BL6 and Aldh1a1(-/-) mice on a regular diet revealed that multiple Aldh1 enzymes regulate differences in the formation of sc and visceral fat. In Aldh1a1(-/-) mice, visceral fat essentially lacked all Aldh1 expression. This loss of RA-producing enzymes was accompanied by 70% decreased expression of ZFP423, PPARγ, and Fabp4 in visceral fat of Aldh1a1(-/-) vs. wild-type mice and by the predominant loss of visceral fat. Subcutaneous fat of Aldh1a1(-/-) mice expressed Aldh1a3 for RA production that was sufficient to maintain expression of ZFP423 and PPARγ and sc fat mass. Our data suggest a paradigm for regulation of fat depots through the concerted action of Aldh1 enzymes that establish RA-dependent tandem regulation of transcription factors ZFP423 and PPARγ in a depot-specific manner.
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Affiliation(s)
- Barbara Reichert
- Department of Human Nutrition, Ohio State University, Columbus, Ohio, 43210, USA
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15
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Tchoukalova YD, Koutsari C, Votruba SB, Tchkonia T, Giorgadze N, Thomou T, Kirkland JL, Jensen MD. Sex- and depot-dependent differences in adipogenesis in normal-weight humans. Obesity (Silver Spring) 2010; 18:1875-80. [PMID: 20300084 PMCID: PMC2906626 DOI: 10.1038/oby.2010.56] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
To elucidate cellular mechanisms of sex-related differences in fat distribution, we determined body fat distribution (dual-energy X-ray absorptiometry and single-slice abdominal computed tomography (CT)), adipocyte size, adipocyte number, and proportion of early-differentiated adipocytes (aP2(+)CD68(-)) in the stromovascular fraction (SVF) in the upper and lower body of normal-weight healthy men (n = 12) and premenopausal women (n = 20) (age: 18-49 years, BMI: 18-26 kg/m(2)). Women had more subcutaneous and less visceral fat than men. The proportion of early differentiated adipocytes in the subcutaneous adipose tissue SVF of women was greater than in men (P = 0.01), especially in the femoral depot, although in vitro adipogenesis, as assessed by peroxisome proliferator activated receptor-γ (PPARγ) expression, was not increased in femoral preadipocytes cultured from women compared with men. In women, differentiation of femoral preadipocytes was less than that of abdominal subcutaneous preadipocytes (P = 0.04), and femoral subcutaneous preadipocytes tended to be more resistant to tumor necrosis factor-α (TNFα)-induced apoptosis (P = 0.06). Thus, turnover and utilization of the preadipocyte pool may be reduced in lower vs. the upper-body fat in women. Collectively, these data indicate that the microenvironment, rather than differences in inherent properties of preadipocytes between genders, may explain the gynoid obesity phenotype and higher percent body fat in women compared to men.
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16
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Sepe A, Tchkonia T, Thomou T, Zamboni M, Kirkland JL. Aging and regional differences in fat cell progenitors - a mini-review. Gerontology 2010; 57:66-75. [PMID: 20110661 DOI: 10.1159/000279755] [Citation(s) in RCA: 158] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2009] [Accepted: 12/02/2009] [Indexed: 12/14/2022] Open
Abstract
Fat mass and fat tissue distribution change dramatically throughout life. In old age, fat becomes dysfunctional and is redistributed from subcutaneous to intra-abdominal visceral depots as well as other ectopic sites, including bone marrow, muscle and the liver. These changes are associated with increased risk of metabolic syndrome. Fat tissue is a nutrient storage, endocrine and immune organ that undergoes renewal throughout the lifespan. Preadipocytes, which account for 15-50% of cells in fat tissue, give rise to new fat cells. With aging, declines in preadipocyte proliferation and differentiation likely contribute to increased systemic exposure to lipotoxic free fatty acids. Age-related fat tissue inflammation is related to changes that occur in preadipocytes and macrophages in a fat depot-dependent manner. Fat tissue inflammation frequently leads to further reduction in adipogenesis with aging, more lipotoxicity and activation of cellular stress pathways that, in turn, exacerbate inflammatory responses of preadipocytes and immune cells, establishing self-perpetuating cycles that lead to systemic dysfunction. In this review, we will consider how inherent, age-related, depot-dependent alterations in preadipocyte function contribute to age-related fat tissue redistribution and metabolic dysfunction.
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Affiliation(s)
- Anna Sepe
- Department of Biomedical and Surgical Sciences, Division of Geriatrics, University of Verona, Verona, Italy
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17
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Cartwright MJ, Schlauch K, Lenburg ME, Tchkonia T, Pirtskhalava T, Cartwright A, Thomou T, Kirkland JL. Aging, depot origin, and preadipocyte gene expression. J Gerontol A Biol Sci Med Sci 2010; 65:242-51. [PMID: 20106964 PMCID: PMC2904595 DOI: 10.1093/gerona/glp213] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Fat distribution changes with aging. Inherent changes in fat cell progenitors may
contribute because fat cells turn over throughout life. To define mechanisms, gene
expression was profiled in preadipocytes cultured from epididymal and perirenal depots of
young and old rats. 8.4% of probe sets differed significantly between depots, particularly
developmental genes. Only 0.02% differed with aging, despite using less stringent criteria
than for comparing depots. Twenty-five genes selected based on fold change with aging were
analyzed in preadipocytes from additional young, middle-aged, and old animals by
polymerase chain reaction. Thirteen changed significantly with aging, 13 among depots, and
9 with both. Genes involved in inflammation, stress, and differentiation changed with
aging, as occurs in fat tissue. Age-related changes were greater in perirenal than
epididymal preadipocytes, consistent with larger declines in replication and adipogenesis
in perirenal preadipocytes. Thus, age-related changes in preadipocyte gene expression
differ among depots, potentially contributing to fat redistribution and dysfunction.
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18
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Gross K, Karagiannides I, Thomou T, Koon HW, Bowe C, Kim H, Giorgadze N, Tchkonia T, Pirtskhalava T, Kirkland JL, Pothoulakis C. Substance P promotes expansion of human mesenteric preadipocytes through proliferative and antiapoptotic pathways. Am J Physiol Gastrointest Liver Physiol 2009; 296:G1012-9. [PMID: 19282377 PMCID: PMC2696212 DOI: 10.1152/ajpgi.90351.2008] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
White adipose tissue is intimately involved in the regulation of immunity and inflammation. We reported that human mesenteric preadipocytes express the substance P (SP)-mediated neurokinin-1 receptor (NK-1R), which signals proinflammatory responses. Here we tested the hypothesis that SP promotes proliferation and survival of human mesenteric preadipocytes and investigated responsible mechanism(s). Preadipocytes were isolated from mesenteric fat biopsies during gastric bypass surgery. Proliferative and antiapoptotic responses were delineated in 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS), bromodeoxyuridine (BrdU), caspase-3, and TUNEL assays, as well as Western immunoanalysis. SP (10(-7) M) increased MTS and proliferation (BrdU) and time dependently (15-30 min) induced Akt, EGF receptor, IGF receptor, integrin alphaVbeta3, phosphatidylinositol 3-kinase, and PKC-theta phosphorylation. Furthermore, pharmacological antagonism of Akt and PKC-theta activation significantly attenuated SP-induced preadipocyte proliferation. Exposure of preadipocytes to the proapoptotic Fas ligand (FasL, 100 microM) resulted in nuclear DNA fragmentation (TUNEL assay), as well as increased cleaved poly (ADP-ribose) polymerase, cleaved caspase-7, and caspase-3 expression. Cotreatment with SP almost completely abolished these responses in a NK-1R-dependent fashion. SP (10(-7) M) also time dependently stimulated expression 4E binding protein 1 and phosphorylation of p70 S6 kinase, which increased protein translation efficiency. SP increases preadipocyte viability, reduces apoptosis, and stimulates proliferation, possibly via cell cycle upregulation and increased protein translation efficiency. SP-induced proliferative and antiapoptotic pathways in fat depots may contribute to development of the creeping fat and inflammation characteristic of Crohn's disease.
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Affiliation(s)
- Kara Gross
- Gastrointestinal Neuropeptide Center, Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts; Inflammatory Bowel Disease Center, Division of Digestive Diseases, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; Columbia University Medical Center, Department of Pediatrics, New York, New York; and Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, Minnesota
| | - Iordanes Karagiannides
- Gastrointestinal Neuropeptide Center, Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts; Inflammatory Bowel Disease Center, Division of Digestive Diseases, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; Columbia University Medical Center, Department of Pediatrics, New York, New York; and Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, Minnesota
| | - Thomas Thomou
- Gastrointestinal Neuropeptide Center, Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts; Inflammatory Bowel Disease Center, Division of Digestive Diseases, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; Columbia University Medical Center, Department of Pediatrics, New York, New York; and Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, Minnesota
| | - Hon Wai Koon
- Gastrointestinal Neuropeptide Center, Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts; Inflammatory Bowel Disease Center, Division of Digestive Diseases, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; Columbia University Medical Center, Department of Pediatrics, New York, New York; and Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, Minnesota
| | - Collin Bowe
- Gastrointestinal Neuropeptide Center, Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts; Inflammatory Bowel Disease Center, Division of Digestive Diseases, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; Columbia University Medical Center, Department of Pediatrics, New York, New York; and Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, Minnesota
| | - Ho Kim
- Gastrointestinal Neuropeptide Center, Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts; Inflammatory Bowel Disease Center, Division of Digestive Diseases, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; Columbia University Medical Center, Department of Pediatrics, New York, New York; and Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, Minnesota
| | - Nino Giorgadze
- Gastrointestinal Neuropeptide Center, Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts; Inflammatory Bowel Disease Center, Division of Digestive Diseases, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; Columbia University Medical Center, Department of Pediatrics, New York, New York; and Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, Minnesota
| | - Tamara Tchkonia
- Gastrointestinal Neuropeptide Center, Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts; Inflammatory Bowel Disease Center, Division of Digestive Diseases, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; Columbia University Medical Center, Department of Pediatrics, New York, New York; and Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, Minnesota
| | - Tamara Pirtskhalava
- Gastrointestinal Neuropeptide Center, Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts; Inflammatory Bowel Disease Center, Division of Digestive Diseases, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; Columbia University Medical Center, Department of Pediatrics, New York, New York; and Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, Minnesota
| | - James L. Kirkland
- Gastrointestinal Neuropeptide Center, Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts; Inflammatory Bowel Disease Center, Division of Digestive Diseases, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; Columbia University Medical Center, Department of Pediatrics, New York, New York; and Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, Minnesota
| | - Charalabos Pothoulakis
- Gastrointestinal Neuropeptide Center, Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts; Inflammatory Bowel Disease Center, Division of Digestive Diseases, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; Columbia University Medical Center, Department of Pediatrics, New York, New York; and Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, Minnesota
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19
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Tchkonia T, Pirtskhalava T, Thomou T, Cartwright MJ, Wise B, Karagiannides I, Shpilman A, Lash TL, Becherer JD, Kirkland JL. Increased TNFalpha and CCAAT/enhancer-binding protein homologous protein with aging predispose preadipocytes to resist adipogenesis. Am J Physiol Endocrinol Metab 2007; 293:E1810-9. [PMID: 17911345 DOI: 10.1152/ajpendo.00295.2007] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Fat depot sizes peak in middle age but decrease by advanced old age. This phenomenon is associated with ectopic fat deposition, decreased adipocyte size, impaired differentiation of preadipocytes into fat cells, decreased adipogenic transcription factor expression, and increased fat tissue inflammatory cytokine generation. To define the mechanisms contributing to impaired adipogenesis with aging, we examined the release of TNFalpha, which inhibits adipogenesis, and the expression of CCAAT/enhancer-binding protein (C/EBP) homologous protein (CHOP), which blocks activity of adipogenic C/EBP family members, in preadipocytes cultured from young, middle-aged, and old rats. Medium conditioned by fat tissue, as well as preadipocytes, from old rats impeded lipid accumulation by preadipocytes from young animals. More TNFalpha was released by preadipocytes from old than young rats. Differences in TNFalpha-converting enzyme, TNFalpha degradation, or the presence of macrophages in cultures were not responsible. TNFalpha induced rat preadipocyte CHOP expression. CHOP was higher in undifferentiated preadipocytes from old than younger animals. Overexpression of CHOP in young rat preadipocytes inhibited lipid accumulation. TNFalpha short interference RNA reduced CHOP and partially restored lipid accumulation in old rat preadipocytes. CHOP normally increases during late differentiation, potentially modulating the process. This late increase in CHOP was not affected substantially by aging: CHOP was similar in differentiating preadipocytes and fat tissue from old and young animals. Hypoglycemia, which normally causes an adaptive increase in CHOP, was less effective in inducing CHOP in preadipocytes from old than younger animals. Thus increased TNFalpha release by undifferentiated preadipocytes with elevated basal CHOP contributes to impaired adipogenesis with aging.
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Affiliation(s)
- Tamara Tchkonia
- Evans Department of Medicine, Boston Univ. Medical Center, 88 E. Newton St., Robinson 2, Boston, MA 02118, USA
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Guo W, Pirtskhalava T, Tchkonia T, Xie W, Thomou T, Han J, Wang T, Wong S, Cartwright A, Hegardt FG, Corkey BE, Kirkland JL. Aging results in paradoxical susceptibility of fat cell progenitors to lipotoxicity. Am J Physiol Endocrinol Metab 2007; 292:E1041-51. [PMID: 17148751 DOI: 10.1152/ajpendo.00557.2006] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Aging is associated with metabolic syndrome, tissue damage by cytotoxic lipids, and altered fatty acid handling. Fat tissue dysfunction may contribute to these processes. This could result, in part, from age-related changes in preadipocytes, since they give rise to new fat cells throughout life. To test this hypothesis, preadipocytes cultured from rats of different ages were exposed to oleic acid, the most abundant fatty acyl moiety in fat tissue and the diet. At fatty acid concentrations at which preadipocytes from young animals remained viable, cells from old animals accumulated lipid in multiple small lipid droplets and died, with increased apoptotic index, caspase activity, BAX, and p53. Rather than inducing apoptosis, oleic acid promoted adipogenesis in preadipocytes from young animals, with appearance of large lipid droplets. CCAAT/enhancer-binding protein-alpha (C/EBPalpha) and peroxisome proliferator-activated receptor-gamma (PPARgamma) increased to a greater extent in cells from young than old animals after oleate exposure. Oleic acid, but not glucose, oxidation was impaired in preadipocytes and fat cells from old animals. Expression of carnitine palmitoyltransferase (CPT)-1, which catalyzes the rate-limiting step in fatty acid beta-oxidation, was not reduced in preadipocytes from old animals. At lower fatty acid levels, constitutively active CPT I expression enhanced beta-oxidation. At higher levels, CPT I was not as effective in enhancing beta-oxidation in preadipocytes from old as young animals, suggesting that mitochondrial dysfunction may contribute. Consistent with this, medium-chain acyl-CoA dehydrogenase expression was reduced in preadipocytes from old animals. Thus preadipocyte fatty acid handling changes with aging, with increased susceptibly to lipotoxicity and impaired fatty acid-induced adipogenesis and beta-oxidation.
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Affiliation(s)
- Wen Guo
- Evans Department of Medicine, Obesity Research Center, Boston University Medical Center, 88 E. Newton St., Boston, MA 02118, USA
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Tchkonia T, Lenburg M, Thomou T, Giorgadze N, Frampton G, Pirtskhalava T, Cartwright A, Cartwright M, Flanagan J, Karagiannides I, Gerry N, Forse RA, Tchoukalova Y, Jensen MD, Pothoulakis C, Kirkland JL. Identification of depot-specific human fat cell progenitors through distinct expression profiles and developmental gene patterns. Am J Physiol Endocrinol Metab 2007; 292:E298-307. [PMID: 16985259 DOI: 10.1152/ajpendo.00202.2006] [Citation(s) in RCA: 262] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Anatomically separate fat depots differ in size, function, and contribution to pathological states, such as the metabolic syndrome. We isolated preadipocytes from different human fat depots to determine whether the basis for this variation is partly attributable to differences in inherent properties of fat cell progenitors. We found that genome-wide expression profiles of primary preadipocytes cultured in parallel from abdominal subcutaneous, mesenteric, and omental fat depots were distinct. Interestingly, visceral fat was not homogeneous. Preadipocytes from one of the two main visceral depots, mesenteric fat, had an expression profile closer to that of subcutaneous than omental preadipocytes, the other main visceral depot. Expression of genes that regulate early development, including homeotic genes, differed extensively among undifferentiated preadipocytes isolated from different fat depots. These profiles were confirmed by real-time PCR analysis of preadipocytes from additional lean and obese male and female subjects. We made preadipocyte strains from single abdominal subcutaneous and omental preadipocytes by expressing telomerase. Depot-specific developmental gene expression profiles persisted for 40 population doublings in these strains. Thus, human fat cell progenitors from different regions are effectively distinct, consistent with different fat depots being separate mini-organs.
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Affiliation(s)
- Tamara Tchkonia
- Boston University Medical Center, 88 East Newton St., Boston, MA 02118, USA
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Tchkonia T, Giorgadze N, Pirtskhalava T, Thomou T, DePonte M, Koo A, Forse RA, Chinnappan D, Martin-Ruiz C, von Zglinicki T, Kirkland JL. Fat depot-specific characteristics are retained in strains derived from single human preadipocytes. Diabetes 2006; 55:2571-8. [PMID: 16936206 DOI: 10.2337/db06-0540] [Citation(s) in RCA: 172] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Fat depots vary in size, function, and potential contribution to disease. Since fat tissue turns over throughout life, preadipocyte characteristics could contribute to this regional variation. To address whether preadipocytes from different depots are distinct, we produced preadipocyte strains from single abdominal subcutaneous, mesenteric, and omental human preadipocytes by stably expressing human telomere reverse transcriptase (hTERT). These strains could be subcultured repeatedly and retained capacity for differentiation, while primary preadipocyte adipogenesis and replication declined with subculturing. Primary omental preadipocytes, in which telomeres were longest, replicated more slowly than mesenteric or abdominal subcutaneous preadipocytes. Even after 40 population doublings, replication, abundance of the rapidly replicating preadipocyte subtype, and resistance to tumor necrosis factor alpha-induced apoptosis were highest in subcutaneous, intermediate in mesenteric, and lowest in omental hTERT-expressing strains, as in primary preadipocytes. Subcutaneous hTERT-expressing strains accumulated more lipid and expressed more adipocyte fatty acid-binding protein (aP2), peroxisome proliferator-activated receptor gamma2, and CCAAT/enhancer-binding protein alpha than omental cells, as in primary preadipocytes, while hTERT abundance was similar. Thus, despite dividing 40 population doublings, hTERT strains derived from single preadipocytes retained fat depot-specific cell dynamic characteristics, consistent with heritable processes contributing to regional variation in fat tissue function.
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Affiliation(s)
- Tamara Tchkonia
- Department of Medicine, Boston University, Boston, MA 02118, USA
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Karagiannides I, Thomou T, Tchkonia T, Pirtskhalava T, Kypreos KE, Cartwright A, Dalagiorgou G, Lash TL, Farmer SR, Timchenko NA, Kirkland JL. Increased CUG triplet repeat-binding protein-1 predisposes to impaired adipogenesis with aging. J Biol Chem 2006; 281:23025-33. [PMID: 16754681 DOI: 10.1074/jbc.m513187200] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Preadipocyte differentiation capacity declines between middle and old age. Expression of the adipogenic transcription factors, CCAAT/enhancer-binding protein (C/EBP) alpha and peroxisome proliferator-activated receptor gamma (PPARgamma), is lower in differentiating preadipocytes from old than young animals, although no age-related changes occur in C/EBPbeta mRNA, which is upstream of C/EBPalpha and PPARgamma. C/EBPbeta-liver-enriched inhibitory protein (C/EBPbeta-LIP), a truncated C/EBPbeta isoform that is a dominant inhibitor of differentiation, increases with aging in rat fat tissue and preadipocytes. CUG triplet repeat-binding protein-1 (CUGBP1) binds to C/EBPbeta mRNA, increasing C/EBPbeta-LIP translation. Abundance and nucleotide binding activity of CUGBP1 increased with aging in preadipocytes. CUGBP1 overexpression in preadipocytes from young animals increased C/EBPbeta-LIP and impaired adipogenesis. Decreasing CUGBP1 in preadipocytes from old rats by RNA interference reduced C/EBPbeta-LIP abundance and promoted adipogenesis. Tumor necrosis factor-alpha, levels of which are elevated in fat tissue with aging, increased CUGBP1 protein, CUGBP1 binding activity, and C/EBPbeta-LIP in preadipocytes from young rats. Thus, CUGBP1 contributes to regulation of adipogenesis in primary preadipocytes and is responsive to tumor necrosis factor-alpha. With aging, preadipocyte CUGBP1 abundance and activity increases, resulting in enhanced translation of the C/EBPbeta-LIP isoform, thereby blocking effects of adipogenic transcription factors, predisposing preadipocytes from old animals to resist adipogenesis. Altered translational processing, possibly related to changes in cytokine milieu and activation of stress responses, may contribute to changes in progenitor differentiation and tissue function with aging.
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