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Harada N, Kubo K, Onishi T, Kitakaze T, Goto T, Inui H, Yamaji R. Androgen receptor suppresses β-adrenoceptor-mediated CREB activation and thermogenesis in brown adipose tissue of male mice. J Biol Chem 2022; 298:102619. [PMID: 36272644 DOI: 10.1016/j.jbc.2022.102619] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Revised: 10/13/2022] [Accepted: 10/14/2022] [Indexed: 11/07/2022] Open
Abstract
Thermoregulation is a process by which core body temperature is maintained in mammals. Males typically have a lower body temperature than females. However, the effects of androgens, which show higher levels in males, on adrenergic receptor-mediated thermogenesis remain unclear. Here, we demonstrate that androgen-androgen receptor (AR) signaling suppresses the β-adrenergic agonist-induced rise of core body temperature using castrated and AR knockout (ARKO) male mice. Furthermore, in vitro mechanistic studies show that activated AR inhibits cAMP response element (CRE)-mediated transcription by suppressing cAMP response element-binding protein (CREB) phosphorylation. The elevation of body temperature induced by the β-adrenergic agonist CL316243 was higher in ARKO and castrated mice than in the control mice. Similarly, CL316243 induced a greater increase in Uncoupling protein 1 (Ucp1) expression and CREB phosphorylation in the brown adipose tissue of ARKO mice than in that of controls. We determined that activation of AR by dihydrotestosterone suppressed β3-agonist- or forskolin-induced CRE-mediated transcription, which was prevented by AR antagonist. AR activation also suppressed CREB phosphorylation induced by forskolin. Moreover, we found AR nuclear localization, but not transcriptional activity, was necessary for the suppression of CRE-mediated transcription. Finally, modified mammalian two-hybrid and immunoprecipitation analyses suggest nuclear AR and CREB form a protein complex both in the presence and absence of dihydrotestosterone and forskolin. These results suggest androgen-AR signaling suppresses β-adrenoceptor-induced UCP1-mediated brown adipose tissue thermogenesis by suppressing CREB phosphorylation, presumably owing to a protein complex with AR and CREB. This mechanism explains sexual differences in body temperature, at least partially.
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Queathem ED, Welly RJ, Clart LM, Rowles CC, Timmons H, Fitzgerald M, Eichen PA, Lubahn DB, Vieira-Potter VJ. White Adipose Tissue Depots Respond to Chronic Beta-3 Adrenergic Receptor Activation in a Sexually Dimorphic and Depot Divergent Manner. Cells 2021; 10:3453. [PMID: 34943961 DOI: 10.3390/cells10123453] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 11/28/2021] [Accepted: 11/30/2021] [Indexed: 12/24/2022] Open
Abstract
Beta-3 adrenergic receptor activation via exercise or CL316,243 (CL) induces white adipose tissue (WAT) browning, improves glucose tolerance, and reduces visceral adiposity. Our aim was to determine if sex or adipose tissue depot differences exist in response to CL. Daily CL injections were administered to diet-induced obese male and female mice for two weeks, creating four groups: male control, male CL, female control, and female CL. These groups were compared to determine the main and interaction effects of sex (S), CL treatment (T), and WAT depot (D). Glucose tolerance, body composition, and energy intake and expenditure were assessed, along with perigonadal (PGAT) and subcutaneous (SQAT) WAT gene and protein expression. CL consistently improved glucose tolerance and body composition. Female PGAT had greater protein expression of the mitochondrial uncoupling protein 1 (UCP1), while SQAT (S, p < 0.001) was more responsive to CL in increasing UCP1 (S×T, p = 0.011) and the mitochondrial biogenesis induction protein, PPARγ coactivator 1α (PGC1α) (S×T, p = 0.026). Females also displayed greater mitochondrial OXPHOS (S, p < 0.05) and adiponectin protein content (S, p < 0.05). On the other hand, male SQAT was more responsive to CL in increasing protein levels of PGC1α (S×T, p = 0.046) and adiponectin (S, p < 0.05). In both depots and in both sexes, CL significantly increased estrogen receptor beta (ERβ) and glucose-related protein 75 (GRP75) protein content (T, p < 0.05). Thus, CL improves systemic and adipose tissue-specific metabolism in both sexes; however, sex differences exist in the WAT-specific effects of CL. Furthermore, across sexes and depots, CL affects estrogen signaling by upregulating ERβ.
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Kuo CH, Harris MB, Jensen J, Alkhatib A, Ivy JL. Editorial: Possible Mechanisms to Explain Abdominal Fat Loss Effect of Exercise Training Other Than Fatty Acid Oxidation. Front Physiol 2021; 12:789463. [PMID: 34867489 PMCID: PMC8638619 DOI: 10.3389/fphys.2021.789463] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 10/19/2021] [Indexed: 11/19/2022] Open
Affiliation(s)
- Chia-Hua Kuo
- Laboratory of Exercise Biochemistry, College of Kinesiology, University of Taipei, Taipei, Taiwan
| | - M Brennan Harris
- Department of Health Sciences, College of William and Mary, Williamsburg, VA, United States
| | - Jørgen Jensen
- Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Ahmad Alkhatib
- Laboratory of Exercise Biochemistry, University of Taipei, Taipei, Taiwan.,School of Health and Life Sciences, Teesside University, Middlesbrough, United Kingdom
| | - John L Ivy
- Exercise Physiology and Metabolism Laboratory, Department of Kinesiology and Health Education, University of Texas at Austin, Austin, TX, United States
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Anoop S, Krakauer J, Krakauer N, Misra A. A Body shape index significantly predicts MRI-defined abdominal adipose tissue depots in non-obese Asian Indians with type 2 diabetes mellitus. BMJ Open Diabetes Res Care 2020; 8:8/1/e001324. [PMID: 33051279 PMCID: PMC7554502 DOI: 10.1136/bmjdrc-2020-001324] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 07/10/2020] [Accepted: 07/13/2020] [Indexed: 12/27/2022] Open
Abstract
INTRODUCTION We aimed to determine the correlations of volumes of subcutaneous abdominal adipose tissue (SCAT) (anterior, posterior, superficial and deep), total SCAT, intraperitoneal adipose tissue, retroperitoneal abdominal adipose tissue (RPAT), total intra-abdominal adipose tissue (IAAT), pancreatic volume, liver span, total body fat (TBF) and truncal fat mass (TFM) with anthropometric indices, viz., A Body Shape Index (ABSI), Hip Index, their Z scores and Anthropometric Risk Index in non-obese (body mass index (BMI) <25 kg/m2) Asian Indians with type 2 diabetes mellitus (T2DM). RESEARCH DESIGN AND METHODS Non-obese patients with T2DM (cases; n, 85) and BMI-matched, healthy subjects (controls; n, 38) underwent anthropometry, dual energy X ray absorptiometry (DXA) for estimation of TBF, TFM and 1.5 T MRI for estimation of volumes of abdominal adipose tissue depots, pancreas and liver span. Spearman's correlation analysis and Receiver Operator Characteristic curve analysis were applied. RESULTS The Z score of ABSI (Z_ABSI) showed significantly positive correlation with volumes of all depots of abdominal SCAT, total IAAT and RPAT in cases. Area under the curve for Z_ABSI (0.87) showed higher sensitivity: 82.0 %, specificity: 81.5 %, at a predictive cut-off value of 0.49 for abdominal adiposity. CONCLUSION In non-obese Asian Indians with T2DM, the Z_ABSI showed significant correlation with IAAT and SCAT and higher predictive accuracy for abdominal adiposity. HIGHLIGHTS OF THE STUDY This is the first MRI-based study in the context of ABSI in non-obese (BMI <25 kg/m2) Asian Indians with T2DM. Findings indicate that Z_ABSI has high predictive accuracy for abdominal adiposity in non-obese Asian Indians. The Z_ABSI index showed significantly positive correlation with volumes of adipose tissue depots, viz., abdominal SCAT, total IAAT and RPAT in cases.
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Affiliation(s)
- Shajith Anoop
- Centre of Nutrition & Metabolic Research (C-NET), National Diabetes, Obesity and Cholesterol Foundation (N-DOC), Safdarjung Development Area, New Delhi, India
- Diabetes Foundation (India), Safdarjung Development Area, New Delhi, India
- Centre of Excellence for Diabetes, Metabolic Diseases and Endocrinology, Fortis C-DOC Hospital, New Delhi, India
- National Diabetes, Obesity and Cholesterol Foundation, New Delhi, India
| | - Jesse Krakauer
- Metro Detroit Diabetes and Endocrinology, Southfield, Michigan, USA
| | - Nir Krakauer
- Department of Civil Engineering, The City College of New York, New York, New York, USA
| | - Anoop Misra
- Centre of Nutrition & Metabolic Research (C-NET), National Diabetes, Obesity and Cholesterol Foundation (N-DOC), Safdarjung Development Area, New Delhi, India
- Diabetes Foundation (India), Safdarjung Development Area, New Delhi, India
- Centre of Excellence for Diabetes, Metabolic Diseases and Endocrinology, Fortis C-DOC Hospital, New Delhi, India
- National Diabetes, Obesity and Cholesterol Foundation, New Delhi, India
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Honkala SM, Motiani P, Kivelä R, Hemanthakumar KA, Tolvanen E, Motiani KK, Eskelinen JJ, Virtanen KA, Kemppainen J, Heiskanen MA, Löyttyniemi E, Nuutila P, Kalliokoski KK, Hannukainen JC. Exercise training improves adipose tissue metabolism and vasculature regardless of baseline glucose tolerance and sex. BMJ Open Diabetes Res Care 2020; 8:8/1/e000830. [PMID: 32816872 PMCID: PMC7437884 DOI: 10.1136/bmjdrc-2019-000830] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 05/08/2020] [Accepted: 06/10/2020] [Indexed: 12/13/2022] Open
Abstract
INTRODUCTION We investigated the effects of a supervised progressive sprint interval training (SIT) and moderate-intensity continuous training (MICT) on adipocyte morphology and adipose tissue metabolism and function; we also tested whether the responses were similar regardless of baseline glucose tolerance and sex. RESEARCH DESIGN AND METHODS 26 insulin-resistant (IR) and 28 healthy participants were randomized into 2-week-long SIT (4-6×30 s at maximum effort) and MICT (40-60 min at 60% of maximal aerobic capacity (VO2peak)). Insulin-stimulated glucose uptake and fasting-free fatty acid uptake in visceral adipose tissue (VAT), abdominal and femoral subcutaneous adipose tissues (SATs) were quantified with positron emission tomography. Abdominal SAT biopsies were collected to determine adipocyte morphology, gene expression markers of lipolysis, glucose and lipid metabolism and inflammation. RESULTS Training increased glucose uptake in VAT (p<0.001) and femoral SAT (p<0.001) and decreased fatty acid uptake in VAT (p=0.01) irrespective of baseline glucose tolerance and sex. In IR participants, training increased adipose tissue vasculature and decreased CD36 and ANGPTL4 gene expression in abdominal SAT. SIT was superior in increasing VO2peak and VAT glucose uptake in the IR group, whereas MICT reduced VAT fatty acid uptake more than SIT. CONCLUSIONS Short-term training improves adipose tissue metabolism both in healthy and IR participants independently of the sex. Adipose tissue angiogenesis and gene expression was only significantly affected in IR participants.
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Affiliation(s)
| | | | - Riikka Kivelä
- Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | | | - Erik Tolvanen
- Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | | | | | | | | | | | | | - Pirjo Nuutila
- Turku PET Centre, University of Turku, Turku, Finland
- Turku PET Centre, Turku University Hospital, Turku, Finland
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Karis P, Jaakson H, Ling K, Bruckmaier RM, Gross JJ, Pärn P, Kaart T, Ots M. Body condition and insulin resistance interactions with periparturient gene expression in adipose tissue and lipid metabolism in dairy cows. J Dairy Sci 2020; 103:3708-3718. [PMID: 32008773 DOI: 10.3168/jds.2019-17373] [Citation(s) in RCA: 10] [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] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 12/02/2019] [Indexed: 12/19/2022]
Abstract
Adipose tissue plays an important role in a cow's ability to adapt to the metabolic demands of lactation, because of its central involvement in energy metabolism and immunity. High adiposity and adipose tissue resistance to insulin are associated with excessive lipid mobilization. We hypothesized that the response to a glucose challenge differs between cows of different body condition 21 d before and after calving and that the responses are explainable by gene expression in subcutaneous adipose tissue (SAT). In addition, we aimed to investigate insulin resistance with gene expression in SAT and lipid mobilization around parturition. Multiparous Holstein cows were grouped according to body conditions score (BCS) 4 wk before calving, as follows: BCS ≤ 3.0 = thin (T, n = 14); BCS 3.25 to 3.5 = optimal (O, n = 14); BCS ≥ 3.75 = over-conditioned (OC, n = 14). We collected SAT on d -21 and d 21 relative to calving. A reverse-transcriptase quantitative (RT-q)PCR was used to measure gene expression related to lipid metabolism. One hour after the collection of adipose tissue, an intravenous glucose tolerance test was carried out, with administration of 0.15 g of glucose per kg of body weight (with a 40% glucose solution). Once weekly from the first week before calving to the third week after calving, a blood sample was taken. The transition to lactation was associated with intensified release of energy stored in adipose tissue, a decrease in the lipogenic genes lipoprotein lipase (LPL) and diacylglycerol O-acyltransferase 2 (DGAT2), and an increase in the lipolytic gene hormone-sensitive lipase (LIPE). On d -21, compared with T cows, OC cows had lower mRNA abundance of LPL and DGAT2, and the latency of fatty acid response after glucose infusion was also longer (8.5 vs. 23.3 min) in OC cows. Cows with higher insulin area under the curve on d -21 had concurrently lower LPL and DGAT2 gene expression and greater concentration of fatty acids on d -7, d 7, and d 14. In conclusion, high adiposity prepartum lowers the whole-body lipid metabolism response to insulin and causes reduced expression of lipogenic genes in SAT 3 weeks before calving. In addition, more pronounced insulin release after glucose infusion on d -21 is related to higher lipid mobilization around calving, indicating an insulin-resistant state, and is associated with lower expression of lipogenic genes in SAT.
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Affiliation(s)
- P Karis
- Chair of Animal Nutrition, Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, 51006 Tartu, Estonia.
| | - H Jaakson
- Chair of Animal Nutrition, Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, 51006 Tartu, Estonia
| | - K Ling
- Chair of Animal Nutrition, Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, 51006 Tartu, Estonia
| | - R M Bruckmaier
- Veterinary Physiology, Vetsuisse Faculty, University of Bern, CH-3001, Switzerland
| | - J J Gross
- Veterinary Physiology, Vetsuisse Faculty, University of Bern, CH-3001, Switzerland
| | - P Pärn
- Chair of Animal Breeding and Biotechnology, Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, 51014 Tartu, Estonia
| | - T Kaart
- Chair of Animal Breeding and Biotechnology, Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, 51014 Tartu, Estonia
| | - M Ots
- Chair of Animal Nutrition, Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, 51006 Tartu, Estonia
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7
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Srivastava RK, Moliner A, Lee ES, Nickles E, Sim E, Liu C, Schwarz H, Ibáñez CF. CD137 negatively affects "browning" of white adipose tissue during cold exposure. J Biol Chem 2020; 295:2034-2042. [PMID: 31919095 DOI: 10.1074/jbc.ac119.011795] [Citation(s) in RCA: 10] [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] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 12/20/2019] [Indexed: 12/17/2022] Open
Abstract
Prolonged cold exposure stimulates the formation of brownlike adipocytes expressing UCP1 (uncoupling-protein-1) in subcutaneous white adipose tissue which, together with classical brown adipose tissue, contributes to maintaining body temperature in mammals through nonshivering thermogenesis. The mechanisms that regulate the formation of these cells, alternatively called beige or brite adipocytes, are incompletely understood. Here we report that mice lacking CD137, a cell surface protein used in several studies as a marker for beige adipocytes, showed elevated levels of thermogenic markers, including UCP1, increased numbers of beige adipocyte precursors, and expanded UCP1-expressing cell clusters in inguinal white adipose tissue after chronic cold exposure. CD137 knockout mice also showed enhanced cold resistance. These results indicate that CD137 functions as a negative regulator of "browning" in white adipose tissue and call into question the use of this protein as a functional marker for beige adipocytes.
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Affiliation(s)
- Raj Kamal Srivastava
- Department of Physiology, National University of Singapore, Singapore 117597, Singapore; Life Sciences Institute, National University of Singapore, Singapore 117456, Singapore
| | - Annalena Moliner
- Life Sciences Institute, National University of Singapore, Singapore 117456, Singapore; Department of Neuroscience, Karolinska Institute, Stockholm 17177, Sweden
| | - Ee-Soo Lee
- Department of Physiology, National University of Singapore, Singapore 117597, Singapore; Life Sciences Institute, National University of Singapore, Singapore 117456, Singapore
| | - Emily Nickles
- Department of Physiology, National University of Singapore, Singapore 117597, Singapore; Life Sciences Institute, National University of Singapore, Singapore 117456, Singapore
| | - Eunice Sim
- Department of Physiology, National University of Singapore, Singapore 117597, Singapore; Life Sciences Institute, National University of Singapore, Singapore 117456, Singapore
| | - Chang Liu
- Department of Physiology, National University of Singapore, Singapore 117597, Singapore; Life Sciences Institute, National University of Singapore, Singapore 117456, Singapore
| | - Herbert Schwarz
- Department of Physiology, National University of Singapore, Singapore 117597, Singapore; Life Sciences Institute, National University of Singapore, Singapore 117456, Singapore
| | - Carlos F Ibáñez
- Department of Physiology, National University of Singapore, Singapore 117597, Singapore; Life Sciences Institute, National University of Singapore, Singapore 117456, Singapore; Department of Neuroscience, Karolinska Institute, Stockholm 17177, Sweden; Stellenbosch Institute for Advanced Study, Wallenberg Research Centre at Stellenbosch University, Stellenbosch 7600, South Africa.
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8
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Xu Y, Du X, Turner N, Brown AJ, Yang H. Enhanced acyl-CoA:cholesterol acyltransferase activity increases cholesterol levels on the lipid droplet surface and impairs adipocyte function. J Biol Chem 2019; 294:19306-19321. [PMID: 31727739 DOI: 10.1074/jbc.ra119.011160] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [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: 09/27/2019] [Revised: 11/11/2019] [Indexed: 01/21/2023] Open
Abstract
Cholesterol plays essential structural and signaling roles in mammalian cells, but too much cholesterol can cause cytotoxicity. Acyl-CoA:cholesterol acyltransferases 1 and 2 (ACAT1/2) convert cholesterol into its storage form, cholesteryl esters, regulating a key step in cellular cholesterol homeostasis. Adipose tissue can store >50% of whole-body cholesterol. Interestingly, however, almost no ACAT activity is present in adipose tissue, and most adipose cholesterol is stored in its free form. We therefore hypothesized that increased cholesterol esterification may have detrimental effects on adipose tissue function. Here, using several approaches, including protein overexpression, quantitative RT-PCR, immunofluorescence, and various biochemical assays, we found that ACAT1 expression is significantly increased in the adipose tissue of the ob/ob mice. We further demonstrated that ACAT1/2 overexpression partially inhibited the differentiation of 3T3-L1 preadipocytes. In mature adipocytes, increased ACAT activity reduced the size of lipid droplets (LDs) and inhibited lipolysis and insulin signaling. Paradoxically, the amount of free cholesterol increased on the surface of LDs in ACAT1/2-overexpressing adipocytes, accompanied by increased LD localization of caveolin-1. Moreover, cholesterol depletion in adipocytes by treating the cells with cholesterol-deficient media or β-cyclodextrins induced changes in cholesterol distribution that were similar to those caused by ACAT1/2 overexpression. Our results suggest that ACAT1/2 overexpression increases the level of free cholesterol on the LD surface, thereby impeding adipocyte function. These findings provide detailed insights into the role of free cholesterol in LD and adipocyte function and suggest that ACAT inhibitors have potential utility for managing disorders associated with extreme obesity.
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Affiliation(s)
- Yanqing Xu
- School of Biotechnology and Biomolecular Sciences, the University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Ximing Du
- School of Biotechnology and Biomolecular Sciences, the University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Nigel Turner
- School of Medical Sciences, the University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Andrew J Brown
- School of Biotechnology and Biomolecular Sciences, the University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Hongyuan Yang
- School of Biotechnology and Biomolecular Sciences, the University of New South Wales, Sydney, New South Wales 2052, Australia
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9
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Sparks R, Lui A, Bader D, Patel R, Murr M, Guida W, Fratti R, Patel NA. A specific small-molecule inhibitor of protein kinase CδI activity improves metabolic dysfunction in human adipocytes from obese individuals. J Biol Chem 2019; 294:14896-14910. [PMID: 31413114 DOI: 10.1074/jbc.ra119.008777] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [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: 04/06/2019] [Revised: 07/11/2019] [Indexed: 12/17/2022] Open
Abstract
The metabolic consequences and sequelae of obesity promote life-threatening morbidities. PKCδI is an important elicitor of inflammation and apoptosis in adipocytes. Here we report increased PKCδI activation via release of its catalytic domain concurrent with increased expression of proinflammatory cytokines in adipocytes from obese individuals. Using a screening strategy of dual recognition of PKCδI isozymes and a caspase-3 binding site on the PKCδI hinge domain with Schrödinger software and molecular dynamics simulations, we identified NP627, an organic small-molecule inhibitor of PKCδI. Characterization of NP627 by surface plasmon resonance (SPR) revealed that PKCδI and NP627 interact with each other with high affinity and specificity, SPR kinetics revealed that NP627 disrupts caspase-3 binding to PKCδI, and in vitro kinase assays demonstrated that NP627 specifically inhibits PKCδI activity. The SPR results also indicated that NP627 affects macromolecular interactions between protein surfaces. Of note, release of the PKCδI catalytic fragment was sufficient to induce apoptosis and inflammation in adipocytes. NP627 treatment of adipocytes from obese individuals significantly inhibited PKCδI catalytic fragment release, decreased inflammation and apoptosis, and significantly improved mitochondrial metabolism. These results indicate that PKCδI is a robust candidate for targeted interventions to manage obesity-associated chronic inflammatory diseases. We propose that NP627 may also be used in other biological systems to better understand the impact of caspase-3-mediated activation of kinase activity.
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Affiliation(s)
- Robert Sparks
- Department of Biochemistry, University of Illinois, Urbana-Champaign, Illinois 61801
| | - Ashley Lui
- Department of Molecular Medicine, University of South Florida, Tampa, Florida 33612
| | - Deena Bader
- James A. Haley Veterans Hospital, Tampa, Florida 33612
| | - Rekha Patel
- Department of Chemistry, University of South Florida, Tampa, Florida 33612
| | - Michel Murr
- Surgery Department, University of Central Florida, Orlando, Florida 32816.,Bariatric and Metabolic Institute, AdventHealth, Tampa, Florida 33612
| | - Wayne Guida
- Department of Chemistry, University of South Florida, Tampa, Florida 33612
| | - Rutilio Fratti
- Department of Biochemistry, University of Illinois, Urbana-Champaign, Illinois 61801
| | - Niketa A Patel
- Department of Molecular Medicine, University of South Florida, Tampa, Florida 33612 .,James A. Haley Veterans Hospital, Tampa, Florida 33612
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Kim SP, Da H, Li Z, Kushwaha P, Beil C, Mei L, Xiong WC, Wolfgang MJ, Clemens TL, Riddle RC. Lrp4 expression by adipocytes and osteoblasts differentially impacts sclerostin's endocrine effects on body composition and glucose metabolism. J Biol Chem 2019; 294:6899-6911. [PMID: 30842262 DOI: 10.1074/jbc.ra118.006769] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [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: 11/17/2018] [Revised: 02/23/2019] [Indexed: 01/10/2023] Open
Abstract
Sclerostin exerts profound local control over bone acquisition and also mediates endocrine communication between fat and bone. In bone, sclerostin's anti-osteoanabolic activity is enhanced by low-density lipoprotein receptor-related protein 4 (Lrp4), which facilitates its interaction with the Lrp5 and Lrp6 Wnt co-receptors. To determine whether Lrp4 similarly affects sclerostin's endocrine function, we examined body composition as well as glucose and fatty acid metabolism in mice rendered deficient of Lrp4 in the adipocyte (AdΔLrp4) or the osteoblast (ObΔLrp4). AdΔLrp4 mice exhibit a reduction in adipocyte hypertrophy and improved glucose and lipid homeostasis, marked by increased glucose and insulin tolerance and reduced serum fatty acids, and mirror the effect of sclerostin deficiency on whole-body metabolism. Indeed, epistasis studies place adipocyte-expressed Lrp4 and sclerostin in the same genetic cascade that regulates adipocyte function. Intriguingly, ObΔLrp4 mice, which exhibit dramatic increases in serum sclerostin, accumulate body fat and develop impairments in glucose tolerance and insulin sensitivity despite development of a high bone mass phenotype. These data indicate that expression of Lrp4 by both the adipocyte and osteoblast is required for normal sclerostin endocrine function and that the impact of sclerostin deficiency on adipocyte physiology is distinct from the effect on osteoblast function.
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Affiliation(s)
| | - Hao Da
- From the Departments of Orthopedic Surgery and
| | - Zhu Li
- From the Departments of Orthopedic Surgery and
| | | | - Conor Beil
- From the Departments of Orthopedic Surgery and
| | - Lin Mei
- the Department of Neuroscience, Case Western Reserve University Medical School, Cleveland, Ohio 44106, and
| | - Wen-Cheng Xiong
- the Department of Neuroscience, Case Western Reserve University Medical School, Cleveland, Ohio 44106, and
| | - Michael J Wolfgang
- Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Thomas L Clemens
- From the Departments of Orthopedic Surgery and.,the Baltimore Veterans Affairs Medical Center, Baltimore, Maryland 21201
| | - Ryan C Riddle
- From the Departments of Orthopedic Surgery and .,the Baltimore Veterans Affairs Medical Center, Baltimore, Maryland 21201
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11
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McCormick CD, Waters HN, Bezrukov L, Taginya R, Parikh V, Onyekaba GI, Levine JA, Demidowich AP, Yanovski JA, Blank PS, Zimmerberg J. Subcutaneous adipose tissue imaging of human obesity reveals two types of adipocyte membranes: Insulin-responsive and -nonresponsive. J Biol Chem 2018; 293:14249-14259. [PMID: 30006347 DOI: 10.1074/jbc.ra118.003751] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [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: 04/30/2018] [Revised: 06/28/2018] [Indexed: 11/06/2022] Open
Abstract
In adipose tissue, resistance to insulin's ability to increase glucose uptake can be induced by multiple factors, including obesity. Impaired insulin action may take place at different spatial loci at the cellular or subcellular level. To begin to understand the spatial response to insulin in human subcutaneous adipose tissue (hSAT), we developed a quantitative imaging method for activation of a major signaling node in the glucoregulatory insulin signaling pathway. After treatment with insulin or control media, biopsied tissues were immunostained for Akt phosphorylation at Thr-308/9 (pAkt) and then imaged by confocal fluorescence microscopy automated to collect a large grid of high resolution fields. In hSAT from 40 men and women with obesity, substantial heterogeneity of pAkt densities in adipocyte membranes were quantified in each image mosaic using a spatial unit of at least twice the size of the point spread function. Statistical analysis of the distribution of pAkt spatial units was best fit as the weighted sum of two separate distributions, corresponding to either a low or high pAkt density. A "high pAkt fraction" metric was calculated from the fraction of high pAkt distributed units over the total units. Importantly, upon insulin stimulation, tissues from the same biopsy showed either a minimal or a substantial change in the high pAkt fraction. Further supporting a two-state response to insulin stimulation, subjects with similar insulin sensitivity indices are also segregated into either of two clusters identified by the amount of membrane-localized pAkt.
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Affiliation(s)
| | | | | | | | - Viraj Parikh
- Section on Growth and Obesity, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892
| | - Ginikanwa I Onyekaba
- Section on Growth and Obesity, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892
| | - Jordan A Levine
- Section on Growth and Obesity, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892
| | - Andrew P Demidowich
- Section on Growth and Obesity, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892
| | - Jack A Yanovski
- Section on Growth and Obesity, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892
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12
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Plaza A, Merino B, Cano V, Domínguez G, Pérez-Castells J, Fernández-Alfonso MS, Sengenès C, Chowen JA, Ruiz-Gayo M. Cholecystokinin is involved in triglyceride fatty acid uptake by rat adipose tissue. J Endocrinol 2018; 236:137-150. [PMID: 29339381 DOI: 10.1530/joe-17-0580] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Accepted: 01/16/2018] [Indexed: 11/08/2022]
Abstract
The incorporation of plasma triglyceride (TG) fatty acids to white adipose tissue (WAT) depends on lipoprotein lipase (LPL), which is regulated by angiopoietin-like protein-4 (ANGPTL-4), an unfolding molecular chaperone that converts active LPL dimers into inactive monomers. The production of ANGPTL-4 is promoted by fasting and repressed by feeding. We hypothesized that the postprandial hormone cholecystokinin (CCK) facilitates the storage of dietary TG fatty acids in WAT by regulating the activity of the LPL/ANGPTL-4 axis and that it does so by acting directly on CCK receptors in adipocytes. We report that administration of CCK-8 (a bioactive fragment of CCK) to rats: (i) reduces plasma ANGTPL-4 levels; (ii) represses Angptl-4 expression in WAT and (iii) simultaneously enhances LPL activity in this tissue without inducing Lpl expression. In vivo CCK-8 effects are specifically antagonized by the CCK-2 receptor (CCK-2R) antagonist, L-365,260. Moreover, CCK-8 downregulates Angptl-4 expression in wild-type pre-adipocytes, an effect that is not observed in engineered pre-adipocytes lacking CCK-2R. These effects have functional consequences as CCK-8 was found to promote the uptake of dietary fatty acids by WAT, as demonstrated by means of proton nuclear magnetic resonance (1H-NMR). The efficacy of acute CCK-8 administration was not reduced after chronic CCK-8 treatment. Moreover, the effects of CCK-8 on WAT were not associated to the increase of circulating insulin. Our results show that cholecystokinin promotes lipid storage in WAT by acting on adipocyte CCK-2R, suggesting a pivotal role for CCK in TG homeostasis.
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Affiliation(s)
- Adrián Plaza
- Departamento de Ciencias Farmacéuticas y de la SaludFacultad de Farmacia, Universidad San Pablo-CEU, Madrid, Spain
| | - Beatriz Merino
- Departamento de Ciencias Farmacéuticas y de la SaludFacultad de Farmacia, Universidad San Pablo-CEU, Madrid, Spain
| | - Victoria Cano
- Departamento de Ciencias Farmacéuticas y de la SaludFacultad de Farmacia, Universidad San Pablo-CEU, Madrid, Spain
| | - Gema Domínguez
- Departamento de Química y BioquímicaFacultad de Farmacia, Universidad San Pablo-CEU, Madrid, Spain
| | - Javier Pérez-Castells
- Departamento de Química y BioquímicaFacultad de Farmacia, Universidad San Pablo-CEU, Madrid, Spain
| | | | - Coralie Sengenès
- STROMALabUniversité de Toulouse, CNRS ERL5311, EFS, INP-ENVT, Inserm U1031, UPS, Toulouse, France
| | - Julie A Chowen
- Departamento de EndocrinologíaHospital Infantil Universitario Niño Jesús, Instituto de Investigación Sanitaria Princesa, CIBEROBN Instituto Carlos III, Madrid, Spain
| | - Mariano Ruiz-Gayo
- Departamento de Ciencias Farmacéuticas y de la SaludFacultad de Farmacia, Universidad San Pablo-CEU, Madrid, Spain
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13
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Chouchani ET, Kazak L, Spiegelman BM. Mitochondrial reactive oxygen species and adipose tissue thermogenesis: Bridging physiology and mechanisms. J Biol Chem 2017; 292:16810-16816. [PMID: 28842500 DOI: 10.1074/jbc.r117.789628] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Brown and beige adipose tissues can catabolize stored energy to generate heat, relying on the principal effector of thermogenesis: uncoupling protein 1 (UCP1). This unique capability could be leveraged as a therapy for metabolic disease. Numerous animal and cellular models have now demonstrated that mitochondrial reactive oxygen species (ROS) signal to support adipocyte thermogenic identity and function. Herein, we contextualize these findings within the established principles of redox signaling and mechanistic studies of UCP1 function. We provide a framework for understanding the role of mitochondrial ROS signaling in thermogenesis together with testable hypotheses for understanding mechanisms and developing therapies.
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Affiliation(s)
- Edward T Chouchani
- From the Dana-Farber Cancer Institute, Harvard Medical School and.,Department of Cell Biology, Harvard University Medical School, Boston, Massachusetts 02115
| | - Lawrence Kazak
- From the Dana-Farber Cancer Institute, Harvard Medical School and.,Department of Cell Biology, Harvard University Medical School, Boston, Massachusetts 02115
| | - Bruce M Spiegelman
- From the Dana-Farber Cancer Institute, Harvard Medical School and .,Department of Cell Biology, Harvard University Medical School, Boston, Massachusetts 02115
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14
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Chang JS, Ha K. An unexpected role for the transcriptional coactivator isoform NT-PGC-1α in the regulation of mitochondrial respiration in brown adipocytes. J Biol Chem 2017; 292:9958-9966. [PMID: 28473468 DOI: 10.1074/jbc.m117.778373] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [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: 01/25/2017] [Revised: 05/02/2017] [Indexed: 02/05/2023] Open
Abstract
Brown adipose tissue dissipates energy as heat, a process that relies on a high abundance of mitochondria and high levels of electron transport chain (ETC) complexes within these mitochondria. Two regulators of mitochondrial respiration and heat production in brown adipocytes are the transcriptional coactivator PGC-1α and its splicing isoform NT-PGC-1α, which control mitochondrial gene expression in the nucleus. Surprisingly, we found that, in brown adipocytes, some NT-PGC-1α localizes to mitochondria, whereas PGC-1α resides in the nucleus. Here we sought to investigate the role of NT-PGC-1α in brown adipocyte mitochondria. Immunocytochemistry, immunotransmission electron microscopy, and biochemical analyses indicated that NT-PGC-1α was located in the mitochondrial matrix in brown adipocytes. NT-PGC-1α was specifically enriched at the D-loop region of the mtDNA, which contains the promoters for several essential ETC complex genes, and was associated with LRP130, an activator of mitochondrial transcription. Selective expression of NT-PGC-1α and PGC-1α in PGC-1α-/- brown adipocytes similarly induced expression of nuclear DNA-encoded mitochondrial ETC genes, including the key mitochondrial transcription factor A (TFAM). Despite having comparable levels of TFAM expression, PGC-1α-/- brown adipocytes expressing NT-PGC-1α had higher expression of mtDNA-encoded ETC genes than PGC-1α-/- brown adipocytes expressing PGC-1α, suggesting a direct effect of NT-PGC-1α on mtDNA transcription. Moreover, this increase in mtDNA-encoded ETC gene expression was associated with enhanced respiration in NT-PGC-1α-expressing PGC-1α-/- brown adipocytes. Our findings reveal a previously unappreciated and isoform-specific role for NT-PGC-1α in the regulation of mitochondrial transcription in brown adipocytes and provide new insight into the transcriptional control of mitochondrial respiration.
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Affiliation(s)
- Ji Suk Chang
- From the Laboratory of Gene Regulation and Metabolism, Pennington Biomedical Research Center, Baton Rouge, Louisiana 70808
| | - Kyoungsoo Ha
- From the Laboratory of Gene Regulation and Metabolism, Pennington Biomedical Research Center, Baton Rouge, Louisiana 70808
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15
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Nagao H, Nishizawa H, Bamba T, Nakayama Y, Isozumi N, Nagamori S, Kanai Y, Tanaka Y, Kita S, Fukuda S, Funahashi T, Maeda N, Fukusaki E, Shimomura I. Increased Dynamics of Tricarboxylic Acid Cycle and Glutamate Synthesis in Obese Adipose Tissue: IN VIVO METABOLIC TURNOVER ANALYSIS. J Biol Chem 2017; 292:4469-4483. [PMID: 28119455 DOI: 10.1074/jbc.m116.770172] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [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: 11/29/2016] [Revised: 01/06/2017] [Indexed: 01/20/2023] Open
Abstract
Obesity is closely associated with various metabolic disorders. However, little is known about abnormalities in the metabolic change of obese adipose tissue. Here we use static metabolic analysis and in vivo metabolic turnover analysis to assess metabolic dynamics in obese mice. The static metabolic analyses showed that glutamate and constitutive metabolites of the TCA cycle were increased in the white adipose tissue (WAT) of ob/ob and diet-induced obesity mice but not in the liver or skeletal muscle of these obese mice. Moreover, in vivo metabolic turnover analyses demonstrated that these glucose-derived metabolites were dynamically and specifically produced in obese WAT compared with lean WAT. Glutamate rise in obese WAT was associated with down-regulation of glutamate aspartate transporter (GLAST), a major glutamate transporter for adipocytes, and low uptake of glutamate into adipose tissue. In adipocytes, glutamate treatment reduced adiponectin secretion and insulin-mediated glucose uptake and phosphorylation of Akt. These data suggest that a high intra-adipocyte glutamate level potentially relates to adipocyte dysfunction in obesity. This study provides novel insights into metabolic dysfunction in obesity through comprehensive application of in vivo metabolic turnover analysis in two obese animal models.
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Affiliation(s)
| | | | - Takeshi Bamba
- Department of Biotechnology, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
| | - Yasumune Nakayama
- Department of Biotechnology, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
| | | | | | | | | | - Shunbun Kita
- From the Departments of Metabolic Medicine.,Metabolism and Atherosclerosis, Graduate School of Medicine, and
| | | | - Tohru Funahashi
- From the Departments of Metabolic Medicine.,Metabolism and Atherosclerosis, Graduate School of Medicine, and
| | - Norikazu Maeda
- From the Departments of Metabolic Medicine.,Metabolism and Atherosclerosis, Graduate School of Medicine, and
| | - Eiichiro Fukusaki
- Department of Biotechnology, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
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16
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Koh EH, Chen Y, Bader DA, Hamilton MP, He B, York B, Kajimura S, McGuire SE, Hartig SM. Mitochondrial Activity in Human White Adipocytes Is Regulated by the Ubiquitin Carrier Protein 9/microRNA-30a Axis. J Biol Chem 2016; 291:24747-24755. [PMID: 27758866 DOI: 10.1074/jbc.m116.749408] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [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: 07/29/2016] [Revised: 09/30/2016] [Indexed: 11/06/2022] Open
Abstract
The acquisition of beige adipocyte features by white fat cells corresponds to protection against obesity-induced metabolic diseases in humans and animal models of type 2 diabetes. In adipose tissue, expression of the E2 small ubiquitin-like modifier ligase ubiquitin carrier protein 9 (Ubc9) is positively correlated with markers of insulin resistance and corresponds with impaired browning of human white adipocytes. However, the molecular regulation of Ubc9 expression in adipocytes and other cells remains unclear. In this study, we demonstrate that the mRNA and protein expression of Ubc9 are regulated by the microRNA miRNA-30a (miR-30a) in human subcutaneous adipocytes. Ubc9 and miR-30a exhibit inverse expression in adipose tissue, with miR-30a robustly elevated in brown fat. Depletion of Ubc9 by siRNA or enforced expression of a miR-30a mimic augments mitochondrial volume and respiration in human white adipocytes, reflecting features of brown fat cells. Furthermore, Ubc9 depletion induces a brown fat gene program in human subcutaneous adipocytes. Induction of the beige-selective gene program corresponds to stabilization of the PR domain-containing 16 (PRDM16) protein, an obligate transcriptional regulator of the brown/beige fat metabolic program in white adipocytes that interacts with Ubc9. Taken together, our data demonstrate a previously unappreciated molecular axis that controls browning of human white adipocytes.
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Affiliation(s)
- Eun Hee Koh
- From the Departments of Molecular and Cellular Biology and; the Department of Internal Medicine, Asan Medical Center, Seoul 138-736, Republic of Korea
| | - Yong Chen
- the Diabetes Center and Department of Cell and Tissue Biology, University of California, San Francisco, California 94143, and
| | - David A Bader
- From the Departments of Molecular and Cellular Biology and
| | | | - Bin He
- From the Departments of Molecular and Cellular Biology and; Medicine, Division of Hematology and Oncology, Baylor College of Medicine, Houston, Texas 77030
| | - Brian York
- From the Departments of Molecular and Cellular Biology and
| | - Shingo Kajimura
- the Diabetes Center and Department of Cell and Tissue Biology, University of California, San Francisco, California 94143, and
| | - Sean E McGuire
- From the Departments of Molecular and Cellular Biology and; the Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas 77030
| | - Sean M Hartig
- From the Departments of Molecular and Cellular Biology and.
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17
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Kim J, Okla M, Erickson A, Carr T, Natarajan SK, Chung S. Eicosapentaenoic Acid Potentiates Brown Thermogenesis through FFAR4-dependent Up-regulation of miR-30b and miR-378. J Biol Chem 2016; 291:20551-62. [PMID: 27489163 DOI: 10.1074/jbc.m116.721480] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Indexed: 01/25/2023] Open
Abstract
Emerging evidence suggests that n-3 polyunsaturated fatty acids (PUFA) promote brown adipose tissue thermogenesis. However, the underlying mechanisms remain elusive. Here, we hypothesize that n-3 PUFA promotes brown adipogenesis by modulating miRNAs. To test this hypothesis, murine brown preadipocytes were induced to differentiate the fatty acids of palmitic, oleate, or eicosapentaenoic acid (EPA). The increases of brown-specific signature genes and oxygen consumption rate by EPA were concurrent with up-regulation of miR-30b and 378 but not by oleate or palmitic acid. Next, we hypothesize that free fatty acid receptor 4 (Ffar4), a functional receptor for n-3 PUFA, modulates miR-30b and 378. Treatment of Ffar4 agonist (GW9508) recapitulated the thermogenic activation of EPA by increasing oxygen consumption rate, brown-specific marker genes, and miR-30b and 378, which were abrogated in Ffar4-silenced cells. Intriguingly, addition of the miR-30b mimic was unable to restore EPA-induced Ucp1 expression in Ffar4-depleted cells, implicating that Ffar4 signaling activity is required for up-regulating the brown adipogenic program. Moreover, blockage of miR-30b or 378 by locked nucleic acid inhibitors significantly attenuated Ffar4 as well as brown-specific signature gene expression, suggesting the signaling interplay between Ffar4 and miR-30b/378. The association between miR-30b/378 and brown thermogenesis was also confirmed in fish oil-fed C57/BL6 mice. Interestingly, the Ffar4 agonism-mediated signaling axis of Ffar4-miR-30b/378-Ucp1 was linked with an elevation of cAMP in brown adipocytes, similar to cold-exposed or fish oil-fed brown fat. Taken together, our work identifies a novel function of Ffar4 in modulating brown adipogenesis partly through a mechanism involving cAMP activation and up-regulation of miR-30b and miR-378.
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Affiliation(s)
- Jiyoung Kim
- From the Department of Nutrition and Health Sciences, the University of Nebraska, Lincoln, Nebraska 68583
| | - Meshail Okla
- From the Department of Nutrition and Health Sciences, the University of Nebraska, Lincoln, Nebraska 68583
| | - Anjeza Erickson
- From the Department of Nutrition and Health Sciences, the University of Nebraska, Lincoln, Nebraska 68583
| | - Timothy Carr
- From the Department of Nutrition and Health Sciences, the University of Nebraska, Lincoln, Nebraska 68583
| | - Sathish Kumar Natarajan
- From the Department of Nutrition and Health Sciences, the University of Nebraska, Lincoln, Nebraska 68583
| | - Soonkyu Chung
- From the Department of Nutrition and Health Sciences, the University of Nebraska, Lincoln, Nebraska 68583
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18
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Jager J, Wang F, Fang B, Lim HW, Peed LC, Steger DJ, Won KJ, Kharitonenkov A, Adams AC, Lazar MA. The Nuclear Receptor Rev-erbα Regulates Adipose Tissue-specific FGF21 Signaling. J Biol Chem 2016; 291:10867-75. [PMID: 27002153 DOI: 10.1074/jbc.m116.719120] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [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: 02/01/2016] [Indexed: 01/14/2023] Open
Abstract
FGF21 is an atypical member of the FGF family that functions as a hormone to regulate carbohydrate and lipid metabolism. Here we demonstrate that the actions of FGF21 in mouse adipose tissue, but not in liver, are modulated by the nuclear receptor Rev-erbα, a potent transcriptional repressor. Interrogation of genes induced in the absence of Rev-erbα for Rev-erbα-binding sites identified βKlotho, an essential coreceptor for FGF21, as a direct target gene of Rev-erbα in white adipose tissue but not liver. Rev-erbα ablation led to the robust elevated expression of βKlotho. Consequently, the effects of FGF21 were markedly enhanced in the white adipose tissue of mice lacking Rev-erbα. A major Rev-erbα-controlled enhancer at the Klb locus was also bound by the adipocytic transcription factor peroxisome proliferator-activated receptor (PPAR) γ, which regulates its activity in the opposite direction. These findings establish Rev-erbα as a specific modulator of FGF21 signaling in adipose tissue.
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Affiliation(s)
- Jennifer Jager
- From the Division of Endocrinology, Diabetes, and Metabolism, Departments of Medicine and Genetics, and Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Fenfen Wang
- From the Division of Endocrinology, Diabetes, and Metabolism, Departments of Medicine and Genetics, and Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Bin Fang
- From the Division of Endocrinology, Diabetes, and Metabolism, Departments of Medicine and Genetics, and Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Hee-Woong Lim
- From the Division of Endocrinology, Diabetes, and Metabolism, Departments of Medicine and Genetics, and Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Lindsey C Peed
- From the Division of Endocrinology, Diabetes, and Metabolism, Departments of Medicine and Genetics, and Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - David J Steger
- From the Division of Endocrinology, Diabetes, and Metabolism, Departments of Medicine and Genetics, and Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Kyoung-Jae Won
- From the Division of Endocrinology, Diabetes, and Metabolism, Departments of Medicine and Genetics, and Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Alexei Kharitonenkov
- the Department of Chemistry, Indiana University Bloomington, Bloomington, Indiana 47405, and
| | - Andrew C Adams
- the Lilly Research Laboratories, Lilly Corporate Center, Indianapolis, Indiana 46285
| | - Mitchell A Lazar
- From the Division of Endocrinology, Diabetes, and Metabolism, Departments of Medicine and Genetics, and Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104,
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19
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Gosejacob D, Jäger PS, Vom Dorp K, Frejno M, Carstensen AC, Köhnke M, Degen J, Dörmann P, Hoch M. Ceramide Synthase 5 Is Essential to Maintain C16:0-Ceramide Pools and Contributes to the Development of Diet-induced Obesity. J Biol Chem 2016; 291:6989-7003. [PMID: 26853464 DOI: 10.1074/jbc.m115.691212] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [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: 09/22/2015] [Indexed: 01/22/2023] Open
Abstract
Ceramides are bioactive sphingolipids, which are composed of sphingoid bases carrying acyl chains of various lengths. Ceramides are synthesized by a family of six ceramide synthases (CerS) in mammals, which produce ceramides with differentN-linked acyl chains. Increased ceramide levels are known to contribute to the development of obesity and insulin resistance. Recently, it has been demonstrated that the ceramide acylation pattern is of particular importance for an organism to maintain energy homeostasis. However, which of theCerSfamily members are involved in this process is not yet completely known. Using newly developedCerS5knock-out mice, we show here thatCerS5is essential to maintain cellular C16:0sphingolipid pools in lung, spleen, muscle, liver, and white adipose tissue. Glycerophospholipid levels inCerS5-deficient mice were not altered. We found a strong impact of CerS5-dependent ceramide synthesis in white adipose tissue after high fat diet feeding. In skeletal muscle, liver, and spleen, C16:0-ceramide levels were altered independent of feeding conditions. The loss ofCerS5is associated with reduced weight gain and improved systemic health, including maintenance of glucose homeostasis and reduced white adipose tissue inflammation after high fat diet challenge. Our findings indicate that reduction of endogenous C16:0-ceramide by genetic inhibition ofCerS5is sufficient to ameliorate obesity and its comorbidities.
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Affiliation(s)
- Dominic Gosejacob
- From the LIMES-Institute, Program Unit Development, Genetics and Molecular Physiology, Molecular Developmental Biology, University of Bonn, Carl-Troll-Strasse 31 and
| | - Philipp S Jäger
- From the LIMES-Institute, Program Unit Development, Genetics and Molecular Physiology, Molecular Developmental Biology, University of Bonn, Carl-Troll-Strasse 31 and
| | - Katharina Vom Dorp
- IMBIO, Molecular Biotechnology, University of Bonn, Karlrobert-Kreiten-Str. 13, 53115 Bonn, Germany
| | - Martin Frejno
- From the LIMES-Institute, Program Unit Development, Genetics and Molecular Physiology, Molecular Developmental Biology, University of Bonn, Carl-Troll-Strasse 31 and
| | - Anne C Carstensen
- From the LIMES-Institute, Program Unit Development, Genetics and Molecular Physiology, Molecular Developmental Biology, University of Bonn, Carl-Troll-Strasse 31 and
| | - Monika Köhnke
- From the LIMES-Institute, Program Unit Development, Genetics and Molecular Physiology, Molecular Developmental Biology, University of Bonn, Carl-Troll-Strasse 31 and
| | - Joachim Degen
- From the LIMES-Institute, Program Unit Development, Genetics and Molecular Physiology, Molecular Developmental Biology, University of Bonn, Carl-Troll-Strasse 31 and
| | - Peter Dörmann
- IMBIO, Molecular Biotechnology, University of Bonn, Karlrobert-Kreiten-Str. 13, 53115 Bonn, Germany
| | - Michael Hoch
- From the LIMES-Institute, Program Unit Development, Genetics and Molecular Physiology, Molecular Developmental Biology, University of Bonn, Carl-Troll-Strasse 31 and
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20
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Oue K, Zhang J, Harada-Hada K, Asano S, Yamawaki Y, Hayashiuchi M, Furusho H, Takata T, Irifune M, Hirata M, Kanematsu T. Phospholipase C-related Catalytically Inactive Protein Is a New Modulator of Thermogenesis Promoted by β-Adrenergic Receptors in Brown Adipocytes. J Biol Chem 2015; 291:4185-96. [PMID: 26706316 DOI: 10.1074/jbc.m115.705723] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [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: 11/20/2015] [Indexed: 11/06/2022] Open
Abstract
Phospholipase C-related catalytically inactive protein (PRIP) was first identified as an inositol 1,4,5-trisphosphate-binding protein, and was later found to be involved in a variety of cellular events, particularly those related to protein phosphatases. We previously reported that Prip knock-out (KO) mice exhibit a lean phenotype with a small amount of white adipose tissue. In the present study, we examined whether PRIP is involved in energy metabolism, which could explain the lean phenotype, using high-fat diet (HFD)-fed mice. Prip-KO mice showed resistance to HFD-induced obesity, resulting in protection from glucose metabolism dysfunction and insulin resistance. Energy expenditure and body temperature at night were significantly higher in Prip-KO mice than in wild-type mice. Gene and protein expression of uncoupling protein 1 (UCP1), a thermogenic protein, was up-regulated in Prip-KO brown adipocytes in thermoneutral or cold environments. These phenotypes were caused by the promotion of lipolysis in Prip-KO brown adipocytes, which is triggered by up-regulation of phosphorylation of the lipolysis-related proteins hormone-sensitive lipase and perilipin, followed by activation of UCP1 and/or up-regulation of thermogenesis-related genes (e.g. peroxisome proliferator-activated receptor-γ coactivator-1α). The results indicate that PRIP negatively regulates UCP1-mediated thermogenesis in brown adipocytes.
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Affiliation(s)
- Kana Oue
- From the Departments of Cellular and Molecular Pharmacology, Dental Anesthesiology, and
| | - Jun Zhang
- From the Departments of Cellular and Molecular Pharmacology
| | | | - Satoshi Asano
- From the Departments of Cellular and Molecular Pharmacology
| | | | | | - Hisako Furusho
- Oral and Maxillofacial Pathobiology, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8553 and
| | - Takashi Takata
- Oral and Maxillofacial Pathobiology, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8553 and
| | | | - Masato Hirata
- the Laboratory of Molecular and Cellular Biochemistry, Faculty of Dental Science, Kyushu University, Fukuoka 812-8582, Japan
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21
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Okla M, Wang W, Kang I, Pashaj A, Carr T, Chung S. Activation of Toll-like receptor 4 (TLR4) attenuates adaptive thermogenesis via endoplasmic reticulum stress. J Biol Chem 2015; 290:26476-90. [PMID: 26370079 DOI: 10.1074/jbc.m115.677724] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Indexed: 12/26/2022] Open
Abstract
Adaptive thermogenesis is the cellular process transforming chemical energy into heat in response to cold. A decrease in adaptive thermogenesis is a contributing factor to obesity. However, the molecular mechanisms responsible for the compromised adaptive thermogenesis in obese subjects have not yet been elucidated. In this study we hypothesized that Toll-like receptor 4 (TLR4) activation and subsequent inflammatory responses are key regulators to suppress adaptive thermogenesis. To test this hypothesis, C57BL/6 mice were either fed a palmitate-enriched high fat diet or administered with chronic low-dose LPS before cold acclimation. TLR4 stimulation by a high fat diet or LPS were both associated with reduced core body temperature and heat release. Impairment of thermogenic activation was correlated with diminished expression of brown-specific markers and mitochondrial dysfunction in subcutaneous white adipose tissue (sWAT). Defective sWAT browning was concomitant with elevated levels of endoplasmic reticulum (ER) stress and autophagy. Consistently, TLR4 activation by LPS abolished cAMP-induced up-regulation of uncoupling protein 1 (UCP1) in primary human adipocytes, which was reversed by silencing of C/EBP homologous protein (CHOP). Moreover, the inactivation of ER stress by genetic deletion of CHOP or chemical chaperone conferred a resistance to the LPS-induced suppression of adaptive thermogenesis. Collectively, our data indicate the existence of a novel signaling network that links TLR4 activation, ER stress, and mitochondrial dysfunction, thereby antagonizing thermogenic activation of sWAT. Our results also suggest that TLR4/ER stress axis activation may be a responsible mechanism for obesity-mediated defective brown adipose tissue activation.
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Affiliation(s)
- Meshail Okla
- From the Department of Nutrition and Health Sciences, the University of Nebraska-Lincoln, Lincoln, Nebraska 68583
| | - Wei Wang
- From the Department of Nutrition and Health Sciences, the University of Nebraska-Lincoln, Lincoln, Nebraska 68583
| | - Inhae Kang
- From the Department of Nutrition and Health Sciences, the University of Nebraska-Lincoln, Lincoln, Nebraska 68583
| | - Anjeza Pashaj
- From the Department of Nutrition and Health Sciences, the University of Nebraska-Lincoln, Lincoln, Nebraska 68583
| | - Timothy Carr
- From the Department of Nutrition and Health Sciences, the University of Nebraska-Lincoln, Lincoln, Nebraska 68583
| | - Soonkyu Chung
- From the Department of Nutrition and Health Sciences, the University of Nebraska-Lincoln, Lincoln, Nebraska 68583
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22
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Abstract
Obesity is a phenotype resulting from a series of causative factors with a variable risk of complications. Etiologic diversity requires personalized prevention and treatment. Imaging procedures offer the potential to investigate the interplay between organs and pathways underlying energy intake and consumption in an integrated manner, and may open the perspective to classify and treat obesity according to causative mechanisms. This review illustrates the contribution provided by imaging studies to the understanding of human obesity, starting with the regulation of food intake and intestinal metabolism, followed by the role of adipose tissue in storing, releasing, and utilizing substrates, including the interconversion of white and brown fat, and concluding with the examination of imaging risk indicators related to complications, including type 2 diabetes, liver pathologies, cardiac and kidney diseases, and sleep disorders. The imaging modalities include (1) positron emission tomography to quantify organ-specific perfusion and substrate metabolism; (2) computed tomography to assess tissue density as an indicator of fat content and browning/ whitening; (3) ultrasounds to examine liver steatosis, stiffness, and inflammation; and (4) magnetic resonance techniques to assess blood oxygenation levels in the brain, liver stiffness, and metabolite contents (triglycerides, fatty acids, glucose, phosphocreatine, ATP, and acetylcarnitine) in a variety of organs.
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Affiliation(s)
- Patricia Iozzo
- Institute of Clinical Physiology, National Research Council (CNR), Pisa, Italy.,The Turku PET Centre, University of Turku, Turku, Finland
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23
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Foryst-Ludwig A, Kreissl MC, Benz V, Brix S, Smeir E, Ban Z, Januszewicz E, Salatzki J, Grune J, Schwanstecher AK, Blumrich A, Schirbel A, Klopfleisch R, Rothe M, Blume K, Halle M, Wolfarth B, Kershaw EE, Kintscher U. Adipose Tissue Lipolysis Promotes Exercise-induced Cardiac Hypertrophy Involving the Lipokine C16:1n7-Palmitoleate. J Biol Chem 2015; 290:23603-15. [PMID: 26260790 DOI: 10.1074/jbc.m115.645341] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [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: 02/13/2015] [Indexed: 12/28/2022] Open
Abstract
Endurance exercise training induces substantial adaptive cardiac modifications such as left ventricular hypertrophy (LVH). Simultaneously to the development of LVH, adipose tissue (AT) lipolysis becomes elevated upon endurance training to cope with enhanced energy demands. In this study, we investigated the impact of adipose tissue lipolysis on the development of exercise-induced cardiac hypertrophy. Mice deficient for adipose triglyceride lipase (Atgl) in AT (atATGL-KO) were challenged with chronic treadmill running. Exercise-induced AT lipolytic activity was significantly reduced in atATGL-KO mice accompanied by the absence of a plasma fatty acid (FA) increase. These processes were directly associated with a prominent attenuation of myocardial FA uptake in atATGL-KO and a significant reduction of the cardiac hypertrophic response to exercise. FA serum profiling revealed palmitoleic acid (C16:1n7) as a new molecular co-mediator of exercise-induced cardiac hypertrophy by inducing nonproliferative cardiomyocyte growth. In parallel, serum FA analysis and echocardiography were performed in 25 endurance athletes. In consonance, the serum C16:1n7 palmitoleate level exhibited a significantly positive correlation with diastolic interventricular septum thickness in those athletes. No correlation existed between linoleic acid (18:2n6) and diastolic interventricular septum thickness. Collectively, our data provide the first evidence that adipose tissue lipolysis directly promotes the development of exercise-induced cardiac hypertrophy involving the lipokine C16:1n7 palmitoleate as a molecular co-mediator. The identification of a lipokine involved in physiological cardiac growth may help to develop future lipid-based therapies for pathological LVH or heart failure.
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Affiliation(s)
- Anna Foryst-Ludwig
- From the Institute of Pharmacology, Center for Cardiovascular Research, Charité-Universitaetsmedizin Berlin, 10115 Berlin, Germany, the DZHK (German Center for Cardiovascular Research), 10115 Berlin, Germany
| | - Michael C Kreissl
- the Department of Nuclear Medicine, University Hospital Wuerzburg, 97080 Wuerzburg, Germany
| | - Verena Benz
- From the Institute of Pharmacology, Center for Cardiovascular Research, Charité-Universitaetsmedizin Berlin, 10115 Berlin, Germany
| | - Sarah Brix
- From the Institute of Pharmacology, Center for Cardiovascular Research, Charité-Universitaetsmedizin Berlin, 10115 Berlin, Germany
| | - Elia Smeir
- From the Institute of Pharmacology, Center for Cardiovascular Research, Charité-Universitaetsmedizin Berlin, 10115 Berlin, Germany
| | - Zsofia Ban
- From the Institute of Pharmacology, Center for Cardiovascular Research, Charité-Universitaetsmedizin Berlin, 10115 Berlin, Germany
| | - Elżbieta Januszewicz
- From the Institute of Pharmacology, Center for Cardiovascular Research, Charité-Universitaetsmedizin Berlin, 10115 Berlin, Germany
| | - Janek Salatzki
- From the Institute of Pharmacology, Center for Cardiovascular Research, Charité-Universitaetsmedizin Berlin, 10115 Berlin, Germany
| | - Jana Grune
- From the Institute of Pharmacology, Center for Cardiovascular Research, Charité-Universitaetsmedizin Berlin, 10115 Berlin, Germany
| | - Anne-Kathrin Schwanstecher
- From the Institute of Pharmacology, Center for Cardiovascular Research, Charité-Universitaetsmedizin Berlin, 10115 Berlin, Germany
| | - Annelie Blumrich
- From the Institute of Pharmacology, Center for Cardiovascular Research, Charité-Universitaetsmedizin Berlin, 10115 Berlin, Germany
| | - Andreas Schirbel
- the Department of Nuclear Medicine, University Hospital Wuerzburg, 97080 Wuerzburg, Germany
| | - Robert Klopfleisch
- the Department of Veterinary Pathology, College of Veterinary Medicine, Freie Universität Berlin, 14163 Berlin, Germany
| | | | - Katharina Blume
- the Department of Prevention, Rehabilitation, and Sports Medicine, Technische Universitaet Muenchen, 80809 Muenchen, Germany
| | - Martin Halle
- the Department of Prevention, Rehabilitation, and Sports Medicine, Technische Universitaet Muenchen, 80809 Muenchen, Germany, the DZHK (German Center for Cardiovascular Research), Munich Heart Alliance, 80809 Munich, Germany
| | - Bernd Wolfarth
- the Department of Sports Medicine, Humboldt University/Charité-Universitaetsmedizin Berlin, 10115 Berlin, Germany
| | - Erin E Kershaw
- the Division of Endocrinology and Metabolism, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, and
| | - Ulrich Kintscher
- From the Institute of Pharmacology, Center for Cardiovascular Research, Charité-Universitaetsmedizin Berlin, 10115 Berlin, Germany, the DZHK (German Center for Cardiovascular Research), 10115 Berlin, Germany
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24
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Pierce JR, Maples JM, Hickner RC. IL-15 concentrations in skeletal muscle and subcutaneous adipose tissue in lean and obese humans: local effects of IL-15 on adipose tissue lipolysis. Am J Physiol Endocrinol Metab 2015; 308:E1131-9. [PMID: 25921578 PMCID: PMC4469810 DOI: 10.1152/ajpendo.00575.2014] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [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] [Received: 12/08/2014] [Accepted: 04/27/2015] [Indexed: 01/05/2023]
Abstract
Animal/cell investigations indicate that there is a decreased adipose tissue mass resulting from skeletal muscle (SkM) IL-15 secretion (e.g., SkM-blood-adipose tissue axis). IL-15 could regulate fat mass accumulation in obesity via lipolysis, although this has not been investigated in humans. Therefore, the purpose was to examine whether SkM and/or subcutaneous adipose tissue (SCAT) IL-15 concentrations were correlated with SCAT lipolysis in lean and obese humans and determine whether IL-15 perfusion could induce lipolysis in human SCAT. Local SkM and abdominal SCAT IL-15 (microdialysis) and circulating IL-15 (blood) were sampled in lean (BMI: 23.1 ± 1.9 kg/m(2); n = 10) and obese (BMI: 34.7 ± 3.5 kg/m(2); n = 10) subjects at rest/during 1-h cycling exercise. Lipolysis (SCAT interstitial glycerol concentration) was compared against local/systemic IL-15. An additional probe in SCAT was perfused with IL-15 to assess direct lipolytic responses. SkM IL-15 was not different between lean and obese subjects (P = 0.45), whereas SCAT IL-15 was higher in obese vs. lean subjects (P = 0.02) and was correlated with SCAT lipolysis (r = 0.45, P = 0.05). Exercise increased SCAT lipolysis in lean and obese (P < 0.01), but exercise-induced SCAT lipolysis changes were not correlated with exercise-induced SCAT IL-15 changes. Microdialysis perfusion resulting in physiological IL-15 concentrations in the adipose tissue interstitium increased lipolysis in lean (P = 0.04) but suppressed lipolysis in obese (P < 0.01). Although we found no support for a human IL-15 SkM-blood-adipose tissue axis, IL-15 may be produced in/act on the abdominal SCAT depot. The extent to which this autocrine/paracrine IL-15 action regulates human body composition remains unknown.
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Affiliation(s)
- Joseph R Pierce
- Human Performance Laboratory, East Carolina University, Greenville, North Carolina; Departments of Kinesiology and
| | - Jill M Maples
- Human Performance Laboratory, East Carolina University, Greenville, North Carolina; Departments of Kinesiology and
| | - Robert C Hickner
- Human Performance Laboratory, East Carolina University, Greenville, North Carolina; Departments of Kinesiology and Physiology and Center for Health Disparities, East Carolina University, Greenville, North Carolina; and Discipline of Biokinetics, Exercise, and Leisure Sciences, School of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
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25
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Liaset B, Hao Q, Jørgensen H, Hallenborg P, Du ZY, Ma T, Marschall HU, Kruhøffer M, Li R, Li Q, Yde CC, Criales G, Bertram HC, Mellgren G, Øfjord ES, Lock EJ, Espe M, Frøyland L, Madsen L, Kristiansen K. Nutritional regulation of bile acid metabolism is associated with improved pathological characteristics of the metabolic syndrome. J Biol Chem 2011; 286:28382-95. [PMID: 21680746 PMCID: PMC3151081 DOI: 10.1074/jbc.m111.234732] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2011] [Revised: 06/01/2011] [Indexed: 12/31/2022] Open
Abstract
Bile acids (BAs) are powerful regulators of metabolism, and mice treated orally with cholic acid are protected from diet-induced obesity, hepatic lipid accumulation, and increased plasma triacylglycerol (TAG) and glucose levels. Here, we show that plasma BA concentration in rats was elevated by exchanging the dietary protein source from casein to salmon protein hydrolysate (SPH). Importantly, the SPH-treated rats were resistant to diet-induced obesity. SPH-treated rats had reduced fed state plasma glucose and TAG levels and lower TAG in liver. The elevated plasma BA concentration was associated with induction of genes involved in energy metabolism and uncoupling, Dio2, Pgc-1α, and Ucp1, in interscapular brown adipose tissue. Interestingly, the same transcriptional pattern was found in white adipose tissue depots of both abdominal and subcutaneous origin. Accordingly, rats fed SPH-based diet exhibited increased whole body energy expenditure and heat dissipation. In skeletal muscle, expressions of the peroxisome proliferator-activated receptor β/δ target genes (Cpt-1b, Angptl4, Adrp, and Ucp3) were induced. Pharmacological removal of BAs by inclusion of 0.5 weight % cholestyramine to the high fat SPH diet attenuated the reduction in abdominal obesity, the reduction in liver TAG, and the decrease in nonfasted plasma TAG and glucose levels. Induction of Ucp3 gene expression in muscle by SPH treatment was completely abolished by cholestyramine inclusion. Taken together, our data provide evidence that bile acid metabolism can be modulated by diet and that such modulation may prevent/ameliorate the characteristic features of the metabolic syndrome.
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Affiliation(s)
- Bjørn Liaset
- From the National Institute of Nutrition and Seafood Research, 5817 Bergen, Norway
| | - Qin Hao
- the Department of Biology, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Henry Jørgensen
- the Department of Animal Health, Welfare, and Nutrition, Aarhus University, 8830 Tjele, Denmark
| | - Philip Hallenborg
- the Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense Denmark
| | - Zhen-Yu Du
- From the National Institute of Nutrition and Seafood Research, 5817 Bergen, Norway
| | - Tao Ma
- the Department of Biology, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Hanns-Ulrich Marschall
- the Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, 40530 Gothenburg, Sweden
| | | | - Ruiqiang Li
- the Beijing Genomic Institute, Shenzhen 518083, China
| | - Qibin Li
- the Beijing Genomic Institute, Shenzhen 518083, China
| | - Christian Clement Yde
- the Department of Animal Health, Welfare, and Nutrition, Aarhus University, 8830 Tjele, Denmark
| | - Gabriel Criales
- From the National Institute of Nutrition and Seafood Research, 5817 Bergen, Norway
| | - Hanne C. Bertram
- the Department of Food Science, Aarhus University, 5792 Aarslev, Denmark
| | - Gunnar Mellgren
- the Institute of Medicine, University of Bergen, 5021 Bergen, Norway
- the Hormone Laboratory, Haukeland University Hospital, 5021 Bergen, Norway, and
| | | | - Erik-Jan Lock
- From the National Institute of Nutrition and Seafood Research, 5817 Bergen, Norway
| | - Marit Espe
- From the National Institute of Nutrition and Seafood Research, 5817 Bergen, Norway
| | - Livar Frøyland
- From the National Institute of Nutrition and Seafood Research, 5817 Bergen, Norway
| | - Lise Madsen
- From the National Institute of Nutrition and Seafood Research, 5817 Bergen, Norway
- the Department of Biology, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Karsten Kristiansen
- the Department of Biology, University of Copenhagen, 2200 Copenhagen, Denmark
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26
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Nyman E, Brännmark C, Palmér R, Brugård J, Nyström FH, Strålfors P, Cedersund G. A hierarchical whole-body modeling approach elucidates the link between in Vitro insulin signaling and in Vivo glucose homeostasis. J Biol Chem 2011; 286:26028-41. [PMID: 21572040 PMCID: PMC3138269 DOI: 10.1074/jbc.m110.188987] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2010] [Revised: 03/08/2011] [Indexed: 01/15/2023] Open
Abstract
Type 2 diabetes is a metabolic disease that profoundly affects energy homeostasis. The disease involves failure at several levels and subsystems and is characterized by insulin resistance in target cells and tissues (i.e. by impaired intracellular insulin signaling). We have previously used an iterative experimental-theoretical approach to unravel the early insulin signaling events in primary human adipocytes. That study, like most insulin signaling studies, is based on in vitro experimental examination of cells, and the in vivo relevance of such studies for human beings has not been systematically examined. Herein, we develop a hierarchical model of the adipose tissue, which links intracellular insulin control of glucose transport in human primary adipocytes with whole-body glucose homeostasis. An iterative approach between experiments and minimal modeling allowed us to conclude that it is not possible to scale up the experimentally determined glucose uptake by the isolated adipocytes to match the glucose uptake profile of the adipose tissue in vivo. However, a model that additionally includes insulin effects on blood flow in the adipose tissue and GLUT4 translocation due to cell handling can explain all data, but neither of these additions is sufficient independently. We also extend the minimal model to include hierarchical dynamic links to more detailed models (both to our own models and to those by others), which act as submodules that can be turned on or off. The resulting multilevel hierarchical model can merge detailed results on different subsystems into a coherent understanding of whole-body glucose homeostasis. This hierarchical modeling can potentially create bridges between other experimental model systems and the in vivo human situation and offers a framework for systematic evaluation of the physiological relevance of in vitro obtained molecular/cellular experimental data.
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Affiliation(s)
- Elin Nyman
- From the Department of Clinical and Experimental Medicine, Diabetes and Integrative Systems Biology and
| | - Cecilia Brännmark
- From the Department of Clinical and Experimental Medicine, Diabetes and Integrative Systems Biology and
| | - Robert Palmér
- From the Department of Clinical and Experimental Medicine, Diabetes and Integrative Systems Biology and
| | - Jan Brugård
- MathCore Engineering AB, SE58330 Linköping, Sweden, and
| | - Fredrik H. Nyström
- the Department of Medical and Health Sciences, Linköping University, SE58185 Linköping, Sweden
| | - Peter Strålfors
- From the Department of Clinical and Experimental Medicine, Diabetes and Integrative Systems Biology and
| | - Gunnar Cedersund
- From the Department of Clinical and Experimental Medicine, Diabetes and Integrative Systems Biology and
- the School of Life Sciences, Freiburg Institute of Advanced Sciences, 79104 Freiburg, Germany
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27
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Giralt A, Hondares E, Villena JA, Ribas F, Díaz-Delfín J, Giralt M, Iglesias R, Villarroya F. Peroxisome proliferator-activated receptor-gamma coactivator-1alpha controls transcription of the Sirt3 gene, an essential component of the thermogenic brown adipocyte phenotype. J Biol Chem 2011; 286:16958-66. [PMID: 21454513 PMCID: PMC3089539 DOI: 10.1074/jbc.m110.202390] [Citation(s) in RCA: 165] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2010] [Revised: 03/04/2011] [Indexed: 01/14/2023] Open
Abstract
Sirt3 (silent mating type information regulation 2, homolog 3), a member of the sirtuin family of protein deacetylases with multiple actions on metabolism and gene expression is expressed in association with brown adipocyte differentiation. Using Sirt3-null brown adipocytes, we determined that Sirt3 is required for an appropriate responsiveness of cells to noradrenergic, cAMP-mediated activation of the expression of brown adipose tissue thermogenic genes. The transcriptional coactivator Pgc-1α (peroxisome proliferator-activated receptor-γ coactivator-1α) induced Sirt3 gene expression in white adipocytes and embryonic fibroblasts as part of its overall induction of a brown adipose tissue-specific pattern of gene expression. In cells lacking Sirt3, Pgc-1α failed to fully induce the expression of brown fat-specific thermogenic genes. Pgc-1α activates Sirt3 gene transcription through coactivation of the orphan nuclear receptor Err (estrogen-related receptor)-α, which bound the proximal Sirt3 gene promoter region. Errα knockdown assays indicated that Errα is required for full induction of Sirt3 gene expression in response to Pgc-1α. The present results indicate that Pgc-1α controls Sirt3 gene expression and this action is an essential component of the overall mechanisms by which Pgc-1α induces the full acquisition of a brown adipocyte differentiated phenotype.
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Affiliation(s)
- Albert Giralt
- From the Departament de Bioquímica i Biologia Molecular, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, and CIBER Fisiopatologia de la Obesidad y Nutrición, 08028 Barcelona, Spain and
| | - Elayne Hondares
- From the Departament de Bioquímica i Biologia Molecular, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, and CIBER Fisiopatologia de la Obesidad y Nutrición, 08028 Barcelona, Spain and
| | | | - Francesc Ribas
- From the Departament de Bioquímica i Biologia Molecular, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, and CIBER Fisiopatologia de la Obesidad y Nutrición, 08028 Barcelona, Spain and
| | - Julieta Díaz-Delfín
- From the Departament de Bioquímica i Biologia Molecular, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, and CIBER Fisiopatologia de la Obesidad y Nutrición, 08028 Barcelona, Spain and
| | - Marta Giralt
- From the Departament de Bioquímica i Biologia Molecular, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, and CIBER Fisiopatologia de la Obesidad y Nutrición, 08028 Barcelona, Spain and
| | - Roser Iglesias
- From the Departament de Bioquímica i Biologia Molecular, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, and CIBER Fisiopatologia de la Obesidad y Nutrición, 08028 Barcelona, Spain and
| | - Francesc Villarroya
- From the Departament de Bioquímica i Biologia Molecular, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, and CIBER Fisiopatologia de la Obesidad y Nutrición, 08028 Barcelona, Spain and
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