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Ji L, Zhao Y, He L, Zhao J, Gao T, Liu F, Qi B, Kang F, Wang G, Zhao Y, Guo H, He Y, Li F, Huang Q, Xing J. AKAP1 Deficiency Attenuates Diet-Induced Obesity and Insulin Resistance by Promoting Fatty Acid Oxidation and Thermogenesis in Brown Adipocytes. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:2002794. [PMID: 33747723 PMCID: PMC7967052 DOI: 10.1002/advs.202002794] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 11/20/2020] [Indexed: 05/06/2023]
Abstract
Altering the balance between energy intake and expenditure is a major strategy for treating obesity. Nonetheless, despite the progression in antiobesity drugs on appetite suppression, therapies aimed at increasing energy expenditure are limited. Here, knockout ofAKAP1, a signaling hub on outer mitochondrial membrane, renders mice resistant to diet-induced obesity.AKAP1 knockout significantly enhances energy expenditure and thermogenesis in brown adipose tissues (BATs) of obese mice. Restoring AKAP1 expression in BAT clearly reverses the beneficial antiobesity effect in AKAP1-/- mice. Mechanistically, AKAP1 remarkably decreases fatty acid β-oxidation (FAO) by phosphorylating ACSL1 to inhibit its activity in a protein-kinase-A-dependent manner and thus inhibits thermogenesis in brown adipocytes. Importantly, AKAP1 peptide inhibitor effectively alleviates diet-induced obesity and insulin resistance. Altogether, the findings demonstrate that AKAP1 functions as a brake of FAO to promote diet-induced obesity, which may be used as a potential therapeutic target for obesity.
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Affiliation(s)
- Lele Ji
- State Key Laboratory of Cancer Biology and Department of Physiology and PathophysiologyFourth Military Medical UniversityXi'anShaanxi710032China
- National Demonstration Center for Experimental Preclinical Medicine EducationFourth Military Medical UniversityXi'anShaanxi710032China
| | - Ya Zhao
- State Key Laboratory of Cancer Biology and Department of Physiology and PathophysiologyFourth Military Medical UniversityXi'anShaanxi710032China
- Laboratory Animal CenterFourth Military Medical UniversityXi'anShaanxi710032China
| | - Linjie He
- State Key Laboratory of Cancer Biology and Department of Physiology and PathophysiologyFourth Military Medical UniversityXi'anShaanxi710032China
| | - Jing Zhao
- State Key Laboratory of Cancer Biology and Department of Physiology and PathophysiologyFourth Military Medical UniversityXi'anShaanxi710032China
| | - Tian Gao
- State Key Laboratory of Cancer Biology and Department of Physiology and PathophysiologyFourth Military Medical UniversityXi'anShaanxi710032China
| | - Fengzhou Liu
- Department of CardiologyXijing HospitalFourth Military Medical UniversityXi'anShaanxi710032China
| | - Bingchao Qi
- Department of CardiologyXijing HospitalFourth Military Medical UniversityXi'anShaanxi710032China
| | - Fei Kang
- Department of Nuclear MedicineXijing HospitalFourth Military Medical UniversityXi'anShaanxi710032China
| | - Gang Wang
- State Key Laboratory of Cancer Biology and Department of Physiology and PathophysiologyFourth Military Medical UniversityXi'anShaanxi710032China
| | - Yilin Zhao
- State Key Laboratory of Cancer Biology and Department of Physiology and PathophysiologyFourth Military Medical UniversityXi'anShaanxi710032China
| | - Haitao Guo
- State Key Laboratory of Cancer Biology and Department of Physiology and PathophysiologyFourth Military Medical UniversityXi'anShaanxi710032China
| | - Yuanfang He
- State Key Laboratory of Cancer Biology and Department of Physiology and PathophysiologyFourth Military Medical UniversityXi'anShaanxi710032China
| | - Fei Li
- Department of CardiologyXijing HospitalFourth Military Medical UniversityXi'anShaanxi710032China
| | - Qichao Huang
- State Key Laboratory of Cancer Biology and Department of Physiology and PathophysiologyFourth Military Medical UniversityXi'anShaanxi710032China
| | - Jinliang Xing
- State Key Laboratory of Cancer Biology and Department of Physiology and PathophysiologyFourth Military Medical UniversityXi'anShaanxi710032China
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Li W, Ma J, Jiang Q, Zhang T, Qi Q, Cheng Y. Fast Noninvasive Measurement of Brown Adipose Tissue in Living Mice by Near-Infrared Fluorescence and Photoacoustic Imaging. Anal Chem 2020; 92:3787-3794. [PMID: 32066237 DOI: 10.1021/acs.analchem.9b05162] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Aberrant brown adipose tissue (BAT) metabolism is linked to obesity as well as other metabolic disorders. However, the paucity of imaging tools limits the study of in vivo BAT metabolism in animal models. The current work evaluated a heptamethine dye (CyHF-8) in living mice as a dual-modality BAT-avid molecular probe for two imaging approaches, including near-infrared fluorescence imaging (NIRF) and photoacoustic imaging (PAI). CyHF-8 exhibited favorable spectral properties in the near-infrared window (786/787/805 nm) and accumulated in the subcellular mitochondria of brown adipocytes. After intravenous injection of CyHF-8, NIRF and PAI were both capable of noninvasively detecting interscapular BAT at early time points in living mice. Quantitative analysis of NIRF and PAI images showed that CyHF-8 signals respond to dynamic BAT changes in mice stimulated by norepinephrine (NE) and in diabetic mice induced by streptozotocin (STZ). In summary, dual-modality NIRF/PAI probe CyHF-8 can be used for both NIRF and PAI to noninvasively assess BAT metabolism in living animals.
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Affiliation(s)
- Wanyun Li
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Jing Ma
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Qian Jiang
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Ting Zhang
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Qingrong Qi
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Yan Cheng
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
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Baranwal A, Mirbolooki MR, Mukherjee J. Initial Assessment of β3-Adrenoceptor-Activated Brown Adipose Tissue in Streptozotocin-Induced Type 1 Diabetes Rodent Model Using [18F]Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography. Mol Imaging 2016; 14:22-33. [PMID: 26637263 DOI: 10.2310/7290.2015.00028] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Metabolic activity of brown adipose tissue (BAT) is activated by β3-adrenoceptor agonists and norepinephrine transporter (NET) blockers and is measurable using [(18)F]fluorodeoxyglucose ([(18)F]FDG) positron emission tomography/computed tomography (PET/CT) in rats. Using the streptozotocin (STZ)-treated rat model of type 1 diabetes mellitus (T1DM), we investigated BAT activity in this rat model under fasting and nonfasting conditions using [(18)F]FDG PET/CT. Drugs that enhance BAT activity may have a potential for therapeutic development in lowering blood sugar in insulin-resistant diabetes. Rats were rendered diabetic by administration of STZ and confirmed by glucose measures. [(18)F]FDG was injected in the rats (fasted or nonfasted) pretreated with either saline or β3-adrenoceptor agonist CL316,243 or the NET blocker atomoxetine for PET/CT scans. [(18)F]FDG metabolic activity was computed as standard uptake values (SUVs) in interscapular brown adipose tissue (IBAT) and compared across the different drug treatment conditions. Blood glucose levels > 500 mg/dL were established for the STZ-treated diabetic rats. Under fasting conditions, average uptake of [(18)F]FDG in the IBAT of STZ-treated diabetic rats was approximately 70% lower compared to that of normal rats. Both CL316,243 and atomoxetine activated IBAT in normal rats had an SUV > 5, whereas activation in STZ-treated rats was significantly lower. The agonist CL316,243 activated IBAT up to threefold compared to saline in the fasted STZ-treated rat. In the nonfasted rat, the IBAT activation was up by twofold by CL316243. Atomoxetine had a greater effect on lowering blood sugar levels compared to CL316,243 in the nonfasted rats. A significant reduction in metabolic activity was observed in the STZ-treated diabetic rodent model. Increased IBAT activity in the STZ-treated diabetic rat under nonfasted conditions using the β3-adrenoceptor agonist CL316,243 suggests a potential role of BAT in modulating blood sugar levels. Further studies are needed to evaluate the therapeutic role of β3-adrenoceptor agonists in insulin-resistant T1DM.
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Calderon-Dominguez M, Sebastián D, Fucho R, Weber M, Mir JF, García-Casarrubios E, Obregón MJ, Zorzano A, Valverde ÁM, Serra D, Herrero L. Carnitine Palmitoyltransferase 1 Increases Lipolysis, UCP1 Protein Expression and Mitochondrial Activity in Brown Adipocytes. PLoS One 2016; 11:e0159399. [PMID: 27438137 PMCID: PMC4954705 DOI: 10.1371/journal.pone.0159399] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 07/03/2016] [Indexed: 02/07/2023] Open
Abstract
The discovery of active brown adipose tissue (BAT) in adult humans and the fact that it is reduced in obese and diabetic patients have put a spotlight on this tissue as a key player in obesity-induced metabolic disorders. BAT regulates energy expenditure through thermogenesis; therefore, harnessing its thermogenic fat-burning power is an attractive therapeutic approach. We aimed to enhance BAT thermogenesis by increasing its fatty acid oxidation (FAO) rate. Thus, we expressed carnitine palmitoyltransferase 1AM (CPT1AM), a permanently active mutant form of CPT1A (the rate-limiting enzyme in FAO), in a rat brown adipocyte (rBA) cell line through adenoviral infection. We found that CPT1AM-expressing rBA have increased FAO, lipolysis, UCP1 protein levels and mitochondrial activity. Additionally, enhanced FAO reduced the palmitate-induced increase in triglyceride content and the expression of obese and inflammatory markers. Thus, CPT1AM-expressing rBA had enhanced fat-burning capacity and improved lipid-induced derangements. This indicates that CPT1AM-mediated increase in brown adipocytes FAO may be a new approach to the treatment of obesity-induced disorders.
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Affiliation(s)
- María Calderon-Dominguez
- Department of Biochemistry and Physiology, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, E-08028, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, E-28029, Madrid, Spain
| | - David Sebastián
- Institute for Research in Biomedicine (IRB Barcelona) and Departament de Bioquímica i Biologia Molecular, Facultat de Biologia, Universitat de Barcelona, E-08028, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, E-28029, Madrid, Spain
| | - Raquel Fucho
- Department of Biochemistry and Physiology, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, E-08028, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, E-28029, Madrid, Spain
| | - Minéia Weber
- Department of Biochemistry and Physiology, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, E-08028, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, E-28029, Madrid, Spain
| | - Joan F. Mir
- Department of Biochemistry and Physiology, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, E-08028, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, E-28029, Madrid, Spain
| | - Ester García-Casarrubios
- Instituto de Investigaciones Biomédicas Alberto Sols (CSIC-UAM) and Instituto de Investigación Sanitaria La Paz, 28029, Madrid, Spain
| | - María Jesús Obregón
- Instituto de Investigaciones Biomédicas Alberto Sols (CSIC-UAM) and Instituto de Investigación Sanitaria La Paz, 28029, Madrid, Spain
| | - Antonio Zorzano
- Institute for Research in Biomedicine (IRB Barcelona) and Departament de Bioquímica i Biologia Molecular, Facultat de Biologia, Universitat de Barcelona, E-08028, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, E-28029, Madrid, Spain
| | - Ángela M. Valverde
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, E-28029, Madrid, Spain
- Instituto de Investigaciones Biomédicas Alberto Sols (CSIC-UAM) and Instituto de Investigación Sanitaria La Paz, 28029, Madrid, Spain
| | - Dolors Serra
- Department of Biochemistry and Physiology, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, E-08028, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, E-28029, Madrid, Spain
| | - Laura Herrero
- Department of Biochemistry and Physiology, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, E-08028, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, E-28029, Madrid, Spain
- * E-mail:
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Calderon-Dominguez M, Mir JF, Fucho R, Weber M, Serra D, Herrero L. Fatty acid metabolism and the basis of brown adipose tissue function. Adipocyte 2016; 5:98-118. [PMID: 27386151 PMCID: PMC4916887 DOI: 10.1080/21623945.2015.1122857] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 10/13/2015] [Accepted: 11/12/2015] [Indexed: 12/21/2022] Open
Abstract
Obesity has reached epidemic proportions, leading to severe associated pathologies such as insulin resistance, cardiovascular disease, cancer and type 2 diabetes. Adipose tissue has become crucial due to its involvement in the pathogenesis of obesity-induced insulin resistance, and traditionally white adipose tissue has captured the most attention. However in the last decade the presence and activity of heat-generating brown adipose tissue (BAT) in adult humans has been rediscovered. BAT decreases with age and in obese and diabetic patients. It has thus attracted strong scientific interest, and any strategy to increase its mass or activity might lead to new therapeutic approaches to obesity and associated metabolic diseases. In this review we highlight the mechanisms of fatty acid uptake, trafficking and oxidation in brown fat thermogenesis. We focus on BAT's morphological and functional characteristics and fatty acid synthesis, storage, oxidation and use as a source of energy.
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Affiliation(s)
- María Calderon-Dominguez
- Department of Biochemistry and Molecular Biology, School of Pharmacy, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, Barcelona, Spain
- CIBER Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, Spain
| | - Joan F. Mir
- Department of Biochemistry and Molecular Biology, School of Pharmacy, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, Barcelona, Spain
- CIBER Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, Spain
| | - Raquel Fucho
- Department of Biochemistry and Molecular Biology, School of Pharmacy, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, Barcelona, Spain
- CIBER Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, Spain
| | - Minéia Weber
- Department of Biochemistry and Molecular Biology, School of Pharmacy, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, Barcelona, Spain
- CIBER Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, Spain
| | - Dolors Serra
- Department of Biochemistry and Molecular Biology, School of Pharmacy, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, Barcelona, Spain
- CIBER Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, Spain
| | - Laura Herrero
- Department of Biochemistry and Molecular Biology, School of Pharmacy, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, Barcelona, Spain
- CIBER Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, Spain
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Zhang X, Tian Y, Zhang H, Kavishwar A, Lynes M, Brownell AL, Sun H, Tseng YH, Moore A, Ran C. Curcumin analogues as selective fluorescence imaging probes for brown adipose tissue and monitoring browning. Sci Rep 2015; 5:13116. [PMID: 26269357 PMCID: PMC4534785 DOI: 10.1038/srep13116] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Accepted: 07/16/2015] [Indexed: 01/10/2023] Open
Abstract
Manipulation of brown adipose tissue (BAT) and browning of white adipose tissue (WAT) can be promising new approaches to counter metabolic disorder diseases in humans. Imaging probes that could consistently monitor BAT mass and browning of WAT are highly desirable. In the course of our imaging probe screening, we found that BAT could be imaged with curcumin analogues in mice. However, the poor BAT selectivity over WAT and short emissions of the lead probes promoted further lead optimization. Limited uptake mechanism studies suggested that CD36/FAT (fatty acid transporter) probably contributed to the facilitated uptake of the probes. By increasing the stereo-hindrance of the lead compound, we designed CRANAD-29 to extend the emission and increase the facilitated uptake, thus increasing its BAT selectivity. Our data demonstrated that CRANAD-29 had significantly improved selectivity for BAT over WAT, and could be used for imaging BAT mass change in a streptozotocin-induced diabetic mouse model, as well as for monitoring BAT activation under cold exposure. In addition, CRANAD-29 could be used for monitoring the browning of subcutaneous WAT (sWAT) induced by β3-adrenoceptor agonist CL-316, 243.
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Affiliation(s)
- Xueli Zhang
- 1] Molecular Imaging Laboratory, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital/Harvard Medical School, Boston, MA [2] School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China [3] Department of pharmacy, ZhongDa Hospital, Southeast University, Nanjing 210009, China
| | - Yanli Tian
- 1] Molecular Imaging Laboratory, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital/Harvard Medical School, Boston, MA [2] Department of Parasitology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
| | - Hongbin Zhang
- Joslin Diabetes Center, Harvard Medical School, and Harvard Stem Cell Institute, Boston, MA 02215
| | - Amol Kavishwar
- Molecular Imaging Laboratory, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital/Harvard Medical School, Boston, MA
| | - Matthew Lynes
- Joslin Diabetes Center, Harvard Medical School, and Harvard Stem Cell Institute, Boston, MA 02215
| | - Anna-Liisa Brownell
- Molecular Imaging Laboratory, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital/Harvard Medical School, Boston, MA
| | - Hongbin Sun
- School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Yu-Hua Tseng
- Joslin Diabetes Center, Harvard Medical School, and Harvard Stem Cell Institute, Boston, MA 02215
| | - Anna Moore
- Molecular Imaging Laboratory, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital/Harvard Medical School, Boston, MA
| | - Chongzhao Ran
- Molecular Imaging Laboratory, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital/Harvard Medical School, Boston, MA
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Townsend KL, An D, Lynes MD, Huang TL, Zhang H, Goodyear LJ, Tseng YH. Increased mitochondrial activity in BMP7-treated brown adipocytes, due to increased CPT1- and CD36-mediated fatty acid uptake. Antioxid Redox Signal 2013; 19:243-57. [PMID: 22938691 PMCID: PMC3691916 DOI: 10.1089/ars.2012.4536] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
AIMS Brown adipose tissue dissipates chemical energy in the form of heat and regulates triglyceride and glucose metabolism in the body. Factors that regulate fatty acid uptake and oxidation in brown adipocytes have not yet been fully elucidated. Bone morphogenetic protein 7 (BMP7) is a growth factor capable of inducing brown fat mitochondrial biogenesis during differentiation from adipocyte progenitors. Administration of BMP7 to mice also results in increased energy expenditure. To determine if BMP7 is able to affect the mitochondrial activity of mature brown adipocytes, independent of the differentiation process, we delivered BMP7 to mature brown adipocytes and measured mitochondrial activity. RESULTS We found that BMP7 increased mitochondrial activity, including fatty acid oxidation and citrate synthase activity, without increasing the mitochondrial number. This was accompanied by an increase in fatty acid uptake and increased protein expression of CPT1 and CD36, which import fatty acids into the mitochondria and the cell, respectively. Importantly, inhibition of either CPT1 or CD36 resulted in a blunting of the mitochondrial activity of BMP7-treated cells. INNOVATION These findings uncover a novel pathway regulating mitochondrial activities in mature brown adipocytes by BMP7-mediated fatty acid uptake and oxidation. CONCLUSION In conclusion, BMP7 increases mitochondrial activity in mature brown adipocytes via increased fatty acid uptake and oxidation, a process that requires the fatty acid transporters CPT1 and CD36.
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Affiliation(s)
- Kristy L Townsend
- Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts 02215, USA
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9
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Mitchell JR, Saggerson ED. Activities of enzymes of glycerolipid synthesis in brown adipose tissue after treatment of rats with the adrenergic agonists BRL 26830A and phenylephrine, after exposure to cold and in streptozotocin-diabetes. Biochem J 1991; 277 ( Pt 3):665-9. [PMID: 1678597 PMCID: PMC1151294 DOI: 10.1042/bj2770665] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
1. Measurements were made, relative to tissue DNA, of the activities of enzymes of glycerolipid synthesis in homogenates of interscapular brown adipose tissue. These were: mitochondrial and microsomal forms of glycerolphosphate acyltransferase (GPAT), Mg(2+)-dependent phosphatidate phosphohydrolase (PPH) and fatty acyl-CoA synthetase (FAS). 2. In normal animals, 3 days of cold-exposure (4 degrees C) increased all activities. The increase in mitochondrial GPAT activity was particularly pronounced (5-fold). Administration of the beta-adrenergic agonist BRL 26830A mimicked the effect of cold on microsomal GPAT activity. Mitochondrial GPAT, PPH and FAS activities were unresponsive to BRL 26830A. The alpha-adrenergic agonist phenylephrine significantly decreased activities of GPAT and PPH. 3. Streptozotocin-diabetes decreased mitochondrial GPAT activity, but did not abolish the effect of cold to increase this activity or the activity of microsomal GPAT. Diabetes abolished the effect of cold on PPH and FAS activities. 4. The findings are relevant to signals that drive early events in mitochondriogenesis and cell proliferation in brown adipose tissue on exposure to cold.
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Affiliation(s)
- J R Mitchell
- Department of Biochemistry and Molecular Biology, University College London, U.K
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10
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Woodward JA, Saggerson ED. Effects of hypothyroidism and hyperthyroidism on GDP binding to brown-adipocyte mitochondria from rats. Biochem J 1989; 263:341-5. [PMID: 2597106 PMCID: PMC1133435 DOI: 10.1042/bj2630341] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
1. Rats were made hypothyroid by giving them a low-iodine diet with propylthiouracil for 4 weeks, or were made hyperthyroid by injection with tri-iodothyronine (T3) over a 3-day period. 2. Brown adipocytes were isolated from the interscapular depots of these animals or from their euthyroid controls, followed by isolation of mitochondria from the cells. 3. Relative to cell DNA content, hypothyroidism decreased the maximum binding (Bmax.) of [3H]GDP to mitochondria by 50%. T3 treatment increased binding by 37%. 4. These findings, which are discussed in relation to previously observed changes in brown adipose tissue after alteration of thyroid status, suggest that mitochondrial uncoupling for thermogenesis is less or more effective in hypothyroidism or hyperthyroidism respectively.
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Affiliation(s)
- J A Woodward
- Department of Biochemistry, University College London, U.K
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11
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Gualberto A, Saggerson ED. Differentiation of rapid and slower-acting effects of insulin on mitochondrial processes in brown adipose tissue from streptozotocin-diabetic rats. Biochem J 1989; 258:309-11. [PMID: 2649091 PMCID: PMC1138357 DOI: 10.1042/bj2580309] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Insulin treatment of streptozotocin-diabetic rats restores the depressed palmitoyl-group oxidation observed in brown-adipose-tissue mitochondria from diabetic rats. A relatively rapid effect of insulin (5 h) to increase carnitine-dependent oxidation of palmitoyl-CoA and to increase overt carnitine palmitoyltransferase activity is differentiated from a slower effect of the hormone (1 day) to increase palmitoylcarnitine oxidation.
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Affiliation(s)
- A Gualberto
- Departmento de Bioquimica, Facultad de Medicina, Universidad de Sevilla, Spain
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12
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Affiliation(s)
- J Himms-Hagen
- Department of Biochemistry, University of Ottawa, Ontario, Canada
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13
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Chan BL, Lisanti MP, Rodriguez-Boulan E, Saltiel AR. Insulin-stimulated release of lipoprotein lipase by metabolism of its phosphatidylinositol anchor. Science 1988. [PMID: 2843987 DOI: 10.1126/science.2843987] [Citation(s) in RCA: 123] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Lipoprotein lipase (LPL) plays a critical role in the metabolism of plasma lipoproteins. In 3T3-L1 adipocytes, insulin elicits the rapid release of LPL through mechanisms that are independent of energy metabolism and protein synthesis. Some of the metabolic actions of insulin may be mediated by the activation of a specific phospholipase that hydrolyzes a glycosyl phosphatidylinositol (PI) molecule. The insulin-sensitive glycosyl-PI is structurally similar to the glycolipid membrane anchor of a number of proteins. LPL appears to be anchored to the 3T3-L1 cell surface by glycosyl-PI, and its rapid release by insulin may be due to activation of a glycosyl-PI-specific phospholipase C.
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Affiliation(s)
- B L Chan
- Laboratory of Biochemical Endocrinology, Rockefeller University, New York, NY 10021
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