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Han Y, Sun Q, Chen W, Gao Y, Ye J, Chen Y, Wang T, Gao L, Liu Y, Yang Y. New advances of adiponectin in regulating obesity and related metabolic syndromes. J Pharm Anal 2024; 14:100913. [PMID: 38799237 PMCID: PMC11127227 DOI: 10.1016/j.jpha.2023.12.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 11/18/2023] [Accepted: 12/07/2023] [Indexed: 05/29/2024] Open
Abstract
Obesity and related metabolic syndromes have been recognized as important disease risks, in which the role of adipokines cannot be ignored. Adiponectin (ADP) is one of the key adipokines with various beneficial effects, including improving glucose and lipid metabolism, enhancing insulin sensitivity, reducing oxidative stress and inflammation, promoting ceramides degradation, and stimulating adipose tissue vascularity. Based on those, it can serve as a positive regulator in many metabolic syndromes, such as type 2 diabetes (T2D), cardiovascular diseases, non-alcoholic fatty liver disease (NAFLD), sarcopenia, neurodegenerative diseases, and certain cancers. Therefore, a promising therapeutic approach for treating various metabolic diseases may involve elevating ADP levels or activating ADP receptors. The modulation of ADP genes, multimerization, and secretion covers the main processes of ADP generation, providing a comprehensive orientation for the development of more appropriate therapeutic strategies. In order to have a deeper understanding of ADP, this paper will provide an all-encompassing review of ADP.
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Affiliation(s)
- Yanqi Han
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
- Beijing Key laboratory of Drug Delivery Technology and Novel Formulation, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Qianwen Sun
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
- Beijing Key laboratory of Drug Delivery Technology and Novel Formulation, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Wei Chen
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
- Beijing Key laboratory of Drug Delivery Technology and Novel Formulation, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Yue Gao
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
- Beijing Key laboratory of Drug Delivery Technology and Novel Formulation, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Jun Ye
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
- Beijing Key laboratory of Drug Delivery Technology and Novel Formulation, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Yanmin Chen
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
- Beijing Key laboratory of Drug Delivery Technology and Novel Formulation, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Tingting Wang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
- Beijing Key laboratory of Drug Delivery Technology and Novel Formulation, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Lili Gao
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
- Beijing Key laboratory of Drug Delivery Technology and Novel Formulation, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Yuling Liu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
- Beijing Key laboratory of Drug Delivery Technology and Novel Formulation, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
| | - Yanfang Yang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
- Beijing Key laboratory of Drug Delivery Technology and Novel Formulation, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050, China
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Bauzá-Thorbrügge M, Banke E, Chanclón B, Peris E, Wu Y, Musovic S, Jönsson C, Strålfors P, Rorsman P, Olofsson CS, Asterholm IW. Adipocyte-specific ablation of the Ca 2+ pump SERCA2 impairs whole-body metabolic function and reveals the diverse metabolic flexibility of white and brown adipose tissue. Mol Metab 2022; 63:101535. [PMID: 35760318 PMCID: PMC9287368 DOI: 10.1016/j.molmet.2022.101535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 06/21/2022] [Accepted: 06/22/2022] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE Sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) transports Ca2+ from the cytosol into the ER and is essential for appropriate regulation of intracellular Ca2+ homeostasis. The objective of this study was to test the hypothesis that SERCA pumps are involved in the regulation of white adipocyte hormone secretion and other aspects of adipose tissue function and that this control is disturbed in obesity-induced type-2 diabetes. METHODS SERCA expression was measured in isolated human and mouse adipocytes as well as in whole mouse adipose tissue by Western blot and RT-qPCR. To test the significance of SERCA2 in adipocyte functionality and whole-body metabolism, we generated adipocyte-specific SERCA2 knockout mice. The mice were metabolically phenotyped by glucose tolerance and tracer studies, histological analyses, measurements of glucose-stimulated insulin release in isolated islets, and gene/protein expression analyses. We also tested the effect of pharmacological SERCA inhibition and genetic SERCA2 ablation in cultured adipocytes. Intracellular and mitochondrial Ca2+ levels were recorded with dual-wavelength ratio imaging and mitochondrial function was assessed by Seahorse technology. RESULTS We demonstrate that SERCA2 is downregulated in white adipocytes from patients with obesity and type-2 diabetes as well as in adipocytes from diet-induced obese mice. SERCA2-ablated adipocytes display disturbed Ca2+ homeostasis associated with upregulated ER stress markers and impaired hormone release. These adipocyte alterations are linked to mild lipodystrophy, reduced adiponectin levels, and impaired glucose tolerance. Interestingly, adipocyte-specific SERCA2 ablation leads to increased glucose uptake in white adipose tissue while glucose uptake is reduced in brown adipose tissue. This dichotomous effect on glucose uptake is due to differently regulated mitochondrial function. In white adipocytes, SERCA2 deficiency triggers an adaptive increase in FGF21, increased mitochondrial UCP1 levels, and increased oxygen consumption rate (OCR). In contrast, brown SERCA2 null adipocytes display reduced OCR despite increased mitochondrial content and UCP1 levels compared to wild type controls. CONCLUSIONS Our data suggest causal links between reduced white adipocyte SERCA2 levels, deranged adipocyte Ca2+ homeostasis, adipose tissue dysfunction and type-2 diabetes.
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Affiliation(s)
- Marco Bauzá-Thorbrügge
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30 Göteborg, Sweden.
| | - Elin Banke
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30 Göteborg, Sweden.
| | - Belén Chanclón
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30 Göteborg, Sweden.
| | - Eduard Peris
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30 Göteborg, Sweden.
| | - Yanling Wu
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30 Göteborg, Sweden.
| | - Saliha Musovic
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30 Göteborg, Sweden.
| | - Cecilia Jönsson
- Department of Biomedical and Clinical Sciences, Linköping University, SE-58185 Linköping, Sweden.
| | - Peter Strålfors
- Department of Biomedical and Clinical Sciences, Linköping University, SE-58185 Linköping, Sweden.
| | - Patrik Rorsman
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30 Göteborg, Sweden; Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine, University of Oxford, Oxford OX4 7LE, UK.
| | - Charlotta S Olofsson
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30 Göteborg, Sweden.
| | - Ingrid Wernstedt Asterholm
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30 Göteborg, Sweden.
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Musovic S, Komai AM, Said MK, Shrestha MM, Wu Y, Wernstedt Asterholm I, Olofsson CS. Noradrenaline and ATP regulate adiponectin exocytosis in white adipocytes: Disturbed adrenergic and purinergic signalling in obese and insulin-resistant mice. Mol Cell Endocrinol 2022; 549:111619. [PMID: 35337901 DOI: 10.1016/j.mce.2022.111619] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 02/26/2022] [Accepted: 03/10/2022] [Indexed: 01/19/2023]
Abstract
White adipocyte adiponectin exocytosis is triggered by cAMP and a concomitant increase of cytosolic Ca2+ potentiates its release. White adipose tissue is richly innervated by sympathetic nerves co-releasing noradrenaline (NA) and ATP, which may act on receptors in the adipocyte plasma membrane to increase cAMP via adrenergic receptors and Ca2+ via purinergic receptors. Here we determine the importance of NA and ATP for the regulation of white adipocyte adiponectin exocytosis, at the cellular and molecular level, and we specifically detail the ATP signalling pathway. We demonstrate that tyrosine hydroxylase (enzyme involved in catecholamine synthesis) is dramatically reduced in inguinal white adipose tissue (IWAT) isolated from mice with diet-induced obesity; this is associated with diminished levels of NA in IWAT and with a reduced ratio of high-molecular-weight (HMW) to total adiponectin in serum. Adiponectin exocytosis (measured as an increase in plasma membrane capacitance and as secreted product) is triggered by NA or ATP alone in cultured and primary mouse IWAT adipocytes, and enhanced by a combination of the two secretagogues. The ATP-induced adiponectin exocytosis is largely Ca2+-dependent and activated via purinergic P2Y2 receptors (P2Y2Rs) and the Gq11/PLC pathway. Adiponectin release induced by the nucleotide is abrogated in adipocytes isolated from obese and insulin-resistant mice, and this is associated with ∼70% reduced abundance of P2Y2Rs. The NA-triggered adiponectin exocytosis is likewise abolished in "obese adipocytes", concomitant with a 50% lower gene expression of beta 3 adrenergic receptors (β3ARs). An increase in intracellular Ca2+ is not required for the NA-stimulated adiponectin secretion. Collectively, our data suggest that sympathetic innervation is a principal regulator of adiponectin exocytosis and that disruptions of this control are associated with the obesity-associated reduction of circulating levels of HMW/total adiponectin.
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Affiliation(s)
- Saliha Musovic
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30, Göteborg, Sweden
| | - Ali M Komai
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30, Göteborg, Sweden
| | - Marina Kalds Said
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30, Göteborg, Sweden
| | - Man Mohan Shrestha
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30, Göteborg, Sweden
| | - Yanling Wu
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30, Göteborg, Sweden
| | - Ingrid Wernstedt Asterholm
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30, Göteborg, Sweden
| | - Charlotta S Olofsson
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30, Göteborg, Sweden.
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A systems biology analysis of adrenergically stimulated adiponectin exocytosis in white adipocytes. J Biol Chem 2021; 297:101221. [PMID: 34597667 PMCID: PMC8564731 DOI: 10.1016/j.jbc.2021.101221] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 09/10/2021] [Accepted: 09/20/2021] [Indexed: 01/04/2023] Open
Abstract
Circulating levels of the adipocyte hormone adiponectin are typically reduced in obesity, and this deficiency has been linked to metabolic diseases. It is thus important to understand the mechanisms controlling adiponectin exocytosis. This understanding is hindered by the high complexity of both the available data and the underlying signaling network. To deal with this complexity, we have previously investigated how different intracellular concentrations of Ca2+, cAMP, and ATP affect adiponectin exocytosis, using both patch-clamp recordings and systems biology mathematical modeling. Recent work has shown that adiponectin exocytosis is physiologically triggered via signaling pathways involving adrenergic β3 receptors (β3ARs). Therefore, we developed a mathematical model that also includes adiponectin exocytosis stimulated by extracellular epinephrine or the β3AR agonist CL 316243. Our new model is consistent with all previous patch-clamp data as well as new data (collected from stimulations with a combination of the intracellular mediators and extracellular adrenergic stimuli) and can predict independent validation data. We used this model to perform new in silico experiments where corresponding wet lab experiments would be difficult to perform. We simulated adiponectin exocytosis in single cells in response to the reduction of β3ARs that is observed in adipocytes from animals with obesity-induced diabetes. Finally, we used our model to investigate intracellular dynamics and to predict both cAMP levels and adiponectin release by scaling the model from single-cell to a population of cells-predictions corroborated by experimental data. Our work brings us one step closer to understanding the intricate regulation of adiponectin exocytosis.
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Adiponectin and Asthma: Knowns, Unknowns and Controversies. Int J Mol Sci 2021; 22:ijms22168971. [PMID: 34445677 PMCID: PMC8396527 DOI: 10.3390/ijms22168971] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 08/11/2021] [Accepted: 08/16/2021] [Indexed: 12/14/2022] Open
Abstract
Adiponectin is an adipokine associated with the healthy obese phenotype. Adiponectin increases insulin sensitivity and has cardio and vascular protection actions. Studies related to adiponectin, a modulator of the innate and acquired immunity response, have suggested a role of this molecule in asthma. Studies based on various asthma animal models and on the key cells involved in the allergic response have provided important insights about this relation. Some of them indicated protection and others reversed the balance towards negative effects. Many of them described the cellular pathways activated by adiponectin, which are potentially beneficial for asthma prevention or for reduction in the risk of exacerbations. However, conclusive proofs about their efficiency still need to be provided. In this article, we will, briefly, present the general actions of adiponectin and the epidemiological studies supporting the relation with asthma. The main focus of the current review is on the mechanisms of adiponectin and the impact on the pathobiology of asthma. From this perspective, we will provide arguments for and against the positive influence of this molecule in asthma, also indicating the controversies and sketching out the potential directions of research to complete the picture.
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Musovic S, Shrestha MM, Komai AM, Olofsson CS. Resistin is co-secreted with adiponectin in white mouse adipocytes. Biochem Biophys Res Commun 2020; 534:707-713. [PMID: 33261886 DOI: 10.1016/j.bbrc.2020.11.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 11/04/2020] [Indexed: 12/19/2022]
Abstract
In the current work we have investigated the cellular and molecular regulation of resistin secretion in cultured and primary mouse adipocytes. Resistin is an adipose tissue hormone proposed to contribute to metabolic disease. In rodents, resistin is secreted from white adipocytes whereas it is in humans synthesised and released from other cell types within white adipose tissue. The metabolic importance of resistin has been studied in both mouse and man, but the regulation of its release remains poorly investigated. Here we define that, in mouse adipocytes, resistin secretion is triggered by an intracellular elevation of cAMP and/or Ca2+. Resistin release is stimulated via activation of beta 3 adrenergic receptors (β3ARs) and the downstream signalling protein exchange protein activated by cAMP (Epac). The secretion of resistin is markedly abrogated in adipocytes isolated from obese and diabetic mice. Immunocytochemical staining demonstrates a significant overlap between signals for resistin and the adipocyte hormone adiponectin. Our data propose that resistin and adiponectin are contained within the same vesicles in mouse adipocytes and that the two hormones are co-secreted in response to the same exocytosis-triggering signals.
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Affiliation(s)
- Saliha Musovic
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30, Göteborg, Sweden
| | - Man Mohan Shrestha
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30, Göteborg, Sweden
| | - Ali M Komai
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30, Göteborg, Sweden
| | - Charlotta S Olofsson
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30, Göteborg, Sweden.
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Marino N, German R, Rao X, Simpson E, Liu S, Wan J, Liu Y, Sandusky G, Jacobsen M, Stoval M, Cao S, Storniolo AMV. Upregulation of lipid metabolism genes in the breast prior to cancer diagnosis. NPJ Breast Cancer 2020; 6:50. [PMID: 33083529 PMCID: PMC7538898 DOI: 10.1038/s41523-020-00191-8] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 08/26/2020] [Indexed: 12/12/2022] Open
Abstract
Histologically normal tissue adjacent to the tumor can provide insight of the microenvironmental alterations surrounding the cancerous lesion and affecting the progression of the disease. However, little is known about the molecular changes governing cancer initiation in cancer-free breast tissue. Here, we employed laser microdissection and whole-transcriptome profiling of the breast epithelium prior to and post tumor diagnosis to identify the earliest alterations in breast carcinogenesis. Furthermore, a comprehensive analysis of the three tissue compartments (microdissected epithelium, stroma, and adipose tissue) was performed on the breast donated by either healthy subjects or women prior to the clinical manifestation of cancer (labeled "susceptible normal tissue"). Although both susceptible and healthy breast tissues appeared histologically normal, the susceptible breast epithelium displayed a significant upregulation of genes involved in fatty acid uptake/transport (CD36 and AQP7), lipolysis (LIPE), and lipid peroxidation (AKR1C1). Upregulation of lipid metabolism- and fatty acid transport-related genes was observed also in the microdissected susceptible stromal and adipose tissue compartments, respectively, when compared with the matched healthy controls. Moreover, inter-compartmental co-expression analysis showed increased epithelium-adipose tissue crosstalk in the susceptible breasts as compared with healthy controls. Interestingly, reductions in natural killer (NK)-related gene signature and CD45+/CD20+ cell staining were also observed in the stromal compartment of susceptible breasts. Our study yields new insights into the cancer initiation process in the breast. The data suggest that in the early phase of cancer development, metabolic activation of the breast, together with increased epithelium-adipose tissue crosstalk may create a favorable environment for final cell transformation, proliferation, and survival.
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Affiliation(s)
- Natascia Marino
- Susan G. Komen Tissue Bank at the IU Simon Cancer Center, Indianapolis, IN 46202 USA
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | - Rana German
- Susan G. Komen Tissue Bank at the IU Simon Cancer Center, Indianapolis, IN 46202 USA
| | - Xi Rao
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | - Ed Simpson
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | - Sheng Liu
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | - Jun Wan
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | - Yunlong Liu
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | - George Sandusky
- Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | - Max Jacobsen
- Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | - Miranda Stoval
- Susan G. Komen Tissue Bank at the IU Simon Cancer Center, Indianapolis, IN 46202 USA
| | - Sha Cao
- Department of Biostatistics, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | - Anna Maria V Storniolo
- Susan G. Komen Tissue Bank at the IU Simon Cancer Center, Indianapolis, IN 46202 USA
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN 46202 USA
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8
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Inoue H, Inazu M, Konishi M, Yokoyama U. Functional expression of TRPM7 as a Ca 2+ influx pathway in adipocytes. Physiol Rep 2020; 7:e14272. [PMID: 31650715 PMCID: PMC6813326 DOI: 10.14814/phy2.14272] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2019] [Revised: 09/20/2019] [Accepted: 10/04/2019] [Indexed: 02/01/2023] Open
Abstract
In adipocytes, intracellular Ca2+ and Mg2+ modulates physiological functions, such as insulin action and the secretion of adipokines. TRPM7 is a Ca2+/Mg2+‐permeable non‐selective cation channel. TRPM7 mRNA is highly expressed in adipose tissue, however, its functional expression in adipocytes remains to be elucidated. In this study, we demonstrated for the first time that TRPM7 was functionally expressed in both freshly isolated white adipocytes and in 3T3‐L1 adipocytes differentiated from a 3T3‐L1 pre‐adipocyte cell line by whole‐cell patch‐clamp recordings. Consistent with known properties of TRPM7 current, the current in adipocytes was activated by the elimination of extracellular divalent cations and the reduction of intracellular free Mg2+ concentrations, and was inhibited by the TRPM7 inhibitors, 2‐aminoethyl diphenylborinate (2‐APB), hydrogen peroxide (H2O2), N‐methyl maleimide (NMM), NS8593, and 2‐amino‐2‐[2‐(4‐octylphenyl)ethyl]‐1,3‐propanediol (FTY720). Treatment with small‐interfering (si) RNA targeting TRPM7 resulted in a reduction in the current to 23 ± 7% of nontargeting siRNA‐treated adipocytes. Moreover a TRPM7 activator, naltriben, increased the TRPM7‐like current and [Ca2+]i in 3T3‐L1 adipocytes but not in TRPM7‐knockdown adipocytes. These findings indicate that TRPM7 is functionally expressed, and plays a role as a Ca2+ influx pathway in adipocytes.
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Affiliation(s)
- Hana Inoue
- Department of Physiology, Tokyo Medical University, Tokyo, Japan
| | - Masato Inazu
- Institute of Medical Science, Tokyo Medical University, Tokyo, Japan
| | - Masato Konishi
- Department of Physiology, Tokyo Medical University, Tokyo, Japan
| | - Utako Yokoyama
- Department of Physiology, Tokyo Medical University, Tokyo, Japan
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Hu J, Li X, Judd RL, Easley CJ. Rapid lipolytic oscillations in ex vivo adipose tissue explants revealed through microfluidic droplet sampling at high temporal resolution. LAB ON A CHIP 2020; 20:1503-1512. [PMID: 32239045 PMCID: PMC7380261 DOI: 10.1039/d0lc00103a] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Our understanding of adipose tissue biology has steadily evolved. While structural and energy storage functionalities have been in the forefront, a key endocrine role for adipocytes was revealed only over the last few decades. In contrast to the wealth of information on dynamic function of other endocrine tissues, few studies have focused on dynamic adipose tissue function or on tool development toward that end. Here, we apply our unique droplet-based microfluidic devices to culture, perfuse, and sample secretions from primary murine epididymal white adipose tissue (eWAT), and from predifferentiated clusters of 3T3-L1 adipocytes. Through automated control, oil-segmented aqueous droplets (∼2.6 nL) were sampled from tissue or cells at 3.5 second temporal resolution (including sample and reference droplets), with integrated enzyme assays enabling real-time quantification of glycerol (down to 1.9 fmol per droplet). This high resolution revealed previously unreported oscillations in secreted glycerol at frequencies of 0.2 to 2.0 min-1 (∼30-300 s periods) present in the primary tissue but not in clustered cells. Low-level bursts (∼50 fmol) released in basal conditions were contrasted with larger bursts (∼300 fmol) during stimulation. Further, both fold changes and burst magnitudes were decreased in eWAT of aged and obese mice. These results, combined with immunostaining and photobleaching analyses, suggest that gap-junctional coupling or nerve cell innervation within the intact ex vivo tissue explants play important roles in this apparent tissue-level, lipolytic synchronization. High-resolution, quantitative sampling by droplet microfluidics thus permitted unique biological information to be observed, giving an analytical framework poised for future studies of dynamic oscillatory function of adipose and other tissues.
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Affiliation(s)
- Juan Hu
- Department of Chemistry and Biochemistry, Auburn University, Auburn, AL 36849, USA.
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Adrenergic stimulation of adiponectin secretion in visceral mouse adipocytes is blunted in high-fat diet induced obesity. Sci Rep 2019; 9:10680. [PMID: 31337827 PMCID: PMC6650418 DOI: 10.1038/s41598-019-47113-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 07/09/2019] [Indexed: 12/31/2022] Open
Abstract
The hormone adiponectin is secreted by white adipocytes and has been put forward as a key mediator of obesity-linked insulin resistance and the metabolic syndrome. Although adiponectin was discovered two decades ago, the knowledge about the molecular and cellular regulation of its secretion is incomplete. Here we have investigated the adrenergic regulation of adiponectin secretion in primary visceral (gonadal) adipocytes isolated from lean or obese/diabetic mice. We show that visceral adipocyte adiponectin release is triggered by cAMP/catecholamines via signalling pathways involving adrenergic beta-3-receptors (β3ARs) and Exchange Protein directly Activated by cAMP, isoform 1 (Epac1). The adrenergically stimulated adiponectin secretion is blunted in visceral adipocytes isolated from obese and diabetic mice and our results suggest the existence of a secretory defect. We have previously shown that adiponectin secretion in subcutaneous adipocytes is abolished in the obese/diabetic state due to reduced abundance of β3ARs and Epac1. However, here we show that protein levels of β3ARs and Epac1 are maintained in visceral adipocytes from obese/diabetic mice proposing that other molecular defects underlie the blunted adiponectin release. Gene expression analysis indicate diabesity-associated disturbances of the signalling downstream of Epac1 and/or the exocytotic process itself. Our study proposes that visceral adipocytes partake in the regulated secretion of adiponectin and may thus influence circulating levels of the hormone, in health and in metabolic disease.
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Quantitative Mapping of Triacylglycerol Chain Length and Saturation Using Broadband CARS Microscopy. Biophys J 2019; 116:2346-2355. [PMID: 31153590 DOI: 10.1016/j.bpj.2019.04.036] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 03/25/2019] [Accepted: 04/25/2019] [Indexed: 01/15/2023] Open
Abstract
Lipid droplets (LDs), present in many cell types, are highly dynamic organelles that store neutral lipids, primarily triacylglycerols (TAGs). With the discovery of new LD functions (e.g., in immune response, protein clearage, and occurrence with disease), new methods to study LD chemical composition in situ are necessary. We present an approach for in situ, quantitative TAG analysis using label-free, coherent Raman microscopy that allows deciphering LD TAG composition in different biochemically complex samples with submicrometer spatial resolution. Employing a set of standard TAGs, we generate a spectral training matrix capturing the variation caused in Raman-like spectra by TAG backbone, chain length, and number of double bonds per chain, as well as the presence of proteins or other diluting molecules. Comparing our fitting approach to gas chromatography measurements for mixtures of standard TAGs and food oils, we find the root mean-square error for the prediction of TAG chemistry to be 0.69 CH2 and 0.15 #C=C. When progressing to more complex samples such as oil emulsions and LDs in various eukaryotic cells, we find good agreement with bulk gas chromatography measurements. For differentiated adipocytes, we find a significant increase in the number of double bonds in small LDs (below 2 μm in diameter) compared to large LDs (above 2 μm in diameter). Coupled with a relatively limited sample preparation requirement, this approach should enable rapid and accurate TAG LD analysis for a variety of cell biology and technological applications.
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12
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Al-Anazi A, Parhar R, Saleh S, Al-Hijailan R, Inglis A, Al-Jufan M, Bazzi M, Hashmi S, Conca W, Collison K, Al-Mohanna F. Intracellular calcium and NF- kB regulate hypoxia-induced leptin, VEGF, IL-6 and adiponectin secretion in human adipocytes. Life Sci 2018; 212:275-284. [PMID: 30308181 DOI: 10.1016/j.lfs.2018.10.014] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Revised: 09/19/2018] [Accepted: 10/06/2018] [Indexed: 11/26/2022]
Abstract
AIMS Hypoxia-induced adipokine release has been attributed mainly to HIF-1α. Here we investigate the role of intracellular calcium and NF-kB in the hypoxia-dependent release of leptin, VEGF, IL-6 and the hypoxia-induced inhibition of adiponectin release in human adipocytes. MAIN METHODS We used intracellular calcium imaging to compare calcium status in preadipocytes and in adipocytes. We subjected both cell types to hypoxic conditions and measured the release of adipokines induced by hypoxia in the presence and absence of HIF-1α inhibitor YC-1, NF-κB inhibitor SN50 and intracellular calcium chelator BAPTA-AM. KEY FINDINGS We demonstrate reduced intracellular calcium oscillations and increased oxidative stress as the cells transitioned from preadipocytes to adipocytes. We show that differentiation of preadipocytes to adipocytes is associated with distinct morphological changes in the mitochondria. We also show that hypoxia-induced secretion of leptin, VEGF, IL-6 and hypoxia-induced inhibition of adiponectin secretion are independent of HIF-1α expression. The hypoxia-induced leptin, VEGF and IL-6 release are [Ca++]i dependent whereas adiponectin is NF-kB dependent. SIGNIFICANCE Our work suggests a major role for [Ca++]i in preadipocyte differentiation to adipocytes and that changes in mitochondrial morphology in the adipocytes might underlie the reduced calcium oscillations observed in the adipocytes. It also demonstrates that multiple signaling pathways are associated with the hypoxia-induced adipokine secretion.
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Affiliation(s)
- Azizah Al-Anazi
- Department of Cell Biology, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia
| | - Ranjit Parhar
- Department of Cell Biology, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia
| | - Soad Saleh
- Department of Cell Biology, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia
| | - Reem Al-Hijailan
- Department of Cell Biology, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia
| | - Angela Inglis
- Department of Cell Biology, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia
| | - Mansour Al-Jufan
- Heart Centre, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia
| | - Mohammed Bazzi
- Department of Biochemistry, College of Science, King Saud University, Riyadh 12372, Saudi Arabia
| | - Sarwar Hashmi
- Developmental Biology, Center for Vector Biology, Rutgers University, New Brunswick, NJ 08901, United States
| | - Walter Conca
- Department of Cell Biology, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia; Department of Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia; College of Medicine, Alfaisal University, Riyadh 11211, Saudi Arabia
| | - Kate Collison
- Department of Cell Biology, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia
| | - Futwan Al-Mohanna
- Department of Cell Biology, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia; College of Medicine, Alfaisal University, Riyadh 11211, Saudi Arabia.
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13
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Abstract
Adiponectin circulates in blood in multiple isoforms. High molecular weight (HMW) adiponectin is thought to be most biologically active and promotes glucose uptake, insulin sensitivity, and fatty acid oxidation. In obesity, adiponectin isoform formation is disrupted, leading to an inverse association between metabolic disease and HMW and total adiponectin. Adiponectin isoforms also function as acute-phase reactants influencing inflammation in acute and chronic disease. Interestingly, adiponectin and mortality have a U-shaped association. Unfortunately, data concerning adiponectin and its pathophysiologic function conflict. This is predominantly due to difficulties in adequate measurement of adiponectin isoforms and lack of a gold standard. In this review we provide a general overview of the formation and function of adiponectin and its isoforms under physiologic conditions. We highlight the ways adiponectin isoform formation is disrupted in obesity and its ensuing pathologic conditions. Furthermore, we will elaborate on the role of adiponectin isoforms as inflammatory proteins with respect to cardiac and kidney disease and discuss the association of adiponectin with mortality. Finally, we will provide a historical perspective on the measurement of adiponectin isoforms, current limitations, and future challenges.
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Affiliation(s)
| | - Annemieke C Heijboer
- VU University Medical Center, Amsterdam, The Netherlands; Academic Medical Center, Amsterdam, The Netherlands
| | - Madeleine L Drent
- VU University Medical Center, Amsterdam, The Netherlands; VU University, Amsterdam, The Netherlands
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14
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El Hachmane MF, Olofsson CS. A mechanically activated TRPC1-like current in white adipocytes. Biochem Biophys Res Commun 2018. [PMID: 29524421 DOI: 10.1016/j.bbrc.2018.03.050] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Ca2+ impacts a large array of cellular processes in every known cell type. In the white adipocyte, Ca2+ is involved in regulation of metabolic processes such as lipolysis, glucose uptake and hormone secretion. Although the importance of Ca2+ in control of white adipocyte function is clear, knowledge is still lacking regarding the control of dynamic Ca2+ alterations within adipocytes and mechanisms inducing intracellular Ca2+ changes remain elusive. Own work has recently demonstrated the existence of store-operated Ca2+ entry (SOCE) in lipid filled adipocytes. We defined stromal interaction molecule 1 (STIM1) and the calcium release-activated calcium channel protein 1 (ORAI1) as the key players involved in this process and we showed that the transient receptor potential (TRP) channel TRPC1 contributed to SOCE. Here we have aimed to further characterised SOCE in the white adipocyte by use of single cell whole-cell patch clamp recordings. The electrophysiological measurements show the existence of a seemingly constitutively active current that is inhibited by known store-operated Ca2+ channel (SOCC) blockers. We demonstrate that the mechanical force applied to the plasma membrane upon patching leads to an elevation of the cytoplasmic Ca2+ concentration and that this elevation can be reversed by SOCC antagonists. We conclude that a mechanically activated current with properties similar to TRPC1 is present in white adipocytes. Activation of TRPC1 by membrane tension/stretch may be specifically important for the function of this cell type, since adipocytes can rapidly increase or decrease in size.
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Affiliation(s)
- Mickaël F El Hachmane
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Medicinaregatan 11, SE-405 30, Göteborg, Sweden
| | - Charlotta S Olofsson
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Medicinaregatan 11, SE-405 30, Göteborg, Sweden.
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15
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Extracellular ATP activates store-operated Ca 2+ entry in white adipocytes: functional evidence for STIM1 and ORAI1. Biochem J 2018; 475:691-704. [PMID: 29335300 PMCID: PMC5813502 DOI: 10.1042/bcj20170484] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Revised: 01/05/2018] [Accepted: 01/13/2018] [Indexed: 12/26/2022]
Abstract
In the present study, we have applied ratiometric measurements of intracellular Ca2+ concentrations ([Ca2+]i) to show that extracellularly applied ATP (adenosine triphosphate) (100 µM) stimulates store-operated Ca2+ entry (SOCE) in 3T3-L1 adipocytes. ATP produced a rapid increase in [Ca2+]i consisting of an initial transient elevation followed by a sustained elevated phase that could be observed only in the presence of extracellular Ca2+. Gene expression data and [Ca2+]i recordings with uridine-5′-triphosphate or with the phospholipase C (PLC) inhibitor U73122 demonstrated the involvement of purinergic P2Y2 receptors and the PLC/inositol trisphosphate pathway. The [Ca2+]i elevation produced by reintroduction of a Ca2+-containing intracellular solution to adipocytes exposed to ATP in the absence of Ca2+ was diminished by known SOCE antagonists. The chief molecular components of SOCE, the stromal interaction molecule 1 (STIM1) and the calcium release-activated calcium channel protein 1 (ORAI1), were detected at the mRNA and protein level. Moreover, SOCE was largely diminished in cells where STIM1 and/or ORAI1 had been silenced by small interfering (si)RNA. We conclude that extracellular ATP activates SOCE in white adipocytes, an effect predominantly mediated by STIM1 and ORAI1.
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16
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Brännmark C, Lövfors W, Komai AM, Axelsson T, El Hachmane MF, Musovic S, Paul A, Nyman E, Olofsson CS. Mathematical modeling of white adipocyte exocytosis predicts adiponectin secretion and quantifies the rates of vesicle exo- and endocytosis. J Biol Chem 2017; 292:20032-20043. [PMID: 28972187 DOI: 10.1074/jbc.m117.801225] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 09/22/2017] [Indexed: 11/06/2022] Open
Abstract
Adiponectin is a hormone secreted from white adipocytes and takes part in the regulation of several metabolic processes. Although the pathophysiological importance of adiponectin has been thoroughly investigated, the mechanisms controlling its release are only partly understood. We have recently shown that adiponectin is secreted via regulated exocytosis of adiponectin-containing vesicles, that adiponectin exocytosis is stimulated by cAMP-dependent mechanisms, and that Ca2+ and ATP augment the cAMP-triggered secretion. However, much remains to be discovered regarding the molecular and cellular regulation of adiponectin release. Here, we have used mathematical modeling to extract detailed information contained within our previously obtained high-resolution patch-clamp time-resolved capacitance recordings to produce the first model of adiponectin exocytosis/secretion that combines all mechanistic knowledge deduced from electrophysiological experimental series. This model demonstrates that our previous understanding of the role of intracellular ATP in the control of adiponectin exocytosis needs to be revised to include an additional ATP-dependent step. Validation of the model by introduction of data of secreted adiponectin yielded a very close resemblance between the simulations and experimental results. Moreover, we could show that Ca2+-dependent adiponectin endocytosis contributes to the measured capacitance signal, and we were able to predict the contribution of endocytosis to the measured exocytotic rate under different experimental conditions. In conclusion, using mathematical modeling of published and newly generated data, we have obtained estimates of adiponectin exo- and endocytosis rates, and we have predicted adiponectin secretion. We believe that our model should have multiple applications in the study of metabolic processes and hormonal control thereof.
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Affiliation(s)
- Cecilia Brännmark
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30 Göteborg
| | - William Lövfors
- Departments of Biomedical Engineering, SE-581 83 Linköping; Mathematics, Linköping University, SE-581 83 Linköping
| | - Ali M Komai
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30 Göteborg
| | - Tom Axelsson
- Departments of Biomedical Engineering, SE-581 83 Linköping
| | - Mickaël F El Hachmane
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30 Göteborg
| | - Saliha Musovic
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30 Göteborg
| | - Alexandra Paul
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10 SE-412 96 Göteborg
| | - Elin Nyman
- Departments of Biomedical Engineering, SE-581 83 Linköping; Cardiovascular and Metabolic Diseases iMed Biotech Unit, AstraZeneca R&D, 431 83 Gothenburg, Sweden.
| | - Charlotta S Olofsson
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 11, SE-405 30 Göteborg.
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17
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Krautbauer S, Haberl EM, Eisinger K, Pohl R, Rein-Fischboeck L, Rentero C, Alvarez-Guaita A, Enrich C, Grewal T, Buechler C, Neumeier M. Annexin A6 regulates adipocyte lipid storage and adiponectin release. Mol Cell Endocrinol 2017; 439:419-430. [PMID: 27702590 DOI: 10.1016/j.mce.2016.09.033] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 09/30/2016] [Accepted: 09/30/2016] [Indexed: 12/28/2022]
Abstract
Lipid storage and adipokine secretion are critical features of adipocytes. Annexin A6 (AnxA6) is a lipid-binding protein regulating secretory pathways and its role in adiponectin release was examined. The siRNA-mediated AnxA6 knock-down in 3T3-L1 preadipocytes impaired proliferation, and differentiation of AnxA6-depleted cells to mature adipocytes was associated with higher soluble adiponectin and increased triglyceride storage. The latter was partly attributed to reduced lipolysis. Accordingly, AnxA6 overexpression in 3T3-L1 adipocytes lowered cellular triglycerides and adiponectin secretion. Indeed, serum adiponectin was increased in AnxA6 deficient mice. Expression analysis identified AnxA6 protein to be more abundant in intra-abdominal compared to subcutaneous adipose tissues of mice and men. AnxA6 protein levels increased in white adipose tissues of obese mice and here, levels were highest in subcutaneous fat. AnxA6 protein in adipocytes was upregulated by oxidative stress which might trigger AnxA6 induction in adipose tissues and contribute to impaired fat storage and adiponectin release.
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Affiliation(s)
- Sabrina Krautbauer
- Department of Internal Medicine I, Regensburg University Hospital, 93042 Regensburg, Germany
| | - Elisabeth M Haberl
- Department of Internal Medicine I, Regensburg University Hospital, 93042 Regensburg, Germany
| | - Kristina Eisinger
- Department of Internal Medicine I, Regensburg University Hospital, 93042 Regensburg, Germany
| | - Rebekka Pohl
- Department of Internal Medicine I, Regensburg University Hospital, 93042 Regensburg, Germany
| | - Lisa Rein-Fischboeck
- Department of Internal Medicine I, Regensburg University Hospital, 93042 Regensburg, Germany
| | - Carles Rentero
- Departament de Biologia Cellular, Immunologia i Neurociències, Facultat de Medicina, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Universitat de Barcelona, 08036, Barcelona, Spain
| | - Anna Alvarez-Guaita
- Departament de Biologia Cellular, Immunologia i Neurociències, Facultat de Medicina, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Universitat de Barcelona, 08036, Barcelona, Spain
| | - Carlos Enrich
- Departament de Biologia Cellular, Immunologia i Neurociències, Facultat de Medicina, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Universitat de Barcelona, 08036, Barcelona, Spain
| | - Thomas Grewal
- Faculty of Pharmacy, University of Sydney, Sydney, NSW, 2006, Australia
| | - Christa Buechler
- Department of Internal Medicine I, Regensburg University Hospital, 93042 Regensburg, Germany.
| | - Markus Neumeier
- Department of Internal Medicine I, Regensburg University Hospital, 93042 Regensburg, Germany
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18
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Komai AM, Musovic S, Peris E, Alrifaiy A, El Hachmane MF, Johansson M, Wernstedt Asterholm I, Olofsson CS. White Adipocyte Adiponectin Exocytosis Is Stimulated via β3-Adrenergic Signaling and Activation of Epac1: Catecholamine Resistance in Obesity and Type 2 Diabetes. Diabetes 2016; 65:3301-3313. [PMID: 27554468 DOI: 10.2337/db15-1597] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 08/09/2016] [Indexed: 11/13/2022]
Abstract
We investigated the physiological regulation of adiponectin exocytosis in health and metabolic disease by a combination of membrane capacitance patch-clamp recordings and biochemical measurements of short-term (30-min incubations) adiponectin secretion. Epinephrine or the β3-adrenergic receptor (AR) agonist CL 316,243 (CL) stimulated adiponectin exocytosis/secretion in cultured 3T3-L1 and in primary subcutaneous mouse adipocytes, and the stimulation was inhibited by the Epac (Exchange Protein directly Activated by cAMP) antagonist ESI-09. The β3AR was highly expressed in cultured and primary adipocytes, whereas other ARs were detected at lower levels. 3T3-L1 and primary adipocytes expressed Epac1, whereas Epac2 was undetectable. Adiponectin secretion could not be stimulated by epinephrine or CL in adipocytes isolated from obese/type 2 diabetic mice, whereas the basal (unstimulated) adiponectin release level was elevated twofold. Gene expression of β3AR and Epac1 was reduced in adipocytes from obese animals, and corresponded to a respective ∼35% and ∼30% reduction at the protein level. Small interfering RNA-mediated knockdown of β3AR (∼60%) and Epac1 (∼50%) was associated with abrogated catecholamine-stimulated adiponectin secretion. We propose that adiponectin exocytosis is stimulated via adrenergic signaling pathways mainly involving β3ARs. We further suggest that adrenergically stimulated adiponectin secretion is disturbed in obesity/type 2 diabetes as a result of the reduced expression of β3ARs and Epac1 in a state we define as "catecholamine resistance."
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Affiliation(s)
- Ali M Komai
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden
| | - Saliha Musovic
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden
| | - Eduard Peris
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden
| | - Ahmed Alrifaiy
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden
| | - Mickaël F El Hachmane
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden
| | - Marcus Johansson
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden
| | - Ingrid Wernstedt Asterholm
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden
| | - Charlotta S Olofsson
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden
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