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Liu Y, Yu Z, Wang X, Yuan MQ, Lu MJ, Gong MR, Li Q, Xia YB, Yang GH, Xu B, Litscher G, Xu TC. Neurophysiological mechanisms of electroacupuncture in regulating pancreatic function and adipose tissue expansion. World J Diabetes 2025; 16. [DOI: doi:10.4239/wjd.v16.i5.101354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/15/2025] Open
Abstract
BACKGROUND
Electroacupuncture (EA) has been recognized for its beneficial effects on glucolipid metabolism, potentially through the regulation of sensory nerve coordination. The expandability of peripancreatic adipose tissue (PAT) is implicated in the transition from obesity to type 2 diabetes mellitus (T2DM). However, the specific pancreatic responses to EA require further elucidation.
AIM
To investigate the influence of EA on pancreatic glucolipid reduction level in a high-fat diet (HFD) rat model.
METHODS
To delineate the precise pathway through which EA mediates interactions between PAT and islets, we assessed the expression levels of NGF, TRPV1, insulin, as well as other proteins in the pancreas and PAT. This approach enabled us to identify the acupoints that are most conducive to optimizing glycolipid metabolism.
RESULTS
The ST25, LI11 and ST37 groups attenuated HFD-induced obesity and insulin resistance (IR) to distinct degrees, with ST25 group having the greatest effect. EA at ST25 was found to modify the local regulatory influence of PAT on the pancreatic intrinsic nervous system. Specifically, EA at ST25 obviously activated the TRPV1-CGRP-islet beta cell pathway, contributing to the relief of glucolipid metabolic stress. The beneficial effects were abrogated following the chemical silencing of TRPV1 sensory afferents, confirming their indispensable role in EA-mediated regulation of islet and PAT function. Furthermore, in TRPV1 knockout mice, a reduction in PAT inflammation was observed, along with the recovery of islet beta cell function. EA at LI11 and ST37 demonstrated anti-inflammatory properties and helped ameliorate IR.
CONCLUSION
The PAT ecological niche influenced the progression from obesity to T2DM through various immunometabolic pathways. EA at ST25 could regulate glucolipid metabolism via the TRPV1-CGRP-islet beta cell pathway.
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Liu Y, Yu Z, Wang X, Yuan MQ, Lu MJ, Gong MR, Li Q, Xia YB, Yang GH, Xu B, Litscher G, Xu TC. Neurophysiological mechanisms of electroacupuncture in regulating pancreatic function and adipose tissue expansion. World J Diabetes 2025; 16:101354. [DOI: 10.4239/wjd.v16.i5.101354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2024] [Revised: 02/12/2025] [Accepted: 03/14/2025] [Indexed: 04/25/2025] Open
Abstract
BACKGROUND Electroacupuncture (EA) has been recognized for its beneficial effects on glucolipid metabolism, potentially through the regulation of sensory nerve coordination. The expandability of peripancreatic adipose tissue (PAT) is implicated in the transition from obesity to type 2 diabetes mellitus (T2DM). However, the specific pancreatic responses to EA require further elucidation.
AIM To investigate the influence of EA on pancreatic glucolipid reduction level in a high-fat diet (HFD) rat model.
METHODS To delineate the precise pathway through which EA mediates interactions between PAT and islets, we assessed the expression levels of NGF, TRPV1, insulin, as well as other proteins in the pancreas and PAT. This approach enabled us to identify the acupoints that are most conducive to optimizing glycolipid metabolism.
RESULTS The ST25, LI11 and ST37 groups attenuated HFD-induced obesity and insulin resistance (IR) to distinct degrees, with ST25 group having the greatest effect. EA at ST25 was found to modify the local regulatory influence of PAT on the pancreatic intrinsic nervous system. Specifically, EA at ST25 obviously activated the TRPV1-CGRP-islet beta cell pathway, contributing to the relief of glucolipid metabolic stress. The beneficial effects were abrogated following the chemical silencing of TRPV1 sensory afferents, confirming their indispensable role in EA-mediated regulation of islet and PAT function. Furthermore, in TRPV1 knockout mice, a reduction in PAT inflammation was observed, along with the recovery of islet beta cell function. EA at LI11 and ST37 demonstrated anti-inflammatory properties and helped ameliorate IR.
CONCLUSION The PAT ecological niche influenced the progression from obesity to T2DM through various immunometabolic pathways. EA at ST25 could regulate glucolipid metabolism via the TRPV1-CGRP-islet beta cell pathway.
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Affiliation(s)
- Yun Liu
- Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing 210023, Jiangsu Province, China
| | - Zhi Yu
- Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing 210023, Jiangsu Province, China
| | - Xuan Wang
- College of Traditional Chinese Medicine, Jiangsu Vocational College of Medicine, Yancheng 224000, Jiangsu Province, China
| | - Ming-Qian Yuan
- Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing 210023, Jiangsu Province, China
| | - Meng-Jiang Lu
- Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing 210023, Jiangsu Province, China
| | - Mei-Rong Gong
- Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing 210023, Jiangsu Province, China
| | - Qian Li
- Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing 210023, Jiangsu Province, China
| | - You-Bing Xia
- Affiliated Hospital of Xuzhou Medical University, Xuzhou Medical University, Xuzhou 221004, Jiangsu Province, China
| | - Guan-Hu Yang
- Department of Specialty Medicine, Ohio University, Athens, OH 45701, United States
| | - Bin Xu
- Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing 210023, Jiangsu Province, China
| | - Gerhard Litscher
- High-Tech Acupuncture and Digital Chinese Medicine, Swiss University of Traditional Chinese Medicine, Bad Zurzach 5530, Switzerland
| | - Tian-Cheng Xu
- Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing 210023, Jiangsu Province, China
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Lu M, Yu Z, Yang X, An L, Jing X, Xu T, Yuan M, Xu B, Yu Z. Remodelling the inguinal adipose sensory system to switch on the furnace: Electroacupuncture stimulation induces brown adipose thermogenesis. Diabetes Obes Metab 2024; 26:1430-1442. [PMID: 38229447 DOI: 10.1111/dom.15444] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 12/22/2023] [Accepted: 12/23/2023] [Indexed: 01/18/2024]
Abstract
Brown and white adipose tissue mediate thermogenesis through the thermogenetic centre of the brain, but safe methods for activating thermogensis and knowledge of the associated molecular mechanisms are lacking. We investigated body surface electroacupuncture stimulation (ES) at ST25 (targeted at the abdomen) induction of brown adipose thermogenesis and the neural mechanism of this process. Inguinal white adipose tissue (iWAT) and interscapular brown adipose tissue (iBAT) were collected and the thermogenic protein expression levels were measured to evaluate iBAT thermogenesis capacity. The thermogenic centre activating region and sympathetic outflow were evaluated based on neural electrical activity and c-fos expression levels. iWAT sensory axon plasticity was analysed with whole-mount adipose tissue imaging. ES activated the sympathetic nerves in iBAT and the c-fos-positive cells induced sympathetic outflow activation to the iBAT from the medial preoptic area (MPA), the dorsomedial hypothalamus (DM) and the raphe pallidus nucleus (RPA). iWAT denervation mice exhibited decreased c-fos-positive cells in the DM and RPA, and lower recombinant uncoupling orotein 1 peroxisome proliferator-activated receptor, β3-adrenergic receptor, and tyrosine hydroxylase expression. Remodelling the iWAT sensory axons recovered the signal from the MPA to the RPA and induced iBAT thermogenesis. The sympathetic denervation attenuated sensory nerve density. ES induced sympathetic outflow from the thermogenetic centres to iBAT, which mediated thermogenesis. iWAT sensory axon remodelling induced the MPA-DM-RPA-iBAT thermogenesis pathway.
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Affiliation(s)
- Mengjiang Lu
- Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing, China
| | - Ziwei Yu
- Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing, China
| | - Xingyu Yang
- Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing, China
| | - Li An
- School of Traditional Chinese Medicine, Nanjing University of Chinese Medicine, Nanjing, China
| | - Xinyue Jing
- Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing, China
| | - Tiancheng Xu
- Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing, China
| | - Mengqian Yuan
- Jiangsu Province Hospital of Chinese Medicine, Nanjing, China
| | - Bin Xu
- Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing, China
| | - Zhi Yu
- Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing, China
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4
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Wang Y, Ye L. The Afferent Function of Adipose Innervation. Diabetes 2024; 73:348-354. [PMID: 38377447 PMCID: PMC10882147 DOI: 10.2337/dbi23-0002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Accepted: 12/18/2023] [Indexed: 02/22/2024]
Abstract
Adipose tissue innervation is critical for regulating metabolic and energy homeostasis. While the sympathetic efferent innervation of fat is well characterized, the role of sensory or afferent innervation remains less explored. This article reviews previous work on adipose innervation and recent advances in the study of sensory innervation of adipose tissues. We discuss key open questions, including the physiological implications of adipose afferents in homeostasis as well as potential cross talk with sympathetic neurons, the immune system, and hormonal pathways. We also outline the general technical challenges of studying dorsal root ganglia innervating fat, along with emerging technologies that may overcome these barriers. Finally, we highlight areas for further research to deepen our understanding of the afferent function of adipose innervation.
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Affiliation(s)
- Yu Wang
- Department of Neuroscience and Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA
| | - Li Ye
- Department of Neuroscience and Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA
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Mishra G, Townsend KL. Sensory nerve and neuropeptide diversity in adipose tissues. Mol Cells 2024; 47:100030. [PMID: 38364960 PMCID: PMC10960112 DOI: 10.1016/j.mocell.2024.100030] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 02/06/2024] [Accepted: 02/06/2024] [Indexed: 02/18/2024] Open
Abstract
Both brown and white adipose tissues (BAT/WAT) are innervated by the peripheral nervous system, including efferent sympathetic nerves that communicate from the brain/central nervous system out to the tissue, and afferent sensory nerves that communicate from the tissue back to the brain and locally release neuropeptides to the tissue upon stimulation. This bidirectional neural communication is important for energy balance and metabolic control, as well as maintaining adipose tissue health through processes like browning (development of metabolically healthy brown adipocytes in WAT), thermogenesis, lipolysis, and adipogenesis. Decades of sensory nerve denervation studies have demonstrated the particular importance of adipose sensory nerves for brown adipose tissue and WAT functions, but far less is known about the tissue's sensory innervation compared to the better-studied sympathetic nerves and their neurotransmitter norepinephrine. In this review, we cover what is known and not yet known about sensory nerve activities in adipose, focusing on their effector neuropeptide actions in the tissue.
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Affiliation(s)
- Gargi Mishra
- Department of Neurological Surgery, College of Medicine, The Ohio State University, Columbus, OH, USA
| | - Kristy L Townsend
- Department of Neurological Surgery, College of Medicine, The Ohio State University, Columbus, OH, USA.
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Lorsignol A, Rabiller L, Labit E, Casteilla L, Pénicaud L. The nervous system and adipose tissues: a tale of dialogues. Am J Physiol Endocrinol Metab 2023; 325:E480-E490. [PMID: 37729026 DOI: 10.1152/ajpendo.00115.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 08/16/2023] [Accepted: 09/18/2023] [Indexed: 09/22/2023]
Abstract
White, beige, and brown adipose tissues play a crucial role in maintaining energy homeostasis. Due to the heterogeneous and diffuse nature of fat pads, this balance requires a fine and coordinated control of many actors and therefore permanent dialogues between these tissues and the central nervous system. For about two decades, many studies have been devoted to describe the neuro-anatomical and functional complexity involved to ensure this dialogue. Thus, if it is now clearly demonstrated that there is an efferent sympathetic innervation of different fat depots controlling plasticity as well as metabolic functions of the fat pad, the crucial role of sensory innervation capable of detecting local signals informing the central nervous system of the metabolic state of the relevant pads is much more recent. The purpose of this review is to provide the current state of knowledge on this subject.
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Affiliation(s)
- Anne Lorsignol
- RESTORE, CNRS, Inserm, Université de Toulouse, Toulouse, France
| | - Lise Rabiller
- RESTORE, CNRS, Inserm, Université de Toulouse, Toulouse, France
| | - Elodie Labit
- RESTORE, CNRS, Inserm, Université de Toulouse, Toulouse, France
| | - Louis Casteilla
- RESTORE, CNRS, Inserm, Université de Toulouse, Toulouse, France
| | - Luc Pénicaud
- RESTORE, CNRS, Inserm, Université de Toulouse, Toulouse, France
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Mishra G, Townsend KL. The metabolic and functional roles of sensory nerves in adipose tissues. Nat Metab 2023; 5:1461-1474. [PMID: 37709960 DOI: 10.1038/s42255-023-00868-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 07/18/2023] [Indexed: 09/16/2023]
Abstract
Homeostatic regulation of adipose tissue is critical for the maintenance of energy balance and whole-body metabolism. The peripheral nervous system provides bidirectional neural communication between the brain and adipose tissue, thereby providing homeostatic control. Most research on adipose innervation and nerve functions has been limited to the sympathetic nerves and their neurotransmitter norepinephrine. In recent years, more work has focused on adipose sensory nerves, but the contributions of subsets of sensory nerves to metabolism and the specific roles contributed by sensory neuropeptides are still understudied. Advances in imaging of adipose innervation and newer tissue denervation techniques have confirmed that sensory nerves contribute to the regulation of adipose functions, including lipolysis and browning. Here, we summarize the historical and latest findings on the regulation, function and plasticity of adipose tissue sensory nerves that contribute to metabolically important processes such as lipolysis, vascular control and sympathetic axis cross-talk.
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Affiliation(s)
- Gargi Mishra
- Department of Neurological Surgery, College of Medicine, The Ohio State University, Columbus, OH, USA
| | - Kristy L Townsend
- Department of Neurological Surgery, College of Medicine, The Ohio State University, Columbus, OH, USA.
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8
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Wang Y, Ye L. Somatosensory innervation of adipose tissues. Physiol Behav 2023; 265:114174. [PMID: 36965573 PMCID: PMC11537203 DOI: 10.1016/j.physbeh.2023.114174] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 03/21/2023] [Accepted: 03/22/2023] [Indexed: 03/27/2023]
Abstract
The increasing prevalence of obesity and type 2 diabetes has led to a greater interest in adipose tissue physiology. Adipose tissue is now understood as an organ with endocrine and thermogenic capacities in addition to its role in fat storage. It plays a critical role in systemic metabolism and energy regulation, and its activity is tightly regulated by the nervous system. Fat is now recognized to receive sympathetic innervation, which transmits information from the brain, as well as sensory innervation, which sends information into the brain. The role of sympathetic innervation in adipose tissue has been extensively studied. However, the extent and the functional significance of sensory innervation have long been unclear. Recent studies have started to reveal that sensory neurons robustly innervate adipose tissue and play an important role in regulating fat activity. This brief review will discuss both historical evidence and recent advances, as well as important remaining questions about the sensory innervation of adipose tissue.
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Affiliation(s)
- Yu Wang
- Department of Neuroscience and Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Li Ye
- Department of Neuroscience and Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA; Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA.
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McMillan DW, Bigford GE, Farkas GJ. The Physiology of Neurogenic Obesity: Lessons from Spinal Cord Injury Research. Obes Facts 2023; 16:313-325. [PMID: 37231872 PMCID: PMC10427964 DOI: 10.1159/000530888] [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: 08/28/2022] [Accepted: 04/25/2023] [Indexed: 05/27/2023] Open
Abstract
BACKGROUND A spinal cord injury (SCI) from trauma or disease impairs sensorimotor pathways in somatic and autonomic divisions of the nervous system, affecting multiple body systems. Improved medical practices have increased survivability and life expectancy after SCI, allowing for the development of extensive metabolic comorbidities and profound changes in body composition that culminate in prevalent obesity. SUMMARY Obesity is the most common cardiometabolic component risk in people living with SCI, with a diagnostic body mass index cutoff of 22 kg/m2 to account for a phenotype of high adiposity and low lean mass. The metameric organization of specific divisions of the nervous system results in level-dependent pathology, with resulting sympathetic decentralization altering physiological functions such as lipolysis, hepatic lipoprotein metabolism, dietary fat absorption, and neuroendocrine signaling. In this manner, SCI provides a unique opportunity to study in vivo the "neurogenic" components of certain pathologies that otherwise are not readily observable in other populations. We discuss the unique physiology of neurogenic obesity after SCI, including the altered functions mentioned above as well as structural changes such as reduced skeletal muscle and bone mass and increased lipid deposition in the adipose tissue, skeletal muscle, bone marrow, and liver. KEY MESSAGE The study of neurogenic obesity after SCI gives us a unique neurological perspective on the physiology of obesity. The lessons learned from this field can guide future research and advancements to inform the study of obesity in persons with and without SCI.
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Affiliation(s)
- David W. McMillan
- Christine E. Lynn Rehabilitation Center for The Miami Project to Cure Paralysis at UHealth/Jackson Memorial, Miami, FL, USA
- Department of Neurological Surgery, University of Miami Leonard M. Miller School of Medicine, Miami, FL, USA
| | - Gregory E. Bigford
- Christine E. Lynn Rehabilitation Center for The Miami Project to Cure Paralysis at UHealth/Jackson Memorial, Miami, FL, USA
- Department of Neurological Surgery, University of Miami Leonard M. Miller School of Medicine, Miami, FL, USA
| | - Gary J. Farkas
- Christine E. Lynn Rehabilitation Center for The Miami Project to Cure Paralysis at UHealth/Jackson Memorial, Miami, FL, USA
- Department of Physical Medicine and Rehabilitation, University of Miami Leonard M. Miller School of Medicine, Miami, FL, USA
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Xue S, Lee D, Berry DC. Thermogenic adipose tissue in energy regulation and metabolic health. Front Endocrinol (Lausanne) 2023; 14:1150059. [PMID: 37020585 PMCID: PMC10067564 DOI: 10.3389/fendo.2023.1150059] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 03/07/2023] [Indexed: 04/07/2023] Open
Abstract
The ability to generate thermogenic fat could be a targeted therapy to thwart obesity and improve metabolic health. Brown and beige adipocytes are two types of thermogenic fat cells that regulate energy balance. Both adipocytes share common morphological, biochemical, and thermogenic properties. Yet, recent evidence suggests unique features exist between brown and beige adipocytes, such as their cellular origin and thermogenic regulatory processes. Beige adipocytes also appear highly plastic, responding to environmental stimuli and interconverting between beige and white adipocyte states. Additionally, beige adipocytes appear to be metabolically heterogenic and have substrate specificity. Nevertheless, obese and aged individuals cannot develop beige adipocytes in response to thermogenic fat-inducers, creating a key clinical hurdle to their therapeutic promise. Thus, elucidating the underlying developmental, molecular, and functional mechanisms that govern thermogenic fat cells will improve our understanding of systemic energy regulation and strive for new targeted therapies to generate thermogenic fat. This review will examine the recent advances in thermogenic fat biogenesis, molecular regulation, and the potential mechanisms for their failure.
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Affiliation(s)
| | | | - Daniel C. Berry
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, United States
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11
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Abstract
Brown adipose tissue (BAT) displays the unique capacity to generate heat through uncoupled oxidative phosphorylation that makes it a very attractive therapeutic target for cardiometabolic diseases. Here, we review BAT cellular metabolism, its regulation by the central nervous and endocrine systems and circulating metabolites, the plausible roles of this tissue in human thermoregulation, energy balance, and cardiometabolic disorders, and the current knowledge on its pharmacological stimulation in humans. The current definition and measurement of BAT in human studies relies almost exclusively on BAT glucose uptake from positron emission tomography with 18F-fluorodeoxiglucose, which can be dissociated from BAT thermogenic activity, as for example in insulin-resistant states. The most important energy substrate for BAT thermogenesis is its intracellular fatty acid content mobilized from sympathetic stimulation of intracellular triglyceride lipolysis. This lipolytic BAT response is intertwined with that of white adipose (WAT) and other metabolic tissues, and cannot be independently stimulated with the drugs tested thus far. BAT is an interesting and biologically plausible target that has yet to be fully and selectively activated to increase the body's thermogenic response and shift energy balance. The field of human BAT research is in need of methods able to directly, specifically, and reliably measure BAT thermogenic capacity while also tracking the related thermogenic responses in WAT and other tissues. Until this is achieved, uncertainty will remain about the role played by this fascinating tissue in human cardiometabolic diseases.
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Affiliation(s)
- André C Carpentier
- Division of Endocrinology, Department of Medicine, Centre de recherche du Centre hospitalier universitaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Quebec, J1H 5N4, Canada
| | - Denis P Blondin
- Division of Neurology, Department of Medicine, Centre de recherche du Centre hospitalier universitaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Quebec, J1H 5N4, Canada
| | | | - Denis Richard
- Centre de recherche de l’Institut universitaire de cardiologie et de pneumologie de Québec, Université Laval, Quebec City, Quebec, G1V 4G5, Canada
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12
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Lv X, Gao F, Cao X. Skeletal interoception in bone homeostasis and pain. Cell Metab 2022; 34:1914-1931. [PMID: 36257317 PMCID: PMC9742337 DOI: 10.1016/j.cmet.2022.09.025] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 09/07/2022] [Accepted: 09/26/2022] [Indexed: 01/24/2023]
Abstract
Accumulating evidence indicates that interoception maintains proper physiological status and orchestrates metabolic homeostasis by regulating feeding behaviors, glucose balance, and lipid metabolism. Continuous skeletal remodeling consumes a tremendous amount of energy to provide skeletal scaffolding, support muscle movement, store vital minerals, and maintain a niche for hematopoiesis, which are processes that also contribute to overall metabolic balance. Although skeletal innervation has been described for centuries, recent work has shown that skeletal metabolism is tightly regulated by the nervous system and that skeletal interoception regulates bone homeostasis. Here, we provide a general discussion of interoception and its effects on the skeleton and whole-body metabolism. We also discuss skeletal interoception-mediated regulation in the context of pathological conditions and skeletal pain as well as future challenges to our understanding of these process and how they can be leveraged for more effective therapy.
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Affiliation(s)
- Xiao Lv
- Center for Musculoskeletal Research, Department of Orthopaedic Surgery and Department of Biomedical Engineering, The Johns Hopkins University, Baltimore, MD 21205, USA
| | - Feng Gao
- Center for Musculoskeletal Research, Department of Orthopaedic Surgery and Department of Biomedical Engineering, The Johns Hopkins University, Baltimore, MD 21205, USA
| | - Xu Cao
- Center for Musculoskeletal Research, Department of Orthopaedic Surgery and Department of Biomedical Engineering, The Johns Hopkins University, Baltimore, MD 21205, USA.
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13
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Cardiac Sympathetic Denervation for the Management of Ventricular Arrhythmias. J Interv Card Electrophysiol 2022; 65:813-826. [PMID: 35397706 DOI: 10.1007/s10840-022-01211-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 03/29/2022] [Indexed: 01/01/2023]
Abstract
BACKGROUND The autonomic nervous system contributes to the pathogenesis of ventricular arrhythmias (VA). Though anti-arrhythmic drug therapy and catheter ablation are the mainstay of management of VAs, success may be limited in patients with more refractory arrhythmias. Sympathetic modulation is increasingly recognized as a valuable adjunct tool for managing VAs in patients with structural heart disease and inherited arrhythmias. RESULTS In this review, we explore the role of the sympathetic nervous system and rationale for cardiac sympathetic denervation (CSD) in VAs and provide a disease-focused review of the utility of CSD for patients both with and without structural heart disease. CONCLUSIONS We conclude that CSD is a reasonable therapeutic option for patients with VA, both with and without structural heart disease. Though not curative, many studies have demonstrated a significant reduction in the burden of VAs for the majority of patients undergoing the procedure. However, in patients with unilateral CSD and subsequent VA recurrence, complete bilateral CSD may provide long-lasting reprieve from VA.
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14
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Wang Y, Leung VH, Zhang Y, Nudell VS, Loud M, Servin-Vences MR, Yang D, Wang K, Moya-Garzon MD, Li VL, Long JZ, Patapoutian A, Ye L. The role of somatosensory innervation of adipose tissues. Nature 2022; 609:569-574. [PMID: 36045288 PMCID: PMC9477745 DOI: 10.1038/s41586-022-05137-7] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 07/22/2022] [Indexed: 12/28/2022]
Abstract
Adipose tissues communicate with the central nervous system to maintain whole-body energy homeostasis. The mainstream view is that circulating hormones secreted by the fat convey the metabolic state to the brain, which integrates peripheral information and regulates adipocyte function through noradrenergic sympathetic output1. Moreover, somatosensory neurons of the dorsal root ganglia innervate adipose tissue2. However, the lack of genetic tools to selectively target these neurons has limited understanding of their physiological importance. Here we developed viral, genetic and imaging strategies to manipulate sensory nerves in an organ-specific manner in mice. This enabled us to visualize the entire axonal projection of dorsal root ganglia from the soma to subcutaneous adipocytes, establishing the anatomical underpinnings of adipose sensory innervation. Functionally, selective sensory ablation in adipose tissue enhanced the lipogenic and thermogenetic transcriptional programs, resulting in an enlarged fat pad, enrichment of beige adipocytes and elevated body temperature under thermoneutral conditions. The sensory-ablation-induced phenotypes required intact sympathetic function. We postulate that beige-fat-innervating sensory neurons modulate adipocyte function by acting as a brake on the sympathetic system. These results reveal an important role of the innervation by dorsal root ganglia of adipose tissues, and could enable future studies to examine the role of sensory innervation of disparate interoceptive systems.
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Affiliation(s)
- Yu Wang
- grid.214007.00000000122199231Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, San Diego, CA USA ,grid.413575.10000 0001 2167 1581Howard Hughes Medical Institute, Chevy Chase, MD USA
| | - Verina H. Leung
- grid.214007.00000000122199231Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, San Diego, CA USA
| | - Yunxiao Zhang
- grid.214007.00000000122199231Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, San Diego, CA USA ,grid.413575.10000 0001 2167 1581Howard Hughes Medical Institute, Chevy Chase, MD USA
| | - Victoria S. Nudell
- grid.214007.00000000122199231Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, San Diego, CA USA
| | - Meaghan Loud
- grid.214007.00000000122199231Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, San Diego, CA USA ,grid.413575.10000 0001 2167 1581Howard Hughes Medical Institute, Chevy Chase, MD USA
| | - M. Rocio Servin-Vences
- grid.214007.00000000122199231Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, San Diego, CA USA ,grid.413575.10000 0001 2167 1581Howard Hughes Medical Institute, Chevy Chase, MD USA
| | - Dong Yang
- grid.214007.00000000122199231Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, San Diego, CA USA
| | - Kristina Wang
- grid.214007.00000000122199231Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, San Diego, CA USA
| | - Maria Dolores Moya-Garzon
- grid.168010.e0000000419368956Department of Pathology, Stanford School of Medicine, Sarafan ChEM-H, Stanford University, Stanford, CA USA
| | - Veronica L. Li
- grid.168010.e0000000419368956Department of Pathology, Stanford School of Medicine, Sarafan ChEM-H, Stanford University, Stanford, CA USA
| | - Jonathan Z. Long
- grid.168010.e0000000419368956Department of Pathology, Stanford School of Medicine, Sarafan ChEM-H, Stanford University, Stanford, CA USA
| | - Ardem Patapoutian
- Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, San Diego, CA, USA. .,Howard Hughes Medical Institute, Chevy Chase, MD, USA.
| | - Li Ye
- Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, San Diego, CA, USA.
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15
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Huesing C, Zhang R, Gummadi S, Lee N, Qualls-Creekmore E, Yu S, Morrison CD, Burk D, Berthoud HR, Neuhuber W, Münzberg H. Organization of sympathetic innervation of interscapular brown adipose tissue in the mouse. J Comp Neurol 2021; 530:1363-1378. [PMID: 34837221 DOI: 10.1002/cne.25281] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 11/01/2021] [Accepted: 11/15/2021] [Indexed: 12/24/2022]
Abstract
The interscapular brown adipose tissue (iBAT) is under sympathetic control, and recent studies emphasized the importance of efferent sympathetic and afferent sensory or humoral feedback systems to regulate adipose tissue function and overall metabolic health. However, functional studies of the sympathetic nervous system in the mouse are limited, because details of anatomy and fine structure are lacking. Here, we used reporter mice for tyrosine hydroxylase expressing neurons (TH:tomato mice), iDISCO tissue clearance, confocal, lightsheet, and electron microscopy to clarify that (a) iBAT receives sympathetic input via dorsal rami (instead of often cited intercostal nerves); (b) dorsal rami T1-T5 correspond to the postganglionic input from sympathetic chain ganglia (stellate/T1-T5); (c) dorsal rami serve as conduits for sympathetic axons that branch off in finer nerve bundles to enter iBAT; (d) axonal varicosities show strong differential innervation of brown (dense innervation) versus white (sparse innervation) adipocytes, that surround the core iBAT in the mouse and are intermingled in human adipose tissues, (e) axonal varicosities can form neuro-adipocyte junctions with brown adipocytes. Taken together, we demonstrate that sympathetic iBAT innervation is organized by specific nerves and terminal structures that can be surgically and genetically accessed for neuromodulatory purposes.
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Affiliation(s)
- Clara Huesing
- Neurobiology of Nutrition & Metabolism Department, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA
| | - Rui Zhang
- Neurobiology of Nutrition & Metabolism Department, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA
| | - Sanjeev Gummadi
- Neurobiology of Nutrition & Metabolism Department, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA
| | - Nathan Lee
- Neurobiology of Nutrition & Metabolism Department, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA
| | - Emily Qualls-Creekmore
- Neurobiology of Nutrition & Metabolism Department, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA
| | - Sangho Yu
- Neurobiology of Nutrition & Metabolism Department, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA
| | - Christopher D Morrison
- Neurobiology of Nutrition & Metabolism Department, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA
| | - David Burk
- Neurobiology of Nutrition & Metabolism Department, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA
| | - Hans Rudolf Berthoud
- Neurobiology of Nutrition & Metabolism Department, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA
| | - Winfried Neuhuber
- Institute of Anatomy and Cell Biology, Friedrich-Alexander-University of Erlangen-Nürnberg, Bavaria, Germany
| | - Heike Münzberg
- Neurobiology of Nutrition & Metabolism Department, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA
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16
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Fatty Acids Rescue the Thermogenic Function of Sympathetically Denervated Brown Fat. Biomolecules 2021; 11:biom11101428. [PMID: 34680061 PMCID: PMC8533276 DOI: 10.3390/biom11101428] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 09/22/2021] [Accepted: 09/25/2021] [Indexed: 02/04/2023] Open
Abstract
Sympathetic nervous system (SNS) innervation into brown adipose tissue (BAT) has been viewed as an impetus for brown fat thermogenesis. However, we surprisingly discovered that BAT SNS innervation is dispensable for mice to maintain proper body temperature during a prolonged cold exposure. Here we aimed to uncover the physiological factors compensating for maintaining brown fat thermogenesis in the absence of BAT innervation. After an initial decline of body temperature during cold exposure, mice with SNS surgical denervation in interscapular BAT gradually recovered their temperature comparable to that of sham-operated mice. The surgically denervated BAT also maintained a sizable uncoupling protein 1 (UCP1) protein along with basal norepinephrine (NE) at a similar level to that of sham controls, which were associated with increased circulating NE. Furthermore, the denervated mice exhibited increased free fatty acid levels in circulation. Indeed, surgical denervation of mice with CGI-58 deletion in adipocytes, a model lacking lipolytic capacity to release fatty acids from WAT, dramatically reduced BAT UCP1 protein and rendered the mice susceptible to cold. We conclude that circulating fatty acids and NE may serve as key factors for maintaining BAT thermogenic function and body temperature in the absence of BAT sympathetic innervation.
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17
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Garcia ML, Milanez MIO, Nishi EE, Sato AYS, Carvalho PM, Nogueira FN, Campos RR, Oyama LM, Bergamaschi CT. Retroperitoneal adipose tissue denervation improves cardiometabolic and autonomic dysfunction in a high fat diet model. Life Sci 2021; 283:119841. [PMID: 34298036 DOI: 10.1016/j.lfs.2021.119841] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/12/2021] [Accepted: 07/13/2021] [Indexed: 11/29/2022]
Abstract
Sympathetic vasomotor overactivity is a major feature leading to the cardiovascular dysfunction related to obesity. Considering that the retroperitoneal white adipose tissue (rWAT) is an important fat visceral depot and receives intense sympathetic and afferent innervations, the present study aimed to evaluate the effects evoked by bilateral rWAT denervation in obese rats. Male Wistar rats were fed with HFD for 8 consecutive weeks and rWAT denervation was performed at the 6th week. Arterial pressure, splanchnic and renal sympathetic vasomotor nerve activities were assessed and inflammation and the components of the renin -angiotensin system were evaluated in different white adipose tissue depots. HFD animals presented higher serum levels of leptin and glucose, an increase in arterial pressure and splanchnic sympathetic nerve activity; rWAT denervation, normalized these parameters. Pro-inflammatory cytokines levels were significantly increased, as well as RAAS gene expression in WAT of HFD animals; rWAT denervation significantly attenuated these changes. In conclusion, HFD promotes vasomotor sympathetic overactivation and inflammation with repercussions on the cardiovascular system. In conclusion, the neural communication between WAT and the brain is fundamental to trigger sympathetic vasomotor activation and this pathway is a possible new therapeutic target to treat obesity-associated cardiovascular dysfunction.
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Affiliation(s)
- Michelle L Garcia
- Department of Physiology, Escola Paulista de Medicina, Universidade Federal de São Paulo, Brazil
| | - Maycon I O Milanez
- Department of Physiology, Escola Paulista de Medicina, Universidade Federal de São Paulo, Brazil
| | - Erika E Nishi
- Department of Physiology, Escola Paulista de Medicina, Universidade Federal de São Paulo, Brazil
| | - Alex Y S Sato
- Department of Physiology, Escola Paulista de Medicina, Universidade Federal de São Paulo, Brazil
| | - Polliane M Carvalho
- Department of Biomaterials and Oral Biology, Faculdade de Odontologia, Universidade de São Paulo, Brazil
| | - Fernando N Nogueira
- Department of Biomaterials and Oral Biology, Faculdade de Odontologia, Universidade de São Paulo, Brazil
| | - Ruy R Campos
- Department of Physiology, Escola Paulista de Medicina, Universidade Federal de São Paulo, Brazil
| | - Lila M Oyama
- Department of Physiology, Escola Paulista de Medicina, Universidade Federal de São Paulo, Brazil
| | - Cássia T Bergamaschi
- Department of Physiology, Escola Paulista de Medicina, Universidade Federal de São Paulo, Brazil.
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18
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Lin EE, Scott-Solomon E, Kuruvilla R. Peripheral Innervation in the Regulation of Glucose Homeostasis. Trends Neurosci 2020; 44:189-202. [PMID: 33229051 DOI: 10.1016/j.tins.2020.10.015] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 10/07/2020] [Accepted: 10/27/2020] [Indexed: 02/07/2023]
Abstract
Precise regulation of circulating glucose is crucial for human health and ensures a sufficient supply to the brain, which relies almost exclusively on glucose for metabolic energy. Glucose homeostasis is coordinated by hormone-secreting endocrine cells in the pancreas, as well as glucose utilization and production in peripheral metabolic tissues including the liver, muscle, and adipose tissue. Glucose-regulatory tissues receive dense innervation from sympathetic, parasympathetic, and sensory fibers. In this review, we summarize the functions of peripheral nerves in glucose regulation and metabolism. Dynamic changes in peripheral innervation have also been observed in animal models of obesity and diabetes. Together, these studies highlight the importance of peripheral nerves as a new therapeutic target for metabolic disorders.
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Affiliation(s)
- Eugene E Lin
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | | | - Rejji Kuruvilla
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA.
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19
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Eichwald T, Talbot S. Neuro-Immunity Controls Obesity-Induced Pain. Front Hum Neurosci 2020; 14:181. [PMID: 32581740 PMCID: PMC7295985 DOI: 10.3389/fnhum.2020.00181] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 04/23/2020] [Indexed: 12/16/2022] Open
Abstract
The prevalence of obesity skyrocketed over the past decades to become a significant public health problem. Obesity is recognized as a low-grade inflammatory disease and is linked with several comorbidities such as diabetes, circulatory disease, common neurodegenerative diseases, as well as chronic pain. Adipocytes are a major neuroendocrine organ that continually, and systemically, releases pro-inflammatory factors. While the exact mechanisms driving obesity-induced pain remain poorly defined, nociceptor hypersensitivity may result from the systemic state of inflammation characteristic of obesity as well as weight surplus-induced mechanical stress. Obesity and pain also share various genetic mutations, lifestyle risk factors, and metabolic pathways. For instance, fat pads are often found hyper-innervated and rich in immune cell types of multiple origins. These immunocytes release cytokines, amplifying nociceptor function, which, in turn, via locally released neuropeptides, sustain immunocytes' function. Here, we posit that along with mechanical stress stemming from extra weight, the local neuro-immune interplay occurring within the fat pads maintains the state of chronic low-grade inflammation and heightens sensory hypersensitivity. Overall, stopping such harmful neuro-immune crosstalk may constitute a novel pathway to prevent obesity-associated comorbidities, including neuronal hypersensitivity.
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Affiliation(s)
- Tuany Eichwald
- Département de Pharmacologie et Physiologie, Faculté de Médecine, Université de Montréal, Montreal, QC, Canada
- Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Sebastien Talbot
- Département de Pharmacologie et Physiologie, Faculté de Médecine, Université de Montréal, Montreal, QC, Canada
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20
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Dalmasso C, Leachman JR, Osborn JL, Loria AS. Sensory signals mediating high blood pressure via sympathetic activation: role of adipose afferent reflex. Am J Physiol Regul Integr Comp Physiol 2019; 318:R379-R389. [PMID: 31868518 DOI: 10.1152/ajpregu.00079.2019] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Blood pressure regulation in health and disease involves a balance between afferent and efferent signals from multiple organs and tissues. Although there are numerous reviews focused on the role of sympathetic nerves in different models of hypertension, few have revised the contribution of afferent nerves innervating adipose tissue and their role in the development of obesity-induced hypertension. Both clinical and basic research support the beneficial effects of bilateral renal denervation in lowering blood pressure. However, recent studies revealed that afferent signals from adipose tissue, in an adipose-brain-peripheral pathway, could contribute to the increased sympathetic activation and blood pressure during obesity. This review focuses on the role of adipose tissue afferent reflexes and briefly describes a number of other afferent reflexes modulating blood pressure. A comprehensive understanding of how multiple afferent reflexes contribute to the pathophysiology of essential and/or obesity-induced hypertension may provide significant insights into improving antihypertensive therapeutic approaches.
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Affiliation(s)
- Carolina Dalmasso
- Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, Kentucky
| | - Jacqueline R Leachman
- Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, Kentucky
| | - Jeffrey L Osborn
- Department of Biology, College of Arts and Sciences, University of Kentucky, Lexington, Kentucky
| | - Analia S Loria
- Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, Kentucky
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21
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Jung SM, Sanchez-Gurmaches J, Guertin DA. Brown Adipose Tissue Development and Metabolism. Handb Exp Pharmacol 2019; 251:3-36. [PMID: 30203328 DOI: 10.1007/164_2018_168] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Brown adipose tissue is well known to be a thermoregulatory organ particularly important in small rodents and human infants, but it was only recently that its existence and significance to metabolic fitness in adult humans have been widely realized. The ability of active brown fat to expend high amounts of energy has raised interest in stimulating thermogenesis therapeutically to treat metabolic diseases related to obesity and type 2 diabetes. In parallel, there has been a surge of research aimed at understanding the biology of rodent and human brown fat development, its remarkable metabolic properties, and the phenomenon of white fat browning, in which white adipocytes can be converted into brown like adipocytes with similar thermogenic properties. Here, we review the current understanding of the developmental and metabolic pathways involved in forming thermogenic adipocytes, and highlight some of the many unknown functions of brown fat that make its study a rich and exciting area for future research.
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Affiliation(s)
- Su Myung Jung
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Joan Sanchez-Gurmaches
- Division of Endocrinology, Division of Developmental Biology, Cincinnati Children's Hospital Research Foundation, Cincinnati, OH, USA. .,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA.
| | - David A Guertin
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA. .,Molecular, Cell and Cancer Biology Program, University of Massachusetts Medical School, Worcester, MA, USA. .,Lei Weibo Institute for Rare Diseases, University of Massachusetts Medical School, Worcester, MA, USA.
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22
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Liu BX, Qiu M, Zong PY, Chen XG, Zhao K, Li Y, Li P, Sun W, Kong XQ. Distribution, Morphological Characterization, and Resiniferatoxin-Susceptibility of Sensory Neurons That Innervate Rat Perirenal Adipose Tissue. Front Neuroanat 2019; 13:29. [PMID: 30930754 PMCID: PMC6427091 DOI: 10.3389/fnana.2019.00029] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 02/19/2019] [Indexed: 12/28/2022] Open
Abstract
Perirenal adipose tissue (PrAT) is a visceral adipose tissue involved in the pathogenesis of obesity and cardiovascular diseases via neural pathways. However, the origins, morphological characterization, and resiniferatoxin (RTX)-susceptibility of sensory neurons that innervate rat PrAT are yet unclear. Using neural tracing, an injection of DiI (1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate) into PrAT revealed that sensory neurons that innervate PrAT reside in T9-L3 dorsal root ganglia (DRG). Peak labeling occurred in T13 and L1 DRGs. Two distinct peaks were observed in cross-sectional areas of the labeled soma, and the mean cross-sectional area was 717.1 ± 27.7 μm2. Immunofluorescence staining for transient receptor potential cation channel subfamily V member 1 (TRPV1) separated DiI-positive neurons into three subpopulations: small TRPV1-negative, small TRPV1-positive, and large TRPV1-negative. Furthermore, the injection of RTX into PrAT reduced labeled cells by 36.7% where TRPV1-positive cells were the main target of RTX denervation. These novel findings provide a structural basis for future TRPV1-dependent and TRPV1-independent studies on the sensory innervation of PrAT, which may be of interest for future therapeutic obesity treatment and intervention.
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Affiliation(s)
- Bo-Xun Liu
- Department of Cardiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Ming Qiu
- Department of Cardiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Peng-Yu Zong
- Department of Cardiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Xu-Guan Chen
- Department of Cardiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Kun Zhao
- Department of Cardiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Yong Li
- Department of Cardiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Peng Li
- Department of Cardiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Wei Sun
- Department of Cardiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Xiang-Qing Kong
- Department of Cardiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
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23
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Guilherme A, Henriques F, Bedard AH, Czech MP. Molecular pathways linking adipose innervation to insulin action in obesity and diabetes mellitus. Nat Rev Endocrinol 2019; 15:207-225. [PMID: 30733616 PMCID: PMC7073451 DOI: 10.1038/s41574-019-0165-y] [Citation(s) in RCA: 109] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Adipose tissue comprises adipocytes and many other cell types that engage in dynamic crosstalk in a highly innervated and vascularized tissue matrix. Although adipose tissue has been studied for decades, it has been appreciated only in the past 5 years that extensive arborization of nerve fibres has a dominant role in regulating the function of adipose tissue. This Review summarizes the latest literature, which suggests that adipocytes signal to local sensory nerve fibres in response to perturbations in lipolysis and lipogenesis. Such adipocyte signalling to the central nervous system causes sympathetic output to distant adipose depots and potentially other metabolic tissues to regulate systemic glucose homeostasis. Paracrine factors identified in the past few years that mediate such adipocyte-neuron crosstalk are also reviewed. Similarly, immune cells and endothelial cells within adipose tissue communicate with local nerve fibres to modulate neurotransmitter tone, blood flow, adipocyte differentiation and energy expenditure, including adipose browning to produce heat. This understudied field of neurometabolism related to adipose tissue biology has great potential to reveal new mechanistic insights and potential therapeutic strategies for obesity and type 2 diabetes mellitus.
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Affiliation(s)
- Adilson Guilherme
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Felipe Henriques
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Alexander H Bedard
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Michael P Czech
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA.
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24
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Cao Q, Jing J, Cui X, Shi H, Xue B. Sympathetic nerve innervation is required for beigeing in white fat. Physiol Rep 2019; 7:e14031. [PMID: 30873754 PMCID: PMC6418318 DOI: 10.14814/phy2.14031] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 02/28/2019] [Accepted: 03/01/2019] [Indexed: 11/24/2022] Open
Abstract
It is increasingly recognized that activation of beige adipocyte thermogenesis by pharmacological or genetic approaches increases energy expenditure and alleviates obesity. Sympathetic nervous system (SNS) directly innervating brown adipose tissue (BAT) and white adipose tissue (WAT) plays a key role in promoting nonshivering thermogenesis. However, direct evidence that supports the importance of SNS innervation for beige adipocyte formation is still lacking, and the significance of beige adipocyte thermogenesis in protection of body temperature during cold challenge is not clear. Here we tested the necessity of SNS innervation into WAT for beige adipocyte formation in mice with defective brown fat thermogenesis via interscapular BAT (iBAT) SNS denervation. SNS denervation was achieved by microinjection of 6-hydroxydopamine (6-OHDA), a selective neurotoxin to SNS nerves, into iBAT, inguinal WAT (iWAT), or both. The partial chemical denervation of iBAT SNS down-regulated UCP-1 protein expression in iBAT demonstrated by immunoblotting and immunohistochemical measurements. This was associated with an up-regulation of UCP1 protein expression and enhanced formation of beige cells in iWAT of mice with iBAT SNS denervation. In contrast, the chemical denervation of iWAT SNS completely abolished the upregulated UCP-1 protein and beige cell formation in iWAT of mice with iBAT SNS denervation. Our data demonstrate that SNS innervation in WAT is required for beige cell formation during cold-induced thermogenesis. We conclude that there exists a coordinated thermoregulation for BAT and WAT thermogenesis via a functional cross talk between BAT and WAT SNS.
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Affiliation(s)
- Qiang Cao
- School of BiologyGeorgia State UniversityAtlantaGeorgia
| | - Jia Jing
- School of BiologyGeorgia State UniversityAtlantaGeorgia
| | - Xin Cui
- School of BiologyGeorgia State UniversityAtlantaGeorgia
| | - Hang Shi
- School of BiologyGeorgia State UniversityAtlantaGeorgia
| | - Bingzhong Xue
- School of BiologyGeorgia State UniversityAtlantaGeorgia
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25
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Srivastava S, Veech RL. Brown and Brite: The Fat Soldiers in the Anti-obesity Fight. Front Physiol 2019; 10:38. [PMID: 30761017 PMCID: PMC6363669 DOI: 10.3389/fphys.2019.00038] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 01/14/2019] [Indexed: 12/16/2022] Open
Abstract
Brown adipose tissue (BAT) is proposed to maintain thermal homeostasis through dissipation of chemical energy as heat by the uncoupling proteins (UCPs) present in their mitochondria. The recent demonstration of the presence of BAT in humans has invigorated research in this area. The research has provided many new insights into the biology and functioning of this tissue and the biological implications of its altered activities. Another finding of interest is browning of white adipose tissue (WAT) resulting in what is known as beige/brite cells, which have increased mitochondrial proteins and UCPs. In general, it has been observed that the activation of BAT is associated with various physiological improvements such as a reduction in blood glucose levels increased resting energy expenditure and reduced weight. Given the similar physiological functions of BAT and beige/ brite cells and the higher mass of WAT compared to BAT, it is likely that increasing the brite/beige cells in WATs may also lead to greater metabolic benefits. However, development of treatments targeting brown fat or WAT browning would require not only a substantial understanding of the biology of these tissues but also the effect of altering their activity levels on whole body metabolism and physiology. In this review, we present evidence from recent literature on the substrates utilized by BAT, regulation of BAT activity and browning by circulating molecules. We also present dietary and pharmacological activators of brown and beige/brite adipose tissue and the effect of physical exercise on BAT activity and browning.
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Affiliation(s)
- Shireesh Srivastava
- Systems Biology for Biofuels Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Richard L Veech
- Laboratory of Metabolic Control, National Institute on Alcohol Abuse and Alcoholism (NIAAA), National Institutes of Health (NIH), Bethesda, MD, United States
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26
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Guilherme A, Pedersen DJ, Henriques F, Bedard AH, Henchey E, Kelly M, Morgan DA, Rahmouni K, Czech MP. Neuronal modulation of brown adipose activity through perturbation of white adipocyte lipogenesis. Mol Metab 2018; 16:116-125. [PMID: 30005879 PMCID: PMC6157614 DOI: 10.1016/j.molmet.2018.06.014] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 06/13/2018] [Accepted: 06/25/2018] [Indexed: 01/14/2023] Open
Abstract
OBJECTIVE Crosstalk between adipocytes and local neurons may be an important regulatory mechanism to control energy homeostasis. We previously reported that perturbation of adipocyte de novo lipogenesis (DNL) by deletion of fatty acid synthase (FASN) expands sympathetic neurons within white adipose tissue (WAT) and stimulates the appearance of "beige" adipocytes. Here we tested whether WAT DNL activity can also influence neuronal regulation and thermogenesis in brown adipose tissue (BAT). METHODS AND RESULTS Induced deletion of FASN in all adipocytes in mature mice (iAdFASNKO) enhanced sympathetic innervation and neuronal activity as well as UCP1 expression in both WAT and BAT. This increased sympathetic innervation could be observed at both 22 °C and 30 °C, indicating it is not a response to heat loss but rather adipocyte signaling. In contrast, selective ablation of FASN in brown adipocytes of mice (iUCP1FASNKO) failed to modulate sympathetic innervation and the thermogenic program in BAT. Surprisingly, DNL in brown adipocytes was also dispensable in maintaining euthermia when UCP1FASNKO mice were cold-exposed. CONCLUSION These results indicate that DNL in white adipocytes influences long distance signaling to BAT, which can modify BAT sympathetic innervation and expression of genes involved in thermogenesis.
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Affiliation(s)
- Adilson Guilherme
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA
| | - David J Pedersen
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA
| | - Felipe Henriques
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA
| | - Alexander H Bedard
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA
| | - Elizabeth Henchey
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA
| | - Mark Kelly
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA
| | - Donald A Morgan
- Department of Pharmacology, University of Iowa Carver College of Medicine, Iowa City, IA, 52242, USA
| | - Kamal Rahmouni
- Department of Pharmacology, University of Iowa Carver College of Medicine, Iowa City, IA, 52242, USA
| | - Michael P Czech
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA.
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