1
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Hayashi R, Srisomboon Y, Iijima K, Maniak PJ, Tei R, Kobayashi T, Matsunaga M, Luo H, Masuda MY, O'Grady SM, Kita H. Cholinergic sensing of allergen exposure by airway epithelium promotes type 2 immunity in the lungs. J Allergy Clin Immunol 2024; 153:793-808.e2. [PMID: 38000698 PMCID: PMC10939907 DOI: 10.1016/j.jaci.2023.10.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 09/26/2023] [Accepted: 10/09/2023] [Indexed: 11/26/2023]
Abstract
BACKGROUND Nonneuronal cells, including epithelial cells, can produce acetylcholine (ACh). Muscarinic ACh receptor antagonists are used clinically to treat asthma and other medical conditions; however, knowledge regarding the roles of ACh in type 2 immunity is limited. OBJECTIVE Our aim was to investigate the roles of epithelial ACh in allergic immune responses. METHODS Human bronchial epithelial (HBE) cells were cultured with allergen extracts, and their ACh production and IL-33 secretion were studied in vitro. To investigate immune responses in vivo, naive BALB/c mice were treated intranasally with different muscarinic ACh receptor antagonists and then exposed intranasally to allergens. RESULTS At steady state, HBE cells expressed cellular components necessary for ACh production, including choline acetyltransferase and organic cation transporters. Exposure to allergens caused HBE cells to rapidly release ACh into the extracellular medium. Pharmacologic or small-interfering RNA-based blocking of ACh production or autocrine action through the M3 muscarinic ACh receptors in HBE cells suppressed allergen-induced ATP release, calcium mobilization, and extracellular secretion of IL-33. When naive mice were exposed to allergens, ACh was quickly released into the airway lumen. A series of clinical M3 muscarinic ACh receptor antagonists inhibited allergen-induced IL-33 secretion and innate type 2 immune response in the mouse airways. In a preclinical murine model of asthma, an ACh receptor antagonist suppressed allergen-induced airway inflammation and airway hyperreactivity. CONCLUSIONS ACh is released quickly by airway epithelial cells on allergen exposure, and it plays an important role in type 2 immunity. The epithelial ACh system can be considered a therapeutic target in allergic airway diseases.
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Affiliation(s)
- Ryusuke Hayashi
- Division of Allergy, Asthma and Clinical Immunology, Mayo Clinic, Scottsdale, Ariz; Department of Medicine, Mayo Clinic, Scottsdale, Ariz
| | - Yotesawee Srisomboon
- Department of Animal Science, University of Minnesota, St Paul, Minn; Department of Integrative Biology and Physiology, University of Minnesota, St Paul, Minn
| | - Koji Iijima
- Division of Allergy, Asthma and Clinical Immunology, Mayo Clinic, Scottsdale, Ariz; Department of Medicine, Mayo Clinic, Scottsdale, Ariz
| | - Peter J Maniak
- Department of Animal Science, University of Minnesota, St Paul, Minn; Department of Integrative Biology and Physiology, University of Minnesota, St Paul, Minn
| | - Rinna Tei
- Division of Allergy, Asthma and Clinical Immunology, Mayo Clinic, Scottsdale, Ariz; Department of Medicine, Mayo Clinic, Scottsdale, Ariz
| | - Takao Kobayashi
- Division of Allergy, Asthma and Clinical Immunology, Mayo Clinic, Scottsdale, Ariz; Department of Medicine, Mayo Clinic, Scottsdale, Ariz
| | - Mayumi Matsunaga
- Division of Allergy, Asthma and Clinical Immunology, Mayo Clinic, Scottsdale, Ariz; Department of Medicine, Mayo Clinic, Scottsdale, Ariz
| | - Huijun Luo
- Division of Allergy, Asthma and Clinical Immunology, Mayo Clinic, Scottsdale, Ariz; Department of Medicine, Mayo Clinic, Scottsdale, Ariz
| | - Mia Y Masuda
- Mayo Clinic Graduate School of Biomedical Sciences, Rochester, Minn; Mayo Clinic Graduate School of Biomedical Sciences, Scottsdale, Ariz
| | - Scott M O'Grady
- Department of Animal Science, University of Minnesota, St Paul, Minn; Department of Integrative Biology and Physiology, University of Minnesota, St Paul, Minn
| | - Hirohito Kita
- Division of Allergy, Asthma and Clinical Immunology, Mayo Clinic, Scottsdale, Ariz; Department of Medicine, Mayo Clinic, Scottsdale, Ariz; Department of Immunology, Mayo Clinic Rochester, Rochester, Minn; Department of Immunology, Mayo Clinic Arizona, Scottsdale, Ariz.
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2
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Doyle ME, Premathilake HU, Yao Q, Mazucanti CH, Egan JM. Physiology of the tongue with emphasis on taste transduction. Physiol Rev 2023; 103:1193-1246. [PMID: 36422992 PMCID: PMC9942923 DOI: 10.1152/physrev.00012.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The tongue is a complex multifunctional organ that interacts and senses both interoceptively and exteroceptively. Although it is easily visible to almost all of us, it is relatively understudied and what is in the literature is often contradictory or is not comprehensively reported. The tongue is both a motor and a sensory organ: motor in that it is required for speech and mastication, and sensory in that it receives information to be relayed to the central nervous system pertaining to the safety and quality of the contents of the oral cavity. Additionally, the tongue and its taste apparatus form part of an innate immune surveillance system. For example, loss or alteration in taste perception can be an early indication of infection as became evident during the present global SARS-CoV-2 pandemic. Here, we particularly emphasize the latest updates in the mechanisms of taste perception, taste bud formation and adult taste bud renewal, and the presence and effects of hormones on taste perception, review the understudied lingual immune system with specific reference to SARS-CoV-2, discuss nascent work on tongue microbiome, as well as address the effect of systemic disease on tongue structure and function, especially in relation to taste.
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Affiliation(s)
- Máire E Doyle
- Diabetes Section/Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, Maryland
| | - Hasitha U Premathilake
- Diabetes Section/Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, Maryland
| | - Qin Yao
- Diabetes Section/Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, Maryland
| | - Caio H Mazucanti
- Diabetes Section/Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, Maryland
| | - Josephine M Egan
- Diabetes Section/Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, Maryland
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3
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Li L, Ma M, Duan T, Sui X. The critical roles and therapeutic implications of tuft cells in cancer. Front Pharmacol 2022; 13:1047188. [PMID: 36569325 PMCID: PMC9780677 DOI: 10.3389/fphar.2022.1047188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Accepted: 11/21/2022] [Indexed: 12/13/2022] Open
Abstract
Tuft cells are solitary chemosensory epithelial cells with microvilli at the top, which are found in hollow organs such as the gastrointestinal tract, pancreas, and lungs. Recently, an increasing number of studies have revealed the chemotactic abilities and immune function of the tuft cells, and numerous efforts have been devoted to uncovering the role of tuft cells in tumors. Notably, accumulating evidence has shown that the specific genes (POU2F3, DCLK1) expressed in tuft cells are involved in vital processes related with carcinogenesis and cancer development. However, the interaction between the tuft cells and cancer remains to be further elucidated. Here, based on an introduction of biological functions and specific markers of the tuft cells, we have summarized the functional roles and potential therapeutic implications of tuft cells in cancers, including pancreatic cancer, lung cancer, gastric cancer, colon cancer, and liver cancer, which is in the hope of inspiring the future research in validating tuft cells as novel strategies for cancer therapies.
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Affiliation(s)
- Lin Li
- School of Pharmacy, Hangzhou Normal University, Hangzhou, China
| | - Mengmeng Ma
- School of Pharmacy, Hangzhou Normal University, Hangzhou, China
| | - Ting Duan
- School of Pharmacy, Hangzhou Normal University, Hangzhou, China,*Correspondence: Ting Duan, ; Xinbing Sui,
| | - Xinbing Sui
- School of Pharmacy, Hangzhou Normal University, Hangzhou, China,Department of Medical Oncology, The Affiliated Hospital of Hangzhou Normal University, Hangzhou Normal University, Hangzhou, China,*Correspondence: Ting Duan, ; Xinbing Sui,
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4
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Sweet Taste Signaling: The Core Pathways and Regulatory Mechanisms. Int J Mol Sci 2022; 23:ijms23158225. [PMID: 35897802 PMCID: PMC9329783 DOI: 10.3390/ijms23158225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 07/23/2022] [Accepted: 07/25/2022] [Indexed: 12/10/2022] Open
Abstract
Sweet taste, a proxy for sugar-derived calories, is an important driver of food intake, and animals have evolved robust molecular and cellular machinery for sweet taste signaling. The overconsumption of sugar-derived calories is a major driver of obesity and other metabolic diseases. A fine-grained appreciation of the dynamic regulation of sweet taste signaling mechanisms will be required for designing novel noncaloric sweeteners with better hedonic and metabolic profiles and improved consumer acceptance. Sweet taste receptor cells express at least two signaling pathways, one mediated by a heterodimeric G-protein coupled receptor encoded by taste 1 receptor members 2 and 3 (TAS1R2 + TAS1R3) genes and another by glucose transporters and the ATP-gated potassium (KATP) channel. Despite these important discoveries, we do not fully understand the mechanisms regulating sweet taste signaling. We will introduce the core components of the above sweet taste signaling pathways and the rationale for having multiple pathways for detecting sweet tastants. We will then highlight the roles of key regulators of the sweet taste signaling pathways, including downstream signal transduction pathway components expressed in sweet taste receptor cells and hormones and other signaling molecules such as leptin and endocannabinoids.
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5
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Cherkashin AP, Rogachevskaja OA, Kabanova NV, Kotova PD, Bystrova MF, Kolesnikov SS. Taste Cells of the Type III Employ CASR to Maintain Steady Serotonin Exocytosis at Variable Ca 2+ in the Extracellular Medium. Cells 2022; 11:cells11081369. [PMID: 35456048 PMCID: PMC9030112 DOI: 10.3390/cells11081369] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 04/07/2022] [Accepted: 04/11/2022] [Indexed: 12/17/2022] Open
Abstract
Type III taste cells are the only taste bud cells which express voltage-gated (VG) Ca2+ channels and employ Ca2+-dependent exocytosis to release neurotransmitters, particularly serotonin. The taste bud is a tightly packed cell population, wherein extracellular Ca2+ is expected to fluctuate markedly due to the electrical activity of taste cells. It is currently unclear whether the Ca2+ entry-driven synapse in type III cells could be reliable enough at unsteady extracellular Ca2. Here we assayed depolarization-induced Ca2+ signals and associated serotonin release in isolated type III cells at varied extracellular Ca2+. It turned out that the same depolarizing stimulus elicited invariant Ca2+ signals in type III cells irrespective of bath Ca2+ varied within 0.5–5 mM. The serotonin release from type III cells was assayed with the biosensor approach by using HEK-293 cells co-expressing the recombinant 5-HT4 receptor and genetically encoded cAMP sensor Pink Flamindo. Consistently with the weak Ca2+ dependence of intracellular Ca2+ transients produced by VG Ca2+ entry, depolarization-triggered serotonin secretion varied negligibly with bath Ca2+. The evidence implicated the extracellular Ca2+-sensing receptor in mediating the negative feedback mechanism that regulates VG Ca2+ entry and levels off serotonin release in type III cells at deviating Ca2+ in the extracellular medium.
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6
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Roper SD. Chemical and electrical synaptic interactions among taste bud cells. CURRENT OPINION IN PHYSIOLOGY 2021; 20:118-125. [PMID: 33521414 DOI: 10.1016/j.cophys.2020.12.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Chemical synapses between taste cells were first proposed based on electron microscopy of fish taste buds. Subsequently, researchers found considerable evidence for electrical coupling in fish, amphibian, and possibly mammalian taste buds. The development lingual slice and isolated cell preparations allowed detailed investigations of cell-cell interactions, both chemical and electrical, in taste buds. The identification of serotonin and ATP as taste neurotransmitters focused attention onto chemical synaptic interactions between taste cells and research on electrical coupling faded. Findings from Ca2+ imaging, electrophysiology, and molecular biology indicate that several neurotransmitters, including ATP, serotonin, GABA, acetylcholine, and norepinephrine, are secreted by taste cells and exert paracrine interactions in taste buds. Most work has been done on interactions between Type II and Type III taste cells. This brief review follows the trail of studies on cell-cell interactions in taste buds, from the initial ultrastructural observations to the most recent optogenetic manipulations.
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Affiliation(s)
- Stephen D Roper
- Department of Physiology & Biophysics and Department of Otolaryngology, Miller School of Medicine, University of Miami, FL 33136
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7
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Billipp TE, Nadjsombati MS, von Moltke J. Tuning tuft cells: new ligands and effector functions reveal tissue-specific function. Curr Opin Immunol 2020; 68:98-106. [PMID: 33166855 DOI: 10.1016/j.coi.2020.09.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 09/17/2020] [Accepted: 09/17/2020] [Indexed: 12/11/2022]
Abstract
Tuft cells are rare chemosensory epithelial cells that monitor their environment and relay messages to the surrounding tissue via secretion of neuromodulatory and immunomodulatory molecules. In the small intestine tuft cells detect helminth infection, protist colonization, and bacterial dysbiosis, and initiate a type 2 immune response characterized by tissue remodeling. In the airways, tuft cells sense bacteria, allergens, and noxious stimuli and drive evasive behavior, neuroinflammation, and anti-bacterial responses. Here we summarize the most recent tuft cell research and discuss how these findings have provided insight into tuft cell diversity. Built around a core program of chemosensing, tuft cell receptors and effector functions are tuned to the unique environmental exposure and physiology of their surrounding tissue.
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Affiliation(s)
- Tyler E Billipp
- Department of Immunology, University of Washington School of Medicine, Seattle, WA, 98109, USA
| | - Marija S Nadjsombati
- Department of Immunology, University of Washington School of Medicine, Seattle, WA, 98109, USA
| | - Jakob von Moltke
- Department of Immunology, University of Washington School of Medicine, Seattle, WA, 98109, USA.
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8
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Rohde K, Schamarek I, Blüher M. Consequences of Obesity on the Sense of Taste: Taste Buds as Treatment Targets? Diabetes Metab J 2020; 44:509-528. [PMID: 32431111 PMCID: PMC7453985 DOI: 10.4093/dmj.2020.0058] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 03/25/2020] [Indexed: 12/19/2022] Open
Abstract
Premature obesity-related mortality is caused by cardiovascular and pulmonary diseases, type 2 diabetes mellitus, physical disabilities, osteoarthritis, and certain types of cancer. Obesity is caused by a positive energy balance due to hyper-caloric nutrition, low physical activity, and energy expenditure. Overeating is partially driven by impaired homeostatic feedback of the peripheral energy status in obesity. However, food with its different qualities is a key driver for the reward driven hedonic feeding with tremendous consequences on calorie consumption. In addition to visual and olfactory cues, taste buds of the oral cavity process the earliest signals which affect the regulation of food intake, appetite and satiety. Therefore, taste buds may play a crucial role how food related signals are transmitted to the brain, particularly in priming the body for digestion during the cephalic phase. Indeed, obesity development is associated with a significant reduction in taste buds. Impaired taste bud sensitivity may play a causal role in the pathophysiology of obesity in children and adolescents. In addition, genetic variation in taste receptors has been linked to body weight regulation. This review discusses the importance of taste buds as contributing factors in the development of obesity and how obesity may affect the sense of taste, alterations in food preferences and eating behavior.
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Affiliation(s)
- Kerstin Rohde
- Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Center Munich at the University of Leipzig and University Hospital Leipzig, Leipzig, Germany.
| | - Imke Schamarek
- Medical Department III (Endocrinology, Nephrology and Rheumatology), University of Leipzig, Leipzig, Germany
| | - Matthias Blüher
- Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Center Munich at the University of Leipzig and University Hospital Leipzig, Leipzig, Germany.
- Medical Department III (Endocrinology, Nephrology and Rheumatology), University of Leipzig, Leipzig, Germany
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9
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Pan J, Zhang L, Shao X, Huang J. Acetylcholine From Tuft Cells: The Updated Insights Beyond Its Immune and Chemosensory Functions. Front Cell Dev Biol 2020; 8:606. [PMID: 32733896 PMCID: PMC7359717 DOI: 10.3389/fcell.2020.00606] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Accepted: 06/19/2020] [Indexed: 12/21/2022] Open
Abstract
Tuft cells, rare solitary chemosensory cells, are distributed in mucosal epithelium throughout mammalian organs. Their nomenclatures are various in different organs and may be confused with other similar cells. Current studies mainly focus on their chemosensory ability and immune functions in type 2 inflammation. Several state-of-the-art reviews have already systematically discussed their role in immune responses. However, given that tuft cells are one of the crucial components of non-neuronal cholinergic system, the functions of tuft cell derived acetylcholine (ACh) and the underlying mechanisms remain intricate. Existing evidence demonstrated that tuft cell derived ACh participates in maintaining epithelial homeostasis, modulating airway remodeling, regulating reflexes, promoting muscle constriction, inducing neurogenic inflammation, initiating carcinogenesis and producing ATP. In this review, the ACh biosynthesis pathways and potential clinical applications of tuft cells have been proposed. More importantly, the main pathophysiological roles and the underlying mechanisms of tuft cell derived ACh are summarized and discussed.
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Affiliation(s)
- Jun Pan
- Key Laboratory of Tumor Microenvironment and Immune Therapy of Zhejiang Province, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Cancer Institute (Key Laboratory of Cancer Prevention and Intervention, National Ministry of Education), Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Department of Breast Surgery, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Leyi Zhang
- Key Laboratory of Tumor Microenvironment and Immune Therapy of Zhejiang Province, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Cancer Institute (Key Laboratory of Cancer Prevention and Intervention, National Ministry of Education), Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Department of Breast Surgery, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xuan Shao
- Key Laboratory of Tumor Microenvironment and Immune Therapy of Zhejiang Province, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Cancer Institute (Key Laboratory of Cancer Prevention and Intervention, National Ministry of Education), Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Jian Huang
- Key Laboratory of Tumor Microenvironment and Immune Therapy of Zhejiang Province, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Cancer Institute (Key Laboratory of Cancer Prevention and Intervention, National Ministry of Education), Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Department of Breast Surgery, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
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10
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Sensing Senses: Optical Biosensors to Study Gustation. SENSORS 2020; 20:s20071811. [PMID: 32218129 PMCID: PMC7180777 DOI: 10.3390/s20071811] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 03/19/2020] [Accepted: 03/21/2020] [Indexed: 12/11/2022]
Abstract
The five basic taste modalities, sweet, bitter, umami, salty and sour induce changes of Ca2+ levels, pH and/or membrane potential in taste cells of the tongue and/or in neurons that convey and decode gustatory signals to the brain. Optical biosensors, which can be either synthetic dyes or genetically encoded proteins whose fluorescence spectra depend on levels of Ca2+, pH or membrane potential, have been used in primary cells/tissues or in recombinant systems to study taste-related intra- and intercellular signaling mechanisms or to discover new ligands. Taste-evoked responses were measured by microscopy achieving high spatial and temporal resolution, while plate readers were employed for higher throughput screening. Here, these approaches making use of fluorescent optical biosensors to investigate specific taste-related questions or to screen new agonists/antagonists for the different taste modalities were reviewed systematically. Furthermore, in the context of recent developments in genetically encoded sensors, 3D cultures and imaging technologies, we propose new feasible approaches for studying taste physiology and for compound screening.
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11
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Schneider C, O'Leary CE, Locksley RM. Regulation of immune responses by tuft cells. Nat Rev Immunol 2020; 19:584-593. [PMID: 31114038 DOI: 10.1038/s41577-019-0176-x] [Citation(s) in RCA: 143] [Impact Index Per Article: 35.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Tuft cells are rare, secretory epithelial cells that generated scant immunological interest until contemporaneous reports in 2016 linked tuft cells with type 2 immunity in the small intestine. Tuft cells have the capacity to produce an unusual spectrum of biological effector molecules, including IL-25, eicosanoids implicated in allergy (such as cysteinyl leukotrienes and prostaglandin D2) and the neurotransmitter acetylcholine. In most cases, the extracellular signals controlling tuft cell effector function are unknown, but signal transduction is thought to proceed via canonical, G protein-coupled receptor-dependent pathways involving components of the signalling pathway used by type II taste bud cells to sense sweet, bitter and umami compounds. Tuft cells are ideally positioned as chemosensory sentinels that can detect and relay information from diverse luminal substances via what appear to be stereotyped outputs to initiate both positive and aversive responses through populations of immune and neuronal cells. Despite recent insights, numerous questions remain regarding tuft cell lineage, diversity and effector mechanisms and how tuft cells interface with the immunological niche in the tissues where they reside.
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Affiliation(s)
- Christoph Schneider
- Department of Medicine, University of California-San Francisco, San Francisco, CA, USA
| | - Claire E O'Leary
- Department of Medicine, University of California-San Francisco, San Francisco, CA, USA
| | - Richard M Locksley
- Department of Medicine, University of California-San Francisco, San Francisco, CA, USA. .,Department of Microbiology & Immunology, University of California-San Francisco, San Francisco, CA, USA. .,Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA, USA.
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12
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Hollenhorst MI, Jurastow I, Nandigama R, Appenzeller S, Li L, Vogel J, Wiederhold S, Althaus M, Empting M, Altmüller J, Hirsch AKH, Flockerzi V, Canning BJ, Saliba A, Krasteva‐Christ G. Tracheal brush cells release acetylcholine in response to bitter tastants for paracrine and autocrine signaling. FASEB J 2019; 34:316-332. [DOI: 10.1096/fj.201901314rr] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 10/20/2019] [Accepted: 10/22/2019] [Indexed: 12/20/2022]
Affiliation(s)
| | - Innokentij Jurastow
- Institute of Anatomy and Cell Biology Justus‐Liebig‐University of Giessen Giessen Germany
- Department of Anesthesiology and Intensive Care Medicine (CS) University Hospital Charité Humboldt University of Berlin Berlin Germany
| | - Rajender Nandigama
- Institute of Anatomy and Cell Biology University of Würzburg Würzburg Germany
| | - Silke Appenzeller
- Comprehensive Cancer Centre Mainfranken University of Würzburg Würzburg Germany
| | - Lei Li
- Core Unit SysMed University of Würzburg Würzburg Germany
| | - Jörg Vogel
- Helmholtz Institute for RNA‐based Infection Research (HIRI) Helmholtz‐Centre for Infection Research (HZI) Würzburg Germany
| | - Stephanie Wiederhold
- Institute of Anatomy and Cell Biology Justus‐Liebig‐University of Giessen Giessen Germany
| | - Mike Althaus
- School of Natural and Environmental Sciences Newcastle University Newcastle upon Tyne United Kingdom
| | - Martin Empting
- Department of Drug Design and Optimization (DDOP) Helmholtz‐Institute for Pharmaceutical Research Saarland (HIPS)‐Helmholtz Centre for Infection Research (HZI) Saarbrücken Germany
- Department of Pharmacy Saarland University Saarbrücken Germany
- German Centre for Infection Research (DZIF) Saarbrücken Germany
| | - Janine Altmüller
- Cologne Centre for Genomics University of Cologne Cologne Germany
| | - Anna K. H. Hirsch
- Department of Drug Design and Optimization (DDOP) Helmholtz‐Institute for Pharmaceutical Research Saarland (HIPS)‐Helmholtz Centre for Infection Research (HZI) Saarbrücken Germany
- Department of Pharmacy Saarland University Saarbrücken Germany
- German Centre for Infection Research (DZIF) Saarbrücken Germany
| | - Veit Flockerzi
- Institute of Experimental and Clinical Pharmacology and Toxicology/PZMS Saarland University Homburg Germany
| | - Brendan J. Canning
- Department of Medicine Division of Allergy and Clinical Immunology School of Medicine Johns Hopkins University Baltimore MD USA
| | - Antoine‐Emmanuel Saliba
- Helmholtz Institute for RNA‐based Infection Research (HIRI) Helmholtz‐Centre for Infection Research (HZI) Würzburg Germany
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13
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Nigam AK, Verma N, Srivastava A, Kumari U, Mittal S, Mittal AK. Characterisation of cholinesterases in mucous secretions and their localisation in epidermis of Labeo rohita and Cirrhinus mrigala. FISH PHYSIOLOGY AND BIOCHEMISTRY 2019; 45:1355-1366. [PMID: 31177354 DOI: 10.1007/s10695-019-00663-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 05/24/2019] [Indexed: 06/09/2023]
Abstract
Cholinesterases are multifunctional enzymes and have been associated with diverse physiological functions in addition to their classical role at synapses. In the present study, cholinesterase (ChE) isozymes have been characterised in mucous secretions and their activity has been localised in the epidermis of Labeo rohita and Cirrhinus mrigala. Zymography using specific substrates and inhibitors revealed the presence of two ChE isozymes-ChE-1 and ChE-2. The isozyme ChE-1 was characterised as an atypical butyrylcholinesterase and ChE-2 as a typical acetylcholinesterase in skin mucous secretions of both the fish species. Enzyme histochemical analysis demonstrated the presence of ChE activity in the epidermis of the fish species investigated. In both the fish species, strong ChE activity was observed in the outer-layer epithelial cells, taste buds and neuromasts. The middle and basal layer epithelial cells showed moderate to weak ChE activity. Club cells and mucous goblet cells showed the absence of ChE activity. Characterisation with specific inhibitors indicates that acetylcholinesterase (AChE) was the major cholinesterase type expressed in the epidermis of the two fish species investigated. Immunohistochemical localisation of apoptotic and cell proliferation markers, in addition, revealed high expression of active caspase 3 in the outer-layer epithelial cells, and proliferating cell nuclear antigen (PCNA) in the middle and basal layer epithelial cells. High ChE activity in caspase 3-positive cells in the outer layer of the epidermis and low in PCNA-positive cells in middle and basal layers could point towards the possible involvement of ChEs in cell death and their final extrusion from skin surface.
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Affiliation(s)
- Ashwini Kumar Nigam
- Department of Zoology, Skin Physiology Laboratory, Centre of Advanced Study, Banaras Hindu University, Varanasi, 221005, India
| | - Neeraj Verma
- Department of Zoology, Skin Physiology Laboratory, Centre of Advanced Study, Banaras Hindu University, Varanasi, 221005, India
| | - Ayan Srivastava
- Department of Zoology, Skin Physiology Laboratory, Centre of Advanced Study, Banaras Hindu University, Varanasi, 221005, India
| | - Usha Kumari
- Zoology Section, Mahila Mahavidyalaya, Banaras Hindu University, Varanasi, 221005, India
| | - Swati Mittal
- Department of Zoology, Skin Physiology Laboratory, Centre of Advanced Study, Banaras Hindu University, Varanasi, 221005, India.
| | - Ajay Kumar Mittal
- Former Head of Department of Zoology, Banaras Hindu University, 9, Mani Nagar, Kandawa, Near Chitaipur Crossing, Varanasi, 221106, India
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14
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Tsuno N, Mori T, Ishikawa I, Bando N, Park H, Matsumoto Y, Mori I, Tanaka M, Hirano T, Nakamura Y. Efficacy of rivastigmine transdermal therapy on low food intake in patients with Alzheimer's disease: The Attitude Towards Food Consumption in Alzheimer's Disease Patients Revive with Rivastigmine Effects study. Geriatr Gerontol Int 2019; 19:571-576. [PMID: 30864298 PMCID: PMC6850597 DOI: 10.1111/ggi.13644] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 01/24/2019] [Accepted: 02/03/2019] [Indexed: 12/27/2022]
Abstract
Aim Most patients with Alzheimer's disease (AD) experience poor food intake and/or loss of appetite, which accelerates cognitive impairment. Several reports have shown that rivastigmine improves appetite in AD patients. The present study investigated the efficacy of a rivastigmine transdermal patch for the treatment of low food intake in AD patients. Methods AD patients, recruited through the Attitude Towards Food Consumption in Alzheimer's Disease Patients Revive with Rivastigmine Effects study, were recognized as experiencing either a loss of appetite or poor food intake. A rivastigmine transdermal patch was administered to study participants for 16 weeks. Patients’ food intake, bodyweight, Mini‐Mental State Examination scores and any adverse events were recorded. Results A total of 38 patients with AD (age 86.2 ± 5.4 years) were examined. Their mean Mini‐Mental State Examination score was 10.1 ± 7.0 at baseline. A significant increase in food intake amount (54.9 ± 98.0 g, P < 0.01) and food intake ratio (9.3% ± 17.6%, P < 0.01) was observed by week 1, improvements that were maintained throughout the study duration. A multiple linear regression analysis showed that no independent variables were significantly associated with changes in food intake amount or ratio. Patients in the higher Mini‐Mental State Examination subgroup showed a trend change in food intake amount, although this did not reach statistical significance (P = 0.07). Conclusions The present study suggests that a rivastigmine transdermal patch might improve poor food intake or loss of appetite in patients with AD. Geriatr Gerontol Int 2019; 19: 571–576.
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Affiliation(s)
- Norifumi Tsuno
- Department of Neuropsychiatry, Faculty of Medicine, Kagawa University, Miki-cho, Japan
| | - Takahiro Mori
- Department of Neuropsychiatry, Faculty of Medicine, Kagawa University, Miki-cho, Japan
| | - Ichiro Ishikawa
- Department of Neuropsychiatry, Faculty of Medicine, Kagawa University, Miki-cho, Japan
| | - Nobuyasu Bando
- Department of Mental Health, Kaisei General Hospital, Sakaide, Japan
| | | | - Yoshito Matsumoto
- Nishitakamatsu Neurosurgery and Internal Medicine Clinic, Takamatsu, Japan
| | - Itsuko Mori
- Medical Juridical Person Eisei Hospital, Nakatado, Japan
| | | | | | - Yu Nakamura
- Department of Neuropsychiatry, Faculty of Medicine, Kagawa University, Miki-cho, Japan
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15
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Abstract
Taste buds are the dedicated sensory end organs of taste, comprising a complex and evolving profile of signaling elements. The sensation and ultimate perception of taste depends on the expression of a diverse array of receptors and channels that sense their respective tastes. Receptor regulation is a recognized and well-studied phenomenon in many systems, observed in opioid addiction, insulin resistance and caffeine tolerance. Results from human sensory studies suggest that receptor sensitivity or expression level may decrease after chronic exposure to respective tastants through diet. We review data supporting the theory that taste receptors may become downregulated with exposure to a specific tastant, along with presenting data from a small pilot study, showing the impact of long-term tastant exposure on taste receptor expression in mice. Mice treated with monosodium salt monohydrate (MSG), saccharin and NaCl (typically appetitive tastes) all displayed a significant decrease in mRNA expression for respective umami, sweet and salty receptors/sensory channels. Reduced sensitivity to appetitive tastes may promote overconsumption of foods high in such stimuli.
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16
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Genovese F, Tizzano M. Microvillous cells in the olfactory epithelium express elements of the solitary chemosensory cell transduction signaling cascade. PLoS One 2018; 13:e0202754. [PMID: 30212469 PMCID: PMC6136699 DOI: 10.1371/journal.pone.0202754] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 08/08/2018] [Indexed: 11/18/2022] Open
Abstract
The nasal cavity hosts an array of chemoresponsive cells, including the extended olfactory system and several other cells involved in detection of and responses to irritants. Solitary chemosensory cells (SCCs), which respond to irritants and bacteria, express the transient receptor potential channel TRPM5 an essential element of the taste transduction-signaling cascade. Microvillous cells (MVCs), non-neuronal cells situated in the apical layer of the main olfactory epithelium, also express TRPM5, but their function has not yet been clarified. TRPM5-positive MVCs, like SCCs, show a cholinergic phenotype expressing choline acetyl transferase (ChAT), but none of the other elements of the bitter taste transduction cascade could be detected. We reexamined TRPM5-positive MVCs with more sensitive gene expression and staining techniques to clarify whether they rely only on TRPM5 and ChAT or express other elements of the taste/SCC transduction cascade. Analyzing existing RNA sequencing data from whole olfactory mucosa and isolated olfactory sensory neurons, we determined that several elements of the taste/SCC transduction cascade, including taste receptors, are expressed in the olfactory mucosa in cells other than olfactory sensory neurons. Immunostaining confirmed the presence TRPM5 and ChAT in a subset of cells of the olfactory mucosa, which also showed the expression of PLCB2, gustducin, and T1R3. Specifically, these cells were identified as TRPM5-positive MVCs. Furthermore, we examined whether MVCs are innervated by trigeminal fibers, similarly to SCCs. Using antibodies against trigeminal nerve markers calcitonin gene-related peptide and substance P, we determined that, despite the cholinergic phenotype, most MVCs in the olfactory mucosa lacked consistent trigeminal innervation. Our findings indicate that MVCs, like SCCs, express all the elements of the bitter taste transduction cascade but that, unlike SCCs, they possess only sparse trigeminal innervation. The cholinergic phenotype of MVCs suggests a modulatory function of the surrounding olfactory epithelium, through the release of acetylcholine.
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Affiliation(s)
- Federica Genovese
- Monell Chemical Senses Center, Philadelphia, Pennsylvania, United States of America
| | - Marco Tizzano
- Monell Chemical Senses Center, Philadelphia, Pennsylvania, United States of America
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17
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Kaufman A, Choo E, Koh A, Dando R. Inflammation arising from obesity reduces taste bud abundance and inhibits renewal. PLoS Biol 2018; 16:e2001959. [PMID: 29558472 PMCID: PMC5860696 DOI: 10.1371/journal.pbio.2001959] [Citation(s) in RCA: 83] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 02/12/2018] [Indexed: 01/06/2023] Open
Abstract
Despite evidence that the ability to taste is weakened by obesity and can be rescued with weight loss intervention, few studies have investigated the molecular effects of obesity on the taste system. Taste bud cells undergo continual turnover even in adulthood, exhibiting an average life span of only a few weeks, tightly controlled by a balance of proliferation and cell death. Recent data reveal that an acute inflammation event can alter this balance. We demonstrate that chronic low-grade inflammation brought on by obesity reduces the number of taste buds in gustatory tissues of mice-and is likely the cause of taste dysfunction seen in obese populations-by upsetting this balance of renewal and cell death.
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Affiliation(s)
- Andrew Kaufman
- Department of Food Science, Cornell University, Ithaca, New York, United States of America
| | - Ezen Choo
- Department of Molecular Medicine, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America
| | - Anna Koh
- Department of Food Science, Cornell University, Ithaca, New York, United States of America
| | - Robin Dando
- Department of Food Science, Cornell University, Ithaca, New York, United States of America
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18
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Deckmann K, Rafiq A, Erdmann C, Illig C, Durschnabel M, Wess J, Weidner W, Bschleipfer T, Kummer W. Muscarinic receptors 2 and 5 regulate bitter response of urethral brush cells via negative feedback. FASEB J 2018; 32:2903-2910. [PMID: 29401598 DOI: 10.1096/fj.201700582r] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
We have recently identified a cholinergic chemosensory cell in the urethral epithelium, urethral brush cell (UBC), that, upon stimulation with bitter or bacterial substances, initiates a reflex detrusor activation. Here, we elucidated cholinergic mechanisms that modulate UBC responsiveness. We analyzed muscarinic acetylcholine receptor (M1-5 mAChR) expression by using RT-PCR in UBCs, recorded [Ca2+]i responses to a bitter stimulus in isolated UBCs of wild-type and mAChR-deficient mice, and performed cystometry in all involved strains. The bitter response of UBCs was enhanced by global cholinergic and selective M2 inhibition, diminished by positive allosteric modulation of M5, and unaffected by M1, M3, and M4 mAChR inhibitors. This effect was not observed in M2 and M5 mAChR-deficient mice. In cystometry, M5 mAChR-deficient mice demonstrated signs of detrusor overactivity. In conclusion, M2 and M5 mAChRs attenuate the bitter response of UBC via a cholinergic negative autocrine feedback mechanism. Cystometry suggests that dysfunction, particularly of the M5 receptor, may lead to such symptoms as bladder overactivity.-Deckmann, K., Rafiq, A., Erdmann, C., Illig, C., Durschnabel, M., Wess, J., Weidner, W., Bschleipfer, T., Kummer, W. Muscarinic receptors 2 and 5 regulate bitter response of urethral brush cells via negative feedback.
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Affiliation(s)
- Klaus Deckmann
- Institute for Anatomy and Cell Biology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Amir Rafiq
- Institute for Anatomy and Cell Biology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Christian Erdmann
- Department of Urology, Pediatric Urology, and Andrology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Christian Illig
- Department of Urology, Pediatric Urology, and Andrology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Melanie Durschnabel
- Department of Urology, Pediatric Urology, and Andrology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Jürgen Wess
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland, USA
| | - Wolfgang Weidner
- Department of Urology, Pediatric Urology, and Andrology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Thomas Bschleipfer
- Clinic of Urology, Andrology, and Pediatric Urology, Weiden Hospital/Clinics of Nordoberpfalz AG, Weiden, Germany
| | - Wolfgang Kummer
- Institute for Anatomy and Cell Biology, Justus-Liebig-University Giessen, Giessen, Germany
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Mao YC, Liu PY, Chiang LC, Liao SC, Su HY, Hsieh SY, Yang CC. Bungarus multicinctus multicinctus Snakebite in Taiwan. Am J Trop Med Hyg 2017; 96:1497-1504. [PMID: 28719273 DOI: 10.4269/ajtmh.17-0005] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
AbstractAlthough specific antivenom is available in Taiwan, respiratory failure and general pain frequently accompany Bungarus multicinctus envenomation and there have been few reports on the management of B. multicinctus envenomation. We retrospectively analyzed 44 cases of B. multicinctus bite admitted to Taichung Veterans General Hospital (VGH) or to Taipei VGH. Demographic data, treatment, and outcome of patients with and without respiratory failure were compared. In this study, 20.5% patients had bites without noticeable signs or symptoms of significant envenoming, 27.3% developed respiratory failure, and 27.3% experienced general pain. Bivalent specific antivenom for B. multicinctus and N. atra was administered in all envenomed cases. Respiratory failure occurred 1.5-6.5 hours post-bite and general pain occurred 1-12 hours post-bite. Specific antivenom for B. multicinctus and N. atra at the recommended dose (i.e., 2-4 vials) might not effectively prevent respiratory failure and pain. Respiratory failure, general pain, and autonomic effects after B. multicinctus bite were probably caused, at least partly, by β-bungarotoxin. Although general weakness, ptosis, dysarthria, and dilated pupils were significantly associated with respiratory failure, their predictive value could not be accurately determined in such a retrospective study. Due to the rapid onset of respiratory failure, every suspected envenomed case thus should be closely monitored in the first few hours. We recommend the initial administration of four vials of antivenom in all envenomation cases, and a subsequent four vials be considered if the patient's condition is deteriorating. Prospective evaluation of the antivenom dosing regimen is urgently needed to improve B. multicinctus envenomation treatment.
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Affiliation(s)
- Yan-Chiao Mao
- Division of Clinical Toxicology and Occupational Medicine, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Institute of Environmental and Occupational Health Sciences, School of Medicine, National Yang-Ming University, Taipei, Taiwan.,School of Medicine, National Defense Medical Center, Taipei, Taiwan.,Division of Clinical Toxicology, Department of Emergency Medicine, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Po-Yu Liu
- Division of Infection, Department of Medicine, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Liao-Chun Chiang
- National Health Research Institutes, National Institute of Infectious Diseases and Vaccinology, Miaoli, Taiwan.,National Tsing Hua University, College of Life Sciences, Hsinchu, Taiwan
| | - Shu-Chen Liao
- Department of Emergency Medicine, Chang Guang Memorial Hospital, Taipei, Taiwan.,Institute of Environmental and Occupational Health Sciences, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Hung-Yuan Su
- Department of Emergency Medicine, E-Da Hospital, I-Shou University, Kaohsiung, Taiwan
| | - Szu-Yin Hsieh
- Division of Clinical Toxicology, Department of Emergency Medicine, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Chen-Chang Yang
- Institute of Environmental and Occupational Health Sciences, School of Medicine, National Yang-Ming University, Taipei, Taiwan.,Division of Clinical Toxicology and Occupational Medicine, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
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Chamoun E, Mutch DM, Allen-Vercoe E, Buchholz AC, Duncan AM, Spriet LL, Haines J, Ma DWL. A review of the associations between single nucleotide polymorphisms in taste receptors, eating behaviors, and health. Crit Rev Food Sci Nutr 2017; 58:194-207. [DOI: 10.1080/10408398.2016.1152229] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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21
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Abstract
The past decade has witnessed a consolidation and refinement of the extraordinary progress made in taste research. This Review describes recent advances in our understanding of taste receptors, taste buds, and the connections between taste buds and sensory afferent fibres. The article discusses new findings regarding the cellular mechanisms for detecting tastes, new data on the transmitters involved in taste processing and new studies that address longstanding arguments about taste coding.
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22
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Mori Y, Eguchi K, Yoshii K, Ohtubo Y. Selective expression of muscarinic acetylcholine receptor subtype M3 by mouse type III taste bud cells. Pflugers Arch 2016; 468:2053-2059. [PMID: 27628900 PMCID: PMC5138268 DOI: 10.1007/s00424-016-1879-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 09/06/2016] [Indexed: 10/26/2022]
Abstract
Each taste bud cell (TBC) type responds to a different taste. Previously, we showed that an unidentified cell type(s) functionally expresses a muscarinic acetylcholine (ACh) receptor subtype, M3, and we suggested the ACh-dependent modification of its taste responsiveness. In this study, we found that M3 is expressed by type III TBCs, which is the only cell type that possesses synaptic contacts with taste nerve fibers in taste buds. The application of ACh to the basolateral membrane of mouse fungiform TBCs in situ increased the intracellular Ca2+ concentration in 2.4 ± 1.4 cells per taste bud (mean ± SD, n = 14). After Ca2+ imaging, we supravitally labeled type II cells (phospholipase C β2 [PLCβ2]-immunoreactive cells) with Lucifer yellow CH (LY), a fluorescent dye and investigated the positional relationship between ACh-responding cells and LY-labeled cells. After fixation, the TBCs were immunohistostained to investigate the positional relationships between immunohistochemically classified cells and LY-labeled cells. The overlay of the two positional relationships obtained by superimposing the LY-labeled cells showed that all of the ACh-responding cells were type III cells (synaptosomal-associated protein 25 [SNAP-25]-immunoreactive cells). The ACh responses required no added Ca2+ in the bathing solution. The addition of 1 μM U73122, a phospholipase C inhibitor, decreased the magnitude of the ACh response, whereas that of 1 μM U73343, a negative control, had no effect. These results suggest that type III cells respond to ACh and release Ca2+ from intracellular stores. We also discuss the underlying mechanism of the Ca2+ response and the role of M3 in type III cells.
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Affiliation(s)
- Yusuke Mori
- Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, Kitakyushu, 808-0196, Japan
| | - Kohgaku Eguchi
- Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, Kitakyushu, 808-0196, Japan
| | - Kiyonori Yoshii
- Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, Kitakyushu, 808-0196, Japan
| | - Yoshitaka Ohtubo
- Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, Kitakyushu, 808-0196, Japan.
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23
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Soysal P, Isik AT. Effects of Acetylcholinesterase Inhibitors on Nutritional Status in Elderly Patients with Dementia: A 6-month Follow-up Study. J Nutr Health Aging 2016; 20:398-403. [PMID: 26999239 DOI: 10.1007/s12603-015-0603-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVES Nutritional status is one of the factors that affects disease progression, morbidity and mortality in elderly patients with dementia. The present study aimed to evaluate the effect of acetylcholinesterase inhibitor (AchEI) therapy on nutritional status and food intake in the elderly. DESIGN, SETTING AND PARTICIPANTS Newly diagnosed patients with dementia, who underwent comprehensive geriatric assessment (CGA) and were followed at regular intervals, were retrospectively evaluated. A total of 116 patients, who began to receive AchEI therapy and completed 6-month follow-up period under this treatment, were enrolled in the study. MEASUREMENTS Socio-demographic characteristics and data on comorbidity, polypharmacy, cognitive function, depression, activities of daily living and nutritional status (weight, Body Mass Index (BMI), Mini Nutritional Assessment (MNA)-Short Form) were recorded. RESULTS The mean age of the patients was 78.0±8.9 years. There was no significant difference between baseline and 6-month BMI, weight and MNA scores of dementia patients who received AchEI therapy (p>0.05). With regard to the relation between changes in BMI, weight and MNA on the 6th month versus baseline, and donepezil, rivastigmine and galantamine therapies, no difference was determined (p>0.05). However, no worsening in food intake was observed (kappa: 0.377). When the effects of each AchEI on food intake were compared, food intake in rivastigmine treated patients was not decreased as much as it was in galantamine or donepezil treated patients (p<0.05). CONCLUSION AchEI therapy has no unfavorable effect on nutritional status or weight in elderly patients with different types of dementia, but it seems that food intake is better in those treated by rivastigmine patch.
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Affiliation(s)
- P Soysal
- Prof .Dr. Ahmet Turan ISIK, Dokuz Eylul Universitesi Tıp Fakultesi, Geriatri Bilim Dalı Yaşlanan Beyin ve Demans Unitesi, 35340 Balcova - Izmir / Turkey, Tel: +90 232 412 43 41, Fax:+90 232 412 43 49, E-Mail:
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24
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Recent Advances in Molecular Mechanisms of Taste Signaling and Modifying. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2016; 323:71-106. [PMID: 26944619 DOI: 10.1016/bs.ircmb.2015.12.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The sense of taste conveys crucial information about the quality and nutritional value of foods before it is ingested. Taste signaling begins with taste cells via taste receptors in oral cavity. Activation of these receptors drives the transduction systems in taste receptor cells. Then particular transmitters are released from the taste cells and activate corresponding afferent gustatory nerve fibers. Recent studies have revealed that taste sensitivities are defined by distinct taste receptors and modulated by endogenous humoral factors in a specific group of taste cells. Such peripheral taste generations and modifications would directly influence intake of nutritive substances. This review will highlight current understanding of molecular mechanisms for taste reception, signal transduction in taste bud cells, transmission between taste cells and nerves, regeneration from taste stem cells, and modification by humoral factors at peripheral taste organs.
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Abstract
Levels of obesity have reached epidemic proportions on a global scale, which has led to considerable increases in health problems and increased risk of several diseases, including cardiovascular and pulmonary diseases, cancer and diabetes mellitus. People with obesity consume more food than is needed to maintain an ideal body weight, despite the discrimination that accompanies being overweight and the wealth of available information that overconsumption is detrimental to health. The relationship between energy expenditure and energy intake throughout an individual's lifetime is far more complicated than previously thought. An improved comprehension of the relationships between taste, palatability, taste receptors and hedonic responses to food might lead to increased understanding of the biological underpinnings of energy acquisition, as well as why humans sometimes eat more than is needed and more than we know is healthy. This Review discusses the role of taste receptors in the tongue, gut, pancreas and brain and their hormonal involvement in taste perception, as well as the relationship between taste perception, overeating and the development of obesity.
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Affiliation(s)
- Sara Santa-Cruz Calvo
- Laboratory of Clinical Investigation, National Institute on Aging, NIH, Biomedical Research Center, Room 09B133, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224-6825, USA
| | - Josephine M Egan
- Laboratory of Clinical Investigation, National Institute on Aging, NIH, Biomedical Research Center, Room 09B133, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224-6825, USA
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Dando R, Pereira E, Kurian M, Barro-Soria R, Chaudhari N, Roper SD. A permeability barrier surrounds taste buds in lingual epithelia. Am J Physiol Cell Physiol 2014; 308:C21-32. [PMID: 25209263 DOI: 10.1152/ajpcell.00157.2014] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Epithelial tissues are characterized by specialized cell-cell junctions, typically localized to the apical regions of cells. These junctions are formed by interacting membrane proteins and by cytoskeletal and extracellular matrix components. Within the lingual epithelium, tight junctions join the apical tips of the gustatory sensory cells in taste buds. These junctions constitute a selective barrier that limits penetration of chemosensory stimuli into taste buds (Michlig et al. J Comp Neurol 502: 1003-1011, 2007). We tested the ability of chemical compounds to permeate into sensory end organs in the lingual epithelium. Our findings reveal a robust barrier that surrounds the entire body of taste buds, not limited to the apical tight junctions. This barrier prevents penetration of many, but not all, compounds, whether they are applied topically, injected into the parenchyma of the tongue, or circulating in the blood supply, into taste buds. Enzymatic treatments indicate that this barrier likely includes glycosaminoglycans, as it was disrupted by chondroitinase but, less effectively, by proteases. The barrier surrounding taste buds could also be disrupted by brief treatment of lingual tissue samples with DMSO. Brief exposure of lingual slices to DMSO did not affect the ability of taste buds within the slice to respond to chemical stimulation. The existence of a highly impermeable barrier surrounding taste buds and methods to break through this barrier may be relevant to basic research and to clinical treatments of taste.
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Affiliation(s)
- Robin Dando
- Department of Physiology and Biophysics, Miller School of Medicine, University of Miami, Miami, Florida; and
| | - Elizabeth Pereira
- Department of Physiology and Biophysics, Miller School of Medicine, University of Miami, Miami, Florida; and
| | - Mani Kurian
- Department of Physiology and Biophysics, Miller School of Medicine, University of Miami, Miami, Florida; and
| | - Rene Barro-Soria
- Department of Physiology and Biophysics, Miller School of Medicine, University of Miami, Miami, Florida; and
| | - Nirupa Chaudhari
- Department of Physiology and Biophysics, Miller School of Medicine, University of Miami, Miami, Florida; and Program in Neuroscience, University of Miami, Miami, Florida
| | - Stephen D Roper
- Department of Physiology and Biophysics, Miller School of Medicine, University of Miami, Miami, Florida; and Program in Neuroscience, University of Miami, Miami, Florida
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27
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Bitter triggers acetylcholine release from polymodal urethral chemosensory cells and bladder reflexes. Proc Natl Acad Sci U S A 2014; 111:8287-92. [PMID: 24843119 DOI: 10.1073/pnas.1402436111] [Citation(s) in RCA: 118] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Chemosensory cells in the mucosal surface of the respiratory tract ("brush cells") use the canonical taste transduction cascade to detect potentially hazardous content and trigger local protective and aversive respiratory reflexes on stimulation. So far, the urogenital tract has been considered to lack this cell type. Here we report the presence of a previously unidentified cholinergic, polymodal chemosensory cell in the mammalian urethra, the potential portal of entry for bacteria and harmful substances into the urogenital system, but not in further centrally located parts of the urinary tract, such as the bladder, ureter, and renal pelvis. Urethral brush cells express bitter and umami taste receptors and downstream components of the taste transduction cascade; respond to stimulation with bitter (denatonium), umami (monosodium glutamate), and uropathogenic Escherichia coli; and release acetylcholine to communicate with other cells. They are approached by sensory nerve fibers expressing nicotinic acetylcholine receptors, and intraurethral application of denatonium reflexively increases activity of the bladder detrusor muscle in anesthetized rats. We propose a concept of urinary bladder control involving a previously unidentified cholinergic chemosensory cell monitoring the chemical composition of the urethral luminal microenvironment for potential hazardous content.
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28
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Chaudhari N. Synaptic communication and signal processing among sensory cells in taste buds. J Physiol 2014; 592:3387-92. [PMID: 24665098 DOI: 10.1113/jphysiol.2013.269837] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Taste buds (sensory structures embedded in oral epithelium) show a remarkable diversity of transmitters synthesized and secreted locally. The known transmitters accumulate in a cell type selective manner, with 5-HT and noradrenaline being limited to presynaptic cells, GABA being synthesized in both presynaptic and glial-like cells, and acetylcholine and ATP used for signalling by receptor cells. Each of these transmitters participates in local negative or positive feedback circuits that target particular cell types. Overall, the role of ATP is the best elucidated. ATP serves as a principal afferent transmitter, and also is the key trigger for autocrine positive feedback and paracrine circuits that result in potentiation (via adenosine) or inhibition (via GABA or 5-HT). While many of the cellular receptors and mechanisms for these circuits are known, their impact on sensory detection and perception remains to be elaborated in most instances. This brief review examines what is known, and some of the open questions and controversies surrounding the transmitters and circuits of the taste periphery.
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Affiliation(s)
- Nirupa Chaudhari
- Department of Physiology and Biophysics, Miller School of Medicine, University of Miami, Miami, FL, 33146, USA Program in Neurosciences, Miller School of Medicine, University of Miami, Miami, FL, 33146, USA
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29
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Kinnamon SC, Finger TE. A taste for ATP: neurotransmission in taste buds. Front Cell Neurosci 2013; 7:264. [PMID: 24385952 PMCID: PMC3866518 DOI: 10.3389/fncel.2013.00264] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Accepted: 12/03/2013] [Indexed: 11/13/2022] Open
Abstract
Not only is ATP a ubiquitous source of energy but it is also used widely as an intercellular signal. For example, keratinocytes release ATP in response to numerous external stimuli including pressure, heat, and chemical insult. The released ATP activates purinergic receptors on nerve fibers to generate nociceptive signals. The importance of an ATP signal in epithelial-to-neuronal signaling is nowhere more evident than in the taste system. The receptor cells of taste buds release ATP in response to appropriate stimulation by tastants and the released ATP then activates P2X2 and P2X3 receptors on the taste nerves. Genetic ablation of the relevant P2X receptors leaves an animal without the ability to taste any primary taste quality. Of interest is that release of ATP by taste receptor cells occurs in a non-vesicular fashion, apparently via gated membrane channels. Further, in keeping with the crucial role of ATP as a neurotransmitter in this system, a subset of taste cells expresses a specific ectoATPase, NTPDase2, necessary to clear extracellular ATP which otherwise will desensitize the P2X receptors on the taste nerves. The unique utilization of ATP as a key neurotransmitter in the taste system may reflect the epithelial rather than neuronal origins of the receptor cells.
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Affiliation(s)
- Sue C Kinnamon
- Department of Otolaryngology, Rocky Mountain Taste and Smell Center, University of Colorado School of Medicine Aurora, CO, USA
| | - Thomas E Finger
- Department Cell and Developmental Biology, Rocky Mountain Taste and Smell Center, University of Colorado School of Medicine Aurora, CO, USA
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Hanlon SM, Parris MJ. Previous exposure of predatory fish to a pesticide alters palatability of larval amphibian prey. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2013; 32:2861-2865. [PMID: 24383102 DOI: 10.1002/etc.2380] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Habitat preferences of organisms are reliant on a variety of factors. For amphibians specifically, preferences can depend on factors such as food availability, water quality, and the presence of potential predators. Because some amphibians breed in permanent bodies of water (e.g., ponds), the threat of predation (e.g., from fish) is constant. Thus, some amphibians are unpalatable to many predators, allowing them to coexist in the same habitats. However, the addition of anthropogenic stressors (i.e., pesticides) may alter the perceived palatability of prey items to predators. The authors tested the hypothesis that bluegill fish (Lepomis macrochirus), previously exposed to the pesticide carbaryl, would consume more unpalatable prey (Fowler's toad [Anaxyrus fowleri] tadpoles) than unexposed predators. Carbaryl is a pesticide that attacks the nervous system and is linked to taste sense in organisms. Moreover, the authors conducted an identical test using palatable prey (gray treefrog [Hyla versicolor] tadpoles) and predicted that no change in preference would be observed. In support of the primary hypothesis, bluegill exposed to the highest concentration of carbaryl consumed more A. fowleri tadpoles compared with those exposed to carbaryl at the lowest concentration or water control. Moreover, an effect of carbaryl on predation success on H. versicolor tadpoles was not observed. The present study shows that an anthropogenic stressor (carbaryl) can alter the perceived palatability of noxious prey to fish predators, potentially altering predator-prey relationships in natural settings.
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31
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Dotson CD, Geraedts MCP, Munger SD. Peptide regulators of peripheral taste function. Semin Cell Dev Biol 2013; 24:232-9. [PMID: 23348523 DOI: 10.1016/j.semcdb.2013.01.004] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Accepted: 01/10/2013] [Indexed: 12/25/2022]
Abstract
The peripheral sensory organ of the gustatory system, the taste bud, contains a heterogeneous collection of sensory cells. These taste cells can differ in the stimuli to which they respond and the receptors and other signaling molecules they employ to transduce and encode those stimuli. This molecular diversity extends to the expression of a varied repertoire of bioactive peptides that appear to play important functional roles in signaling taste information between the taste cells and afferent sensory nerves and/or in processing sensory signals within the taste bud itself. Here, we review studies that examine the expression of bioactive peptides in the taste bud and the impact of those peptides on taste functions. Many of these peptides produced in taste buds are known to affect appetite, satiety or metabolism through their actions in the brain, pancreas and other organs, suggesting a functional link between the gustatory system and the neural and endocrine systems that regulate feeding and nutrient utilization.
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Affiliation(s)
- Cedrick D Dotson
- Department of Neuroscience, University of Florida College of Medicine, McKnight Brain Institute, Gainesville, FL 32611, USA
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