1
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Jin SB, Kim HA, Shin JA, Jung NH, Park SY, Hong S, Kong KH. Recombinant expression and tryptophan-assisted analysis of human sweet taste receptor T1R3's extracellular domain in sweetener interaction studies. Prep Biochem Biotechnol 2024; 54:1196-1203. [PMID: 38578840 DOI: 10.1080/10826068.2024.2336985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2024]
Abstract
The human palate can discern multiple tastes; however, it predominantly perceives five fundamental flavors: sweetness, saltiness, sourness, bitterness, and umami. Sweetness is primarily mediated through the sweet taste receptor, a membrane-bound heterodimeric structure comprising T1R2-T1R3. However, unraveling the structural and mechanistic intricacies of the sweet taste receptor has proven challenging. This study aimed to address this knowledge gap by expressing an extracellular N-terminal domain encompassing the cysteine-rich domain of human hT1R3 (hT1R3-TMD) in Escherichia coli. The expressed protein was obtained as inclusion bodies, purified by metal affinity chromatography, and refolded using the dilution-refolding method. Through rigorous analysis, we confirmed the successful refolding of hT1R3-TMD and elucidated its structural characteristics using circular dichroism spectroscopy. Notably, the refolded protein was found to exist as either a monomer or a dimer, depending on its concentration. A tryptophan fluorescence quenching assay revealed that the dissociation constants for sucrose, sucralose, and brazzein were >9500 μM, 2380 μM and 14.3 μM, respectively. Our findings highlight the utility of this E. coli expression system for producing functional hT1R3-TMD for investigations and demonstrate the efficacy of the tryptophan fluorescence quenching assay in revealing complex interactions between sweet taste receptors and various sweeteners.
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Affiliation(s)
- Soo-Bin Jin
- Department of Chemistry, College of Natural Sciences, Chung-Ang University, Seoul, Korea
| | - Hyun-A Kim
- Department of Chemistry, College of Natural Sciences, Chung-Ang University, Seoul, Korea
| | - Ji-Ae Shin
- Department of Chemistry, College of Natural Sciences, Chung-Ang University, Seoul, Korea
| | - Na-Hee Jung
- Department of Chemistry, College of Natural Sciences, Chung-Ang University, Seoul, Korea
| | - Seo-Young Park
- Department of Chemistry, College of Natural Sciences, Chung-Ang University, Seoul, Korea
| | - Sungguan Hong
- Department of Chemistry, College of Natural Sciences, Chung-Ang University, Seoul, Korea
| | - Kwang-Hoon Kong
- Department of Chemistry, College of Natural Sciences, Chung-Ang University, Seoul, Korea
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2
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Wang Y, Chang S, Lu S, Tong M, Kong F, Liu B. The sweet taste receptors in Lemuriformes respond to aspartame, a non-nutritive sweetener and critical residues mediating their taste. Biochimie 2024:S0300-9084(24)00164-0. [PMID: 38996999 DOI: 10.1016/j.biochi.2024.07.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Revised: 07/02/2024] [Accepted: 07/09/2024] [Indexed: 07/14/2024]
Abstract
Aspartame is a high potency artificial sweetener which is popularly used in foods and beverages. The species-dependent sweet taste toward aspartame has not been completely understood. In a recent publication, we reported that the prosimians Lemuriformes species, which are proposed as aspartame nontasters, could taste aspartame based on the sequence and structure analysis. In this study, by mutagenesis, cell-based functional analysis and molecular simulations, we reveal that Lemuriformes species can respond to aspartame at the cell-based receptor activity level. Furthermore, it is proved that the conserved critical residues D142 and S40 mediate the species-dependent sweet taste toward aspartame. This research provides a deeper insight on the species taste, structure-activity relationship and evolution for eliciting the sweetness of this important synthetic sweetener.
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Affiliation(s)
- Yuqing Wang
- Department of Food Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, Shandong, 250353, China
| | - Shiyu Chang
- Tobacco Research Institute, Laboratory of Tobacco and Aromatic Plants Quality and Safety Risk Assessment, Ministry of Agriculture and Rural Affairs, Chinese Academy of Agricultural Sciences, Qingdao, 266101, China
| | - Shangyang Lu
- Department of Food Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, Shandong, 250353, China
| | - Mingqiong Tong
- School of Medicine and Nursing, Dezhou University, Dezhou, Shandong, 253023, China
| | - Fanyu Kong
- Tobacco Research Institute, Laboratory of Tobacco and Aromatic Plants Quality and Safety Risk Assessment, Ministry of Agriculture and Rural Affairs, Chinese Academy of Agricultural Sciences, Qingdao, 266101, China
| | - Bo Liu
- Department of Food Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, Shandong, 250353, China.
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3
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Yoshida R, Ninomiya Y. Mechanisms and Functions of Sweet Reception in Oral and Extraoral Organs. Int J Mol Sci 2024; 25:7398. [PMID: 39000505 PMCID: PMC11242429 DOI: 10.3390/ijms25137398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Revised: 06/27/2024] [Accepted: 07/03/2024] [Indexed: 07/16/2024] Open
Abstract
The oral detection of sugars relies on two types of receptor systems. The first is the G-protein-coupled receptor TAS1R2/TAS1R3. When activated, this receptor triggers a downstream signaling cascade involving gustducin, phospholipase Cβ2 (PLCβ2), and transient receptor potential channel M5 (TRPM5). The second type of receptor is the glucose transporter. When glucose enters the cell via this transporter, it is metabolized to produce ATP. This ATP inhibits the opening of KATP channels, leading to cell depolarization. Beside these receptor systems, sweet-sensitive taste cells have mechanisms to regulate their sensitivity to sweet substances based on internal and external states of the body. Sweet taste receptors are not limited to the oral cavity; they are also present in extraoral organs such as the gastrointestinal tract, pancreas, and brain. These extraoral sweet receptors are involved in various functions, including glucose absorption, insulin release, sugar preference, and food intake, contributing to the maintenance of energy homeostasis. Additionally, sweet receptors may have unique roles in certain organs like the trachea and bone. This review summarizes past and recent studies on sweet receptor systems, exploring the molecular mechanisms and physiological functions of sweet (sugar) detection in both oral and extraoral organs.
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Affiliation(s)
- Ryusuke Yoshida
- Department of Oral Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama 700-8525, Japan
- Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama 700-8558, Japan
| | - Yuzo Ninomiya
- Department of Oral Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama 700-8525, Japan
- Graduate School of Dental Science, Kyushu University, Fukuoka 812-8582, Japan
- Monell Chemical Senses Center, Philadelphia, PA 19104, USA
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4
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Behrens M. The Growing Complexity of Human Bitter Taste Perception. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:14530-14534. [PMID: 38914424 PMCID: PMC11228980 DOI: 10.1021/acs.jafc.4c02465] [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: 03/20/2024] [Revised: 06/13/2024] [Accepted: 06/13/2024] [Indexed: 06/26/2024]
Abstract
Human bitter perception is important for the identification of potentially harmful substances in food. For quite some years, research focused on the identification of activators for ∼25 human bitter taste receptors. The discovery of antagonists as well as increasing knowledge about agonists of different efficacies has substantially added to the intricacy of bitter taste perception. This article seeks to raise awareness for an underestimated new level of complexity when compound mixtures or even whole food items are assessed for their bitter taste.
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Affiliation(s)
- Maik Behrens
- Leibniz Institute for Food
Systems Reception, Technical University
of Munich, 85354 Freising, Germany
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5
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Ortiz AJ, Martín V, Romero D, Guillamon A, Giraldo J. Time-dependent ligand-receptor binding kinetics and functionality in a heterodimeric receptor model. Biochem Pharmacol 2024; 225:116299. [PMID: 38763260 DOI: 10.1016/j.bcp.2024.116299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Revised: 05/05/2024] [Accepted: 05/16/2024] [Indexed: 05/21/2024]
Abstract
GPCRs heteromerize both in CNS and non-CNS regions. The cell uses receptor heteromerization to modulate receptor functionality and to provide fine tuning of receptor signaling. In order for pharmacologists to explore these mechanisms for therapeutic purposes, quantitative receptor models are needed. We have developed a time-dependent model of the binding kinetics and functionality of a preformed heterodimeric receptor involving two drugs. Two cases were considered: both or only one of the drugs are in excess with respect to the total concentration of the receptor. The latter case can be applied to those situations in which a drug causes unwanted side effects that need to be reduced by decreasing its concentration. The required efficacy can be maintained by the allosteric effects mutually exerted by the two drugs in the two-drug combination system. We discuss this concept assuming that the drug causing unwanted side effects is an opioid and that analgesia is the therapeutic effect. As additional points, allosteric modulation by endogenous compounds and synthetic bivalent ligands was included in the study. Receptor heteromerization offers a mechanistic understanding and quantification of the pharmacological effects elicited by combinations of two drugs at different doses and with different efficacies and cooperativity effects, thus providing a conceptual framework for drug combination therapy.
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Affiliation(s)
- Antonio J Ortiz
- Laboratory of Molecular Neuropharmacology and Bioinformatics, Unitat de Bioestadística and Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain; Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, Spain; Unitat de Neurociència Traslacional, Parc Taulí Hospital Universitari, Institut d'Investigació i Innovació Parc Taulí (I3PT), Institut de Neurociències, Universitat Autònoma de Barcelona, Spain.
| | - Víctor Martín
- Laboratory of Molecular Neuropharmacology and Bioinformatics, Unitat de Bioestadística and Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain; Departament de Matemàtiques, EPSEB, Universitat Politècnica de Catalunya, 08028 Barcelona, Spain.
| | - David Romero
- Centre de Recerca Matemàtica, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain.
| | - Antoni Guillamon
- Departament de Matemàtiques, EPSEB, Universitat Politècnica de Catalunya, 08028 Barcelona, Spain; IMTech, Universitat Politècnica de Catalunya, 08028 Barcelona, Spain; Centre de Recerca Matemàtica, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain.
| | - Jesús Giraldo
- Laboratory of Molecular Neuropharmacology and Bioinformatics, Unitat de Bioestadística and Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain; Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, Spain; Unitat de Neurociència Traslacional, Parc Taulí Hospital Universitari, Institut d'Investigació i Innovació Parc Taulí (I3PT), Institut de Neurociències, Universitat Autònoma de Barcelona, Spain.
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6
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Zhu Z, Zhang W, Li Z, Zhao W, Liu C, Zhu B, He P, Tang S, Wu Y, Yang J, Yang Q. Rethinking Sweetener Discovering: Multiparameter Modeling of Molecular Docking Results between the T1R2-T1R3 Receptor and Compounds with Different Tastes. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:7336-7343. [PMID: 38508871 DOI: 10.1021/acs.jafc.4c00407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/22/2024]
Abstract
Molecular docking has been widely applied in the discovery of new sweeteners, yet the interpretation of computational results sometimes remains difficult. Here, the interaction between the T1R2-T1R3 sweet taste receptor and 66 tasting compounds, including 26 sweet, 19 bitter, and 21 sour substances was investigated by batch molecular docking processes. Statistical analysis of the docking results generated two novel methods of interpreting taste properties. Quantitative correlation between relative sweetness (RS) and docking results created a multiparameter model to predict sweetness intensity, whose correlation coefficient r = 0.74 is much higher than r = 0.17 for the linear correlation model between sweetness and binding energy. The improved correlation indicated that docking results besides binding energy contain undiscovered information about the ligand-protein interaction. Qualitative discriminant analysis of different tasting molecules generated an uncorrelated linear discriminant analysis (UDLA) model, which achieved an overall 93.1% accuracy in discriminating the taste of molecules, with specific accuracy for verifying sweet, bitter, and sour compounds reaching 88.0%, 92.1%, and 100%. These unprecedented models provide a unique perspective for interpreting computational results and may inspire future research on sweetener discovery.
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Affiliation(s)
- Zhiyang Zhu
- R&D Center, China Tobacco Yunnan Industrial Co., Ltd., Hongjin Road 367, Kunming 650224, China
| | - Wei Zhang
- R&D Center, China Tobacco Yunnan Industrial Co., Ltd., Hongjin Road 367, Kunming 650224, China
| | - Zhenjie Li
- R&D Center, China Tobacco Yunnan Industrial Co., Ltd., Hongjin Road 367, Kunming 650224, China
| | - Wei Zhao
- R&D Center, China Tobacco Yunnan Industrial Co., Ltd., Hongjin Road 367, Kunming 650224, China
| | - Chunbo Liu
- R&D Center, China Tobacco Yunnan Industrial Co., Ltd., Hongjin Road 367, Kunming 650224, China
| | - Baokun Zhu
- R&D Center, China Tobacco Yunnan Industrial Co., Ltd., Hongjin Road 367, Kunming 650224, China
| | - Pei He
- R&D Center, China Tobacco Yunnan Industrial Co., Ltd., Hongjin Road 367, Kunming 650224, China
| | - Shiyun Tang
- R&D Center, China Tobacco Yunnan Industrial Co., Ltd., Hongjin Road 367, Kunming 650224, China
| | - Yiqin Wu
- R&D Center, China Tobacco Yunnan Industrial Co., Ltd., Hongjin Road 367, Kunming 650224, China
| | - Ji Yang
- R&D Center, China Tobacco Yunnan Industrial Co., Ltd., Hongjin Road 367, Kunming 650224, China
| | - Qianxu Yang
- R&D Center, China Tobacco Yunnan Industrial Co., Ltd., Hongjin Road 367, Kunming 650224, China
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7
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An JP, Wang Y, Munger SD, Tang X. A review on natural sweeteners, sweet taste modulators and bitter masking compounds: structure-activity strategies for the discovery of novel taste molecules. Crit Rev Food Sci Nutr 2024:1-24. [PMID: 38494695 DOI: 10.1080/10408398.2024.2326012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Growing demand for the tasty and healthy food has driven the development of low-calorie sweeteners, sweet taste modulators, and bitter masking compounds originated from natural sources. With the discovery of human taste receptors, increasing numbers of sweet taste modulators have been identified through human taste response and molecular docking techniques. However, the discovery of novel taste-active molecules in nature can be accelerated by using advanced spectrometry technologies based on structure-activity relationships (SARs). SARs explain why structurally similar compounds can elicit similar taste qualities. Given the characterization of structural information from reported data, strategies employing SAR techniques to find structurally similar compounds become an innovative approach to expand knowledge of sweeteners. This review aims to summarize the structural patterns of known natural non-nutritive sweeteners, sweet taste enhancers, and bitter masking compounds. Innovative SAR-based approaches to explore sweetener derivatives are also discussed. Most sweet-tasting flavonoids belong to either the flavanonols or the dihydrochalcones and known bitter masking molecules are flavanones. Based on SAR findings that structural similarities are related to the sensory properties, innovative methodologies described in this paper can be applied to screen and discover the derivatives of taste-active compounds or potential taste modulators.
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Affiliation(s)
- Jin-Pyo An
- Food Science and Human Nutrition, Citrus Research and Education Center, University of Florida, Lake Alfred, FL, USA
| | - Yu Wang
- Food Science and Human Nutrition, Citrus Research and Education Center, University of Florida, Lake Alfred, FL, USA
| | - Steven D Munger
- Center for Smell and Taste, Department of Pharmacology and Therapeutics, Department of Otolaryngology, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Xixuan Tang
- Food Science and Human Nutrition, Citrus Research and Education Center, University of Florida, Lake Alfred, FL, USA
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8
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Ma D, Hu M, Yang X, Liu Q, Ye F, Cai W, Wang Y, Xu X, Chang S, Wang R, Yang W, Ye S, Su N, Fan M, Xu H, Guo J. Structural basis for sugar perception by Drosophila gustatory receptors. Science 2024; 383:eadj2609. [PMID: 38305684 DOI: 10.1126/science.adj2609] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 01/17/2024] [Indexed: 02/03/2024]
Abstract
Insects rely on a family of seven transmembrane proteins called gustatory receptors (GRs) to encode different taste modalities, such as sweet and bitter. We report structures of Drosophila sweet taste receptors GR43a and GR64a in the apo and sugar-bound states. Both GRs form tetrameric sugar-gated cation channels composed of one central pore domain (PD) and four peripheral ligand-binding domains (LBDs). Whereas GR43a is specifically activated by the monosaccharide fructose that binds to a narrow pocket in LBDs, disaccharides sucrose and maltose selectively activate GR64a by binding to a larger and flatter pocket in LBDs. Sugar binding to LBDs induces local conformational changes, which are subsequently transferred to the PD to cause channel opening. Our studies reveal a structural basis for sugar recognition and activation of GRs.
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Affiliation(s)
- Demin Ma
- Department of Biophysics and Department of Neurology of the Fourth Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
- Nanhu Brain-Computer Interface Institute, Hangzhou 311100, China
| | - Meiqin Hu
- Department of Neurology and Department of Cardiology, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou 310058, China
- New Cornerstone Science Laboratory, Liangzhu Laboratory and School of Basic Medical Sciences, Zhejiang University, Hangzhou 311121, China
| | - Xiaotong Yang
- Department of Neurology and Department of Cardiology, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou 310058, China
- New Cornerstone Science Laboratory, Liangzhu Laboratory and School of Basic Medical Sciences, Zhejiang University, Hangzhou 311121, China
| | - Qiang Liu
- Department of Neurology and Department of Cardiology, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou 310058, China
- New Cornerstone Science Laboratory, Liangzhu Laboratory and School of Basic Medical Sciences, Zhejiang University, Hangzhou 311121, China
| | - Fan Ye
- Department of Biophysics and Department of Neurology of the Fourth Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
- Nanhu Brain-Computer Interface Institute, Hangzhou 311100, China
| | - Weijie Cai
- Department of Neurology and Department of Cardiology, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou 310058, China
- New Cornerstone Science Laboratory, Liangzhu Laboratory and School of Basic Medical Sciences, Zhejiang University, Hangzhou 311121, China
| | - Yong Wang
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Ximing Xu
- Marine Biomedical Institute of Qingdao, School of Pharmacy and Medicine, Ocean University of China, Qingdao, Shandong 266100, China
| | - Shenghai Chang
- Center of Cryo-Electron Microscopy, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Ruiying Wang
- CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
| | - Wei Yang
- Department of Biophysics and Department of Neurology of the Fourth Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
- NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Science and Brain-machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Sheng Ye
- Tianjin Key Laboratory of Function and Application of Biological Macromolecular Structures, School of Life Sciences, Tianjin University, Tianjin 300072, China
| | - Nannan Su
- International Institutes of Medicine, The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang 322000, China
| | - Minrui Fan
- CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
| | - Haoxing Xu
- Department of Neurology and Department of Cardiology, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou 310058, China
- New Cornerstone Science Laboratory, Liangzhu Laboratory and School of Basic Medical Sciences, Zhejiang University, Hangzhou 311121, China
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Jiangtao Guo
- Department of Biophysics and Department of Neurology of the Fourth Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
- Nanhu Brain-Computer Interface Institute, Hangzhou 311100, China
- NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Science and Brain-machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
- State Key Laboratory of Plant Environmental Resilience, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
- Department of Cardiology, Key Laboratory of Cardiovascular Intervention and Regenerative Medicine of Zhejiang Province, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310016, China
- Cancer Center, Zhejiang University, Hangzhou, Zhejiang 310058, China
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9
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Yang J, Myers J, Slaughter MM. Saccharin and aspartame excite rat retinal neurons. FRONTIERS IN OPHTHALMOLOGY 2023; 3:1273575. [PMID: 38983093 PMCID: PMC11182259 DOI: 10.3389/fopht.2023.1273575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Accepted: 09/19/2023] [Indexed: 07/11/2024]
Abstract
Retinal sensitivity to a variety of artificial sweeteners was tested by monitoring changes in internal free calcium in isolated retinal neurons using Fluo3. Several ligands, including aspartame and saccharin elevated internal free calcium. The effects of these ligands were mediated by both ligand-gated membrane channels and G-protein coupled receptors. We explored the receptors responsible for this phenomenon. Surprisingly, mRNA for subunits of the sweet taste receptor dimer (T1R2 and T1R3) were found in retina. Interestingly, knockdown of T1R2 reduced the response to saccharin but not aspartame. But TRPV1 channel antagonists suppressed the responses to aspartame. The results indicate that artificial sweeteners can increase internal free calcium in the retinal neurons through multiple pathways. Furthermore, aspartame reduced the b-wave, but not the a-wave, of the electroretinogram, indicating disruption of communication between photoreceptors and second order neurons.
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Affiliation(s)
| | | | - Malcolm M. Slaughter
- Department of Physiology and Biophysics, Jacobs School of Medicine and Biomedical Sciences, The State University of New York at Buffalo, Buffalo, NY, United States
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10
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Yoshida A, Ito A, Yasui N, Yamashita A. Direct binding of calmodulin to the cytosolic C-terminal regions of sweet/umami taste receptors. J Biochem 2023; 174:451-459. [PMID: 37527916 PMCID: PMC11033526 DOI: 10.1093/jb/mvad060] [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: 05/30/2023] [Revised: 07/15/2023] [Accepted: 07/26/2023] [Indexed: 08/03/2023] Open
Abstract
Sweet and umami taste receptors recognize chemicals such as sugars and amino acids on their extracellular side and transmit signals into the cytosol of the taste cell. In contrast to ligands that act on the extracellular side of these receptors, little is known regarding the molecules that regulate receptor functions within the cytosol. In this study, we analysed the interaction between sweet and umami taste receptors and calmodulin, a representative Ca2+-dependent cytosolic regulatory protein. High prediction scores for calmodulin binding were observed on the C-terminal cytosolic side of mouse taste receptor type 1 subunit 3 (T1r3), a subunit that is common to both sweet and umami taste receptors. Pull-down assay and surface plasmon resonance analyses showed different affinities of calmodulin to the C-terminal tails of distinct T1r subtypes. Furthermore, we found that T1r3 and T1r2 showed the highest and considerable binding to calmodulin, whereas T1r1 showed weaker binding affinity. Finally, the binding of calmodulin to T1rs was consistently higher in the presence of Ca2+ than in its absence. The results suggested a possibility of the Ca2+-dependent feedback regulation process of sweet and umami taste receptor signaling by calmodulin.
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Affiliation(s)
- Atsuki Yoshida
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Ayumi Ito
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Norihisa Yasui
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Atsuko Yamashita
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
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11
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Rayo-Morales R, Segura-Carretero A, Borras-Linares I, Garcia-Burgos D. Suppression of sweet taste-related responses by plant-derived bioactive compounds and eating. Part II: A systematic review in animals. Heliyon 2023; 9:e20511. [PMID: 37860570 PMCID: PMC10582302 DOI: 10.1016/j.heliyon.2023.e20511] [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: 09/27/2023] [Accepted: 09/27/2023] [Indexed: 10/21/2023] Open
Abstract
This article, the second in a two-part series, continues the discussion on the nature of the relationship between the level of sweet taste suppression and eating behaviour, but in animal rather human subjects. In particular, the aim was to review the scientific literature on the impact that bioactive compounds that decrease oral sweet sensations have on intake, preference and physiological status in preclinical studies. This review was registered in the International Prospective Register of Systematic Reviews and conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and the Scottish Intercollegiate Guidelines Network and covered original papers included in Web of Science, PubMed, Scopus, Food Science Source and Food Science and technology abstracts. We identified 28 peer-reviewed English-language studies that fit the topic and met the inclusion criteria. We identified three plant species, Gymnema sylvestre, Hovenia dulcis, and Ziziphus jujuba, that possess acute sweetness-inhibitory properties. When administered orally, these plants reduced neural responses to sweet stimuli and decreased consumption. However, studies on the longer-term effects of antisweet activity remain to be conducted. Translating the valuable insights into the mechanisms underlying the relationship between sweet taste impairment and eating behaviour into practical clinical applications are discussed.
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Affiliation(s)
- Raquel Rayo-Morales
- Department of Analytical Chemistry, Faculty of Science, University of Granada, 18071 Granada, Spain
- Department of Psychobiology, Institute of Neurosciences, Centre for Biomedical Research, University of Granada, 18010, Granada, Spain
| | - Antonio Segura-Carretero
- Department of Analytical Chemistry, Faculty of Science, University of Granada, 18071 Granada, Spain
| | - Isabel Borras-Linares
- Department of Analytical Chemistry, Faculty of Science, University of Granada, 18071 Granada, Spain
| | - David Garcia-Burgos
- Department of Psychobiology, Institute of Neurosciences, Centre for Biomedical Research, University of Granada, 18010, Granada, Spain
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12
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Ball L, Bauer J, Krautwurst D. Heterodimerization of Chemoreceptors TAS1R3 and mGlu 2 in Human Blood Leukocytes. Int J Mol Sci 2023; 24:12942. [PMID: 37629122 PMCID: PMC10454557 DOI: 10.3390/ijms241612942] [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: 06/15/2023] [Revised: 08/08/2023] [Accepted: 08/15/2023] [Indexed: 08/27/2023] Open
Abstract
The expression of canonical chemosensory receptors of the tongue, such as the heteromeric sweet taste (TAS1R2/TAS1R3) and umami taste (TAS1R1/TAS1R3) receptors, has been demonstrated in many extra-oral cells and tissues. Gene expression studies have revealed transcripts for all TAS1 and metabotropic glutamate (mGlu) receptors in different types of immune cells, where they are involved, for example, in the chemotaxis of human neutrophils and the protection of T cells from activation-induced cell death. Like other class-C G protein-coupling receptors (GPCRs), TAS1Rs and mGlu receptors form heteromers within their families. Since mGlu receptors and TAS1R1/TAS1R3 share the same ligand, monosodium glutamate (MSG), we hypothesized their hitherto unknown heteromerization across receptor families in leukocytes. Here we show, by means of immunocytochemistry and co-IP/Western analysis, that across class-C GPCR families, mGlu2 and TAS1R3 co-localize and heterodimerize in blood leukocytes. Expressing the recombinant receptors in HEK-293 cells, we validated their heterodimerization by bioluminescence resonance energy transfer. We demonstrate MSG-induced, mGlu2/TAS1R3 heteromer-dependent gain-of-function and pertussis toxin-sensitive signaling in luminescence assays. Notably, we show that mGlu2/TAS1R3 is necessary and sufficient for MSG-induced facilitation of N-formyl-methionyl-leucyl-phenylalanine-stimulated IL-8 secretion in neutrophils, using receptor-specific antagonists. In summary, our results demonstrate mGlu2/TAS1R3 heterodimerization in leukocytes, suggesting cellular function-tailored chemoreceptor combinations to modulate cellular immune responses.
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Affiliation(s)
- Lena Ball
- TUM School of Life Sciences, Technical University of Munich, Alte Akademie 8a, 85354 Freising, Germany;
- Leibniz-Institute for Food Systems Biology at the Technical University of Munich, Lise-Meitner-Str. 34, 85354 Freising, Germany;
| | - Julia Bauer
- Leibniz-Institute for Food Systems Biology at the Technical University of Munich, Lise-Meitner-Str. 34, 85354 Freising, Germany;
| | - Dietmar Krautwurst
- Leibniz-Institute for Food Systems Biology at the Technical University of Munich, Lise-Meitner-Str. 34, 85354 Freising, Germany;
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13
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Li M, Zhang X, Zhu Y, Zhang X, Cui Z, Zhang N, Sun Y, Yang Z, Wang W, Wang C, Zhang Y, Liu Y, Qing G. Identifying Umami Peptides Specific to the T1R1/T1R3 Receptor via Phage Display. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:12004-12014. [PMID: 37523494 DOI: 10.1021/acs.jafc.3c02471] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Abstract
Umami peptides are small molecular weight oligopeptides that play a role in umami taste attributes. However, the identification of umami peptides is easily limited by environmental conditions, and the abundant source and high chromatographic separation efficiency remain difficult. Herein, we report a robust strategy based on a phage random linear heptapeptide library that targets the T1R1-Venus flytrap domain (T1R1-VFT). Two candidate peptides (MTLERPW and MNLHLSF) were readily identified with high affinity for T1R1-VFT binding (KD of MW-7 and MF-7 were 790 and 630 nM, respectively). The two peptides exhibited umami taste and significantly enhanced the umami intensity when added to the monosodium glutamate solution. Overall, this strategy shows that umami peptides could be developed via phage display technology for the first time. The phage display platform has a promising application to discover other taste peptides with affinity for taste receptors of interest and has more room for improvement in the future.
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Affiliation(s)
- Mingyang Li
- Department of Food Science & Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, PR China
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, PR China
| | - Xiaoyu Zhang
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, PR China
| | - Yiwen Zhu
- Department of Food Science & Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Xiancheng Zhang
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, PR China
| | - Zhiyong Cui
- Department of Food Science & Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Ninglong Zhang
- Department of Food Science & Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Yue Sun
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, PR China
| | - Zhiying Yang
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, PR China
| | - Wenli Wang
- Department of Food Science & Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Cunli Wang
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, PR China
| | - Yin Zhang
- Key Laboratory of Meat Processing of Sichuan, Chengdu University, Chengdu 610106, PR China
| | - Yuan Liu
- Department of Food Science & Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Guangyan Qing
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, PR China
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14
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Wang W, Mu Q, Feng X, Liu W, Xu H, Chen X, Shi F, Gong T. Sweet Taste Receptor T1R3 Expressed in Leydig Cells Is Closely Related to Homeostasis of the Steroid Hormone Metabolism Profile. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:7791-7802. [PMID: 37186581 DOI: 10.1021/acs.jafc.3c01110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Taste receptor type 1 subunit 3 (T1R3) is initially expressed in mammal tongue for recognition and response of sweet/umami tastants and is critical to nutrient absorption, even endocrine. In this study, down-regulation of related steroidogenic enzymes such as StAR, 3β-HSD, CYP17A1, and 17β-HSD with the decrease of T1R3 expression was found in Leydig cells treated by a T1R3 inhibitor (lactisole). The abundances of progesterone, 17a-hydroxyprogesterone, androstenedione, testosterone, and deoxycorticosterone were down-regulated by 2.3, 3.5, 1.4, 1.6, and 2.2 times, respectively, after T1R3 inhibition. In addition, opposite results were found in saccharin sodium treatment. T1R3 activation contributed to intracellular cyclic adenosine monophosphate (cAMP) accumulation (14.41 ± 0.58 vs 20.21 ± 0.65) and increased testosterone (20.31 ± 3.49 vs 50.01 ± 7.44) and steroidogenic metabolite levels. Coadministration of human chorionic gonadotropin and saccharin sodium resulted in elevating the testosterone and cAMP levels and enhancing the expression levels of steroidogenic-related factors. Similarly, intratesticular injection of lactisole and saccharin sodium further confirmed that T1R3 inhibition/activation affected the expression of related steroidogenic enzymes and the testosterone levels in mice. The above findings suggest that T1R3 plays a role in testicular steroidogenesis.
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Affiliation(s)
- Weiyong Wang
- Key Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, Ministry of Education, Guizhou University, Guiyang 550025, Guizhou Province, China
- Guizhou Provincial Key Laboratory of Animal Genetics, Breeding and Reproduction, Guiyang 550025, Guizhou Province, China
- College of Animal Science, Guizhou University, Guiyang 550025, Guizhou Province, China
| | - Qi Mu
- Key Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, Ministry of Education, Guizhou University, Guiyang 550025, Guizhou Province, China
- Guizhou Provincial Key Laboratory of Animal Genetics, Breeding and Reproduction, Guiyang 550025, Guizhou Province, China
- College of Animal Science, Guizhou University, Guiyang 550025, Guizhou Province, China
| | - Xianzhou Feng
- Key Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, Ministry of Education, Guizhou University, Guiyang 550025, Guizhou Province, China
- Guizhou Provincial Key Laboratory of Animal Genetics, Breeding and Reproduction, Guiyang 550025, Guizhou Province, China
- College of Animal Science, Guizhou University, Guiyang 550025, Guizhou Province, China
| | - Wenjiao Liu
- Key Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, Ministry of Education, Guizhou University, Guiyang 550025, Guizhou Province, China
- Guizhou Provincial Key Laboratory of Animal Genetics, Breeding and Reproduction, Guiyang 550025, Guizhou Province, China
- College of Animal Science, Guizhou University, Guiyang 550025, Guizhou Province, China
| | - Houqiang Xu
- Key Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, Ministry of Education, Guizhou University, Guiyang 550025, Guizhou Province, China
- Guizhou Provincial Key Laboratory of Animal Genetics, Breeding and Reproduction, Guiyang 550025, Guizhou Province, China
- College of Animal Science, Guizhou University, Guiyang 550025, Guizhou Province, China
| | - Xiang Chen
- Key Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, Ministry of Education, Guizhou University, Guiyang 550025, Guizhou Province, China
- Guizhou Provincial Key Laboratory of Animal Genetics, Breeding and Reproduction, Guiyang 550025, Guizhou Province, China
- College of Animal Science, Guizhou University, Guiyang 550025, Guizhou Province, China
| | - Fangxiong Shi
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, Jiangsu Province, China
| | - Ting Gong
- Key Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, Ministry of Education, Guizhou University, Guiyang 550025, Guizhou Province, China
- Guizhou Provincial Key Laboratory of Animal Genetics, Breeding and Reproduction, Guiyang 550025, Guizhou Province, China
- College of Animal Science, Guizhou University, Guiyang 550025, Guizhou Province, China
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15
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Cheng K, Wang S, Wang Y, Bao Y, Gao P, Lei L, Liang H, Zhang S, Dong L. Modification of a Novel Umami Octapeptide with Trypsin Hydrolysis Sites via Homology Modeling and Molecular Docking. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:5326-5336. [PMID: 36939140 DOI: 10.1021/acs.jafc.2c08646] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Increasing the copy number of peptides is an effective method to genetically engineer recombinant expression and obtain umami peptides in large quantities. However, the umami taste value of multicopy number umami peptides is lower than the single ones, thus limiting the industrial application of recombinantly expressed umami peptides. With aims to solve this problem, modification of an umami beefy meaty peptide (BMP) with trypsin hydrolysis sites was carried out via homology modeling and molecular docking in this study. A total of 1286 modified peptide sequences were created and molecularly simulated for docking with the homology modeling-constructed umami receptor (T1R1/T1R3), and 837 peptides were found to be better docked than the BMP. Afterward, the MLSEDEGK peptide with the highest docking score was synthesized. And umami taste evaluation results demonstrated that this modified peptide was close to that of monosodium glutamate (MSG) and BMP, as confirmed by electronic tongue and sensory evaluation (umami value: 8.1 ± 0.2 for BMP; 8.2 ± 0.3 for MLSEDEGK peptide). Meanwhile, mock trypsin digestion of eight copies of MLSEDEGK peptide results showed that the introduced digestion sites were effective. Therefore, the novel modified BMP in this study has the potential for large-scale production by genetic engineering.
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Affiliation(s)
- Kunya Cheng
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, Liaoning, China
- National Engineering Research Center of Seafood, Dalian 116034, Liaoning, China
| | - Shang Wang
- School of Bioengineering, Dalian Polytechnic University, Dalian 116034, Liaoning, China
| | - Yian Wang
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, Liaoning, China
- National Engineering Research Center of Seafood, Dalian 116034, Liaoning, China
| | - Yuxiang Bao
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, Liaoning, China
- National Engineering Research Center of Seafood, Dalian 116034, Liaoning, China
| | - Pengxun Gao
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, Liaoning, China
- National Engineering Research Center of Seafood, Dalian 116034, Liaoning, China
| | - Liming Lei
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, Liaoning, China
- National Engineering Research Center of Seafood, Dalian 116034, Liaoning, China
| | - Huipeng Liang
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, Liaoning, China
- National Engineering Research Center of Seafood, Dalian 116034, Liaoning, China
| | - Sufang Zhang
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, Liaoning, China
- National Engineering Research Center of Seafood, Dalian 116034, Liaoning, China
| | - Liang Dong
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, Liaoning, China
- National Engineering Research Center of Seafood, Dalian 116034, Liaoning, China
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16
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Sanematsu K, Yamamoto M, Nagasato Y, Kawabata Y, Watanabe Y, Iwata S, Takai S, Toko K, Matsui T, Wada N, Shigemura N. Prediction of dynamic allostery for the transmembrane domain of the sweet taste receptor subunit, TAS1R3. Commun Biol 2023; 6:340. [PMID: 37012338 PMCID: PMC10070457 DOI: 10.1038/s42003-023-04705-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Accepted: 03/14/2023] [Indexed: 04/05/2023] Open
Abstract
The sweet taste receptor plays an essential role as an energy sensor by detecting carbohydrates. However, the dynamic mechanisms of receptor activation remain unclear. Here, we describe the interactions between the transmembrane domain of the G protein-coupled sweet receptor subunit, TAS1R3, and allosteric modulators. Molecular dynamics simulations reproduced species-specific sensitivity to ligands. We found that a human-specific sweetener, cyclamate, interacted with the mouse receptor as a negative allosteric modulator. Agonist-induced allostery during receptor activation was found to destabilize the intracellular part of the receptor, which potentially interfaces with the Gα subunit, through ionic lock opening. A common human variant (R757C) of the TAS1R3 exhibited a reduced response to sweet taste, in support of our predictions. Furthermore, histidine residues in the binding site acted as pH-sensitive microswitches to modulate the sensitivity to saccharin. This study provides important insights that may facilitate the prediction of dynamic activation mechanisms for other G protein-coupled receptors.
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Affiliation(s)
- Keisuke Sanematsu
- Section of Oral Neuroscience, Graduate School of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
- Oral Health/Brain Health/Total Health Research Center, Graduate School of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
- Research and Development Center for Five-Sense Devices, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan.
| | - Masato Yamamoto
- Section of Oral Neuroscience, Graduate School of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
- Department of General Dentistry, Division of Interdisciplinary Dentistry, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Yuki Nagasato
- Section of Oral Neuroscience, Graduate School of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
- Department of Bioresources and Biosciences, Faculty of Agriculture, Graduate School of Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Yuko Kawabata
- Section of Oral Neuroscience, Graduate School of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Yu Watanabe
- Section of Oral Neuroscience, Graduate School of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Shusuke Iwata
- Section of Oral Neuroscience, Graduate School of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
- Research and Development Center for Five-Sense Devices, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Shingo Takai
- Section of Oral Neuroscience, Graduate School of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Kiyoshi Toko
- Research and Development Center for Five-Sense Devices, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
- Institute for Advanced Study, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Toshiro Matsui
- Research and Development Center for Five-Sense Devices, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
- Department of Bioresources and Biosciences, Faculty of Agriculture, Graduate School of Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Naohisa Wada
- Department of General Dentistry, Division of Interdisciplinary Dentistry, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Noriatsu Shigemura
- Section of Oral Neuroscience, Graduate School of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
- Research and Development Center for Five-Sense Devices, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan.
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17
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Identification, taste characterization, and molecular docking study of a novel microbiota-derived umami peptide. Food Chem 2023; 404:134583. [DOI: 10.1016/j.foodchem.2022.134583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 08/31/2022] [Accepted: 10/09/2022] [Indexed: 11/05/2022]
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18
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Evangelista-Falcón W, Denhez C, Baena-Moncada A, Ponce-Vargas M. Revisiting the Sweet Taste Receptor T1R2-T1R3 through Molecular Dynamics Simulations Coupled with a Noncovalent Interactions Analysis. J Phys Chem B 2023; 127:1110-1119. [PMID: 36705604 DOI: 10.1021/acs.jpcb.2c07180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
It is nowadays widely accepted that sweet taste perception is elicited by the activation of the heterodimeric complex T1R2-T1R3, customarily known as sweet taste receptor (STR). However, the interplay between STR and sweeteners has not yet been fully clarified. Here through a methodology coupling molecular dynamics and the independent gradient model (igm) approach we determine the main interacting signatures of the closed (active) conformation of the T1R2 Venus flytrap domain (VFD) toward aspartame. The igm methodology provides a rapid and reliable quantification of noncovalent interactions through a score (Δginter) based on the attenuation of the electronic density gradient when two molecular fragments approach each other. Herein, this approach is coupled to a 100 ns molecular dynamics simulation (MD-igm) to explore the ligand-cavity contacts on a per-residue basis as well as a series of key inter-residue interactions that stabilize the closed form of VFD. We also apply an atomic decomposition scheme of noncovalent interactions to quantify the contribution of the ligand segments to the noncovalent interplay. Finally, a series of structural modification on aspartame are conducted in order to obtain guidelines for the rational design of novel sweeteners. Given that innovative methodologies to reliably quantify the extent of ligand-protein coupling are strongly demanded, this approach combining a noncovalent analysis and MD simulations represents a valuable contribution, that can be easily applied to other relevant biomolecular systems.
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Affiliation(s)
- Wilfredo Evangelista-Falcón
- Laboratory of Biomolecules, Faculty of Health Sciences, Universidad Peruana de Ciencias Aplicadas, Lima15023, Perú
| | - Clément Denhez
- Institut de Chimie Moléculaire de Reims UMR CNRS 7312, Université de Reims Champagne-Ardenne, Moulin de la Housse 51687, ReimsCedex 02 BP39, France
| | - Angélica Baena-Moncada
- Laboratorio de Investigación de Electroquímica Aplicada, Facultad de Ciencias de la Universidad Nacional de Ingeniería, Av. Túpac Amaru 210, Rímac, Lima31-139, Perú
| | - Miguel Ponce-Vargas
- Institut de Chimie Moléculaire de Reims UMR CNRS 7312, Université de Reims Champagne-Ardenne, Moulin de la Housse 51687, ReimsCedex 02 BP39, France
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19
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Wang C, Liu Y, Cui M, Liu B. Systematic analysis reveals novel insight into the molecular determinants of function, diversity and evolution of sweet taste receptors T1R2/T1R3 in primates. Front Mol Biosci 2023; 10:1037966. [PMID: 36762208 PMCID: PMC9905694 DOI: 10.3389/fmolb.2023.1037966] [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: 09/06/2022] [Accepted: 01/13/2023] [Indexed: 01/26/2023] Open
Abstract
Sweet taste is a primary sensation for the preference and adaption of primates to diet, which is crucial for their survival and fitness. It is clear now that the sweet perception is mediated by a G protein-coupled receptor (GPCR)-sweet taste receptor T1R2/T1R3, and many behavioral or physiological experiments have described the diverse sweet taste sensitivities in primates. However, the structure-function relationship of T1R2s/T1R3s in primates, especially the molecular basis for their species-dependent sweet taste, has not been well understood until now. In this study, we performed a comprehensive sequence, structural and functional analysis of sweet taste receptors in primates to elucidate the molecular determinants mediating their species-dependent sweet taste recognition. Our results reveal distinct taxonomic distribution and significant characteristics (interaction, coevolution and epistasis) of specific key function-related residues, which could partly account for the previously reported behavioral results of taste perception in primates. Moreover, the prosimians Lemuriformes species, which were reported to have no sensitivity to aspartame, could be proposed to be aspartame tasters based on the present analysis. Collectively, our study provides new insights and promotes a better understanding for the diversity, function and evolution of sweet taste receptors in primates.
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Affiliation(s)
- Congrui Wang
- School of Food Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, China
| | - Yi Liu
- School of Food Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, China
| | - Meng Cui
- Department of Pharmaceutical Sciences, Northeastern University, Boston, MA, United States,*Correspondence: Meng Cui, ; Bo Liu,
| | - Bo Liu
- School of Food Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, China,*Correspondence: Meng Cui, ; Bo Liu,
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20
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Utilizing the Off-Target Effects of T1R3 Antagonist Lactisole to Enhance Nitric Oxide Production in Basal Airway Epithelial Cells. Nutrients 2023; 15:nu15030517. [PMID: 36771227 PMCID: PMC9919013 DOI: 10.3390/nu15030517] [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: 12/16/2022] [Revised: 01/16/2023] [Accepted: 01/17/2023] [Indexed: 01/21/2023] Open
Abstract
Human airway sweet (T1R2 + T1R3), umami (T1R1 + T1R3), and bitter taste receptors (T2Rs) are critical components of the innate immune system, acting as sensors to monitor pathogenic growth. T2Rs detect bacterial products or bitter compounds to drive nitric oxide (NO) production in both healthy and diseased epithelial cell models. The NO enhances ciliary beating and also directly kills pathogens. Both sweet and umami receptors have been characterized to repress bitter taste receptor signaling in healthy and disease models. We hypothesized that the sweet/umami T1R3 antagonist lactisole may be used to alleviate bitter taste receptor repression in airway basal epithelial cells and enhance NO production. Here, we show that lactisole activates cAMP generation, though this occurs through a pathway independent of T1R3. This cAMP most likely signals through EPAC to increase ER Ca2+ efflux. Stimulation with denatonium benzoate, a bitter taste receptor agonist which activates largely nuclear and mitochondrial Ca2+ responses, resulted in a dramatically increased cytosolic Ca2+ response in cells treated with lactisole. This cytosolic Ca2+ signaling activated NO production in the presence of lactisole. Thus, lactisole may be useful coupled with bitter compounds as a therapeutic nasal rinse or spray to enhance beneficial antibacterial NO production in patients suffering from chronic inflammatory diseases such as chronic rhinosinusitis.
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21
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Stavrou MR, So SS, Finch AM, Ballouz S, Smith NJ. Gene expression analyses of TAS1R taste receptors relevant to the treatment of cardiometabolic disease. Chem Senses 2023; 48:bjad027. [PMID: 37539767 DOI: 10.1093/chemse/bjad027] [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: 12/15/2022] [Indexed: 08/05/2023] Open
Abstract
The sweet taste receptor (STR) is a G protein-coupled receptor (GPCR) responsible for mediating cellular responses to sweet stimuli. Early evidence suggests that elements of the STR signaling system are present beyond the tongue in metabolically active tissues, where it may act as an extraoral glucose sensor. This study aimed to delineate expression of the STR in extraoral tissues using publicly available RNA-sequencing repositories. Gene expression data was mined for all genes implicated in the structure and function of the STR, and control genes including highly expressed metabolic genes in relevant tissues, other GPCRs and effector G proteins with physiological roles in metabolism, and other GPCRs with expression exclusively outside the metabolic tissues. Since the physiological role of the STR in extraoral tissues is likely related to glucose sensing, expression was then examined in diseases related to glucose-sensing impairment such as type 2 diabetes. An aggregate co-expression network was then generated to precisely determine co-expression patterns among the STR genes in these tissues. We found that STR gene expression was negligible in human pancreatic and adipose tissues, and low in intestinal tissue. Genes encoding the STR did not show significant co-expression or connectivity with other functional genes in these tissues. In addition, STR expression was higher in mouse pancreatic and adipose tissues, and equivalent to human in intestinal tissue. Our results suggest that STR expression in mice is not representative of expression in humans, and the receptor is unlikely to be a promising extraoral target in human cardiometabolic disease.
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Affiliation(s)
- Mariah R Stavrou
- Orphan Receptor Laboratory, School of Biomedical Sciences, Faculty of Medicine and Health, UNSW Sydney, Sydney, NSW, Australia
| | - Sean Souchiart So
- Orphan Receptor Laboratory, School of Biomedical Sciences, Faculty of Medicine and Health, UNSW Sydney, Sydney, NSW, Australia
| | - Angela M Finch
- Department of Pharmacology, School of Biomedical Sciences, Faculty of Medicine and Health, UNSW Sydney, Sydney, NSW, Australia
| | - Sara Ballouz
- Garvan-Weizmann Centre for Cellular Genomics, Garvan Institute of Medical Research, Sydney, NSW, Australia
- School of Computer Science and Engineering, Faculty of Engineering, UNSW Sydney, Sydney, NSW, Australia
| | - Nicola J Smith
- Orphan Receptor Laboratory, School of Biomedical Sciences, Faculty of Medicine and Health, UNSW Sydney, Sydney, NSW, Australia
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22
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Development of hidden Markov modeling method for molecular orientations and structure estimation from high-speed atomic force microscopy time-series images. PLoS Comput Biol 2022; 18:e1010384. [PMID: 36580448 PMCID: PMC9833559 DOI: 10.1371/journal.pcbi.1010384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 01/11/2023] [Accepted: 12/20/2022] [Indexed: 12/30/2022] Open
Abstract
High-speed atomic force microscopy (HS-AFM) is a powerful technique for capturing the time-resolved behavior of biomolecules. However, structural information in HS-AFM images is limited to the surface geometry of a sample molecule. Inferring latent three-dimensional structures from the surface geometry is thus important for getting more insights into conformational dynamics of a target biomolecule. Existing methods for estimating the structures are based on the rigid-body fitting of candidate structures to each frame of HS-AFM images. Here, we extend the existing frame-by-frame rigid-body fitting analysis to multiple frames to exploit orientational correlations of a sample molecule between adjacent frames in HS-AFM data due to the interaction with the stage. In the method, we treat HS-AFM data as time-series data, and they are analyzed with the hidden Markov modeling. Using simulated HS-AFM images of the taste receptor type 1 as a test case, the proposed method shows a more robust estimation of molecular orientations than the frame-by-frame analysis. The method is applicable in integrative modeling of conformational dynamics using HS-AFM data.
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23
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Melis M, Mastinu M, Naciri LC, Muroni P, Tomassini Barbarossa I. Associations between Sweet Taste Sensitivity and Polymorphisms (SNPs) in the TAS1R2 and TAS1R3 Genes, Gender, PROP Taster Status, and Density of Fungiform Papillae in a Genetically Homogeneous Sardinian Cohort. Nutrients 2022; 14:4903. [PMID: 36432589 PMCID: PMC9696868 DOI: 10.3390/nu14224903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 11/17/2022] [Accepted: 11/18/2022] [Indexed: 11/22/2022] Open
Abstract
Individual differences in sweet taste sensitivity can affect dietary preferences as well as nutritional status. Despite the lack of consensus, it is believed that sweet taste is impacted by genetic and environmental variables. Here we determined the effect of well-established factors influencing the general taste variability, such as gender and fungiform papillae density, specific genetic variants (SNPs of TAS1R2 and TAS1R3 receptors genes), and non-specific genetic factors (PROP phenotype and genotype), on the threshold and suprathreshold sweet taste sensitivity. Suprathreshold measurements showed that the sweet taste response increased in a dose-dependent manner, and this was related to PROP phenotype, gender, rs35874116 SNP in the TAS1R2 gene, and rs307355 SNP in the TAS1R3 gene. The threshold values and density of fungiform papillae exhibited a strong correlation, and both varied according to PROP phenotype. Our data confirm the role of PROP taste status in the sweet perception related to fungiform papilla density, show a higher sweet sensitivity in females who had lower BMI than males, and demonstrate for the first time the involvement of the rs35874116 SNP of TAS1R2 in the sweet taste sensitivity of normal weight subjects with body mass index (BMI) ranging from 20.2 to 24.8 kg/m2. These results may have an important impact on nutrition and health mostly in subjects with low taste ability for sweets and thus with high vulnerability to developing obesity or metabolic disease.
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Affiliation(s)
- Melania Melis
- Department of Biomedical Sciences, University of Cagliari, 09042 Monserrato, CA, Italy
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24
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Liang Y, Yao J, Qiu R, Chen A, Huang H, Lin H, Yu L. The rs35874116 single nucleotide polymorphism increases sweet intake and the risk of severe early childhood caries: a case–control study. BMC Oral Health 2022; 22:471. [PMCID: PMC9636656 DOI: 10.1186/s12903-022-02512-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 10/18/2022] [Indexed: 11/08/2022] Open
Abstract
Abstract
Background
Dental caries is one of the most prevalent chronic diseases worldwide among children. The rs35874116 single nucleotide polymorphism (SNP) in the sweet receptor gene TAS1R2 has been associated with dental caries at a high risk in permanent teeth among school children and adults. To date, little is known about the association of this SNP with sweet intake and caries risk in the primary school children.
Methods
Total of 236 children were included, namely 118 subjects in the non-caries (NC) group and severe early childhood caries (S-ECC) group, respectively. Oral mucosa cells were collected from all the selected children, and the full length of exon 3 in TAS1R2 was sequenced to analyse rs35874116 polymorphism. A questionnaire was used to collect information about socio-demographic information, frequency of sweet intake and oral hygiene habits. Multiple logistic regression models were applied to assess the relationship of rs35874116 polymorphism with frequency of sweet intake and S-ECC among the five-year-old children.
Results
Children with the TT genotype of rs35874116 had a higher frequency of sweet intake than CT/CC carriers (51.3% vs. 32.7%; x2 = 5.436, p = 0.020), and S-ECC individuals were more likely to be TT genotype carriers than NC individuals (53.5% vs. 46.5%; x2 = 4.353, p = 0.037). Multiple logistic regression analyses showed that the TT genotype of rs35874116 was not only significantly related to the frequency of sweet intake (OR = 2.25, 95% CI = 1.14–4.44) but also significantly associated with S-ECC (OR = 2.11, 95% CI = 1.01 ~ 4.42).
Conclusions
The rs35874116 polymorphism might increase sweet intake and the risk of S-ECC among five-year-old children in Nanning, China.
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25
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Abstract
When it comes to food, one tempting substance is sugar. Although sweetness is detected by the tongue, the desire to consume sugar arises from the gut. Even when sweet taste is impaired, animals can distinguish sugars from non-nutritive sweeteners guided by sensory cues arising from the gut epithelium. Here, we review the molecular receptors, cells, circuits and behavioural consequences associated with sugar sensing in the gut. Recent work demonstrates that some duodenal cells, termed neuropod cells, can detect glucose using sodium-glucose co-transporter 1 and release glutamate onto vagal afferent neurons. Based on these and other data, we propose a model in which specific populations of vagal neurons relay these sensory cues to distinct sets of neurons in the brain, including neurons in the caudal nucleus of the solitary tract, dopaminergic reward circuits in the basal ganglia and homeostatic feeding circuits in the hypothalamus, that alter current and future sugar consumption. This emerging model highlights the critical role of the gut in sensing the chemical properties of ingested nutrients to guide appetitive decisions.
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Affiliation(s)
- Winston W Liu
- Laboratory of Gut Brain Neurobiology, Duke University, Durham, NC, USA
- Department of Medicine, Duke University, Durham, NC, USA
- Department of Neurobiology, Duke University, Durham, NC, USA
| | - Diego V Bohórquez
- Laboratory of Gut Brain Neurobiology, Duke University, Durham, NC, USA.
- Department of Medicine, Duke University, Durham, NC, USA.
- Department of Neurobiology, Duke University, Durham, NC, USA.
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26
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Deck CM, Behrens M, Wendelin M, Ley JP, Krammer GE, Lieder B. Impact of lactisole on the time-intensity profile of selected sweeteners in dependence of the binding site. Food Chem X 2022; 15:100446. [PMID: 36211761 PMCID: PMC9532755 DOI: 10.1016/j.fochx.2022.100446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 08/30/2022] [Accepted: 09/12/2022] [Indexed: 10/25/2022] Open
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27
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Identification, taste properties and molecular docking of novel umami peptides from Butyriboletus roseoflavus. Eur Food Res Technol 2022. [DOI: 10.1007/s00217-022-04061-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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28
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Laffitte A, Belloir C, Neiers F, Briand L. Functional Characterization of the Venus Flytrap Domain of the Human TAS1R2 Sweet Taste Receptor. Int J Mol Sci 2022; 23:ijms23169216. [PMID: 36012481 PMCID: PMC9409066 DOI: 10.3390/ijms23169216] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 08/09/2022] [Accepted: 08/11/2022] [Indexed: 11/16/2022] Open
Abstract
The human sweet taste receptor is a heterodimeric receptor composed of two distinct G-protein-coupled receptors (GPCRs), TAS1R2 and TAS1R3. The TAS1R2 and TAS1R3 subunits are members of a small family of class C GPCRs whose members share the same architecture, comprising a Venus Flytrap (VFT) module linked to the seven transmembrane domains (TMDs) by a short cysteine-rich region (CRR). The VFT module of TAS1R2 contains the primary binding site for most of the sweet-tasting compounds, including natural sugars and artificial and natural sweeteners. However, cellular assays, molecular docking and site-directed mutagenesis studies have revealed that the VFT, CRR and TMD of TAS1R3 interact with some sweeteners, including the sweet-tasting protein brazzein. The aim of this study was to better understand the contribution of TAS1R2-VFT in the binding of sweet stimuli. To achieve this, we heterologously expressed human TAS1R2-VFT (hTAS1R2-VFT) in Escherichia coli. Circular dichroism spectroscopic studies revealed that hTAS1R2-VFT was properly folded with evidence of secondary structures. Using size-exclusion chromatography coupled with light scattering, we found that hTAS1R2-VFT behaves as a monomer. Ligand binding quantified by intrinsic tryptophan fluorescence showed that hTAS1R2-VFT is capable of binding sweet stimuli with Kd values, in agreement with physiological detection. Furthermore, we investigated whether the impact of point mutations, already shown to have deleterious effects on cellular assays, could impact the ability of hTAS1R2-VFT to bind sweet ligands. As expected, the ligand affinities of hTAS1R2-VFT were drastically reduced through the introduction of single amino acid substitutions (D278A and E382A) known to abolish the response of the full-length TAS1R2/TAS1R3 receptor. This study demonstrates the feasibility of producing milligram quantities of hTAS1R2-VFT to further characterize the mechanism of binding interaction and perform structural studies.
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29
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Elucidation of Response Mechanism of a Potentiometric Sweetness Sensor with a Lipid/Polymer Membrane for Uncharged Sweeteners. CHEMOSENSORS 2022. [DOI: 10.3390/chemosensors10050166] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Nowadays, the utilization of a taste sensor with lipid/polymer membranes is one of the most accurate and objective ways to evaluate the tastes of solutions. However, it has been difficult to evaluate uncharged sweet substances, such as sucrose, because the conventional taste sensor uses the potentiometric measurement, which is mainly based on changes in the surface electric charge density of the membrane. Previous studies have reported that a sweetness sensor called GL1 can evaluate the sweetness of sugars and sugar alcohols, and is commercially available for food, beverage, and pharmaceutical industries. However, the response mechanism of GL1 has not been fully elucidated. In this study, we focus on clarifying the effect of concentrations and types of metal ions in the conditioning solution on the response mechanism of the sweetness sensor GL1. Moreover, according to the different concentrations and types of metal ions in conditioning solutions, the complex formation and the hydrated radius were considered to influence the membrane potential measured in a reference solution and the sensor responses. The purpose of this study is to elucidate the response mechanism and improve the selectivity and sensitivity of the sweetness sensor.
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30
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Beppu K, Tsutsumi R, Ansai S, Ochiai N, Terakawa M, Mori M, Kuroda M, Horikawa K, Tomoi T, Sakamoto J, Kamei Y, Naruse K, Sakaue H. Development of a screening system for agents that modulate taste receptor expression with the CRISPR-Cas9 system in medaka. Biochem Biophys Res Commun 2022; 601:65-72. [DOI: 10.1016/j.bbrc.2022.02.082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 02/16/2022] [Accepted: 02/21/2022] [Indexed: 11/02/2022]
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31
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Servant NB, Williams ME, Brust PF, Tang H, Wong MS, Chen Q, Lebl-Rinnova M, Adamski-Werner SL, Tachdjian C, Servant G. A Dynamic Mass Redistribution Assay for the Human Sweet Taste Receptor Uncovers G-Protein Dependent Biased Ligands. Front Pharmacol 2022; 13:832529. [PMID: 35250580 PMCID: PMC8893300 DOI: 10.3389/fphar.2022.832529] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 01/24/2022] [Indexed: 12/26/2022] Open
Abstract
The sweet taste receptor is rather unique, recognizing a diverse repertoire of natural or synthetic ligands, with a surprisingly large structural diversity, and with potencies stretching over more than six orders of magnitude. Yet, it is not clear if different cell-based assays can faithfully report the relative potencies and efficacies of these molecules. Indeed, up to now, sweet taste receptor agonists have been almost exclusively characterized using cell-based assays developed with overexpressed and promiscuous G proteins. This non-physiological coupling has allowed the quantification of receptor activity via phospholipase C activation and calcium mobilization measurements in heterologous cells on a FLIPR system, for example. Here, we developed a novel assay for the human sweet taste receptor where endogenous G proteins and signaling pathways are recruited by the activated receptor. The effects of several sweet taste receptor agonists and other types of modulators were recorded by measuring changes in dynamic mass redistribution (DMR) using an Epic® reader. Potency and efficacy values obtained in the DMR assay were compared to those results obtained with the classical FLIPR assay. Results demonstrate that for some ligands, the two assay systems provide similar information. However, a clear bias for the FLIPR assay was observed for one third of the agonists evaluated, suggesting that the use of non-physiological coupling may influence the potency and efficacy of sweet taste receptor ligands. Replacing the promiscuous G protein with a chimeric G protein containing the C-terminal tail 25 residues of the physiologically relevant G protein subunit Gαgustducin reduced or abrogated bias.
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32
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Kim TY, Woo EJ, Yoon TS. Binding mode of brazzein to the taste receptor based on crystal structure and docking simulation. Biochem Biophys Res Commun 2022; 592:119-124. [DOI: 10.1016/j.bbrc.2022.01.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Revised: 01/02/2022] [Accepted: 01/04/2022] [Indexed: 01/03/2023]
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33
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Jeong JY, Cha YK, Ahn SR, Shin J, Choi Y, Park TH, Hong S. Ultrasensitive Bioelectronic Tongue Based on the Venus Flytrap Domain of a Human Sweet Taste Receptor. ACS APPLIED MATERIALS & INTERFACES 2022; 14:2478-2487. [PMID: 34989242 DOI: 10.1021/acsami.1c17349] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Sweet taste is an important factor that regulates calorie intake and contributes to food preferences in humans and animals. Therefore, the evaluation of sweet substances is essential for various fields such as healthcare, food, and pharmaceutical industries. Sweet tastants are detected by sweet taste receptors which are class C G-protein-coupled receptors. T1R2 venus flytrap (VFT) of the sweet taste receptor is known as a primary ligand-binding domain for sweet tastants. In this study, we developed an ultrasensitive artificial sweet taste bioelectronic tongue based on the T1R2 VFT of a human sweet taste receptor. Here, the T1R2 VFT of a human sweet taste receptor was successfully overexpressed in a bacterial expression system. A T1R2 VFT-immobilized carbon nanotube field-effect transistor with floating electrodes was exploited as an artificial sweet taste sensory system. Significantly, our T1R2 VFT-functionalized bioelectronic tongue could be used to detect solutions of sweet tastants down to 0.1 fM and selectively discriminate sweet substances from other taste substances. Furthermore, our device could be used to monitor the response of the T1R2 VFT domain of a sweet taste receptor to sweet substances in real food environments such as apple juice and chamomile herb tea. Moreover, our device was used to evaluate the inhibition and enhancement effects on sweet taste receptors by zinc ions and chamomile tea, respectively. In addition, our device demonstrated long-term storability and reusability. In this respect, our sweet taste bioelectronic tongue could be a promising tool for various basic research and industrial applications.
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Affiliation(s)
- Jin-Young Jeong
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
| | - Yeon Kyung Cha
- Interdisciplinary Program in Bioengineering, Seoul National University, Seoul 08826, Korea
| | - Sae Ryun Ahn
- Industry Collaboration Center, Industry-Academic Cooperation Foundation, Sookmyung Women's University, Seoul 04310, Korea
| | - Junghyun Shin
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
| | - Yoonji Choi
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
| | - Tai Hyun Park
- Interdisciplinary Program in Bioengineering, Seoul National University, Seoul 08826, Korea
- School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul 08826, Korea
| | - Seunghun Hong
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
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34
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Rasheed H, Fiaz S, Khan MA, Mehmood S, Ullah F, Saeed S, Khan SU, Yaseen T, Hussain RM, Qayyum A. Characterization of functional genes GS3 and GW2 and their effect on the grain size of various landraces of rice (Oryza sativa). Mol Biol Rep 2022; 49:5397-5403. [PMID: 35025032 DOI: 10.1007/s11033-022-07119-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 01/04/2022] [Indexed: 11/28/2022]
Abstract
BACKGROUND Grain size is an essential factor of grain quality and yield in rice. The genetic studies have substantially contributed to enhancing yield and maintaining a good quality of rice. The two major genes GS3 (a negative regulator of grain length) and GW2 (a negative regulator of grain width) with functional mutation play a significant role in controlling the grain size of rice. METHODS AND RESULTS: In the study, 17 different widely grown Pakistani landraces of various genetic and geographic backgrounds were evaluated for grain phenotypic traits (1000-grain weight, length, width, and thickness) and also screened for genotypic mutation in GS3 and GW2 genes. Phenotypic data revealed the range for grain weight from 16.86 g (Lateefy) to 26.91 g (PS2), grain length ranged from 7.27 mm (JP-5) to 12.18 mm (PS2), grain width ranged from 2.01 mm (Lateefy) to 3.51 mm (JP5), and grain thickness ranged from 1.79 mm to 2.19. Correlation revealed a negative and significant correlation between grain width and length. There was no significant correlation between grain length and 1000-grain weight and grain width. LSD test displayed that the means of three variables grain length, grain width, and 1000-grain weight were statistically different from one another except grain width and grain breadth. Fifteen accessions carried the domesticated allele of GS3 while JP5 and Fakhr-e-Malakand carried the dominant allele. Similarly, fifteen accessions carried the dominant allele of GW2 while JP-5 and Fakhr-e-Malakand carried the mutant allele. CONCLUSIONS The study shows that the mutant alleles of both genes are of significance to pyramid them in any breeding program. However, just incorporating favorable alleles is not the sole solution for improving the grain size. Therefore, further elucidation of GS3 and GW2 genes regulatory network, their interaction, trade-off, and pathways will better coordinate their marker-assisted selection in the future breeding program. Additionally, the study concluded that the selection of grain size was not dependent on 1000-grain weight in the selected germplasm.
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Affiliation(s)
- Haroon Rasheed
- Department of Botany, University of Science and Technology, Bannu, KPK, Pakistan.,Institute of Nuclear Agricultural Sciences College of Agriculture and Biotechnology, Zhejiang University, Zijingang Campus, Hangzhou, People's Republic of China
| | - Sajid Fiaz
- Department of Plant Breeding and Genetics, The University of Haripur, Haripur, 22620, Pakistan.
| | - Muhammad Abid Khan
- Department of Botany, University of Science and Technology, Bannu, KPK, Pakistan.,Department of Botany, Ghazi University, Dera Ghazi Khan, Pakistan
| | - Sultan Mehmood
- Department of Botany, University of Science and Technology, Bannu, KPK, Pakistan
| | - Faizan Ullah
- Department of Botany, University of Science and Technology, Bannu, KPK, Pakistan
| | - Sumbul Saeed
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Shahid Ullah Khan
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.
| | - Tabassam Yaseen
- Department of Botany, Bacha khan University, Charsadda, Pakistan
| | - Reem M Hussain
- State Key Laboratory of Agricultural Microbiology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.,Faculty of Agriculture, Crop Field Department, Tishreen University, Lattakia, Syria
| | - Abdul Qayyum
- Department of Agronomy, The University of Haripur, Haripur, 22620, Pakistan
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35
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Palmer RK. Why Taste Is Pharmacology. Handb Exp Pharmacol 2022; 275:1-31. [PMID: 35461405 DOI: 10.1007/164_2022_589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The chapter presents an argument supporting the view that taste, defined as the receptor-mediated signaling of taste cells and consequent sensory events, is proper subject matter for the field of pharmacology. The argument develops through a consideration of how the field of pharmacology itself is to be defined. Though its application toward the discovery and development of therapeutics is of obvious value, pharmacology nevertheless is a basic science committed to examining biological phenomena controlled by the selective interactions between chemicals - regardless of their sources or uses - and receptors. The basic science of pharmacology is founded on the theory of receptor occupancy, detailed here in the context of taste. The discussion then will turn to consideration of the measurement of human taste and how well the results agree with the predictions of receptor theory.
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36
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Zheng X, Zhu J, Liu J, Wang H, Qin Y, Jiang P, Xiao L, Gong T, Li Y, Peng X, Xu X, Cheng L, Huang L, Chen Q, Zhou X, Margolskee RF. Sweet taste perception in mice is blunted by PTBP1-regulated skipping of Tas1r2 exon 4. Chem Senses 2022; 47:6884719. [PMID: 36484118 DOI: 10.1093/chemse/bjac034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Taste perception, initiated by activation of taste receptors in taste bud cells, is crucial for regulating nutrient intake. Genetic polymorphisms in taste receptor genes cannot fully explain the wide individual variations of taste sensitivity. Alternative splicing (AS) is a ubiquitous posttranscriptional mode of gene regulation that enriches the functional diversity of proteins. Here, we report the identification of a novel splicing variant of sweet taste receptor gene Tas1r2 (Tas1r2_∆e4) in mouse taste buds and the mechanism by which it diminishes sweet taste responses in vitro and in vivo. Skipping of Tas1r2 exon 4 in Tas1r2_∆e4 led to loss of amino acids in the extracellular Venus flytrap domain, and the truncated isoform reduced the response of sweet taste receptors (STRs) to all sweet compounds tested by generating nonfunctional T1R2/T1R3 STR heterodimers. The splicing factor PTBP1 (polypyrimidine tract-binding protein 1) promoted Tas1r2_∆e4 generation through binding to a polypyrimidine-rich splicing silencer in Tas1r2 exon 4, thus decreasing STR function and sweet taste perception in mice. Taken together, these data reveal the existence of a regulated AS event in Tas1r2 expression and its effect on sweet taste perception, providing a novel mechanism for modulating taste sensitivity at the posttranscriptional level.
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Affiliation(s)
- Xin Zheng
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, P. R. China
| | - Jianhui Zhu
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Hangzhou 310006, P. R. China
| | - Jiaxin Liu
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, P. R. China
| | - Hong Wang
- Monell Chemical Senses Center, Philadelphia, PA 19104, USA
| | - Yumei Qin
- School of Food Science and Bioengineering, Zhejiang Gongshang University, Hangzhou 310006, P. R. China
| | - Peihua Jiang
- Monell Chemical Senses Center, Philadelphia, PA 19104, USA
| | - Li Xiao
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, P. R. China
| | - Tao Gong
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, P. R. China
| | - Yuqing Li
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, P. R. China
| | - Xian Peng
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, P. R. China
| | - Xin Xu
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, P. R. China
| | - Lei Cheng
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, P. R. China
| | - Liquan Huang
- College of Life Sciences, Zhejiang University, Hangzhou 310058, P. R. China
| | - Qianming Chen
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Hangzhou 310006, P. R. China
| | - Xuedong Zhou
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, P. R. China
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37
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Zhao X, Liu M, Cui M, Liu B. Multiple interaction modes between saccharin and sweet taste receptors determine a species-dependent response to saccharin. FEBS Open Bio 2021; 12:494-499. [PMID: 34932896 PMCID: PMC8804617 DOI: 10.1002/2211-5463.13355] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 11/03/2021] [Accepted: 12/20/2021] [Indexed: 11/05/2022] Open
Abstract
Saccharin is a commonly used artificial sweetener that exhibits both sweetening and sweet inhibition activities. The species-dependent response towards saccharin and the interaction between saccharin and the sweet taste receptor T1R2/T1R3 remain elusive. In this study we used mismatched chimeras of T1R2 and T1R3 and calcium mobilization functional analysis to reveal a detailed species-dependent response towards saccharin of human, squirrel monkey, and mouse sweet taste receptors. Our findings, combined with previous results by others, suggest multiple and complex interaction modes between saccharin and the sweet taste receptor, which are helpful guidelines for effective modulation of the sweet taste by sweetener/sweet inhibitors.
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Affiliation(s)
- Xiangzhong Zhao
- Department of Food Science and Engineering, Qilu University of Technology, Jinan, China
| | - Meng Liu
- Department of Food Science and Engineering, Qilu University of Technology, Jinan, China
| | - Meng Cui
- Department of Pharmaceutical Sciences, Northeastern University, Boston, MA, USA
| | - Bo Liu
- Department of Food Science and Engineering, Qilu University of Technology, Jinan, China
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Jensterle M, DeVries JH, Battelino T, Battelino S, Yildiz B, Janez A. Glucagon-like peptide-1, a matter of taste? Rev Endocr Metab Disord 2021; 22:763-775. [PMID: 33123893 DOI: 10.1007/s11154-020-09609-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/26/2020] [Indexed: 01/22/2023]
Abstract
Understanding of gustatory coding helps to predict, and perhaps even modulate the ingestive decision circuitry, especially when eating behaviour becomes dysfunctional. Preclinical research demonstrated that glucagon like peptide 1 (GLP-1) is locally synthesized in taste bud cells in the tongue and that GLP-1 receptor exists on the gustatory nerves in close proximity to GLP-1 containing taste bud cells. In humans, the tongue has not yet been addressed as clinically relevant target for GLP-1 based therapies. The primary aim of the current review was to elaborate on the role of GLP- 1 in mammalian gustatory system, in particular in the perception of sweet. Secondly, we aimed to explore what modulates gustatory coding and whether the GLP-1 based therapies might be involved in regulation of taste perception. We performed a series of PubMed, Medline and Embase databases systemic searches. The Population-Intervention-Comparison-Outcome (PICO) framework was used to identify interventional studies. Based on the available data, GLP-1 is specifically involved in the perception of sweet. Aging, diabetes and obesity are characterized by diminished taste and sweet perception. Calorie restriction and bariatric surgery are associated with a diminished appreciation of sweet food. GLP-1 receptor agonists (RAs) modulate food preference, yet its modulatory potential in gustatory coding is currently unknown. Future studies should explore whether GLP-1 RAs modulate taste perception to the extent that changes of food preference and consumption ensue.
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Affiliation(s)
- Mojca Jensterle
- Division of Internal Medicine, Department of Endocrinology, Diabetes and Metabolic Diseases, University Medical Centre Ljubljana, Zaloška cesta, 7, 1000, Ljubljana, Slovenia
- Department of Internal Medicine, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia, Zaloška cesta 7, 1000, Ljubljana, Slovenia
| | - J Hans DeVries
- Department of Endocrinology and Metabolism, Amsterdam University Medical Center, University of Amsterdam, Meibergdreef 9, 1105, AZ, Amsterdam, The Netherlands
| | - Tadej Battelino
- Department of Endocrinology, Diabetes and Metabolism, University Children's Hospital, University Medical Centre Ljubljana, Bohoričeva 20, SI-1000, Ljubljana, Slovenia
- Department of Pediatrics, Faculty of Medicine, University of Ljubljana, Bohoričeva 20, SI-1000, Ljubljana, Slovenia
| | - Saba Battelino
- Department of Otorhinolaryngology and Cervicofacial Surgery, University Medical Centre Ljubljana, Zaloska cesta 2, 1000, Ljubljana, Slovenia
- Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Bulent Yildiz
- Department of Internal Medicine, Division of Endocrinology and Metabolism, Hacettepe University School of Medicine, Hacettepe, 06100, Ankara, Turkey
| | - Andrej Janez
- Division of Internal Medicine, Department of Endocrinology, Diabetes and Metabolic Diseases, University Medical Centre Ljubljana, Zaloška cesta, 7, 1000, Ljubljana, Slovenia.
- Department of Internal Medicine, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia, Zaloška cesta 7, 1000, Ljubljana, Slovenia.
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Biophysical and functional characterization of the human TAS1R2 sweet taste receptor overexpressed in a HEK293S inducible cell line. Sci Rep 2021; 11:22238. [PMID: 34782704 PMCID: PMC8593021 DOI: 10.1038/s41598-021-01731-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 11/01/2021] [Indexed: 01/02/2023] Open
Abstract
Sweet taste perception is mediated by a heterodimeric receptor formed by the assembly of the TAS1R2 and TAS1R3 subunits. TAS1R2 and TAS1R3 are class C G-protein-coupled receptors whose members share a common topology, including a large extracellular N-terminal domain (NTD) linked to a seven transmembrane domain (TMD) by a cysteine-rich domain. TAS1R2-NTD contains the primary binding site for sweet compounds, including natural sugars and high-potency sweeteners, whereas the TAS1R2-TMD has been shown to bind a limited number of sweet tasting compounds. To understand the molecular mechanisms governing receptor–ligand interactions, we overexpressed the human TAS1R2 (hTAS1R2) in a stable tetracycline-inducible HEK293S cell line and purified the detergent-solubilized receptor. Circular dichroism spectroscopic studies revealed that hTAS1R2 was properly folded with evidence of secondary structures. Using size exclusion chromatography coupled to light scattering, we found that the hTAS1R2 subunit is a dimer. Ligand binding properties were quantified by intrinsic tryptophan fluorescence. Due to technical limitations, natural sugars have not been tested. However, we showed that hTAS1R2 is capable of binding high potency sweeteners with Kd values that are in agreement with physiological detection. This study offers a new experimental strategy to identify new sweeteners or taste modulators that act on the hTAS1R2 and is a prerequisite for structural query and biophysical studies.
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Beppu K, Shono H, Kawakami A, Takashi T, Watanabe S, Yoshida A, Kuroda M, Fujimoto C, Kanamura R, Ohnishi H, Kondo E, Azuma T, Sato G, Kitamura Y, Tsutsumi R, Sakaue H, Takeda N. Dietary supplementation with monosodium glutamate with dietary balance such as protein, salt and sugar intake with increasing T1R3 taste receptor gene expression in healthy females. THE JOURNAL OF MEDICAL INVESTIGATION 2021; 68:315-320. [PMID: 34759151 DOI: 10.2152/jmi.68.315] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
We previously showed that chemotherapy-induced dysgeusia was associated with lingual taste receptor gene expression, and monosodium glutamate (MSG) improved dysgeusia by upregulating taste 1 receptor 3(T1R3) gene expression. In recent years, decreased taste sensitivity has also been reported in some young people, and these are partly due to their disordered eating habits. From these background, we investigated the effects of MSG supplementation on taste receptor expression and dietary intake in healthy females. Fifteen young healthy volunteers were enrolled for the present crossover study and divided in two groups (dietary supplementation with MSG at 2.7 g / day or 0.27 g / day). The relative expression of T1R3, a subunit of both umami and sweet taste receptors, in the tongue was assessed by quantitative PCR analysis. Food intake was assessed by food frequency questionnaire (FFQg), and body composition was measured using Omron HBF-701. T1R3 expression levels in the tongue and taste sensitivity increased significantly in participants who consumed <10 g of MSG daily, whereas no alteration was observed in participants who consumed >10 g of MSG daily. Furthermore, protein, fat, and carbohydrate (PFC) balance and salt and sugar intake improved by MSG supplementation. In conclusion, MSG supplementation increased T1R3 expression in the tongue and improved dietary balance. J. Med. Invest. 68 : 315-320, August, 2021.
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Affiliation(s)
- Kana Beppu
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan.,These authors contributed equally to this work
| | - Hitoshi Shono
- Department of Otolaryngology, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan.,These authors contributed equally to this work
| | - Ayuka Kawakami
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Tomoe Takashi
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Suzuno Watanabe
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Akari Yoshida
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Masashi Kuroda
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Chisa Fujimoto
- Department of Otolaryngology, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Ryo Kanamura
- Department of Otolaryngology, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Hiroki Ohnishi
- Department of Otolaryngology, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Eiji Kondo
- Department of Otolaryngology, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Takahito Azuma
- Department of Otolaryngology, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Go Sato
- Department of Otolaryngology, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Yoshiaki Kitamura
- Department of Otolaryngology, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Rie Tsutsumi
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Hiroshi Sakaue
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Noriaki Takeda
- Department of Otolaryngology, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan
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41
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Jang J, Kim SK, Guthrie B, Goddard WA. Synergic Effects in the Activation of the Sweet Receptor GPCR Heterodimer for Various Sweeteners Predicted Using Molecular Metadynamics Simulations. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:12250-12261. [PMID: 34613740 DOI: 10.1021/acs.jafc.1c03779] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The sweet taste is elicited by activation of the TAS1R2/1R3 heterodimer G protein-coupled receptor. This is a therapeutic target for treatment of obesity and metabolic dysfunctions. Sweetener blends provide attractive strategies to lower the sugar level while preserving the attractive taste of food. To understand the synergic effect of various sweetener blend combinations of artificial and natural sweeteners, we carried out our molecular dynamics studies using predicted structures of the TAS1R2/1R3 heterodimer and predicted structures for the sweeteners. We used as a measure of activation the intracellular ionic lock distance between transmembrane helices 3 and 6 of TAS1R3. We find that full synergic combinations [rebaudioside A (Reb-A)/acesulfame K and Reb-A/sucralose] and partial synergic combinations (sucralose/acesulfame K) show significantly more negative changes in the free energy compared to single-ligand cases, while a pair known to be suppressive (saccharin and acesulfame K) shows significantly less changes than for the single-ligand case. This study provides an atomistic understanding of the mechanism for synergy and identifies new combinations of sweeteners to reduce the caloric content for treating diseases.
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Affiliation(s)
- Jaewan Jang
- Materials and Process Simulation Center (139-74), California Institute of Technology, Pasadena, California 91125, United States
| | - Soo-Kyung Kim
- Materials and Process Simulation Center (139-74), California Institute of Technology, Pasadena, California 91125, United States
| | - Brian Guthrie
- Cargill Global Core Research, Wayzata, Minnesota 55391, United States
| | - William A Goddard
- Materials and Process Simulation Center (139-74), California Institute of Technology, Pasadena, California 91125, United States
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42
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On the human taste perception: Molecular-level understanding empowered by computational methods. Trends Food Sci Technol 2021. [DOI: 10.1016/j.tifs.2021.07.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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43
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Aida H, Morita R, Shigeta Y, Harada R. In silico mutational analyses reveal different ligand-binding abilities of double pockets of medaka fish taste receptor type 1 essential for efficient taste recognition. Phys Chem Chem Phys 2021; 23:20398-20405. [PMID: 34494045 DOI: 10.1039/d1cp02876f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Taste receptors are important sensors for the detection of nutrient concentrations in animals. Tastes are recognized by interactions between chemical substances and taste receptors. Recently, the high-resolution X-ray crystal structure of the extracellular ligand-binding domains (LBDs) of medaka fish (Oryzias latipes) taste receptor type 1 (T1r) complexed with ligands (amino acids) was determined. Medaka fish T1r is a heterodimer composed of two different LBDs, T1r2aLBD and T1r3LBD. In this study, we performed all-atom molecular dynamics (MD) simulations on this heterodimer (T1r2aLBD-T1r3LBD) to address mutational effects on key residues near each ligand-binding pocket in recognizing one of the ligands (L-Gln). For T1r2aLBD, Ser165 is important in ligand recognition due to its direct hydrogen bonding with the ligand. After mutating Ser165 to Ile or Ala, the direct hydrogen bonds between the ligand and the binding pocket were weakened, which destabilized the ligand-binding form of T1r2aLBD. For T1r3LBD, Ser300 is important in ligand recognition. The water-mediated hydrogen bond with the side-chain hydroxyl group of Ser300 is a single interaction that maintains the ligand-binding form of T1r3LBD. After mutating Ser300 to Glu or Ala, both mutant systems almost maintained their ligand-binding form. As a mechanism for maintaining the binding form of T1r3LBD, alternative hydrogen bonds were formed as direct interactions instead of the indirect water-mediated interactions found in the wild-type system, which stabilized the binding form of T1r3LBD. Judging from our in silico mutational analyses, T1r2aLBD was structurally destabilized by the amino acid mutations. Therefore, it might be required that the ligand-binding pocket of T1r2aLBD is composed of a set of specific residues to maintain its ligand-binding form. On the contrary, T1r3LBD was robust enough to withstand the amino acid mutations. These different ligand-binding abilities of both LBDs provide multiple binding modes, which might be helpful for discriminating various taste substances or detecting concentrations of nutrients efficiently.
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Affiliation(s)
- Hayato Aida
- Master's Program in Biology, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan.
| | - Rikuri Morita
- Center for Computational Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan
| | - Yasuteru Shigeta
- Master's Program in Biology, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan. .,Center for Computational Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan
| | - Ryuhei Harada
- Master's Program in Biology, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan. .,Center for Computational Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan
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44
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Shono H, Tsutsumi R, Beppu K, Matsushima R, Watanabe S, Fujimoto C, Kanamura R, Ohnishi H, Kondo E, Azuma T, Sato G, Kawai M, Matsumoto H, Kitamura Y, Sakaue H, Takeda N. Dietary Supplementation with Monosodium Glutamate Suppresses Chemotherapy-Induced Downregulation of the T1R3 Taste Receptor Subunit in Head and Neck Cancer Patients. Nutrients 2021; 13:2921. [PMID: 34578798 PMCID: PMC8469378 DOI: 10.3390/nu13092921] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 08/04/2021] [Accepted: 08/17/2021] [Indexed: 01/17/2023] Open
Abstract
(Background) We investigated the effect of dietary supplementation with monosodium glutamate (MSG) on chemotherapy-induced downregulation of the T1R3 taste receptor subunit expression in the tongue of patients with advanced head and neck cancer. (Methods) Patients undergoing two rounds of chemoradiotherapy were randomly allocated to a control or intervention group (dietary supplementation with MSG at 2.7 g/day during the second round of chemotherapy). The relative expression of T1R3, a subunit of both umami and sweet taste receptors, in the tongue was assessed by quantitative polymerase chain reaction analysis. Dysgeusia was assessed with a visual analog scale and daily energy intake was evaluated. (Results) T1R3 expression levels in the tongue, taste sensitivity, and daily energy intake were significantly reduced after the first round of chemotherapy compared with before treatment. Furthermore, these parameters significantly decreased after the second round of chemotherapy, but the extent of decrease was significantly attenuated in the MSG group compared with the control group. (Conclusions) MSG supplementation suppresses chemotherapy-induced dysgeusia, possibly due to the inhibition of the T1R3-containing taste receptor downregulation in the tongue, thereby increasing energy intake in patients with advanced head and neck cancer.
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Affiliation(s)
- Hitoshi Shono
- Department of Otolaryngology, Institute of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan; (H.S.); (C.F.); (R.K.); (H.O.); (E.K.); (T.A.); (G.S.); (Y.K.); (N.T.)
| | - Rie Tsutsumi
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan; (K.B.); (R.M.); (S.W.); (H.S.)
| | - Kana Beppu
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan; (K.B.); (R.M.); (S.W.); (H.S.)
| | - Rina Matsushima
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan; (K.B.); (R.M.); (S.W.); (H.S.)
| | - Suzuno Watanabe
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan; (K.B.); (R.M.); (S.W.); (H.S.)
| | - Chisa Fujimoto
- Department of Otolaryngology, Institute of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan; (H.S.); (C.F.); (R.K.); (H.O.); (E.K.); (T.A.); (G.S.); (Y.K.); (N.T.)
| | - Ryo Kanamura
- Department of Otolaryngology, Institute of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan; (H.S.); (C.F.); (R.K.); (H.O.); (E.K.); (T.A.); (G.S.); (Y.K.); (N.T.)
| | - Hiroki Ohnishi
- Department of Otolaryngology, Institute of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan; (H.S.); (C.F.); (R.K.); (H.O.); (E.K.); (T.A.); (G.S.); (Y.K.); (N.T.)
| | - Eiji Kondo
- Department of Otolaryngology, Institute of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan; (H.S.); (C.F.); (R.K.); (H.O.); (E.K.); (T.A.); (G.S.); (Y.K.); (N.T.)
| | - Takahiro Azuma
- Department of Otolaryngology, Institute of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan; (H.S.); (C.F.); (R.K.); (H.O.); (E.K.); (T.A.); (G.S.); (Y.K.); (N.T.)
| | - Go Sato
- Department of Otolaryngology, Institute of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan; (H.S.); (C.F.); (R.K.); (H.O.); (E.K.); (T.A.); (G.S.); (Y.K.); (N.T.)
| | - Misako Kawai
- Frontier Research Laboratories, Institute for Innovation, Ajinomoto Co. Inc., Kawasaki 210-8681, Japan; (M.K.); (H.M.)
| | - Hideki Matsumoto
- Frontier Research Laboratories, Institute for Innovation, Ajinomoto Co. Inc., Kawasaki 210-8681, Japan; (M.K.); (H.M.)
| | - Yoshiaki Kitamura
- Department of Otolaryngology, Institute of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan; (H.S.); (C.F.); (R.K.); (H.O.); (E.K.); (T.A.); (G.S.); (Y.K.); (N.T.)
| | - Hiroshi Sakaue
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan; (K.B.); (R.M.); (S.W.); (H.S.)
| | - Noriaki Takeda
- Department of Otolaryngology, Institute of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan; (H.S.); (C.F.); (R.K.); (H.O.); (E.K.); (T.A.); (G.S.); (Y.K.); (N.T.)
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45
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Jia M, Zhang H, Xu J, Su Y, Zhu W. Feeding frequency affects the growth performance, nutrient digestion and absorption of growing pigs with the same daily feed intake. Livest Sci 2021. [DOI: 10.1016/j.livsci.2021.104558] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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46
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Choi Y, Manthey JA, Park TH, Cha YK, Kim Y, Kim Y. Correlation between in vitro binding activity of sweeteners to cloned human sweet taste receptor and sensory evaluation. Food Sci Biotechnol 2021; 30:675-682. [PMID: 34123464 DOI: 10.1007/s10068-021-00905-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 02/26/2021] [Accepted: 03/09/2021] [Indexed: 11/28/2022] Open
Abstract
The human sweet taste receptor is a TAS1R2/TAS1R3 heterodimer. To investigate the correlation between the in vitro affinity of sweeteners with stably expressed human sweet taste receptor in HEK-293 cells and human sensory evaluation, the receptor-ligand activity of bulk (sucrose, D-fructose, and allulose) and high-intensity sweeteners (saccharin, rebaudioside A, rebaudioside M, and neohesperidin dihydrochalcone) was compared by analyzing the Ca2+ release. The relative potency of the sweeteners was identified over a wide concentration range for EC50s. Relative to sucrose, bulk sweeteners showed similar concentration ranges and potency, whereas high-intensity sweeteners exhibited lower concentration ranges and higher potency. The log of the calculated EC50 of each sweetener relative to sucrose by the in vitro affinity assay was positively correlated (r = 0.9943) with the molar relative sweetness reported in the previous literatures. These results suggested a good correlation between the in vitro activity assay of sweeteners and human sensory evaluation.
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Affiliation(s)
- Yoonha Choi
- Department of Nutritional Science and Food Management, Ewha Womans University, Seoul, 03760 Republic of Korea
| | - John A Manthey
- Agricultural Research Service, U.S. Horticultural Research Lab, U. S. Dept. of Agriculture, 2001 South Rock Road, Fort Pierce, FL34945 USA
| | - Tai Hyun Park
- Interdisciplinary Program for Bioengineering, Seoul National University, Seoul, 08826 Republic of Korea.,School of Chemical and Biological Engineering, and Institute of Chemical Processes, Seoul National University, Seoul, 08826 Republic of Korea
| | - Yeon Kyung Cha
- Interdisciplinary Program for Bioengineering, Seoul National University, Seoul, 08826 Republic of Korea
| | - Yang Kim
- Center for Food & Bioconvergence, Seoul National University, Seoul, 08826 Republic of Korea
| | - Yuri Kim
- Department of Nutritional Science and Food Management, Ewha Womans University, Seoul, 03760 Republic of Korea
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47
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Rhyu MR, Lyall V. Interaction of taste-active nutrients with taste receptors. CURRENT OPINION IN PHYSIOLOGY 2021. [DOI: 10.1016/j.cophys.2020.12.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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48
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Puri S, Lee Y. Salt Sensation and Regulation. Metabolites 2021; 11:metabo11030175. [PMID: 33802977 PMCID: PMC8002656 DOI: 10.3390/metabo11030175] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 03/08/2021] [Accepted: 03/15/2021] [Indexed: 12/02/2022] Open
Abstract
Taste sensation and regulation are highly conserved in insects and mammals. Research conducted over recent decades has yielded major advances in our understanding of the molecular mechanisms underlying the taste sensors for a variety of taste sensations and the processes underlying regulation of ingestion depending on our internal state. Salt (NaCl) is an essential ingested nutrient. The regulation of internal sodium concentrations for physiological processes, including neuronal activity, fluid volume, acid–base balance, and muscle contraction, are extremely important issues in animal health. Both mammals and flies detect low and high NaCl concentrations as attractive and aversive tastants, respectively. These attractive or aversive behaviors can be modulated by the internal nutrient state. However, the differential encoding of the tastes underlying low and high salt concentrations in the brain remain unclear. In this review, we discuss the current view of taste sensation and modulation in the brain with an emphasis on recent advances in this field. This work presents new questions that include but are not limited to, “How do the fly’s neuronal circuits process this complex salt code?” and “Why do high concentrations of salt induce a negative valence only when the need for salt is low?” A better understanding of regulation of salt homeostasis could improve our understanding of why our brains enjoy salty food so much.
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Affiliation(s)
- Sonali Puri
- Interdisciplinary Program for Bio-Health Convergence, Kookmin University, Seoul 02707, Korea;
| | - Youngseok Lee
- Interdisciplinary Program for Bio-Health Convergence, Kookmin University, Seoul 02707, Korea;
- Department of Bio and Fermentation Convergence Technology, Kookmin University, Seoul 02707, Korea
- Correspondence: ; Tel.: +82-2-910-5734
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49
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Smith NJ, Grant JN, Moon JI, So SS, Finch AM. Critically evaluating sweet taste receptor expression and signaling through a molecular pharmacology lens. FEBS J 2021; 288:2660-2672. [DOI: 10.1111/febs.15768] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 02/04/2021] [Accepted: 02/15/2021] [Indexed: 12/26/2022]
Affiliation(s)
- Nicola J. Smith
- Orphan Receptor Laboratory School of Medical Sciences UNSW Sydney Kensington Australia
| | - Jennifer N. Grant
- Orphan Receptor Laboratory School of Medical Sciences UNSW Sydney Kensington Australia
- G Protein‐Coupled Receptor Laboratory School of Medical Sciences UNSW Sydney Kensington Australia
| | - Justin I. Moon
- Orphan Receptor Laboratory School of Medical Sciences UNSW Sydney Kensington Australia
- G Protein‐Coupled Receptor Laboratory School of Medical Sciences UNSW Sydney Kensington Australia
| | - Sean S. So
- Orphan Receptor Laboratory School of Medical Sciences UNSW Sydney Kensington Australia
| | - Angela M. Finch
- G Protein‐Coupled Receptor Laboratory School of Medical Sciences UNSW Sydney Kensington Australia
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50
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Behrens M. Pharmacology of TAS1R2/TAS1R3 Receptors and Sweet Taste. Handb Exp Pharmacol 2021; 275:155-175. [PMID: 33582884 DOI: 10.1007/164_2021_438] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The detection of energy-rich sweet food items has been important for our survival during evolution, however, in light of the changing lifestyles in industrialized and developing countries our natural sweet preference is causing considerable problems. Hence, it is even more important to understand how our sense of sweetness works, and perhaps even, how we may deceive it for our own benefit. This chapter summarizes current knowledge about sweet tastants and sweet taste modulators on the compound side as well as insights into the structure and function of the sweet taste receptor and the transduction of sweet signals. Moreover, methods to assess the activity of sweet substances in vivo and in vitro are compared and discussed.
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Affiliation(s)
- Maik Behrens
- Leibniz-Institute for Food Systems Biology at the Technical University of Munich, Freising, Germany.
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