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Niu B, Liu L, Gao Q, Zhu M, Chen L, Peng X, Qin B, Zhou X, Li F. Genetic mutation of Tas2r104/Tas2r105/Tas2r114 cluster leads to a loss of taste perception to denatonium benzoate and cucurbitacin B. Animal Model Exp Med 2024; 7:324-336. [PMID: 38155461 PMCID: PMC11228091 DOI: 10.1002/ame2.12357] [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: 08/22/2023] [Accepted: 09/18/2023] [Indexed: 12/30/2023] Open
Abstract
BACKGROUND Bitter taste receptors (Tas2rs) are generally considered to sense various bitter compounds to escape the intake of toxic substances. Bitter taste receptors have been found to widely express in extraoral tissues and have important physiological functions outside the gustatory system in vivo. METHODS To investigate the physiological functions of the bitter taste receptor cluster Tas2r106/Tas2r104/Tas2r105/Tas2r114 in lingual and extraoral tissues, multiple Tas2rs mutant mice and Gnat3 were produced using CRISPR/Cas9 gene-editing technique. A mixture containing Cas9 and sgRNA mRNAs for Tas2rs and Gnat3 gene was microinjected into the cytoplasm of the zygotes. Then, T7EN1 assays and sequencing were used to screen genetic mutation at the target sites in founder mice. Quantitative real-time polymerase chain reaction (qRT-PCR) and immunostaining were used to study the expression level of taste signaling cascade and bitter taste receptor in taste buds. Perception to taste substance was also studied using two-bottle preference tests. RESULTS We successfully produced several Tas2rs and Gnat3 mutant mice using the CRISPR/Cas9 technique. Immunostaining results showed that the expression of GNAT3 and PLCB2 was not altered in Tas2rs mutant mice. But qRT-PCR results revealed the changed expression profile of mTas2rs gene in taste buds of these mutant mice. With two-bottle preference tests, these mutant mice eliminate responses to cycloheximide due to genetic mutation of Tas2r105. In addition, these mutant mice showed a loss of taste perception to quinine dihydrochloride, denatonium benzoate, and cucurbitacin B (CuB). Gnat3-mediated taste receptor and its signal pathway contribute to CuB perception. CONCLUSIONS These findings implied that these mutant mice would be a valuable means to understand the biological functions of TAS2Rs in extraoral tissues and investigate bitter compound-induced responses mediated by these TAS2Rs in many extraoral tissues.
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Affiliation(s)
- Bowen Niu
- Department of Laboratory Animal Science, Shanghai Public Health Clinical CenterFudan UniversityShanghaiChina
| | - Lingling Liu
- Department of Laboratory Animal Science, Shanghai Public Health Clinical CenterFudan UniversityShanghaiChina
| | - Qian Gao
- Department of Biology, College of Life SciencesShanghai Normal UniversityShanghaiPeople's Republic of China
| | - Meng‐Min Zhu
- Department of Laboratory Animal Science, Shanghai Public Health Clinical CenterFudan UniversityShanghaiChina
| | - Lixiang Chen
- Department of Laboratory Animal Science, Shanghai Public Health Clinical CenterFudan UniversityShanghaiChina
| | - Xiu‐Hua Peng
- Department of Laboratory Animal Science, Shanghai Public Health Clinical CenterFudan UniversityShanghaiChina
| | - Boying Qin
- Department of Laboratory Animal Science, Shanghai Public Health Clinical CenterFudan UniversityShanghaiChina
| | - Xiaohui Zhou
- Department of Laboratory Animal Science, Shanghai Public Health Clinical CenterFudan UniversityShanghaiChina
| | - Feng Li
- Department of Laboratory Animal Science, Shanghai Public Health Clinical CenterFudan UniversityShanghaiChina
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Morini G. The taste for health: the role of taste receptors and their ligands in the complex food/health relationship. Front Nutr 2024; 11:1396393. [PMID: 38873558 PMCID: PMC11169839 DOI: 10.3389/fnut.2024.1396393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Accepted: 05/03/2024] [Indexed: 06/15/2024] Open
Abstract
Taste, food, and health are terms that have since always accompanied the act of eating, but the association was simple: taste serves to classify a food as good or bad and therefore influences food choices, which determine the nutritional status and therefore health. The identification of taste receptors, particularly, the G protein-coupled receptors that mediate sweet, umami, and bitter tastes, in the gastrointestinal tract has assigned them much more relevant tasks, from nutrient sensing and hormone release to microbiota composition and immune response and finally to a rationale for the gut-brain axis. Particularly interesting are bitter taste receptors since most of the times they do not mediate macronutrients (energy). The relevant roles of bitter taste receptors in the gut indicate that they could become new drug targets and their ligands new medications or components in nutraceutical formulations. Traditional knowledge from different cultures reported that bitterness intensity was an indicator for distinguishing plants used as food from those used as medicine, and many non-cultivated plants were used to control glucose level and treat diabetes, modulate hunger, and heal gastrointestinal disorders caused by pathogens and parasites. This concept represents a means for the scientific integration of ancient wisdom with advanced medicine, constituting a possible boost for more sustainable food and functional food innovation and design.
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Reilly EE, Brown TA, Frank GKW. Perceptual Dysfunction in Eating Disorders. Curr Top Behav Neurosci 2024. [PMID: 38730196 DOI: 10.1007/7854_2024_470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2024]
Abstract
Eating disorders (EDs) are characterized by abnormal responses to food and weight-related stimuli and are associated with significant distress, impairment, and poor outcomes. Because many of the cardinal symptoms of EDs involve disturbances in perception of one's body or abnormal affective or cognitive reactions to food intake and how that affects one's size, there has been longstanding interest in characterizing alterations in sensory perception among differing ED diagnostic groups. Within the current review, we aimed to critically assess the existing research on exteroceptive and interoceptive perception and how sensory perception may influence ED behavior. Overall, existing research is most consistent regarding alterations in taste, visual, tactile, and gastric-specific interoceptive processing in EDs, with emerging work indicating elevated respiratory and cardiovascular sensitivity. However, this work is far from conclusive, with most studies unable to speak to the precise etiology of observed perceptual differences in these domains and disentangle these effects from affective and cognitive processes observed within EDs. Further, existing knowledge regarding perceptual disturbances in EDs is limited by heterogeneity in methodology, lack of multimodal assessment protocols, and inconsistent attention to different ED diagnoses. We propose several new avenues for improving neurobiology-informed research on sensory processing to generate actionable knowledge that can inform the development of innovative interventions for these serious disorders.
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Affiliation(s)
- Erin E Reilly
- Department of Psychiatry and Behavioral Science, University of California, San Francisco, San Francisco, CA, USA
| | - Tiffany A Brown
- Department of Psychology, Auburn University, Auburn, AL, USA
| | - Guido K W Frank
- Department of Psychiatry, University of California, San Diego, CA, USA.
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4
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Mu S, Stieger M, Boesveldt S. Can humans smell tastants? Chem Senses 2024; 49:bjad054. [PMID: 38175732 PMCID: PMC10807988 DOI: 10.1093/chemse/bjad054] [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: 07/21/2023] [Indexed: 01/06/2024] Open
Abstract
Although studies have shown that olfaction may contribute to the perception of tastant, literature is scarce or circumstantial, especially in humans. This study aims to (i) explore whether humans can perceive solutions of basic prototypical tastants through orthonasal and retronasal olfaction and (ii) to examine what volatile odor compounds (VOCs) underlie this ability. Solutions of 5 basic tastants (sucrose, sodium chloride, citric acid, monosodium glutamate [MSG], quinine) dissolved in water, and 2 fatty acids (oleic and linoleic acid) dissolved in mineral oil were prepared. Triangle discrimination tests were performed (n = 41 in duplicate) to assess whether the tastant solutions can be distinguished from blanks (solvents) through ortho- and retronasal olfaction. Participants were able to distinguish all tastant solutions from blank through orthonasal olfaction. Only sucrose, sodium chloride, oleic acid, and linoleic acid were distinguished from blank by retronasal olfaction. Ethyl dichloroacetate, methylene chloride, and/or acetone were identified in the headspace of sucrose, MSG, and quinine solutions but not in the headspace of water, sodium chloride, and citric acid solutions. Fat oxidation compounds such as alcohols and aldehydes were detected in the headspace of the oleic and linoleic acid solutions but not the mineral oil. We conclude that prototypical tastant solutions can be discriminated from water and fatty acid solutions from mineral oil through orthonasal olfaction. Differences in the volatile headspace composition between blanks and tastant solutions may have facilitated the olfactory discrimination. These findings can have methodological implications for future studies assessing gustatory perception using these prototypical taste compounds.
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Affiliation(s)
- Shuo Mu
- Division of Human Nutrition and Health, Wageningen University and Research, Wageningen, The Netherlands
| | - Markus Stieger
- Division of Human Nutrition and Health, Wageningen University and Research, Wageningen, The Netherlands
| | - Sanne Boesveldt
- Division of Human Nutrition and Health, Wageningen University and Research, Wageningen, The Netherlands
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5
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Caremoli F, Huynh J, Lagishetty V, Markovic D, Braun J, Dong TS, Jacobs JP, Sternini C. Microbiota-Dependent Upregulation of Bitter Taste Receptor Subtypes in the Mouse Large Intestine in High-Fat Diet-Induced Obesity. Nutrients 2023; 15:4145. [PMID: 37836428 PMCID: PMC10574285 DOI: 10.3390/nu15194145] [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: 08/05/2023] [Revised: 09/19/2023] [Accepted: 09/22/2023] [Indexed: 10/15/2023] Open
Abstract
Bitter taste receptors (Tas2rs in mice) detect bitterness, a warning signal for toxins and poisons, and are expressed in enteroendocrine cells. We tested the hypothesis that Tas2r138 and Tas2r116 mRNAs are modulated by microbiota alterations induced by a long-term high-fat diet (HFD) and antibiotics (ABX) (ampicillin and neomycin) administered in drinking water. Cecum and colon specimens and luminal contents were collected from C57BL/6 female and male mice for qRT-PCR and microbial luminal 16S sequencing. HFD with/without ABX significantly increased body weight and fat mass at 4, 6, and 8 weeks. Tas2r138 and Tas2r116 mRNAs were significantly increased in mice fed HFD for 8 weeks vs. normal diet, and this increase was prevented by ABX. There was a distinct microbiota separation in each experimental group and significant changes in the composition and diversity of microbiome in mice fed a HFD with/without ABX. Tas2r mRNA expression in HFD was associated with several genera, particularly with Akkermansia, a Gram-negative mucus-resident bacterium. These studies indicate that luminal bacterial composition is affected by sex, diet, and ABX and support a microbial dependent upregulation of Tas2rs in HFD-induced obesity, suggesting an adaptive host response to specific diet-induced dysbiosis.
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Affiliation(s)
- Filippo Caremoli
- Division of Digestive Diseases, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA; (F.C.); (J.H.); (V.L.); (T.S.D.); (J.P.J.)
- Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA;
| | - Jennifer Huynh
- Division of Digestive Diseases, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA; (F.C.); (J.H.); (V.L.); (T.S.D.); (J.P.J.)
- Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA;
- Department of Neurobiology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Venu Lagishetty
- Division of Digestive Diseases, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA; (F.C.); (J.H.); (V.L.); (T.S.D.); (J.P.J.)
- Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA;
| | - Daniela Markovic
- Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA;
| | - Jonathan Braun
- Inflammatory Bowel and Immunobiology Institute, Cedars Sinai Medical Center, Los Angeles, CA 90048, USA;
| | - Tien S. Dong
- Division of Digestive Diseases, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA; (F.C.); (J.H.); (V.L.); (T.S.D.); (J.P.J.)
- Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA;
| | - Jonathan P. Jacobs
- Division of Digestive Diseases, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA; (F.C.); (J.H.); (V.L.); (T.S.D.); (J.P.J.)
- Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA;
- Division of Gastroenterology, Hepatology and Parenteral Nutrition, VA Greater Los Angeles Healthcare System, Los Angeles, CA 90073, USA
| | - Catia Sternini
- Division of Digestive Diseases, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA; (F.C.); (J.H.); (V.L.); (T.S.D.); (J.P.J.)
- Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA;
- Department of Neurobiology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
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6
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Pieroni A, Morini G, Piochi M, Sulaiman N, Kalle R, Haq SM, Devecchi A, Franceschini C, Zocchi DM, Migliavada R, Prakofjewa J, Sartori M, Krigas N, Ahmad M, Torri L, Sõukand R. Bitter Is Better: Wild Greens Used in the Blue Zone of Ikaria, Greece. Nutrients 2023; 15:3242. [PMID: 37513661 PMCID: PMC10385191 DOI: 10.3390/nu15143242] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 07/10/2023] [Accepted: 07/19/2023] [Indexed: 07/30/2023] Open
Abstract
The current study reports an ethnobotanical field investigation of traditionally gathered and consumed wild greens (Chorta) in one of the five so-called Blue Zones in the world: Ikaria Isle, Greece. Through 31 semi-structured interviews, a total of 56 wild green plants were documented along with their culinary uses, linguistic labels, and locally perceived tastes. Most of the gathered greens were described as bitter and associated with members of Asteraceae and Brassicaceae botanical families (31%), while among the top-quoted wild greens, species belonging to these two plant families accounted for 50% of the wild vegetables, which were consumed mostly cooked. Cross-cultural comparison with foraging in other areas of the central-eastern Mediterranean and the Near East demonstrated a remarkable overlapping of Ikarian greens with Cretan and Sicilian, as well as in the prevalence of bitter-tasting botanical genera. Important differences with other wild greens-related food heritage were found, most notably with the Armenian and Kurdish ones, which do not commonly feature many bitter greens. The proven role of extra-oral bitter taste receptors in the modulation of gastric emptying, glucose absorption and crosstalk with microbiota opens new ways of looking at these differences, in particular with regard to possible health implications. The present study is also an important attempt to preserve and document the bio-cultural gastronomic heritage of Chorta as a quintessential part of the Mediterranean diet. The study recommends that nutritionists, food scientists, and historians, as well as policymakers and practitioners, pay the required attention to traditional rural dietary systems as models of sustainable health.
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Affiliation(s)
- Andrea Pieroni
- University of Gastronomic Sciences, Piazza Vittorio Emanuele II 9, 12042 Pollenzo, Italy
- Department of Medical Analysis, Tishk International University, Erbil 44001, Iraq
| | - Gabriella Morini
- University of Gastronomic Sciences, Piazza Vittorio Emanuele II 9, 12042 Pollenzo, Italy
| | - Maria Piochi
- University of Gastronomic Sciences, Piazza Vittorio Emanuele II 9, 12042 Pollenzo, Italy
| | - Naji Sulaiman
- University of Gastronomic Sciences, Piazza Vittorio Emanuele II 9, 12042 Pollenzo, Italy
- Department of Ethnology, Charles University, 116 38 Prague, Czech Republic
| | - Raivo Kalle
- University of Gastronomic Sciences, Piazza Vittorio Emanuele II 9, 12042 Pollenzo, Italy
- Estonian Literary Museum, Vanemuise 42, 51003 Tartu, Estonia
| | - Shiekh Marifatul Haq
- Department of Ethnobotany, Institute of Botany, Ilia State University, 0162 Tbilisi, Georgia
| | - Andrea Devecchi
- University of Gastronomic Sciences, Piazza Vittorio Emanuele II 9, 12042 Pollenzo, Italy
| | - Cinzia Franceschini
- University of Gastronomic Sciences, Piazza Vittorio Emanuele II 9, 12042 Pollenzo, Italy
| | - Dauro M Zocchi
- University of Gastronomic Sciences, Piazza Vittorio Emanuele II 9, 12042 Pollenzo, Italy
| | - Riccardo Migliavada
- University of Gastronomic Sciences, Piazza Vittorio Emanuele II 9, 12042 Pollenzo, Italy
| | - Julia Prakofjewa
- Department of Environmental Sciences, Informatics and Statistics, Ca' Foscari University of Venice, Via Torino 155, 30172 Venezia, Italy
| | - Matteo Sartori
- Department of Environmental Sciences, Informatics and Statistics, Ca' Foscari University of Venice, Via Torino 155, 30172 Venezia, Italy
| | - Nikos Krigas
- Institute of Plant Breeding and Genetic Resources, Hellenic Agricultural Organization Demeter, 57001 Thessaloniki, Greece
| | - Mushtaq Ahmad
- Department of Plant Sciences, Quaid-i-Azam University, Islamabad 45320, Pakistan
| | - Luisa Torri
- University of Gastronomic Sciences, Piazza Vittorio Emanuele II 9, 12042 Pollenzo, Italy
| | - Renata Sõukand
- Department of Environmental Sciences, Informatics and Statistics, Ca' Foscari University of Venice, Via Torino 155, 30172 Venezia, Italy
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7
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Angotzi AR, Leal E, Puchol S, Cerdá-Reverter JM, Morais S. Exploring the potential for an evolutionarily conserved role of the taste 1 receptor gene family in gut sensing mechanisms of fish. ANIMAL NUTRITION 2022; 11:293-308. [PMID: 36263402 PMCID: PMC9563615 DOI: 10.1016/j.aninu.2022.08.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 06/15/2022] [Accepted: 08/09/2022] [Indexed: 11/08/2022]
Abstract
In this study, we investigated the transcriptional spatio-temporal dynamics of the taste 1 receptor (T1R) gene family repertoire in seabream (Sparus aurata [sa]), during larval ontogeny and in adult tissues. In early larval development, saT1R expression arises heterochronously, i.e. the extraoral taste-related perception in the gastrointestinal tract (GIT) anticipates first exogenous feeding (at 9 days post hatching [dph]), followed by the buccal/intraoral perception from 14 dph onwards, supporting the hypothesis that the early onset of the molecular machinery underlying saT1R expression in the GIT is not induced by food but rather genetically hardwired. During adulthood, we characterized the expression patterns of saT1R within specific tissues (n = 4) distributed in oropharingeal, GIT and brain regions substantiating their functional versatility as chemosensory signaling players to a variety of biological functions beyond oral taste sensation. Further, we provided for the first time direct evidences in fish for mRNA co-expression of a subset of saT1R genes (mostly saT1R3, i.e. the common subunit of the heterodimeric T1R complexes for the detection of “sweet” and “umami” substances), with the selected gut peptides ghrelin (ghr), cholecystokinin (cck), hormone peptide yy (pyy) and proglucagon (pg). Each peptide defines the enteroendocrine cells (ECCs) identity, and establishes on morphological basis, a direct link for T1R chemosensing in the regulation of fish digestive processes. Finally, we analyzed the spatial gene expression patterns of 2 taste signaling components functionally homologous to the mammalian G(i)α subunit gustducin, namely saG(i)α1 and saG(i)α2, and demonstrated their co-localization with the saT1R3 in EECs, thus validating their direct involvement in taste-like transduction mechanisms of the fish GIT. In conclusion, data provide new insights in the evolutionary conservation of gut sensing in fish suggesting a conserved role for nutrient sensors modulating entero-endocrine secretion.
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8
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Bhatia V, de Jesus VC, Shaik FA, Jaggupilli A, Singh N, Chelikani P, Atukorallaya D. Extraoral expression and characterization of bitter taste receptors in
Astyanax mexicanus
(Mexican Tetra Fish). FASEB Bioadv 2022; 4:574-584. [PMID: 36089978 PMCID: PMC9447421 DOI: 10.1096/fba.2022-00032] [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: 03/18/2022] [Revised: 04/29/2022] [Accepted: 05/04/2022] [Indexed: 11/11/2022] Open
Affiliation(s)
- Vikram Bhatia
- Manitoba Chemosensory Biology Research Group and Department of Oral Biology University of Manitoba Dr. Gerald Niznick College of Dentistry, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB R3E0W2 Canada
- Children’s Hospital Research Institute of Manitoba (CHRIM), Winnipeg MB R3E3P4 Canada
| | - Vivianne Cruz de Jesus
- Manitoba Chemosensory Biology Research Group and Department of Oral Biology University of Manitoba Dr. Gerald Niznick College of Dentistry, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB R3E0W2 Canada
- Children’s Hospital Research Institute of Manitoba (CHRIM), Winnipeg MB R3E3P4 Canada
| | - Feroz Ahmed Shaik
- Manitoba Chemosensory Biology Research Group and Department of Oral Biology University of Manitoba Dr. Gerald Niznick College of Dentistry, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB R3E0W2 Canada
| | - Appalaraju Jaggupilli
- Manitoba Chemosensory Biology Research Group and Department of Oral Biology University of Manitoba Dr. Gerald Niznick College of Dentistry, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB R3E0W2 Canada
| | - Nisha Singh
- Manitoba Chemosensory Biology Research Group and Department of Oral Biology University of Manitoba Dr. Gerald Niznick College of Dentistry, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB R3E0W2 Canada
| | - Prashen Chelikani
- Manitoba Chemosensory Biology Research Group and Department of Oral Biology University of Manitoba Dr. Gerald Niznick College of Dentistry, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB R3E0W2 Canada
- Children’s Hospital Research Institute of Manitoba (CHRIM), Winnipeg MB R3E3P4 Canada
| | - Devi Atukorallaya
- Manitoba Chemosensory Biology Research Group and Department of Oral Biology University of Manitoba Dr. Gerald Niznick College of Dentistry, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB R3E0W2 Canada
- Children’s Hospital Research Institute of Manitoba (CHRIM), Winnipeg MB R3E3P4 Canada
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Shirakawa T, Toyono T, Inoue A, Matsubara T, Kawamoto T, Kokabu S. Factors Regulating or Regulated by Myogenic Regulatory Factors in Skeletal Muscle Stem Cells. Cells 2022; 11:cells11091493. [PMID: 35563799 PMCID: PMC9104119 DOI: 10.3390/cells11091493] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 04/25/2022] [Accepted: 04/26/2022] [Indexed: 11/23/2022] Open
Abstract
MyoD, Myf5, myogenin, and MRF4 (also known as Myf6 or herculin) are myogenic regulatory factors (MRFs). MRFs are regarded as master transcription factors that are upregulated during myogenesis and influence stem cells to differentiate into myogenic lineage cells. In this review, we summarize MRFs, their regulatory factors, such as TLE3, NF-κB, and MRF target genes, including non-myogenic genes such as taste receptors. Understanding the function of MRFs and the physiology or pathology of satellite cells will contribute to the development of cell therapy and drug discovery for muscle-related diseases.
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Affiliation(s)
- Tomohiko Shirakawa
- Division of Orofacial Functions and Orthodontics, Department of Health Improvement, Kyushu Dental University, Kitakyushu 803-8580, Japan; (T.S.); (A.I.); (T.K.)
- Division of Molecular Signaling and Biochemistry, Department of Health Improvement, Kyushu Dental University, Kitakyushu 803-8580, Japan;
| | - Takashi Toyono
- Division of Anatomy, Department of Health Promotion, Kyushu Dental University, Kitakyushu 803-8580, Japan;
| | - Asako Inoue
- Division of Orofacial Functions and Orthodontics, Department of Health Improvement, Kyushu Dental University, Kitakyushu 803-8580, Japan; (T.S.); (A.I.); (T.K.)
- Division of Molecular Signaling and Biochemistry, Department of Health Improvement, Kyushu Dental University, Kitakyushu 803-8580, Japan;
| | - Takuma Matsubara
- Division of Molecular Signaling and Biochemistry, Department of Health Improvement, Kyushu Dental University, Kitakyushu 803-8580, Japan;
| | - Tatsuo Kawamoto
- Division of Orofacial Functions and Orthodontics, Department of Health Improvement, Kyushu Dental University, Kitakyushu 803-8580, Japan; (T.S.); (A.I.); (T.K.)
| | - Shoichiro Kokabu
- Division of Molecular Signaling and Biochemistry, Department of Health Improvement, Kyushu Dental University, Kitakyushu 803-8580, Japan;
- Correspondence: ; Tel.: +81-93-582-1131; Fax: +81-93-285-6000
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Spence C. The tongue map and the spatial modulation of taste perception. Curr Res Food Sci 2022; 5:598-610. [PMID: 35345819 PMCID: PMC8956797 DOI: 10.1016/j.crfs.2022.02.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Revised: 02/09/2022] [Accepted: 02/10/2022] [Indexed: 12/14/2022] Open
Abstract
There is undoubtedly a spatial component to our experience of gustatory stimulus qualities such as sweet, bitter, salty, sour, and umami, however its importance is currently unknown. Taste thresholds have been shown to differ at different locations within the oral cavity where gustatory receptors are found. However, the relationship between the stimulation of particular taste receptors and the subjective spatially-localized experience of taste qualities is uncertain. Although the existence of the so-called ‘tongue map’ has long been discredited, the psychophysical evidence clearly demonstrates significant (albeit small) differences in taste sensitivity across the tongue, soft palate, and pharynx (all sites where taste buds have been documented). Biases in the perceived localization of gustatory stimuli have also been reported, often resulting from tactile capture (i.e., a form of crossmodal, or multisensory, interaction). At the same time, varying responses to supratheshold tastants along the tongue's anterior-posterior axis have putatively been linked to the ingestion-ejection response. This narrative review highlights what is currently known concerning the spatial aspects of gustatory perception, considers how such findings might be explained, given the suggested balanced distribution of taste receptors for each basic taste quality where taste papillae are present, and suggests why knowing about such differences may be important. The existence of the tongue map has long been discredited. Taste receptors in the oral cavity respond to all tastes regardless of their location. Human psychophysical data highlights a significant spatial modulation of taste perception in the oral cavity. Highly-controlled studies of taste psychophysics rarely capture the full multisensory experience associated with eating and drinking.
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Toda Y, Hayakawa T, Itoigawa A, Kurihara Y, Nakagita T, Hayashi M, Ashino R, Melin AD, Ishimaru Y, Kawamura S, Imai H, Misaka T. Evolution of the primate glutamate taste sensor from a nucleotide sensor. Curr Biol 2021; 31:4641-4649.e5. [PMID: 34450087 DOI: 10.1016/j.cub.2021.08.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 06/21/2021] [Accepted: 08/02/2021] [Indexed: 12/19/2022]
Abstract
Taste perception plays an essential role in food selection. Umami (savory) tastes are sensed by a taste receptor complex, T1R1/T1R3, that detects proteinogenic amino acids.1 High sensitivity to l-glutamate (l-Glu) is a characteristic of human T1R1/T1R3, but the T1R1/T1R3 of other vertebrates does not consistently show this l-Glu response.1,2 Here, we demonstrate that the l-Glu sensitivity of T1R1/T1R3 is a derived state that has evolved repeatedly in large primates that rely on leaves as protein sources, after their divergence from insectivorous ancestors. Receptor expression experiments show that common amino acid substitutions at ligand binding sites that render T1R1/T1R3 sensitive to l-Glu occur independently at least three times in primate evolution. Meanwhile T1R1/T1R3 senses 5'-ribonucleotides as opposed to l-Glu in several mammalian species, including insectivorous primates. Our chemical analysis reveal that l-Glu is one of the major free amino acids in primate diets and that insects, but not leaves, contain large amounts of free 5'-ribonucleotides. Altering the ligand-binding preference of T1R1/T1R3 from 5'-ribonucleotides to l-Glu might promote leaf consumption, overcoming bitter and aversive tastes. Altogether, our results provide insight into the foraging ecology of a diverse mammalian radiation and help reveal how evolution of sensory genes facilitates invasion of new ecological niches.
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Affiliation(s)
- Yasuka Toda
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan; Department of Agricultural Chemistry, School of Agriculture, Meiji University, Kawasaki, Kanagawa 214-8571, Japan; Japan Society for the Promotion of Science, Tokyo 102-0083, Japan
| | - Takashi Hayakawa
- Faculty of Environmental Earth Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan; Primate Research Institute, Kyoto University, Inuyama, Aichi 484-8506, Japan; Japan Monkey Centre, Inuyama, Aichi 484-0081, Japan
| | - Akihiro Itoigawa
- Japan Society for the Promotion of Science, Tokyo 102-0083, Japan; Primate Research Institute, Kyoto University, Inuyama, Aichi 484-8506, Japan
| | - Yosuke Kurihara
- Primate Research Institute, Kyoto University, Inuyama, Aichi 484-8506, Japan; Center for Education and Research in Field Sciences, Faculty of Agriculture, Shizuoka University, Hamamatsu, Shizuoka 431-3532, Japan
| | - Tomoya Nakagita
- Department of Agricultural Chemistry, School of Agriculture, Meiji University, Kawasaki, Kanagawa 214-8571, Japan; Proteo-Science Center, Ehime University, Matsuyama, Ehime 790-8577, Japan
| | - Masahiro Hayashi
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwanoha, Kashiwa, Chiba 277-8562, Japan
| | - Ryuichi Ashino
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwanoha, Kashiwa, Chiba 277-8562, Japan
| | - Amanda D Melin
- Department of Anthropology and Archaeology, University of Calgary, Alberta T2N 1N4, Canada; Department of Medical Genetics and Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Yoshiro Ishimaru
- Department of Agricultural Chemistry, School of Agriculture, Meiji University, Kawasaki, Kanagawa 214-8571, Japan
| | - Shoji Kawamura
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwanoha, Kashiwa, Chiba 277-8562, Japan.
| | - Hiroo Imai
- Primate Research Institute, Kyoto University, Inuyama, Aichi 484-8506, Japan.
| | - Takumi Misaka
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan.
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12
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Obikane Y, Toyono T, Kokabu S, Matsuyama K, Kataoka S, Nakatomi M, Hosokawa R, Seta Y. Myogenic differentiation 1 and transcription factor 12 activate the gene expression of mouse taste receptor type 1 member 1. J Oral Biosci 2021; 63:420-428. [PMID: 34492379 DOI: 10.1016/j.job.2021.08.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 08/25/2021] [Accepted: 08/26/2021] [Indexed: 11/30/2022]
Abstract
OBJECTIVES Myogenic differentiation 1 (Myod1) is involved in the expression of taste receptor type 1 member 1 (Tas1r1) during myogenic differentiation. Further, the target genes of Myod1 participate in transcriptional control, muscle development, and synaptic function. We examined, for the first time, the function of Myod1 in the transcriptional regulation of Tas1r1. METHODS ENCODE chromatin immunoprecipitation and sequencing (ChIP-seq) data of myogenically differentiated C2C12 cells were analyzed to identify the Myod1 and transcription factor 12 (Tcf12) binding sites in the Tas1r1 promoter region. Luciferase reporter assays, DNA affinity precipitation assays, and co-immunoprecipitation assays were also performed to identify the functions of Myod1, Tcf12, and Krüppel-like factor 5 (Klf5). RESULTS Based on ENCODE ChIP-seq, Myod1 bound to the Tas1r1 promoter region containing E-boxes 1-3. Luciferase reporter assays revealed that site-directed E-box1 mutations significantly reduced promoter activation induced by Myod1 overexpression. According to the DNA affinity precipitation assay and co-immunoprecipitation assay, Myod1 formed a heterodimer with Tcf12 and bound to E-box1. Further, Klf5 bound to the GT box near E-box1, activating Tas1r1 expression. CONCLUSIONS During myogenic differentiation, the Myod1/Tcf12 heterodimer, in collaboration with Klf5, binds to E-box1 and activates Tas1r1 expression.
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Affiliation(s)
- Yui Obikane
- Division of Oral Reconstruction and Rehabilitation, Department of Oral Functions, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-ku, Kitakyushu 803-8580, Japan
| | - Takashi Toyono
- Division of Anatomy, Department of Health Promotion, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-ku, Kitakyushu 803-8580, Japan.
| | - Shoichiro Kokabu
- Division of Molecular Signaling and Biochemistry, Department of Health Promotion, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-ku, Kitakyushu 803-8580, Japan
| | - Kae Matsuyama
- Division of Anatomy, Department of Health Promotion, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-ku, Kitakyushu 803-8580, Japan
| | - Shinji Kataoka
- Division of Anatomy, Department of Health Promotion, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-ku, Kitakyushu 803-8580, Japan
| | - Mitsushiro Nakatomi
- Division of Anatomy, Department of Health Promotion, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-ku, Kitakyushu 803-8580, Japan
| | - Ryuji Hosokawa
- Division of Oral Reconstruction and Rehabilitation, Department of Oral Functions, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-ku, Kitakyushu 803-8580, Japan
| | - Yuji Seta
- Division of Anatomy, Department of Health Promotion, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-ku, Kitakyushu 803-8580, Japan
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13
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The Etiologies and Considerations of Dysgeusia: A Review of Literature. J Oral Biosci 2021; 63:319-326. [PMID: 34487857 DOI: 10.1016/j.job.2021.08.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 08/25/2021] [Accepted: 08/26/2021] [Indexed: 01/21/2023]
Abstract
BACKGROUND Dysgeusia is a prevalent qualitative gustatory impairment that may affect food intake and quality of life. The facial (VII), glossopharyngeal (IX), and vagus (X) nerves are the three cranial nerves responsible for sensing taste. Typically, dysgeusia is considered a general term for all taste disorders. In addition, dysgeusia may be a symptom of underlying systemic conditions such as diabetes mellitus, chronic kidney disease, respiratory infections, and nutritional deficiencies. Various subjective and objective diagnostic approaches are available to aid clinicians, each with its own set of benefits and drawbacks. HIGHLIGHTS Taste impairment can lead to a lack of enjoyment while eating, food aversion, and malnutrition, resulting in a decrease in the quality of life and loss of muscle mass. Therefore, the present review aims to address the probable etiologies, diagnostic aids, and management of dysgeusia. A broad search for studies was conducted using PubMed, Web of Science, Scopus, and Google Scholar. In addition, relevant studies found in the references of the selected articles were also studied. CONCLUSION Oral health care providers should be aware of the possible etiologies of dysgeusia, diagnostic tools, and treatment options. Accurate diagnosis of the cause of taste dysfunction has a significant impact on the management of taste impairment.
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14
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Koyama S, Kondo K, Ueha R, Kashiwadani H, Heinbockel T. Possible Use of Phytochemicals for Recovery from COVID-19-Induced Anosmia and Ageusia. Int J Mol Sci 2021; 22:8912. [PMID: 34445619 PMCID: PMC8396277 DOI: 10.3390/ijms22168912] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/10/2021] [Accepted: 08/13/2021] [Indexed: 12/14/2022] Open
Abstract
The year 2020 became the year of the outbreak of coronavirus, SARS-CoV-2, which escalated into a worldwide pandemic and continued into 2021. One of the unique symptoms of the SARS-CoV-2 disease, COVID-19, is the loss of chemical senses, i.e., smell and taste. Smell training is one of the methods used in facilitating recovery of the olfactory sense, and it uses essential oils of lemon, rose, clove, and eucalyptus. These essential oils were not selected based on their chemical constituents. Although scientific studies have shown that they improve recovery, there may be better combinations for facilitating recovery. Many phytochemicals have bioactive properties with anti-inflammatory and anti-viral effects. In this review, we describe the chemical compounds with anti- inflammatory and anti-viral effects, and we list the plants that contain these chemical compounds. We expand the review from terpenes to the less volatile flavonoids in order to propose a combination of essential oils and diets that can be used to develop a new taste training method, as there has been no taste training so far. Finally, we discuss the possible use of these in clinical settings.
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Affiliation(s)
- Sachiko Koyama
- Department of Chemistry, Indiana University, Bloomington, IN 47405, USA
| | - Kenji Kondo
- Department of Otolaryngology, Faculty of Medicine, The University of Tokyo, Tokyo 113-8655, Japan;
| | - Rumi Ueha
- Department of Otolaryngology, Faculty of Medicine, The University of Tokyo, Tokyo 113-8655, Japan;
- Swallowing Center, The University of Tokyo Hospital, Tokyo 113-8655, Japan
| | - Hideki Kashiwadani
- Department of Physiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544, Japan;
| | - Thomas Heinbockel
- Department of Anatomy, College of Medicine, Howard University, Washington, DC 20059, USA
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15
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Morini G, Winnig M, Vennegeerts T, Borgonovo G, Bassoli A. Vanillin Activates Human Bitter Taste Receptors TAS2R14, TAS2R20, and TAS2R39. Front Nutr 2021; 8:683627. [PMID: 34307435 PMCID: PMC8298857 DOI: 10.3389/fnut.2021.683627] [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: 03/22/2021] [Accepted: 06/09/2021] [Indexed: 12/11/2022] Open
Abstract
Vanilla is widely used in food preparation worldwide for its sensory properties, mainly related to its fragrance, being vanillin the major compound present in the processed vanilla. Vanillin is also known to elicit bitterness as a secondary sensory sensation, but the molecular mechanism of its bitterness has never been reported. Assay buffers of vanillin were tested in vitro on all known 25 human bitter taste receptors TAS2Rs. Three receptors, TAS2R14, TAS2R20, and TAS2R39, were activated, showing that these receptors are mediating the bitterness of vanillin. The result could be useful to improve the overall sensory profile of this broadly used food ingredient, but even more could represent the starting point for further studies to investigate the potential of vanillin in sensory nutrition and other pharmaceutical applications.
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Affiliation(s)
| | - Marcel Winnig
- IMAX Discovery GmbH, Dortmund, Germany.,Axxam S.p.A. Bresso, Italy
| | - Timo Vennegeerts
- IMAX Discovery GmbH, Dortmund, Germany.,Axxam S.p.A. Bresso, Italy
| | - Gigliola Borgonovo
- DeFENS - Department of Food, Environmental and Nutritional Sciences, University of Milan, Milan, Italy
| | - Angela Bassoli
- DeFENS - Department of Food, Environmental and Nutritional Sciences, University of Milan, Milan, Italy
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16
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Risso D, Drayna D, Tofanelli S, Morini G. Open questions in sweet, umami and bitter taste genetics. CURRENT OPINION IN PHYSIOLOGY 2021. [DOI: 10.1016/j.cophys.2020.12.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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17
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Development of epithelial cholinergic chemosensory cells of the urethra and trachea of mice. Cell Tissue Res 2021; 385:21-35. [PMID: 33616728 PMCID: PMC8270884 DOI: 10.1007/s00441-021-03424-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 01/24/2021] [Indexed: 12/24/2022]
Abstract
Cholinergic chemosensory cells (CCC) are infrequent epithelial cells with immunosensor function, positioned in mucosal epithelia preferentially near body entry sites in mammals including man. Given their adaptive capacity in response to infection and their role in combatting pathogens, we here addressed the time points of their initial emergence as well as their postnatal development from first exposure to environmental microbiota (i.e., birth) to adulthood in urethra and trachea, utilizing choline acetyltransferase (ChAT)-eGFP reporter mice, mice with genetic deletion of MyD88, toll-like receptor-2 (TLR2), TLR4, TLR2/TLR4, and germ-free mice. Appearance of CCC differs between the investigated organs. CCC of the trachea emerge during embryonic development at E18 and expand further after birth. Urethral CCC show gender diversity and appear first at P6-P10 in male and at P11-P20 in female mice. Urethrae and tracheae of MyD88- and TLR-deficient mice showed significantly fewer CCC in all four investigated deficient strains, with the effect being most prominent in the urethra. In germ-free mice, however, CCC numbers were not reduced, indicating that TLR2/4-MyD88 signaling, but not vita-PAMPs, governs CCC development. Collectively, our data show a marked postnatal expansion of CCC populations with distinct organ-specific features, including the relative impact of TLR2/4-MyD88 signaling. Strong dependency on this pathway (urethra) correlates with absence of CCC at birth and gender-specific initial development and expansion dynamics, whereas moderate dependency (trachea) coincides with presence of first CCC at E18 and sex-independent further development.
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18
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Kohanski MA, Brown L, Orr M, Tan LH, Adappa ND, Palmer JN, Rubenstein RC, Cohen NA. Bitter taste receptor agonists regulate epithelial two-pore potassium channels via cAMP signaling. Respir Res 2021; 22:31. [PMID: 33509163 PMCID: PMC7844973 DOI: 10.1186/s12931-021-01631-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 01/20/2021] [Indexed: 11/20/2022] Open
Abstract
Background Epithelial solitary chemosensory cell (tuft cell) bitter taste signal transduction occurs through G protein coupled receptors and calcium-dependent signaling pathways. Type II taste cells, which utilize the same bitter taste signal transduction pathways, may also utilize cyclic adenosine monophosphate (cAMP) as an independent signaling messenger in addition to calcium. Methods In this work we utilized specific pharmacologic inhibitors to interrogate the short circuit current (Isc) of polarized nasal epithelial cells mounted in Ussing chambers to assess the electrophysiologic changes associated with bitter agonist (denatonium) treatment. We also assessed release of human β-defensin-2 from polarized nasal epithelial cultures following treatment with denatonium benzoate and/or potassium channel inhibitors. Results We demonstrate that the bitter taste receptor agonist, denatonium, decreases human respiratory epithelial two-pore potassium (K2P) current in polarized nasal epithelial cells mounted in Ussing chambers. Our data further suggest that this occurs via a cAMP-dependent signaling pathway. We also demonstrate that this decrease in potassium current lowers the threshold for denatonium to stimulate human β-defensin-2 release. Conclusions These data thus demonstrate that, in addition to taste transducing calcium-dependent signaling, bitter taste receptor agonists can also activate cAMP-dependent respiratory epithelial signaling pathways to modulate K2P currents. Bitter-agonist regulation of potassium currents may therefore serve as a means of rapid regional epithelial signaling, and further study of these pathways may provide new insights into regulation of mucosal ionic composition and innate mechanisms of epithelial defense.
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Affiliation(s)
- Michael A Kohanski
- Department of Otorhinolaryngology-Head and Neck Surgery, Division of Rhinology, University of Pennsylvania Medical Center, Perelman School of Medicine, 5th Floor Ravdin Building, 3400 Spruce Street, Philadelphia, PA, USA.
| | - Lauren Brown
- Cystic Fibrosis Center, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Melissa Orr
- Cystic Fibrosis Center, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Li Hui Tan
- Department of Otorhinolaryngology-Head and Neck Surgery, Division of Rhinology, University of Pennsylvania Medical Center, Perelman School of Medicine, 5th Floor Ravdin Building, 3400 Spruce Street, Philadelphia, PA, USA
| | - Nithin D Adappa
- Department of Otorhinolaryngology-Head and Neck Surgery, Division of Rhinology, University of Pennsylvania Medical Center, Perelman School of Medicine, 5th Floor Ravdin Building, 3400 Spruce Street, Philadelphia, PA, USA
| | - James N Palmer
- Department of Otorhinolaryngology-Head and Neck Surgery, Division of Rhinology, University of Pennsylvania Medical Center, Perelman School of Medicine, 5th Floor Ravdin Building, 3400 Spruce Street, Philadelphia, PA, USA
| | - Ronald C Rubenstein
- Cystic Fibrosis Center, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Department of Pediatrics, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA.,Division of Allergy and Pulmonary Medicine, Department of Pediatrics, Washington University in St. Louis School of Medicine, St. Louis, MO, USA
| | - Noam A Cohen
- Department of Otorhinolaryngology-Head and Neck Surgery, Division of Rhinology, University of Pennsylvania Medical Center, Perelman School of Medicine, 5th Floor Ravdin Building, 3400 Spruce Street, Philadelphia, PA, USA.,Corporal Michael J. Crescenz Veterans Administration Medical Center, Philadelphia, PA, USA.,Monell Chemical Senses Institute, Philadelphia, PA, USA
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19
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Veronese S, Merigo F, Sbarbati A. Did we forget the diffuse chemosensory system when studying COVID-19? Immunol Lett 2021; 231:26-27. [PMID: 33428993 PMCID: PMC7834028 DOI: 10.1016/j.imlet.2021.01.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Accepted: 01/05/2021] [Indexed: 12/22/2022]
Affiliation(s)
- Sheila Veronese
- Department of Neuroscience, Biomedicine and Movement, University of Verona, 37134, Verona, Italy.
| | - Flavia Merigo
- Department of Neuroscience, Biomedicine and Movement, University of Verona, 37134, Verona, Italy
| | - Andrea Sbarbati
- Department of Neuroscience, Biomedicine and Movement, University of Verona, 37134, Verona, Italy
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20
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Bray SC, Carek PJ. How bitter taste influences nutrition and health in primary care. J Family Med Prim Care 2020; 9:3205-3208. [PMID: 33102271 PMCID: PMC7567205 DOI: 10.4103/jfmpc.jfmpc_305_20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 03/14/2020] [Accepted: 03/25/2020] [Indexed: 12/15/2022] Open
Abstract
Sensitivity to bitter tastes has a genetic basis which is partly mediated by the TAS2R3 gene. Existing research on how this gene influences dietary habits and successful strategies for encouraging the incorporation of additional fruits and vegetables into individuals’ diets is discussed. We propose that knowledge of a patient's status TAS2R3 genotype could help physicians develop personalized nutritional strategies using exposure and associative conditioning techniques to encourage optimal nutrition.
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Affiliation(s)
- Stefania C Bray
- Department of Community Health and Family Medicine, University of Florida, Gainesville, FL, United States
| | - Peter J Carek
- Department of Community Health and Family Medicine, University of Florida, Gainesville, FL, United States
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21
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Risso D, Drayna D, Morini G. Alteration, Reduction and Taste Loss: Main Causes and Potential Implications on Dietary Habits. Nutrients 2020; 12:E3284. [PMID: 33120898 PMCID: PMC7693910 DOI: 10.3390/nu12113284] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 09/29/2020] [Accepted: 10/23/2020] [Indexed: 01/04/2023] Open
Abstract
Our sense of taste arises from the sensory information generated after compounds in the oral cavity and oropharynx activate taste receptor cells situated on taste buds. This produces the perception of sweet, bitter, salty, sour, or umami stimuli, depending on the chemical nature of the tastant. Taste impairments (dysgeusia) are alterations of this normal gustatory functioning that may result in complete taste losses (ageusia), partial reductions (hypogeusia), or over-acuteness of the sense of taste (hypergeusia). Taste impairments are not life-threatening conditions, but they can cause sufficient discomfort and lead to appetite loss and changes in eating habits, with possible effects on health. Determinants of such alterations are multiple and consist of both genetic and environmental factors, including aging, exposure to chemicals, drugs, trauma, high alcohol consumption, cigarette smoking, poor oral health, malnutrition, and viral upper respiratory infections including influenza. Disturbances or loss of smell, taste, and chemesthesis have also emerged as predominant neurological symptoms of infection by the recent Coronavirus disease 2019 (COVID-19), caused by Severe Acute Respiratory Syndrome Coronavirus strain 2 (SARS-CoV-2), as well as by previous both endemic and pandemic coronaviruses such as Middle East Respiratory Syndrome Coronavirus (MERS-CoV) and SARS-CoV. This review is focused on the main causes of alteration, reduction, and loss of taste and their potential repercussion on dietary habits and health, with a special focus on the recently developed hypotheses regarding the mechanisms through which SARS-CoV-2 might alter taste perception.
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Affiliation(s)
- Davide Risso
- Ferrero Group, Soremartec Italia Srl, 12051 Alba, CN, Italy
| | - Dennis Drayna
- National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD 20892, USA;
| | - Gabriella Morini
- University of Gastronomic Sciences, Piazza Vittorio Emanuele 9, Bra, 12042 Pollenzo, CN, Italy;
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22
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Insights into the Function and Evolution of Taste 1 Receptor Gene Family in the Carnivore Fish Gilthead Seabream ( Sparus aurata). Int J Mol Sci 2020; 21:ijms21207732. [PMID: 33086689 PMCID: PMC7594079 DOI: 10.3390/ijms21207732] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 10/14/2020] [Accepted: 10/16/2020] [Indexed: 11/24/2022] Open
Abstract
A plethora of molecular and functional studies in tetrapods has led to the discovery of multiple taste 1 receptor (T1R) genes encoding G-protein coupled receptors (GPCRs) responsible for sweet (T1R2 + T1R3) and umami (T1R1 + T1R3) taste. In fish, the T1R gene family repertoires greatly expanded because of several T1R2 gene duplications, and recent studies have shown T1R2 functional divergence from canonical mammalian sweet taste perceptions, putatively as an adaptive mechanism to develop distinct feeding strategies in highly diverse aquatic habitats. We addressed this question in the carnivore fish gilthead seabream (Sparus aurata), a model species of aquaculture interest, and found that the saT1R gene repertoire consists of eight members including saT1R1, saT1R3 and six saT1R2a-f gene duplicates, adding further evidence to the evolutionary complexity of fishT1Rs families. To analyze saT1R taste functions, we first developed a stable gene reporter system based on Ca2+-dependent calcineurin/NFAT signaling to examine specifically in vitro the responses of a subset of saT1R heterodimers to L-amino acids (L-AAs) and sweet ligands. We show that although differentially tuned in sensitivity and magnitude of responses, saT1R1/R3, saT1R2a/R3 and saT1R2b/R3 may equally serve to transduce amino acid taste sensations. Furthermore, we present preliminary information on the potential involvement of the Gi protein alpha subunits saGαi1 and saGαi2 in taste signal transduction.
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23
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Chen J, Larson ED, Anderson CB, Agarwal P, Frank DN, Kinnamon SC, Ramakrishnan VR. Expression of Bitter Taste Receptors and Solitary Chemosensory Cell Markers in the Human Sinonasal Cavity. Chem Senses 2020; 44:483-495. [PMID: 31231752 DOI: 10.1093/chemse/bjz042] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Some bitter taste receptors (TAS2R gene products) are expressed in the human sinonasal cavity and may function to detect airborne irritants. The expression of all 25 human bitter taste receptors and their location within the upper airway is not yet clear. The aim of this study is to characterize the presence and distribution of TAS2R transcripts and solitary chemosensory cells (SCCs) in different locations of the human sinonasal cavity. Biopsies were obtained from human subjects at up to 4 different sinonasal anatomic sites. PCR, microarray, and qRT-PCR were used to examine gene transcript expression. The 25 human bitter taste receptors as well as the sweet/umami receptor subunit, TAS1R3, and canonical taste signaling effectors are expressed in sinonasal tissue. All 25 human bitter taste receptors are expressed in the human upper airway, and expression of these gene products was higher in the ethmoid sinus than nasal cavity locations. Fluorescent in situ hybridization demonstrates that epithelial TRPM5 and TAS2R38 are expressed in a rare cell population compared with multiciliated cells, and at times, consistent with SCC morphology. Secondary analysis of published human sinus single-cell RNAseq data did not uncover TAS2R or canonical taste transduction transcripts in multiciliated cells. These findings indicate that the sinus has higher expression of SCC markers than the nasal cavity in chronic rhinosinusitis patients, comprising a rare cell type. Biopsies obtained from the ethmoid sinus may serve as the best location for study of human upper airway taste receptors and SCCs.
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Affiliation(s)
- Jingguo Chen
- Department of Otolaryngology-Head and Neck Surgery, The Second Affiliated Hospital, Xi'an Jiaotong University Health Science Center, Xi'an, China.,Department of Otolaryngology, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA
| | - Eric D Larson
- Department of Otolaryngology, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA.,Rocky Mountain Taste and Smell Center, Aurora, CO, USA
| | - Catherine B Anderson
- Department of Otolaryngology, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA.,Rocky Mountain Taste and Smell Center, Aurora, CO, USA
| | | | - Daniel N Frank
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Sue C Kinnamon
- Department of Otolaryngology, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA.,Rocky Mountain Taste and Smell Center, Aurora, CO, USA
| | - Vijay R Ramakrishnan
- Department of Otolaryngology, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA.,Rocky Mountain Taste and Smell Center, Aurora, CO, USA
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Moriconi E, Feraco A, Marzolla V, Infante M, Lombardo M, Fabbri A, Caprio M. Neuroendocrine and Metabolic Effects of Low-Calorie and Non-Calorie Sweeteners. Front Endocrinol (Lausanne) 2020; 11:444. [PMID: 32765425 PMCID: PMC7378387 DOI: 10.3389/fendo.2020.00444] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 06/05/2020] [Indexed: 12/18/2022] Open
Abstract
Since excessive sugar consumption has been related to the development of chronic metabolic diseases prevalent in the western world, the use of sweeteners has gradually increased worldwide over the last few years. Although low- and non-calorie sweeteners may represent a valuable tool to reduce calorie intake and prevent weight gain, studies investigating the safety and efficacy of these compounds in the short- and long-term period are scarce and controversial. Therefore, future studies will need to elucidate the potential beneficial and/or detrimental effects of different types of sweeteners on metabolic health (energy balance, appetite, body weight, cardiometabolic risk factors) in healthy subjects and patients with diabetes, obesity and metabolic syndrome. In this regard, the impact of different sweeteners on central nervous system, gut hormones and gut microbiota is important, given the strong implications that changes in such systems may have for human health. The aim of this narrative review is to summarize the current evidence for the neuroendocrine and metabolic effects of sweeteners, as well as their impact on gut microbiota. Finally, we briefly discuss the advantages of the use of sweeteners in the context of very-low calorie ketogenic diets.
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Affiliation(s)
- Eleonora Moriconi
- Laboratory of Cardiovascular Endocrinology, IRCCS San Raffaele Pisana, Rome, Italy
- Section of Medical Pathophysiology, Food Science and Endocrinology, Department of Experimental Medicine, Sapienza University of Rome, Rome, Italy
| | - Alessandra Feraco
- Laboratory of Cardiovascular Endocrinology, IRCCS San Raffaele Pisana, Rome, Italy
| | - Vincenzo Marzolla
- Laboratory of Cardiovascular Endocrinology, IRCCS San Raffaele Pisana, Rome, Italy
| | - Marco Infante
- Unit of Endocrinology and Metabolic Diseases, Department of Systems Medicine, CTO A. Alesini Hospital, University of Rome Tor Vergata, Rome, Italy
| | - Mauro Lombardo
- Department of Human Sciences and Promotion of the Quality of Life, San Raffaele Roma Open University, Rome, Italy
| | - Andrea Fabbri
- Unit of Endocrinology and Metabolic Diseases, Department of Systems Medicine, CTO A. Alesini Hospital, University of Rome Tor Vergata, Rome, Italy
| | - Massimiliano Caprio
- Laboratory of Cardiovascular Endocrinology, IRCCS San Raffaele Pisana, Rome, Italy
- Department of Human Sciences and Promotion of the Quality of Life, San Raffaele Roma Open University, Rome, Italy
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25
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Ruppert AL, Keshavarz M, Winterberg S, Oberwinkler J, Kummer W, Schütz B. Advillin is a tuft cell marker in the mouse alimentary tract. J Mol Histol 2020; 51:421-435. [PMID: 32617896 PMCID: PMC7368872 DOI: 10.1007/s10735-020-09893-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 06/25/2020] [Indexed: 12/12/2022]
Abstract
Tuft cells are a rare population of chemosensory cells at the mucosal surface epithelia of hollow organs. Their name-giving morphological feature is an apical tuft of stiff microvilli. Accordingly, the actin-binding protein, villin, was identified as one of the first tuft cell markers in immunohistochemical analysis. Unfortunately, villin expression is not restricted to tuft cells, but is also prominent e.g. in enterocytes, which limits the use of this gene as a marker and as an experimental tool to genetically target tuft cells. Here, we report that the villin-related protein, advillin, is a specific tuft cell marker in the gastro-intestinal and biliary tract epithelia. In situ hybridization and immunohistochemistry revealed that advillin expression, unlike villin, was restricted to solitary cholinergic tuft cells in the mucosal linings of the small and large intestine, and in the gall bladder. In the glandular stomach, villin and advillin mRNA were present in all epithelial cells, while detectable protein levels were confined to solitary tuft cells. Advillin expression was no longer detectable in the mucosa of the intestinal and biliary tract from Pou2f3 deficient mice that lack tuft cells. Finally, crossing Avil-Cre transgenic mice with a double-fluorescent reporter mouse line resulted in specific targeting of gastro-intestinal and biliary tuft cells. Our analysis introduces advillin as a selective marker and tool in histological and functional analysis of the alimentary tract tuft cell system.
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Affiliation(s)
- Anna-Lena Ruppert
- Institute for Anatomy and Cell Biology, Philipps-University, Robert-Koch-Straße 8, 35037, Marburg, Germany
| | - Maryam Keshavarz
- Institute for Anatomy and Cell Biology, Justus-Liebig-University, Aulweg 123, 35385, Gießen, Germany
| | - Sarah Winterberg
- Institute for Anatomy and Cell Biology, Philipps-University, Robert-Koch-Straße 8, 35037, Marburg, Germany
| | - Johannes Oberwinkler
- Institute for Physiology and Pathophysiology, Philipps-University, Deutschhausstraße 1, 35037, Marburg, Germany
| | - Wolfgang Kummer
- Institute for Anatomy and Cell Biology, Justus-Liebig-University, Aulweg 123, 35385, Gießen, Germany
| | - Burkhard Schütz
- Institute for Anatomy and Cell Biology, Philipps-University, Robert-Koch-Straße 8, 35037, Marburg, Germany.
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Welcome MO. The bitterness of genitourinary infections: Properties, ligands of genitourinary bitter taste receptors and mechanisms linking taste sensing to inflammatory processes in the genitourinary tract. Eur J Obstet Gynecol Reprod Biol 2020; 247:101-110. [PMID: 32088528 DOI: 10.1016/j.ejogrb.2020.02.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 02/03/2020] [Accepted: 02/13/2020] [Indexed: 01/04/2023]
Abstract
BACKGROUND Though, first identified in the gastrointestinal tract, bitter taste receptors are now believed to be ubiquitously expressed in several regions of the body, including the respiratory tract, where they play a critical role in sensing and clearance of excess metabolic substrates, toxins, debris, and pathogens. More recently, bitter taste receptor expression has been reported in cells, tissues and organs of the genitourinary (GU) system, suggesting that these receptors may play an integral role in mediating inflammatory responses to microbial aggression in the GU tract. However, the mechanisms, linking bitter taste receptor sensing with inflammatory responses are not exactly clear. Here, I review recent data on the properties and ligands of bitter taste receptors and suggest mechanisms of bitter taste receptor signaling in the GU tract, and the molecular pathways that link taste sensing to inflammatory responses in GU tract. METHOD Computer-aided search was conducted in Scopus, PubMed, Web of Science and Google Scholar for relevant peer-reviewed articles published between 1990 and 2018, investigating the functional implication of bitter taste receptors in GU infections, using the following keywords: extra-oral bitter taste receptors, bitter taste receptors, GU bitter taste receptors, kidney OR renal OR ureteral OR urethral OR bladder OR detrusor smooth muscle OR testes OR spermatozoa OR prostate OR vaginal OR cervix OR ovarian OR endometrial OR myometrial OR placenta OR cutaneous bitter taste receptors. To identify research gaps on etiopathogenesis of GU infections/inflammation, additional search was conducted using the following keywords: GU inflammatory signaling, GU microbes, GU bacteria, GU virus, GU protozoa, GU microbial metabolites, and GU infection. The retrieved articles were filtered and further screened for relevance according to the aim of the study. A narrative review was performed for selected literatures. RESULTS Bitter taste receptors of the GU tract may constitute essential components of the pathogenetic mechanisms of GU infections/inflammation that are activated by microbial components, known as quorum sensing signal molecules. Based on accumulating evidences, indicating that taste receptors may signal downstream to activate inflammatory cascades, in addition to the nitric oxide-induced microbicidal effects produced upon taste receptor activation, it is suggested that the anti-inflammatory activities of bitter taste receptor stimulation are mediated via pathways involving the nuclear factor κB by downstream signaling of the metabolic and stress sensors, adenosine monophosphate-activated protein kinase and nicotinamide adenine dinucleotide-dependent silent mating type information regulation 2 homolog 1 (sirtuin 1), resulting to the synthesis of anti-inflammatory cytokines/chemokines, and antimicrobial factors, which ultimately, under normal conditions, leads to the elimination of microbial aggression. CONCLUSIONS GU bitter taste receptors may represent critical players in GU tract infections/inflammation. Bitter taste receptors may serve as important therapeutic target for treatment of a number of infectious diseases that affect the GU tract.
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Affiliation(s)
- Menizibeya O Welcome
- Department of Physiology, Faculty of Basic Medical Sciences, College of Health Sciences, Nile University of Nigeria, Abuja, Nigeria.
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27
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Distribution pattern and molecular signature of cholinergic tuft cells in human gastro-intestinal and pancreatic-biliary tract. Sci Rep 2019; 9:17466. [PMID: 31767912 PMCID: PMC6877571 DOI: 10.1038/s41598-019-53997-3] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 11/05/2019] [Indexed: 01/01/2023] Open
Abstract
Despite considerable recent insight into the molecular phenotypes and type 2 innate immune functions of tuft cells in rodents, there is sparse knowledge about the region-specific presence and molecular phenotypes of tuft cells in the human digestive tract. Here, we traced cholinergic tuft cells throughout the human alimentary tract with immunohistochemistry and deciphered their region-specific distribution and biomolecule coexistence patterns. While absent from the human stomach, cholinergic tuft cells localized to villi and crypts in the small and large intestines. In the biliary tract, they were present in the epithelium of extra-hepatic peribiliary glands, but not observed in the epithelia of the gall bladder and the common duct of the biliary tract. In the pancreas, solitary cholinergic tuft cells were frequently observed in the epithelia of small and medium-size intra- and inter-lobular ducts, while they were absent from acinar cells and from the main pancreatic duct. Double immunofluorescence revealed co-expression of choline acetyltransferase with structural (cytokeratin 18, villin, advillin) tuft cell markers and eicosanoid signaling (cyclooxygenase 1, hematopoietic prostaglandin D synthase, 5-lipoxygenase activating protein) biomolecules. Our results indicate that region-specific cholinergic signaling of tuft cells plays a role in mucosal immunity in health and disease, especially in infection and cancer.
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Hollenhorst MI, Jurastow I, Nandigama R, Appenzeller S, Li L, Vogel J, Wiederhold S, Althaus M, Empting M, Altmüller J, Hirsch AKH, Flockerzi V, Canning BJ, Saliba A, Krasteva‐Christ G. Tracheal brush cells release acetylcholine in response to bitter tastants for paracrine and autocrine signaling. FASEB J 2019; 34:316-332. [DOI: 10.1096/fj.201901314rr] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 10/20/2019] [Accepted: 10/22/2019] [Indexed: 12/20/2022]
Affiliation(s)
| | - Innokentij Jurastow
- Institute of Anatomy and Cell Biology Justus‐Liebig‐University of Giessen Giessen Germany
- Department of Anesthesiology and Intensive Care Medicine (CS) University Hospital Charité Humboldt University of Berlin Berlin Germany
| | - Rajender Nandigama
- Institute of Anatomy and Cell Biology University of Würzburg Würzburg Germany
| | - Silke Appenzeller
- Comprehensive Cancer Centre Mainfranken University of Würzburg Würzburg Germany
| | - Lei Li
- Core Unit SysMed University of Würzburg Würzburg Germany
| | - Jörg Vogel
- Helmholtz Institute for RNA‐based Infection Research (HIRI) Helmholtz‐Centre for Infection Research (HZI) Würzburg Germany
| | - Stephanie Wiederhold
- Institute of Anatomy and Cell Biology Justus‐Liebig‐University of Giessen Giessen Germany
| | - Mike Althaus
- School of Natural and Environmental Sciences Newcastle University Newcastle upon Tyne United Kingdom
| | - Martin Empting
- Department of Drug Design and Optimization (DDOP) Helmholtz‐Institute for Pharmaceutical Research Saarland (HIPS)‐Helmholtz Centre for Infection Research (HZI) Saarbrücken Germany
- Department of Pharmacy Saarland University Saarbrücken Germany
- German Centre for Infection Research (DZIF) Saarbrücken Germany
| | - Janine Altmüller
- Cologne Centre for Genomics University of Cologne Cologne Germany
| | - Anna K. H. Hirsch
- Department of Drug Design and Optimization (DDOP) Helmholtz‐Institute for Pharmaceutical Research Saarland (HIPS)‐Helmholtz Centre for Infection Research (HZI) Saarbrücken Germany
- Department of Pharmacy Saarland University Saarbrücken Germany
- German Centre for Infection Research (DZIF) Saarbrücken Germany
| | - Veit Flockerzi
- Institute of Experimental and Clinical Pharmacology and Toxicology/PZMS Saarland University Homburg Germany
| | - Brendan J. Canning
- Department of Medicine Division of Allergy and Clinical Immunology School of Medicine Johns Hopkins University Baltimore MD USA
| | - Antoine‐Emmanuel Saliba
- Helmholtz Institute for RNA‐based Infection Research (HIRI) Helmholtz‐Centre for Infection Research (HZI) Würzburg Germany
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Abstract
PURPOSE OF REVIEW The consumption of foods and beverages containing non-nutritive sweeteners (NNS) has increased worldwide over the last three decades. Consumers' choice of NNS rather than sugar or other nutritive sweeteners may be attributable to their potential to reduce weight gain. RECENT FINDINGS It is not clear what the effects of NNS consumption are on glycaemic control and the incidence of type 2 diabetes. This review aims to examine this question in epidemiological, human intervention and animal studies. It is not clear that NNS consumption has an effect on the incidence of type 2 diabetes or on glycaemic control even though there is some evidence for the modification of the microbiome and for interaction with sweet taste receptors in the oral cavity and the intestines' modification of secretion of glucagon-like peptide-1 (GLP-1), peptide YY (PYY), ghrelin and glucose-dependent insulinotropic polypeptide (GIP), which may affect glycaemia following consumption of NNS. In conclusion, long-term studies of NNS consumption are required to draw a firm conclusion about the role of NNS consumption on glycaemic control.
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Affiliation(s)
- Yoona Kim
- Department of Food and Nutrition, College of Natural Science, Gyeongsang National University, Jinju, Republic of Korea
| | - Jennifer B Keogh
- Division of Health Sciences, School of Pharmacy and Medical Sciences, University of South Australia, GPO Box 2471, Adelaide, SA, 5000, Australia
| | - Peter M Clifton
- Division of Health Sciences, School of Pharmacy and Medical Sciences, University of South Australia, GPO Box 2471, Adelaide, SA, 5000, Australia.
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Sarnelli G, Annunziata G, Magno S, Oriolo C, Savastano S, Colao A. Taste and the Gastrointestinal tract: from physiology to potential therapeutic target for obesity. INTERNATIONAL JOURNAL OF OBESITY SUPPLEMENTS 2019; 9:1-9. [PMID: 31391920 DOI: 10.1038/s41367-019-0012-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Flavor is the combination of gustatory, olfactory and trigeminal sensations, representing the three main sensory pathways that allow detecting environmental chemical substances. Taste, in particular, is a complex chemosensory path that allows identification of substances present in ingested foods and beverages. In this manuscript, we propose a conceptual roadmap from aspects related to the evolution and the physiological role of taste, up to the current knowledge about its implication in the modulation of a healthy state, or obesity. More specifically, we focused on the role of stimulation of taste receptors in releasing gut hormones (also known as enterohormones), and their effects on the regulation of food intake, by inducing satiety, either by locally acting (in the gastrointestinal tract), or centrally (in the brain). Recent evidence demonstrated that some enterohormones are able to modulate gastrointestinal motility, thus affecting an orexigenic responses in the central nervous system. In keeping with this, we discuss the ability of the gustatory system to be a final checkpoint control for food intake regulation, and we speculate about taste perception manipulation in the management of obesity.
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Affiliation(s)
- Giovanni Sarnelli
- 1Department of Clinical Medicine and Surgery, Division of Gastroenterology, University of Naples Federico II, Naples, Italy
| | | | - Silvia Magno
- Obesity Center at the Endocrinology Unit, Department of Clinical and Experimental Medicine, Pisa, Italy
| | - Claudia Oriolo
- 4Endocrinology Unit, Medical Department of Care Continuity and Disability, University of Bologna, Bologna, Italy
| | - Silvia Savastano
- 5Dipartimento di Medicina Clinica e Chirurgia, Unit of Endocrinology, Federico II University Medical School of Naples, Napoli, Italy
| | - Annamaria Colao
- 5Dipartimento di Medicina Clinica e Chirurgia, Unit of Endocrinology, Federico II University Medical School of Naples, Napoli, Italy
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Hirata Y, Toyono T, Kokabu S, Obikane Y, Kataoka S, Nakatomi M, Masaki C, Hosokawa R, Seta Y. Krüppel-like factor 5 (Klf5) regulates expression of mouse T1R1 amino acid receptor gene (Tas1r1) in C2C12 myoblast cells. Biomed Res 2019; 40:67-78. [PMID: 30982802 DOI: 10.2220/biomedres.40.67] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
T1R1 and T1R3 are receptors expressed in taste buds that detect L-amino acids. These receptors are also expressed throughout diverse organ systems, such as the digestive system and muscle tissue, and are thought to function as amino acid sensors. The mechanism of transcriptional regulation of the mouse T1R1 gene (Tas1r1) has not been determined; therefore, in this study, we examined the function of Tas1r1 promoter in the mouse myoblast cell line, C2C12. Luciferase reporter assays showed that a 148-bp region upstream of the ATG start codon of Tas1r1 had a promoter activity. The GT box in the Tas1r1 promoter was conserved in the dog, human, mouse, and pig. Site-directed mutagenesis of this GT box significantly reduced the promoter activation. The GT box in promoters is a recurring motif for Sp/KLF family members. RNAi-mediated depletion of Sp4 and Klf5 decreased Tas1r1 expression, while overexpression of Klf5, but not Sp4, significantly increased Tas1r1 expression. The ENCODE data of chromatin immunoprecipitation and sequencing (ChIP-seq) showed that Klf5 bound to the GT box during the myogenic differentiation. Furthermore, the Klf5 knockout cell lines led to a considerable decrease in the levels of Tas1r1 expression. Collectively, these results showed that Klf5 binds to the GT box in the Tas1r1 promoter and regulates Tas1r1 expression in C2C12 cells.
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Affiliation(s)
- Yuki Hirata
- Division of Oral Reconstruction and Rehabilitation, Department of Oral Functions, Kyushu Dental University
| | - Takashi Toyono
- Division of Anatomy, Department of Health Promotion, Kyushu Dental University
| | - Shoichiro Kokabu
- Division of Molecular Signaling and Biochemistry, Department of Health Promotion, Kyushu Dental University
| | - Yui Obikane
- Division of Oral Reconstruction and Rehabilitation, Department of Oral Functions, Kyushu Dental University
| | - Shinji Kataoka
- Division of Anatomy, Department of Health Promotion, Kyushu Dental University
| | - Mitsushiro Nakatomi
- Division of Anatomy, Department of Health Promotion, Kyushu Dental University
| | - Chihiro Masaki
- Division of Oral Reconstruction and Rehabilitation, Department of Oral Functions, Kyushu Dental University
| | - Ryuji Hosokawa
- Division of Oral Reconstruction and Rehabilitation, Department of Oral Functions, Kyushu Dental University
| | - Yuji Seta
- Division of Anatomy, Department of Health Promotion, Kyushu Dental University
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Robino A, Concas MP, Catamo E, Gasparini P. A Brief Review of Genetic Approaches to the Study of Food Preferences: Current Knowledge and Future Directions. Nutrients 2019; 11:nu11081735. [PMID: 31357559 PMCID: PMC6722914 DOI: 10.3390/nu11081735] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 07/17/2019] [Accepted: 07/25/2019] [Indexed: 02/07/2023] Open
Abstract
Genetic variation plays a crucial role in individual differences in food preferences which ultimately influence food selection and health. Our current understanding of this pathway has been informed through twin studies (to assess the heritability of food preferences), candidate gene studies, and genome-wide association studies (GWAS). However, most of this literature is mainly focused on genes previously identified as having taste or smell functions. New data suggests that genes not associated with taste or smell perception may be involved in food preferences and contribute to health outcomes. This review highlights these emerging findings and suggests a polygenic risk assessment approach to explore new relationships between food preferences and health risks.
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Affiliation(s)
- Antonietta Robino
- Institute for Maternal and Child Health, IRCCS "Burlo Garofolo", Via dell'Istria 65/1, 34137, Trieste, Italy.
| | - Maria Pina Concas
- Institute for Maternal and Child Health, IRCCS "Burlo Garofolo", Via dell'Istria 65/1, 34137, Trieste, Italy
| | - Eulalia Catamo
- Institute for Maternal and Child Health, IRCCS "Burlo Garofolo", Via dell'Istria 65/1, 34137, Trieste, Italy
| | - Paolo Gasparini
- Institute for Maternal and Child Health, IRCCS "Burlo Garofolo", Via dell'Istria 65/1, 34137, Trieste, Italy
- Department of Medical Sciences, University of Trieste, Strada di Fiume, 447, 34149 Trieste, Italy
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Shrungeswara AH, Unnikrishnan MK. Evolution of dietary preferences and the innate urge to heal: Drug discovery lessons from Ayurveda. J Ayurveda Integr Med 2019; 10:222-226. [PMID: 29576440 PMCID: PMC6822145 DOI: 10.1016/j.jaim.2017.08.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 07/12/2017] [Accepted: 08/01/2017] [Indexed: 12/05/2022] Open
Abstract
Highly specialized and functionally integrated cognitive systems facilitate hedonistic and healthy food preferences. Guided by survival needs, flavor preferences not only select safe, nutritious dietary components, but also those with negligible calorific value but significant health benefits, for example, spices. Feeding behavior, both innate and acquired, is guided not only by taste receptors on the tongue but also visceral organs. The gustatory cortex receives information from all senses, not just taste, suggesting multiple checkpoints in predicting and evaluating healthy foods. Ayurvedic interpretation of 'rasa' as chemistry is compatible with medicinal value of diets because, taste and odor are chemosensory perceptions. As flavor and taste are linked to the chemical structure of compounds, taste might offer clues about pharmacological activity. Ayurvedic idea of vipaka, or post digestive perception of taste, recognizes the extended role of taste receptors beyond the tongue and stretching into the viscera. Ayurvedic wisdom is consistent with evolutionary guideposts that suggest three successive stages of nutritional appraisal: before, during, and after ingesting food. While olfaction induces affinity or revulsion even before ingestion, gustatory receptors on the tongue evaluates nutritional value upon contact, and the chemoreceptors in the deeper metabolic systems probably pronounce the final verdict on the nutritive and health benefits of ingested substances. Alliesthesia, neophobia, and the extreme variation in human T2R genes (coding for bitterness receptors) illustrate the importance of adaptive learning of dietary preferences. These evolutionary clues are compatible with the Ayurvedic principle of 'rasa', in facilitating the process of drug discovery.
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Affiliation(s)
- Akhila Hosur Shrungeswara
- Department of Pharmacy Practice, Manipal College of Pharmaceutical Sciences, Manipal University, Karnataka, 576104, India
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34
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Lasconi C, Pifferi S, Hernandez-Clavijo A, Merigo F, Cecchini MP, Gonzalez-Velandia KY, Agostinelli E, Sbarbati A, Menini A. Bitter tastants and artificial sweeteners activate a subset of epithelial cells in acute tissue slices of the rat trachea. Sci Rep 2019; 9:8834. [PMID: 31222082 PMCID: PMC6586933 DOI: 10.1038/s41598-019-45456-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 06/07/2019] [Indexed: 02/06/2023] Open
Abstract
Bitter and sweet receptors (T2Rs and T1Rs) are expressed in many extra-oral tissues including upper and lower airways. To investigate if bitter tastants and artificial sweeteners could activate physiological responses in tracheal epithelial cells we performed confocal Ca2+ imaging recordings on acute tracheal slices. We stimulated the cells with denatonium benzoate, a T2R agonist, and with the artificial sweeteners sucralose, saccharin and acesulfame-K. To test cell viability we measured responses to ATP. We found that 39% of the epithelial cells responding to ATP also responded to bitter stimulation with denatonium benzoate. Moreover, artificial sweeteners activated different percentages of the cells, ranging from 5% for sucralose to 26% for saccharin, and 27% for acesulfame-K. By using carbenoxolone, a gap junction blocker, we excluded that responses were mainly mediated by Ca2+ waves through cell-to-cell junctions. Pharmacological experiments showed that both denatonium and artificial sweeteners induced a PLC-mediated release of Ca2+ from internal stores. In addition, bitter tastants and artificial sweeteners activated a partially overlapping subpopulation of tracheal epithelial cells. Our results provide new evidence that a subset of ATP-responsive tracheal epithelial cells from rat are activated by both bitter tastants and artificial sweeteners.
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Affiliation(s)
- Chiara Lasconi
- Department of Neurosciences, Biomedicine and Movement Sciences, Anatomy and Histology Section, University of Verona, School of Medicine, Verona, Italy
| | - Simone Pifferi
- Neurobiology Group, SISSA, International School for Advanced Studies, Trieste, Italy.
| | | | - Flavia Merigo
- Department of Neurosciences, Biomedicine and Movement Sciences, Anatomy and Histology Section, University of Verona, School of Medicine, Verona, Italy
| | - Maria Paola Cecchini
- Department of Neurosciences, Biomedicine and Movement Sciences, Anatomy and Histology Section, University of Verona, School of Medicine, Verona, Italy.
| | | | - Emilio Agostinelli
- Neurobiology Group, SISSA, International School for Advanced Studies, Trieste, Italy
| | - Andrea Sbarbati
- Department of Neurosciences, Biomedicine and Movement Sciences, Anatomy and Histology Section, University of Verona, School of Medicine, Verona, Italy
| | - Anna Menini
- Neurobiology Group, SISSA, International School for Advanced Studies, Trieste, Italy
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35
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Tuwani R, Wadhwa S, Bagler G. BitterSweet: Building machine learning models for predicting the bitter and sweet taste of small molecules. Sci Rep 2019; 9:7155. [PMID: 31073241 PMCID: PMC6509165 DOI: 10.1038/s41598-019-43664-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 04/12/2019] [Indexed: 01/29/2023] Open
Abstract
The dichotomy of sweet and bitter tastes is a salient evolutionary feature of human gustatory system with an innate attraction to sweet taste and aversion to bitterness. A better understanding of molecular correlates of bitter-sweet taste gradient is crucial for identification of natural as well as synthetic compounds of desirable taste on this axis. While previous studies have advanced our understanding of the molecular basis of bitter-sweet taste and contributed models for their identification, there is ample scope to enhance these models by meticulous compilation of bitter-sweet molecules and utilization of a wide spectrum of molecular descriptors. Towards these goals, our study provides a structured compilation of bitter, sweet and tasteless molecules and state-of-the-art machine learning models for bitter-sweet taste prediction (BitterSweet). We compare different sets of molecular descriptors for their predictive performance and further identify important features as well as feature blocks. The utility of BitterSweet models is demonstrated by taste prediction on large specialized chemical sets such as FlavorDB, FooDB, SuperSweet, Super Natural II, DSSTox, and DrugBank. To facilitate future research in this direction, we make all datasets and BitterSweet models publicly available, and present an end-to-end software for bitter-sweet taste prediction based on freely available chemical descriptors.
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Affiliation(s)
- Rudraksh Tuwani
- Complex Systems Laboratory, Center for Computational Biology, Indraprastha Institute of Information Technology (IIIT-Delhi), New Delhi, India
| | - Somin Wadhwa
- Complex Systems Laboratory, Center for Computational Biology, Indraprastha Institute of Information Technology (IIIT-Delhi), New Delhi, India
| | - Ganesh Bagler
- Complex Systems Laboratory, Center for Computational Biology, Indraprastha Institute of Information Technology (IIIT-Delhi), New Delhi, India.
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36
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Non-Nutritive Sweeteners and Their Implications on the Development of Metabolic Syndrome. Nutrients 2019; 11:nu11030644. [PMID: 30884834 PMCID: PMC6471792 DOI: 10.3390/nu11030644] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 03/12/2019] [Accepted: 03/13/2019] [Indexed: 12/18/2022] Open
Abstract
Individuals widely use non-nutritive sweeteners (NNS) in attempts to lower their overall daily caloric intake, lose weight, and sustain a healthy diet. There are insufficient scientific data that support the safety of consuming NNS. However, recent studies have suggested that NNS consumption can induce gut microbiota dysbiosis and promote glucose intolerance in healthy individuals that may result in the development of type 2 diabetes mellitus (T2DM). This sequence of events may result in changes in the gut microbiota composition through microRNA (miRNA)-mediated changes. The mechanism(s) by which miRNAs alter gene expression of different bacterial species provides a link between the consumption of NNS and the development of metabolic changes. Another potential mechanism that connects NNS to metabolic changes is the molecular crosstalk between the insulin receptor (IR) and G protein-coupled receptors (GPCRs). Here, we aim to highlight the role of NNS in obesity and discuss IR-GPCR crosstalk and miRNA-mediated changes, in the manipulation of the gut microbiota composition and T2DM pathogenesis.
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37
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Kanno N, Yoshida S, Kato T, Kato Y. Characteristic Localization of Neuronatin in Rat Testis, Hair Follicle, Tongue, and Pancreas. J Histochem Cytochem 2019; 67:495-509. [PMID: 30869556 DOI: 10.1369/0022155419836433] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Neuronatin (Nnat) is expressed in the pituitary, pancreas, and other tissues; however, the function of NNAT is still unclear. Recent studies have demonstrated that NNAT is localized in the sex-determining region Y-box 2-positive stem/progenitor cells in the developing rat pituitary primordium and is downregulated during differentiation into mature hormone-producing cells. Moreover, NNAT is widely localized in subcellular organelles, excluding the Golgi. Here, we further evaluated NNAT-positive cells and intracellular localization in embryonic and postnatal rat tissues such as the pancreas, tongue, whisker hair follicle, and testis. Immunohistochemistry revealed that NNAT was localized in undifferentiated cells (i.e., epithelial basal cells and basement cells in the papillae of the tongue and round and elongated spermatids of the testis) as well as in differentiated cells (insulin-positive cells and exocrine cells of the pancreas, taste receptor cells of the fungiform papilla, the inner root sheath of whisker hair follicles, and spermatozoa). In addition, NNAT exhibited novel intracellular localization in acrosomes in the spermatozoa. Because the endoplasmic reticulum (ER) is excluded from spermatozoa and sarco/ER Ca2+-ATPase isoform 2 (SERCA2) is absent from the inner root sheath, these findings suggested that NNAT localization in the ER and its interaction with SERCA2 are cell- or tissue-specific properties.
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Affiliation(s)
- Naoko Kanno
- Division of Life Science, Meiji University, Kanagawa, Japan
| | - Saishu Yoshida
- Institute of Endocrinology, Meiji University, Kanagawa, Japan
| | - Takako Kato
- Institute of Endocrinology, Meiji University, Kanagawa, Japan
| | - Yukio Kato
- Division of Life Science, Meiji University, Kanagawa, Japan.,Graduate School of Agriculture, Meiji University, Kanagawa, Japan.,Institute of Endocrinology, Meiji University, Kanagawa, Japan
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38
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Luddi A, Governini L, Wilmskötter D, Gudermann T, Boekhoff I, Piomboni P. Taste Receptors: New Players in Sperm Biology. Int J Mol Sci 2019; 20:E967. [PMID: 30813355 PMCID: PMC6413048 DOI: 10.3390/ijms20040967] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 02/13/2019] [Accepted: 02/18/2019] [Indexed: 12/21/2022] Open
Abstract
Taste receptors were first described as sensory receptors located on the tongue, where they are expressed in small clusters of specialized epithelial cells. However, more studies were published in recent years pointing to an expression of these proteins not only in the oral cavity but throughout the body and thus to a physiological role beyond the tongue. The recent observation that taste receptors and components of the coupled taste transduction cascade are also expressed during the different phases of spermatogenesis as well as in mature spermatozoa from mouse to humans and the overlap between the ligand spectrum of taste receptors with compounds in the male and female reproductive organs makes it reasonable to assume that sperm "taste" these different cues in their natural microenvironments. This assumption is assisted by the recent observations of a reproductive phenotype of different mouse lines carrying a targeted deletion of a taste receptor gene as well as the finding of a significant correlation between human male infertility and some polymorphisms in taste receptors genes. In this review, we depict recent findings on the role of taste receptors in male fertility, especially focusing on their possible involvement in mechanisms underlying spermatogenesis and post testicular sperm maturation. We also highlight the impact of genetic deletions of taste receptors, as well as their polymorphisms on male reproduction.
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Affiliation(s)
- Alice Luddi
- Department of Molecular and Developmental Medicine, Siena University, 53100 Siena, Italy.
| | - Laura Governini
- Department of Molecular and Developmental Medicine, Siena University, 53100 Siena, Italy.
| | - Dorke Wilmskötter
- Walther-Straub-Institute of Pharmacology and Toxicology, Ludwig-Maximilians-University, 80539 Munich, Germany.
| | - Thomas Gudermann
- Walther-Straub-Institute of Pharmacology and Toxicology, Ludwig-Maximilians-University, 80539 Munich, Germany.
| | - Ingrid Boekhoff
- Walther-Straub-Institute of Pharmacology and Toxicology, Ludwig-Maximilians-University, 80539 Munich, Germany.
| | - Paola Piomboni
- Department of Molecular and Developmental Medicine, Siena University, 53100 Siena, Italy.
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39
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Abstract
This chapter summarizes the available data about taste receptor functions and their role in perception of food with emphasis on the human system. In addition we illuminate the widespread presence of these receptors throughout the body and discuss some of their extraoral functions. Finally, we describe clinical aspects where taste receptor signaling could be relevant.
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Affiliation(s)
- Jonas C Töle
- Department of Molecular Genetics, German Institute of Human Nutrition Potsdam-Rehbruecke, Nuthetal, Germany
| | - Maik Behrens
- Leibniz-Institute for Food Systems Biology at the Technical University of Munich, Freising, Germany
| | - Wolfgang Meyerhof
- Center for Integrative Physiology and Molecular Medicine, Saarland University, Homburg, Germany.
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40
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Schier LA, Spector AC. The Functional and Neurobiological Properties of Bad Taste. Physiol Rev 2019; 99:605-663. [PMID: 30475657 PMCID: PMC6442928 DOI: 10.1152/physrev.00044.2017] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 05/18/2018] [Accepted: 06/30/2018] [Indexed: 12/12/2022] Open
Abstract
The gustatory system serves as a critical line of defense against ingesting harmful substances. Technological advances have fostered the characterization of peripheral receptors and have created opportunities for more selective manipulations of the nervous system, yet the neurobiological mechanisms underlying taste-based avoidance and aversion remain poorly understood. One conceptual obstacle stems from a lack of recognition that taste signals subserve several behavioral and physiological functions which likely engage partially segregated neural circuits. Moreover, although the gustatory system evolved to respond expediently to broad classes of biologically relevant chemicals, innate repertoires are often not in register with the actual consequences of a food. The mammalian brain exhibits tremendous flexibility; responses to taste can be modified in a specific manner according to bodily needs and the learned consequences of ingestion. Therefore, experimental strategies that distinguish between the functional properties of various taste-guided behaviors and link them to specific neural circuits need to be applied. Given the close relationship between the gustatory and visceroceptive systems, a full reckoning of the neural architecture of bad taste requires an understanding of how these respective sensory signals are integrated in the brain.
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Affiliation(s)
- Lindsey A Schier
- Department of Biological Sciences, University of Southern California , Los Angeles, California ; and Department of Psychology and Program in Neuroscience, Florida State University , Tallahassee, Florida
| | - Alan C Spector
- Department of Biological Sciences, University of Southern California , Los Angeles, California ; and Department of Psychology and Program in Neuroscience, Florida State University , Tallahassee, Florida
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41
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Kandel C, Schmidt P, Perniss A, Keshavarz M, Scholz P, Osterloh S, Althaus M, Kummer W, Deckmann K. ENaC in Cholinergic Brush Cells. Front Cell Dev Biol 2018; 6:89. [PMID: 30159312 PMCID: PMC6103785 DOI: 10.3389/fcell.2018.00089] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 07/25/2018] [Indexed: 12/17/2022] Open
Abstract
Cholinergic polymodal chemosensory cells in the mammalian urethra (urethral brush cells = UBC) functionally express the canonical bitter and umami taste transduction signaling cascade. Here, we aimed to determine whether UBC are functionally equipped for the perception of salt through ENaC (epithelial sodium channel). Cholinergic UBC were isolated from ChAT-eGFP reporter mice (ChAT = choline acetyltransferase). RT-PCR showed mRNA expression of ENaC subunits Scnn1a, Scnn1b, and Scnn1g in urethral epithelium and isolated UBC. Scnn1a could also be detected by next generation sequencing in 4/6 (66%) single UBC, two of them also expressed the bitter receptor Tas2R108. Strong expression of Scnn1a was seen in some urothelial umbrella cells and in 65% of UBC (30/46 cells) in a Scnn1a reporter mouse strain. Intracellular [Ca2+] was recorded in isolated UBC stimulated with the bitter substance denatonium benzoate (25 mM), ATP (0.5 mM) and NaCl (50 mM, on top of 145 mM Na+ and 153 mM Cl− baseline in buffer); mannitol (150 mM) served as osmolarity control. NaCl, but not mannitol, evoked an increase in intracellular [Ca2+] in 70% of the tested UBC. The NaCl-induced effect was blocked by the ENaC inhibitor amiloride (IC50 = 0.47 μM). When responses to both NaCl and denatonium were tested, all three possible positive response patterns occurred in a balanced distribution: 42% NaCl only, 33% denatonium only, 25% to both stimuli. A similar reaction pattern was observed with ATP and NaCl as test stimuli. About 22% of the UBC reacted to all three stimuli. Thus, NaCl evokes calcium responses in several UBC, likely involving an amiloride-sensitive channel containing α-ENaC. This feature does not define a new subpopulation of UBC, but rather emphasizes their polymodal character. The actual function of α-ENaC in cholinergic UBC—salt perception, homeostatic ion transport, mechanoreception—remains to be determined.
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Affiliation(s)
- Chrissy Kandel
- Institute for Anatomy and Cell Biology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Patricia Schmidt
- Institute for Anatomy and Cell Biology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Alexander Perniss
- Institute for Anatomy and Cell Biology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Maryam Keshavarz
- Institute for Anatomy and Cell Biology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Paul Scholz
- Department of Cell Physiology, Ruhr-University Bochum, Bochum, Germany
| | - Sabrina Osterloh
- Department of Cell Physiology, Ruhr-University Bochum, Bochum, Germany
| | - Mike Althaus
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Wolfgang Kummer
- Institute for Anatomy and Cell Biology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Klaus Deckmann
- Institute for Anatomy and Cell Biology, Justus-Liebig-University Giessen, Giessen, Germany
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42
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Fu Z, Ogura T, Luo W, Lin W. ATP and Odor Mixture Activate TRPM5-Expressing Microvillous Cells and Potentially Induce Acetylcholine Release to Enhance Supporting Cell Endocytosis in Mouse Main Olfactory Epithelium. Front Cell Neurosci 2018; 12:71. [PMID: 29615870 PMCID: PMC5869921 DOI: 10.3389/fncel.2018.00071] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 02/27/2018] [Indexed: 12/13/2022] Open
Abstract
The main olfactory epithelium (MOE) functions to detect odor molecules, provide an epithelial surface barrier, and remove xenobiotics from inhaled air. Mechanisms coordinating the activities of different cell types within the MOE to maintain these functions are poorly understood. Previously, we showed that superficially located microvillous cells (MCs) in the MOE expressing transient receptor potential channel M5 (TRPM5) are cholinergic and chemoresponsive and that they play an important role in maintaining odor responses and olfactory-guided behavior under challenging chemical environment. Here we investigated TRPM5-MC activation and subsequent paracrine regulation. Ca2+ imaging showed that TRPM5-MCs dose-dependently increase their intracellular Ca2+ levels in response to ATP, an important signaling molecule for airway mucociliary movement, and to an odor mixture. Pharmacological examination showed that the ATP responses are primarily mediated by P2X purinergic receptors. Interestingly, using the endocytosis dye pHrodo Red dextran, we found that chemical-activated TRPM5-MCs significantly increase the number of pHrodo-labeled puncta compared to controls without stimulation and compared to cells that do not respond to ATP or to the odor mixture. These results indicate potential vesicle recycling after release of the signaling molecule acetylcholine (ACh). Interestingly, TRPM5 knockout (KO) results in a decrease in ATP-induced pHrodo internalization. We further investigated cholinergic regulation of neighboring supporting cells (SCs). We found that ACh strongly elevates intracellular Ca2+ and potentiates pHrodo endocytosis in SCs. The ACh effects are diminished in the presence of atropine or M3 muscarinic receptor antagonist and in SCs lacking M3 receptors. Collectively, these data suggest that TRPM5-MCs may regulate the MOE’s multicellular network activity via cholinergic paracrine signaling for functional maintenance and adaptive plasticity.
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Affiliation(s)
- Ziying Fu
- Department of Biological Sciences, University of Maryland, Baltimore County, Baltimore, MD, United States
| | - Tatsuya Ogura
- Department of Biological Sciences, University of Maryland, Baltimore County, Baltimore, MD, United States
| | - Wangmei Luo
- Department of Biological Sciences, University of Maryland, Baltimore County, Baltimore, MD, United States
| | - Weihong Lin
- Department of Biological Sciences, University of Maryland, Baltimore County, Baltimore, MD, United States
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43
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Liu S, Lu S, Xu R, Atzberger A, Günther S, Wettschureck N, Offermanns S. Members of Bitter Taste Receptor Cluster Tas2r143/Tas2r135/Tas2r126 Are Expressed in the Epithelium of Murine Airways and Other Non-gustatory Tissues. Front Physiol 2017; 8:849. [PMID: 29163195 PMCID: PMC5670347 DOI: 10.3389/fphys.2017.00849] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 10/11/2017] [Indexed: 11/13/2022] Open
Abstract
The mouse bitter taste receptors Tas2r143, Tas2r135, and Tas2r126 are encoded by genes that cluster on chromosome 6 and have been suggested to be expressed under common regulatory elements. Previous studies indicated that the Tas2r143/Tas2r135/Tas2r126 cluster is expressed in the heart, but other organs had not been systematically analyzed. In order to investigate the expression of this bitter taste receptor gene cluster in non-gustatory tissues, we generated a BAC (bacterial artificial chromosome) based transgenic mouse line, expressing CreERT2 under the control of the Tas2r143 promoter. After crossing this line with a mouse line expressing EGFP after Cre-mediated recombination, we were able to validate the Tas2r143-CreERT2 transgenic mouse line and monitor the expression of Tas2r143. EGFP-positive cells, indicating expression of members of the cluster, were found in about 47% of taste buds, and could also be found in several other organs. A population of EGFP-positive cells was identified in thymic epithelial cells, in the lamina propria of the intestine and in vascular smooth muscle cells of cardiac blood vessels. EGFP-positive cells were also identified in the epithelium of organs readily exposed to pathogens including lower airways, the gastrointestinal tract, urethra, vagina, and cervix. With respect to the function of cells expressing this bitter taste receptor cluster, RNA-seq analysis in EGFP-positive cells isolated from the epithelium of trachea and stomach showed expression of genes related to innate immunity. These data further support the concept that bitter taste receptors serve functions outside the gustatory system.
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Affiliation(s)
- Shuya Liu
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Shun Lu
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Rui Xu
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Ann Atzberger
- Flow Cytometry Service Facility, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Stefan Günther
- ECCPS Bioinformatics and Deep Sequencing Platform, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Nina Wettschureck
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany.,Medical Faculty, Goethe University Frankfurt, Frankfurt, Germany
| | - Stefan Offermanns
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany.,Medical Faculty, Goethe University Frankfurt, Frankfurt, Germany
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44
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Goedicke-Fritz S, Härtel C, Krasteva-Christ G, Kopp MV, Meyer S, Zemlin M. Preterm Birth Affects the Risk of Developing Immune-Mediated Diseases. Front Immunol 2017; 8:1266. [PMID: 29062316 PMCID: PMC5640887 DOI: 10.3389/fimmu.2017.01266] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 09/22/2017] [Indexed: 12/12/2022] Open
Abstract
Prematurity affects approximately 10% of all children, resulting in drastically altered antigen exposure due to premature confrontation with microbes, nutritional antigens, and other environmental factors. During the last trimester of pregnancy, the fetal immune system adapts to tolerate maternal and self-antigens, while also preparing for postnatal immune defense by acquiring passive immunity from the mother. Since the perinatal period is regarded as the most important “window of opportunity” for imprinting metabolism and immunity, preterm birth may have long-term consequences for the development of immune-mediated diseases. Intriguingly, preterm neonates appear to develop bronchial asthma more frequently, but atopic dermatitis less frequently in comparison to term neonates. The longitudinal study of preterm neonates could offer important insights into the process of imprinting for immune-mediated diseases. On the one hand, preterm birth may interrupt influences of the intrauterine environment on the fetus that increase or decrease the risk of later immune disease (e.g., maternal antibodies and placenta-derived factors), whereas on the other hand, it may lead to the premature exposure to protective or harmful extrauterine factors such as microbiota and nutritional antigen. Solving this puzzle may help unravel new preventive and therapeutic approaches for immune diseases.
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Affiliation(s)
- Sybelle Goedicke-Fritz
- Laboratory of Neonatology and Pediatric Immunology, Department of Pediatrics, Philipps University Marburg, Marburg, Germany.,Department of General Pediatrics and Neonatology, Saarland University Medical School, Homburg, Germany
| | | | | | - Matthias V Kopp
- Department of Pediatric Allergy and Pulmonology, University of Lübeck, Airway Research-Center North (ARCN), Lübeck, Germany
| | - Sascha Meyer
- Department of General Pediatrics and Neonatology, Saarland University Medical School, Homburg, Germany
| | - Michael Zemlin
- Department of General Pediatrics and Neonatology, Saarland University Medical School, Homburg, Germany
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45
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Mennella JA, Mathew PS, Lowenthal ED. Use of Adult Sensory Panel to Study Individual Differences in the Palatability of a Pediatric HIV Treatment Drug. Clin Ther 2017; 39:2038-2048. [PMID: 28923290 PMCID: PMC5654675 DOI: 10.1016/j.clinthera.2017.08.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 07/26/2017] [Accepted: 08/23/2017] [Indexed: 01/17/2023]
Abstract
PURPOSE The recommended first-line treatment for young children infected with HIV includes the liquid formulation of the co-formulated protease inhibitors lopinavir/ritonavir (Kaletra® [Abbott Laboratories, Chicago, Illinois]). Clinical reports indicate that some children readily accept the taste of Kaletra, whereas others strongly reject it, which can deter therapeutic adherence and outcomes. METHODS As a proof-of-concept approach, a sensory panel of genotyped adults was used to document the range of individual differences in the taste and palatability (hedonics) of the liquid formulation of Kaletra and other taste stimuli, including common excipients. Panelists rated taste sensations using generalized labeled magnitude scales to determine genotype-phenotype relationships. Several months later, the panelists were retested to assess response reliability. FINDINGS Not all panelists had the same sensory experience when tasting Kaletra. Palatability ratings varied widely, from moderate like to strongest imaginable dislike, and were reliable over time. The more irritating and bitter Kaletra tasted, the more disliked by the panelist. The more they disliked the taste of Kaletra, the more they disliked the taste of its excipient ethanol and the bitter stimulus denatonium. Those who experienced less bitter and sweeter taste sensations had a different genetic signature than the other panelists. Bitterness and irritation ratings of Kaletra varied by the orphaned bitter receptor gene (TAS2R60), whereas sweetness ratings of Kaletra varied according to the cold receptor gene (TRPM8), which is activated by menthol, an excipient of Kaletra. Neither genotype related to ratings for ethanol or denatonium, however. IMPLICATIONS The use of a sensory panel holds promise as a first step in determining the nature of individual differences in the palatability of existing pediatric drug formulations and sources of variation. In this era of personalized medicine, the need is great to develop psychophysical tools to determine which drugs will show variation in acceptance by children and whether patterns of individual variation in taste as assessed by adults mirror those of young patients. ClinicalTrials.gov identifier: NCT01841710.
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Affiliation(s)
| | | | - Elizabeth D Lowenthal
- University of Pennsylvania Perelman School of Medicine, Departments of Pediatrics and Epidemiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
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46
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Bitter or not? BitterPredict, a tool for predicting taste from chemical structure. Sci Rep 2017; 7:12074. [PMID: 28935887 PMCID: PMC5608695 DOI: 10.1038/s41598-017-12359-7] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 09/07/2017] [Indexed: 11/16/2022] Open
Abstract
Bitter taste is an innately aversive taste modality that is considered to protect animals from consuming toxic compounds. Yet, bitterness is not always noxious and some bitter compounds have beneficial effects on health. Hundreds of bitter compounds were reported (and are accessible via the BitterDB http://bitterdb.agri.huji.ac.il/dbbitter.php), but numerous additional bitter molecules are still unknown. The dramatic chemical diversity of bitterants makes bitterness prediction a difficult task. Here we present a machine learning classifier, BitterPredict, which predicts whether a compound is bitter or not, based on its chemical structure. BitterDB was used as the positive set, and non-bitter molecules were gathered from literature to create the negative set. Adaptive Boosting (AdaBoost), based on decision trees machine-learning algorithm was applied to molecules that were represented using physicochemical and ADME/Tox descriptors. BitterPredict correctly classifies over 80% of the compounds in the hold-out test set, and 70–90% of the compounds in three independent external sets and in sensory test validation, providing a quick and reliable tool for classifying large sets of compounds into bitter and non-bitter groups. BitterPredict suggests that about 40% of random molecules, and a large portion (66%) of clinical and experimental drugs, and of natural products (77%) are bitter.
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47
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Risso DS, Giuliani C, Antinucci M, Morini G, Garagnani P, Tofanelli S, Luiselli D. A bio-cultural approach to the study of food choice: The contribution of taste genetics, population and culture. Appetite 2017; 114:240-247. [DOI: 10.1016/j.appet.2017.03.046] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 03/23/2017] [Accepted: 03/30/2017] [Indexed: 12/14/2022]
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48
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Abstract
The past decade has witnessed a consolidation and refinement of the extraordinary progress made in taste research. This Review describes recent advances in our understanding of taste receptors, taste buds, and the connections between taste buds and sensory afferent fibres. The article discusses new findings regarding the cellular mechanisms for detecting tastes, new data on the transmitters involved in taste processing and new studies that address longstanding arguments about taste coding.
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49
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Lack of TRPM5-Expressing Microvillous Cells in Mouse Main Olfactory Epithelium Leads to Impaired Odor-Evoked Responses and Olfactory-Guided Behavior in a Challenging Chemical Environment. eNeuro 2017. [PMID: 28612045 DOI: 10.1523/eneuro.0135‐17.2017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The mammalian main olfactory epithelium (MOE) modifies its activities in response to changes in the chemical environment. This process is essential for maintaining the functions of the olfactory system and the upper airway. However, mechanisms involved in this functional maintenance, especially those occurring via paracrine regulatory pathways within the multicellular MOE, are poorly understood. Previously, a population of non-neuronal, transient receptor potential M5-expressing microvillous cells (TRPM5-MCs) was identified in the MOE, and the initial characterization of these cells showed that they are cholinergic and responsive to various xenobiotics including odorants at high concentrations. Here, we investigated the role of TRPM5-MCs in maintaining olfactory function using transcription factor Skn-1a knockout (Skn-1a-/-) mice, which lack TRPM5-MCs in the MOE. Under our standard housing conditions, Skn-1a-/- mice do not differ significantly from control mice in odor-evoked electro-olfactogram (EOG) responses and olfactory-guided behaviors, including finding buried food and preference reactions to socially and sexually relevant odors. However, after a 2-wk exposure to high-concentration odor chemicals and chitin powder, Skn-1a-/- mice exhibited a significant reduction in their odor and pheromone-evoked EOG responses. Consequently, their olfactory-guided behaviors were impaired compared with vehicle-exposed Skn-1a-/- mice. Conversely, the chemical exposure did not induce significant changes in the EOG responses and olfactory behaviors of control mice. Therefore, our physiological and behavioral results indicate that TRPM5-MCs play a protective role in maintaining the olfactory function of the MOE.
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50
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Lack of TRPM5-Expressing Microvillous Cells in Mouse Main Olfactory Epithelium Leads to Impaired Odor-Evoked Responses and Olfactory-Guided Behavior in a Challenging Chemical Environment. eNeuro 2017; 4:eN-NWR-0135-17. [PMID: 28612045 PMCID: PMC5467397 DOI: 10.1523/eneuro.0135-17.2017] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 05/18/2017] [Accepted: 05/29/2017] [Indexed: 11/21/2022] Open
Abstract
The mammalian main olfactory epithelium (MOE) modifies its activities in response to changes in the chemical environment. This process is essential for maintaining the functions of the olfactory system and the upper airway. However, mechanisms involved in this functional maintenance, especially those occurring via paracrine regulatory pathways within the multicellular MOE, are poorly understood. Previously, a population of non-neuronal, transient receptor potential M5-expressing microvillous cells (TRPM5-MCs) was identified in the MOE, and the initial characterization of these cells showed that they are cholinergic and responsive to various xenobiotics including odorants at high concentrations. Here, we investigated the role of TRPM5-MCs in maintaining olfactory function using transcription factor Skn-1a knockout (Skn-1a-/-) mice, which lack TRPM5-MCs in the MOE. Under our standard housing conditions, Skn-1a-/- mice do not differ significantly from control mice in odor-evoked electro-olfactogram (EOG) responses and olfactory-guided behaviors, including finding buried food and preference reactions to socially and sexually relevant odors. However, after a 2-wk exposure to high-concentration odor chemicals and chitin powder, Skn-1a-/- mice exhibited a significant reduction in their odor and pheromone-evoked EOG responses. Consequently, their olfactory-guided behaviors were impaired compared with vehicle-exposed Skn-1a-/- mice. Conversely, the chemical exposure did not induce significant changes in the EOG responses and olfactory behaviors of control mice. Therefore, our physiological and behavioral results indicate that TRPM5-MCs play a protective role in maintaining the olfactory function of the MOE.
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