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Melis M, Errigo A, Crnjar R, Pes GM, Tomassini Barbarossa I. TAS2R38 bitter taste receptor and attainment of exceptional longevity. Sci Rep 2019; 9:18047. [PMID: 31792278 PMCID: PMC6889489 DOI: 10.1038/s41598-019-54604-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 11/12/2019] [Indexed: 12/18/2022] Open
Abstract
Bitter taste receptors play crucial roles in detecting bitter compounds not only in the oral cavity, but also in extraoral tissues where they are involved in a variety of non‒tasting physiological processes. On the other hand, disorders or modifications in the sensitivity or expression of these extraoral receptors can affect physiological functions. Here we evaluated the role of the bitter receptor TAS2R38 in attainment of longevity, since it has been widely associated with individual differences in taste perception, food preferences, diet, nutrition, immune responses and pathophysiological mechanisms. Differences in genotype distribution and haplotype frequency at the TAS2R38 gene between a cohort of centenarian and near-centenarian subjects and two control cohorts were determined. Results show in the centenarian cohort an increased frequency of subjects carrying the homozygous genotype for the functional variant of TAS2R38 (PAV/PAV) and a decreased frequency of those having homozygous genotype for the non-functional form (AVI/AVI), as compared to those determined in the two control cohorts. In conclusion, our data providing evidence of an association between genetic variants of TAS2R38 gene and human longevity, suggest that TAS2R38 bitter receptor can be involved in the molecular physiological mechanisms implied in the biological process of aging.
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Affiliation(s)
- Melania Melis
- Department of Biomedical Sciences, University of Cagliari, Monserrato, CA, 09042, Italy.
| | - Alessandra Errigo
- Department of Biomedical Sciences, University of Sassari, Sassari, SS, 07100, Italy
| | - Roberto Crnjar
- Department of Biomedical Sciences, University of Cagliari, Monserrato, CA, 09042, Italy
| | - Giovanni Mario Pes
- Department of Medical, Surgical and Experimental Sciences, University of Sassari, Sassari, SS, 07100, Italy.,Sardinia Longevity Blue Zone Observatory, Ogliastra, Italy
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Douglas JE, Lin C, Mansfield CJ, Arayata CJ, Cowart BJ, Spielman AI, Adappa ND, Palmer JN, Cohen NA, Reed DR. Tissue-Dependent Expression of Bitter Receptor TAS2R38 mRNA. Chem Senses 2019; 44:33-40. [PMID: 30351347 DOI: 10.1093/chemse/bjy066] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
TAS2R38 is a human bitter receptor gene with a common but inactive allele; people homozygous for the inactive form cannot perceive low concentrations of certain bitter compounds. The frequency of the inactive and active forms of this receptor is nearly equal in many human populations, and heterozygotes with 1 copy of the active form and 1 copy of the inactive form have the most common diplotype. However, even though they have the same genotype, heterozygotes differ markedly in their perception of bitterness, perhaps in part because of differences in TAS2R38 mRNA expression. Other tissues express this receptor too, including the nasal sinuses, where it contributes to pathogen defense. We, therefore, wondered whether heterozygous people had a similar wide range of TAS2R38 mRNA in sinonasal tissue and whether those with higher TAS2R38 mRNA expression in taste tissue were similarly high expressers in nasal tissue. To that end, we measured gene expression by quantitative PCR in taste and sinonasal tissue and found that expression abundance in one tissue was not related to the other. We confirmed the independence of expression in other tissue pairs expressing TAS2R38 mRNA, such as pancreas and small intestine, using autopsy data from the Genotype-Tissue Expression project (although people with high expression of TAS2R38 mRNA in colon also tended to have higher expression in the small intestine). Thus, taste tissue TAS2R38 mRNA expression among heterozygotes is unlikely to predict expression in other tissues, perhaps reflecting tissue-dependent function, and hence regulation, of this protein.
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Affiliation(s)
- Jennifer E Douglas
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA, USA.,Monell Chemical Senses Center, Philadelphia, PA, USA
| | - Cailu Lin
- Monell Chemical Senses Center, Philadelphia, PA, USA
| | | | | | | | - Andrew I Spielman
- Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, NY, USA
| | - Nithin D Adappa
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | - James N Palmer
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Noam A Cohen
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA, USA.,Monell Chemical Senses Center, Philadelphia, PA, USA.,Philadelphia Veterans Affairs Medical Center Surgical Services, Philadelphia, PA, USA
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53
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Carey RM, Lee RJ. Taste Receptors in Upper Airway Innate Immunity. Nutrients 2019; 11:nu11092017. [PMID: 31466230 PMCID: PMC6770031 DOI: 10.3390/nu11092017] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 08/19/2019] [Accepted: 08/22/2019] [Indexed: 02/07/2023] Open
Abstract
Taste receptors, first identified on the tongue, are best known for their role in guiding our dietary preferences. The expression of taste receptors for umami, sweet, and bitter have been demonstrated in tissues outside of the oral cavity, including in the airway, brain, gastrointestinal tract, and reproductive organs. The extra-oral taste receptor chemosensory pathways and the endogenous taste receptor ligands are generally unknown, but there is increasing data suggesting that taste receptors are involved in regulating some aspects of innate immunity, and may potentially control the composition of the nasal microbiome in healthy individuals or patients with upper respiratory diseases like chronic rhinosinusitis (CRS). For this reason, taste receptors may serve as potential therapeutic targets, providing alternatives to conventional antibiotics. This review focuses on the physiology of sweet (T1R) and bitter (T2R) taste receptors in the airway and their activation by secreted bacterial products. There is particular focus on T2R38 in sinonasal ciliated cells, as well as the sweet and bitter receptors found on specialized sinonasal solitary chemosensory cells. Additionally, this review explores the impact of genetic variations in these receptors on the differential susceptibility of patients to upper airway infections, such as CRS.
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Affiliation(s)
- Ryan M Carey
- Department of Otorhinolaryngology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Robert J Lee
- Department of Otorhinolaryngology and Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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Wynne M, Atkinson C, Schlosser RJ, Mulligan JK. Contribution of Epithelial Cell Dysfunction to the Pathogenesis of Chronic Rhinosinusitis with Nasal Polyps. Am J Rhinol Allergy 2019; 33:782-790. [PMID: 31382760 DOI: 10.1177/1945892419868588] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Background In the past, the airway epithelium was thought to be primarily an inert physical barrier. We now know that the upper airway epithelium plays a critical role in both innate and adaptive immunity, and that epithelial dysfunction is strongly associated with inflammatory airway disease. The pathogenesis of chronic rhinosinusitis is poorly understood, but growing evidence supports a key role for the airway epithelium in the pathophysiology of the disease. Objective The purpose of this study is to explore our current understanding of how dysfunction in human sinonasal epithelial cells (HSNECs) contributes to the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP) and to examine how current and developing therapies affect epithelial cell functions. Methods A literature review of papers published in English pertaining to epithelial cell dysfunction in patients with CRSwNP was performed using the PubMed database. The search utilized combinations of the following key words: sinusitis, polyps, epithelium, pathophysiology, barrier function, dendritic cells, eosinophils, T cells, complement, mucociliary clearance, vitamin D, cytokines, chemokines, taste receptors, steroids, saline, and therapy. Results HSNEC mucociliary clearance, barrier function, secretion of cytokines, influence on dendritic cells, influence on T-cells, regulation of eosinophils, vitamin D metabolism, complement production, and taste receptor function are altered in patients with CRSwNP and contribute to the pathogenesis of the disease. Current therapies utilized to manage CRSwNP counteract the effects of HSNEC dysfunction and relieve key symptoms of the disease. Conclusion HSNECs are key players in both innate and adaptive immunity, and altered epithelial functions are closely intertwined with the pathogenesis of CRSwNP. Our review supports further investigation of altered HSNEC function in patients with CRSwNP and supports development of novel epithelial-targeted therapies for its management.
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Affiliation(s)
- Michael Wynne
- Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, South Carolina
| | - Carl Atkinson
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, South Carolina.,Department of Surgery, Medical University of South Carolina, Lee Patterson Allen Transplant Immunobiology Laboratory, Charleston, South Carolina
| | - Rodney J Schlosser
- Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, South Carolina
| | - Jennifer K Mulligan
- Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, South Carolina.,Department of Pediatrics, Medical University of South Carolina, Charleston, South Carolina
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Triantafillou V, Workman AD, Patel NN, Maina IW, Tong CCL, Kuan EC, Kennedy DW, Palmer JN, Adappa ND, Waizel-Haiat S, Cohen NA. Broncho-Vaxom® (OM-85 BV) soluble components stimulate sinonasal innate immunity. Int Forum Allergy Rhinol 2019; 9:370-377. [PMID: 30615298 DOI: 10.1002/alr.22276] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Revised: 11/01/2018] [Accepted: 12/12/2018] [Indexed: 01/29/2023]
Abstract
BACKGROUND Broncho-Vaxom® (OM-85 BV) is an extract of infectious respiratory bacteria that is used as an immunostimulant outside of the United States for the prevention and treatment of bronchitis and rhinosinusitis. Prior studies have shown that use of OM-85 BV is associated with reduction in frequency of respiratory infection and decreased duration of antibiotic usage. However, the effects of OM-85 BV on respiratory mucosal innate immunity are unknown. METHODS Human sinonasal epithelial cells were grown at an air-liquid interface (ALI). Ciliary beat frequency (CBF) and nitric oxide (NO) production in response to stimulation with OM-85 BV was measured in vitro. Pharmacologic inhibitors of bitter taste receptor (T2R) signaling were used to determine if this pathway was taste-receptor-mediated. RESULTS Apical application of OM-85 BV resulted in an NO-mediated increase in CBF (p < 0.05) and increased NO production (p < 0.0001) when compared to saline-stimulated control cultures. ALI pretreatment with taste receptor pathway inhibitors blocked OM-85 BV-induced increases in NO. CONCLUSION OM-85 BV has ciliostimulatory and immunogenic properties that may be partially responsible for its observed efficacy as a respiratory therapeutic. These responses were NO-dependent and consistent with T2R activation. Further work is necessary to elucidate specific component-receptor signaling relationships.
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Affiliation(s)
- Vasiliki Triantafillou
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA
| | - Alan D Workman
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA
| | - Neil N Patel
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA
| | - Ivy W Maina
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA
| | - Charles C L Tong
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA
| | - Edward C Kuan
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of California, Irvine (UCI), Irvine, CA
| | - David W Kennedy
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA
| | - James N Palmer
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA
| | - Nithin D Adappa
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA
| | - Salomon Waizel-Haiat
- Smell and Taste Clinic, Centro Neurológico ABC, Centro Médico ABC, Ciudad de México, Mexico City, Mexico
| | - Noam A Cohen
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA.,Corporal Michael J. Crescenz Veterans Administration Medical Center, Philadelphia, PA.,Monell Chemical Senses Center, Philadelphia, PA
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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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57
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Earl JP, Adappa ND, Krol J, Bhat AS, Balashov S, Ehrlich RL, Palmer JN, Workman AD, Blasetti M, Sen B, Hammond J, Cohen NA, Ehrlich GD, Mell JC. Species-level bacterial community profiling of the healthy sinonasal microbiome using Pacific Biosciences sequencing of full-length 16S rRNA genes. MICROBIOME 2018; 6:190. [PMID: 30352611 PMCID: PMC6199724 DOI: 10.1186/s40168-018-0569-2] [Citation(s) in RCA: 92] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 10/02/2018] [Indexed: 05/03/2023]
Abstract
BACKGROUND Pan-bacterial 16S rRNA microbiome surveys performed with massively parallel DNA sequencing technologies have transformed community microbiological studies. Current 16S profiling methods, however, fail to provide sufficient taxonomic resolution and accuracy to adequately perform species-level associative studies for specific conditions. This is due to the amplification and sequencing of only short 16S rRNA gene regions, typically providing for only family- or genus-level taxonomy. Moreover, sequencing errors often inflate the number of taxa present. Pacific Biosciences' (PacBio's) long-read technology in particular suffers from high error rates per base. Herein, we present a microbiome analysis pipeline that takes advantage of PacBio circular consensus sequencing (CCS) technology to sequence and error correct full-length bacterial 16S rRNA genes, which provides high-fidelity species-level microbiome data. RESULTS Analysis of a mock community with 20 bacterial species demonstrated 100% specificity and sensitivity with regard to taxonomic classification. Examination of a 250-plus species mock community demonstrated correct species-level classification of > 90% of taxa, and relative abundances were accurately captured. The majority of the remaining taxa were demonstrated to be multiply, incorrectly, or incompletely classified. Using this methodology, we examined the microgeographic variation present among the microbiomes of six sinonasal sites, by both swab and biopsy, from the anterior nasal cavity to the sphenoid sinus from 12 subjects undergoing trans-sphenoidal hypophysectomy. We found greater variation among subjects than among sites within a subject, although significant within-individual differences were also observed. Propiniobacterium acnes (recently renamed Cutibacterium acnes) was the predominant species throughout, but was found at distinct relative abundances by site. CONCLUSIONS Our microbial composition analysis pipeline for single-molecule real-time 16S rRNA gene sequencing (MCSMRT, https://github.com/jpearl01/mcsmrt ) overcomes deficits of standard marker gene-based microbiome analyses by using CCS of entire 16S rRNA genes to provide increased taxonomic and phylogenetic resolution. Extensions of this approach to other marker genes could help refine taxonomic assignments of microbial species and improve reference databases, as well as strengthen the specificity of associations between microbial communities and dysbiotic states.
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Affiliation(s)
- Joshua P. Earl
- Department of Microbiology & Immunology, Centers for Genomic Sciences and Advanced Microbial Processing, Drexel University College of Medicine, 245 N 15th Street, Philadelphia, PA 19102 USA
| | - Nithin D. Adappa
- Veteran’s Administration Medical Center, Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, 3400 Spruce Street, 5 Ravdin, Philadelphia, PA 19104-4283 USA
| | - Jaroslaw Krol
- Department of Microbiology & Immunology, Centers for Genomic Sciences and Advanced Microbial Processing, Drexel University College of Medicine, 245 N 15th Street, Philadelphia, PA 19102 USA
| | - Archana S. Bhat
- Department of Microbiology & Immunology, Centers for Genomic Sciences and Advanced Microbial Processing, Drexel University College of Medicine, 245 N 15th Street, Philadelphia, PA 19102 USA
| | - Sergey Balashov
- Department of Microbiology & Immunology, Centers for Genomic Sciences and Advanced Microbial Processing, Drexel University College of Medicine, 245 N 15th Street, Philadelphia, PA 19102 USA
| | - Rachel L. Ehrlich
- Department of Microbiology & Immunology, Centers for Genomic Sciences and Advanced Microbial Processing, Drexel University College of Medicine, 245 N 15th Street, Philadelphia, PA 19102 USA
| | - James N. Palmer
- Veteran’s Administration Medical Center, Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, 3400 Spruce Street, 5 Ravdin, Philadelphia, PA 19104-4283 USA
| | - Alan D. Workman
- Veteran’s Administration Medical Center, Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, 3400 Spruce Street, 5 Ravdin, Philadelphia, PA 19104-4283 USA
| | - Mariel Blasetti
- Veteran’s Administration Medical Center, Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, 3400 Spruce Street, 5 Ravdin, Philadelphia, PA 19104-4283 USA
| | - Bhaswati Sen
- Department of Microbiology & Immunology, Centers for Genomic Sciences and Advanced Microbial Processing, Drexel University College of Medicine, 245 N 15th Street, Philadelphia, PA 19102 USA
| | - Jocelyn Hammond
- Department of Microbiology & Immunology, Centers for Genomic Sciences and Advanced Microbial Processing, Drexel University College of Medicine, 245 N 15th Street, Philadelphia, PA 19102 USA
| | - Noam A. Cohen
- Veteran’s Administration Medical Center, Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, 3400 Spruce Street, 5 Ravdin, Philadelphia, PA 19104-4283 USA
| | - Garth D. Ehrlich
- Department of Microbiology & Immunology, Centers for Genomic Sciences and Advanced Microbial Processing, Drexel University College of Medicine, 245 N 15th Street, Philadelphia, PA 19102 USA
| | - Joshua Chang Mell
- Department of Microbiology & Immunology, Centers for Genomic Sciences and Advanced Microbial Processing, Drexel University College of Medicine, 245 N 15th Street, Philadelphia, PA 19102 USA
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Role of Taste Receptors as Sentinels of Innate Immunity in the Upper Airway. J Pathog 2018; 2018:9541987. [PMID: 30363975 PMCID: PMC6188595 DOI: 10.1155/2018/9541987] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 08/01/2018] [Accepted: 08/27/2018] [Indexed: 12/21/2022] Open
Abstract
Evidence is emerging that shows taste receptors serve functions outside of taste sensation of the tongue. Taste receptors have been found in tissue across the human body, including the gastrointestinal tract, bladder, brain, and airway. These extraoral taste receptors appear to be important in modulating the innate immune response through detection of pathogens. This review discusses taste receptor signaling, focusing on the G-protein-coupled receptors that detect bitter and sweet compounds in the upper airway epithelium. Emphasis is given to recent studies which link the physiology of sinonasal taste receptors to clinical manifestation of upper airway disease.
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Workman AD, Kohanski MA, Cohen NA. Biomarkers in Chronic Rhinosinusitis with Nasal Polyps. Immunol Allergy Clin North Am 2018; 38:679-692. [PMID: 30342588 DOI: 10.1016/j.iac.2018.06.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Chronic rhinosinusitis is a complex disease that exists along the inflammatory spectrum between types 1 and 2 inflammation. The classic phenotypic differentiation of chronic rhinosinusitis based on the presence or absence of inflammatory polyps remains one of the best differentiators of response to therapy. Development of biologics for the treatment of atopic disease and asthma and topical therapies for sinusitis have placed renewed emphasis on understanding the pathophysiology of polyp disease. Identification of key markers of polyposis will allow for better stratification of inflammatory polyp disease endotypes to objectively identify medical therapies and track response to treatment.
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Affiliation(s)
- Alan D Workman
- Department of Otorhinolaryngology-Head and Neck Surgery, Division of Rhinology, University of Pennsylvania, Perelman School of Medicine, 3400 Spruce Street, Philadelphia, PA 19104, USA
| | - Michael A Kohanski
- Department of Otorhinolaryngology-Head and Neck Surgery, Division of Rhinology, University of Pennsylvania, Perelman School of Medicine, 3400 Spruce Street, Philadelphia, PA 19104, USA
| | - Noam A Cohen
- Department of Otorhinolaryngology-Head and Neck Surgery, Division of Rhinology, University of Pennsylvania, Perelman School of Medicine, 3400 Spruce Street, Philadelphia, PA 19104, USA; Philadelphia Veterans Affairs Medical Center, 3900 Woodland Avenue, Philadelphia, PA 19104, USA; Monell Chemical Senses Center, 3500 Market Street, Philadelphia, PA 19104, USA.
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Interactions between Bitter Taste, Diet and Dysbiosis: Consequences for Appetite and Obesity. Nutrients 2018; 10:nu10101336. [PMID: 30241292 PMCID: PMC6213475 DOI: 10.3390/nu10101336] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 09/18/2018] [Accepted: 09/19/2018] [Indexed: 12/19/2022] Open
Abstract
The type 2 family of taste receptors (T2Rs) detect and respond to bitter tastants. These receptors are expressed throughout the gastrointestinal (GI) tract, with location dependant roles. In the oral cavity, T2Rs are involved in the conscious perception of bitter tastants, while in the lower GI tract they have roles in chemoreception and regulation of GI function. Through these diverse roles, these receptors may be involved in modulating appetite and diet, with consequences for weight regulation and obesity. Interestingly, the concentration of T2Rs in the GI tract is greatest in the large intestine, the organ with the densest colonisation of bacteria. The gut microbiome has been the subject of intense research, as a plethora of roles linking microbiota to human health continue to be uncovered. Of particular interest is the microbial signature associated with obesity. Obesity is a leading health concern, and advances in our understanding of this disease are needed. Diet is a known modifiable factor in the development of obesity. However, diet only partially explains disease risk. Changes in microbial energy harvesting by the microbiota plays a role in obesity, and the composition of these energy harvesting populations may be controlled by taste receptors. This review explores T2Rs as a potential link between obesity and the human GI microbiome.
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Maina IW, Workman AD, Cohen NA. The role of bitter and sweet taste receptors in upper airway innate immunity: Recent advances and future directions. World J Otorhinolaryngol Head Neck Surg 2018; 4:200-208. [PMID: 30506052 PMCID: PMC6251955 DOI: 10.1016/j.wjorl.2018.07.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 07/18/2018] [Indexed: 01/02/2023] Open
Abstract
Bitter (T2R) and sweet (T1R) taste receptors have been implicated in sinonasal innate immunity and in the pathophysiology of chronic rhinosinusitis (CRS). Taste receptors are expressed on several sinonasal cell types including ciliated epithelial cells and solitary chemosensory cells. Bitter agonists released by pathogenic microbes elicit a T2R dependent signaling cascade which induces the release of bactericidal nitric oxide, increases mucociliary clearance, and promotes secretion of antimicrobial peptides. Genetic variation conferred by polymorphisms in T2R related genes is associated with differential CRS susceptibility, symptomatology and post-treatment outcomes. More recently, based on our understanding of T1R and T2R function, investigators have discovered novel potential therapeutics in T2R agonists and T1R antagonists. This review will discuss bitter and sweet taste receptor function in sinonasal immunity, explore the emerging diagnostic and therapeutic implications stemming from the most recent findings, and suggest directions for future research.
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Affiliation(s)
- Ivy W Maina
- Department of Otorhinolaryngology-Head and Neck Surgery, Division of Rhinology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Alan D Workman
- Department of Otorhinolaryngology-Head and Neck Surgery, Division of Rhinology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Noam A Cohen
- Department of Otorhinolaryngology-Head and Neck Surgery, Division of Rhinology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.,Corporal Michael J. Crescenz Veterans Administration Medical Center, Philadelphia, PA, 19104, USA.,Monell Chemical Senses Center, Philadelphia, PA, 19104, USA
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62
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Abstract
PURPOSE OF REVIEW To perform analysis of evidence in current literature on the topic of genetics and chronic rhinosinusitis (CRS), with a particular focus on recent findings in the cystic fibrosis transmembrane regulator (CFTR), genes associated with primary ciliary dyskinesia, and taste receptor T2R38. Other genes that have been found to have association with CRS are also presented and discussed. RECENT FINDINGS Recent studies in CFTR and CRS research have investigated possible CFTR-potentiators for treatment of refractory CRS. The T2R38 gene has been shown to be applicable in the clinical setting with a testable phenotype and may have a role in the prognosis and influencing management strategies of CRS patients. Many genes of the immune system have been studied, with genome-wide association studies and candidate-gene approaches identifying new associations that will need replication and further elucidation. SUMMARY CRS is a multifactorial disease, with strong evidence of a genetic component in its pathophysiology for some cases. Currently, there are over 70 genes that have been genetically associated with CRS in the past 15 years. Future investigations into genetic causes and predispositions of CRS may allow for improved prognostication and development of disease-prevention strategies as well as novel therapeutic targets.
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63
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Rowan NR, Soler ZM, Othieno F, Storck KA, Smith TL, Schlosser RJ. Impact of bitter taste receptor phenotype upon clinical presentation in chronic rhinosinusitis. Int Forum Allergy Rhinol 2018; 8:1013-1020. [PMID: 29972727 DOI: 10.1002/alr.22138] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 03/25/2018] [Accepted: 04/10/2018] [Indexed: 12/21/2022]
Abstract
BACKGROUND Genetic variation of the bitter taste receptor T2R38 has been associated with recalcitrant chronic rhinosinusitis (CRS). Specific T2R38 polymorphisms, correlating with bitter taste sensitivity to phenylthiocarbamide (PTC), have been identified as an independent risk factor for surgical intervention in CRS patients without polyps; however, the exact role of PTC tasting ability in clinical practice remains unknown. In this investigation we characterize PTC taste sensitivity in a tertiary care rhinology practice with pertinent clinical measures of disease and quality of life (QOL). METHODS Adult CRS patients were prospectively assessed for their ability to taste PTC and categorized as nontasters, tasters, or supertasters. Objective taste was assessed with strips for bitter, sweet, sour, and salty, whereas olfactory testing was measured with Sniffin' Sticks. Correlation was performed between PTC tasting ability and patient demographics, endoscopy scores, validated QOL surveys, and both subjective and objective measures of taste and olfaction. RESULTS Sixty-seven patients were enrolled. Fifty-two percent were identified as nontasters, 34% as tasters, and 13% as supertasters. Nontasters were more likely to be non-Hispanic (p = 0.018), white (p = 0.027), without nasal polyposis (p = 0.004), and nonasthmatics (p = 0.019). There were no other statistical differences in patients' demographics, QOL measures, and subjective or objective olfactory and taste scores when compared with patients' oral PTC-sensing ability. CONCLUSION Oral PTC-sensing ability may serve as a convenient marker of increased disease severity in white CRS patients without polyps and vary among regional populations. PTC tasting ability appears to provide unique phenotypic information not obtained using other subjective or objective measures of smell and taste.
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Affiliation(s)
- Nicholas R Rowan
- Division of Rhinology and Sinus Surgery, Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, SC
| | - Zachary M Soler
- Division of Rhinology and Sinus Surgery, Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, SC
| | - Florence Othieno
- Division of Rhinology and Sinus Surgery, Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, SC
| | - Kristina A Storck
- Division of Rhinology and Sinus Surgery, Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, SC
| | - Timothy L Smith
- Oregon Health & Science University, Department of Otolaryngology-Head and Neck Surgery, Division of Rhinology and Sinus/Skull Base Surgery, Portland, OR
| | - Rodney J Schlosser
- Division of Rhinology and Sinus Surgery, Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, SC.,Department of Surgery, Ralph H. Johnson VA Medical Center, Charleston, SC
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The Role of Taste Receptors in Airway Innate Immune Defense. SINUSITIS 2018. [DOI: 10.3390/sinusitis3020006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Freund JR, Mansfield CJ, Doghramji LJ, Adappa ND, Palmer JN, Kennedy DW, Reed DR, Jiang P, Lee RJ. Activation of airway epithelial bitter taste receptors by Pseudomonas aeruginosa quinolones modulates calcium, cyclic-AMP, and nitric oxide signaling. J Biol Chem 2018; 293:9824-9840. [PMID: 29748385 DOI: 10.1074/jbc.ra117.001005] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2017] [Revised: 04/17/2018] [Indexed: 12/12/2022] Open
Abstract
Bitter taste receptors (taste family 2 bitter receptor proteins; T2Rs), discovered in many tissues outside the tongue, have recently become potential therapeutic targets. We have shown previously that airway epithelial cells express several T2Rs that activate innate immune responses that may be important for treatment of airway diseases such as chronic rhinosinusitis. It is imperative to more clearly understand what compounds activate airway T2Rs as well as their full range of functions. T2R isoforms in airway motile cilia (T2R4, -14, -16, and -38) produce bactericidal levels of nitric oxide (NO) that also increase ciliary beating, promoting clearance of mucus and trapped pathogens. Bacterial quorum-sensing acyl-homoserine lactones activate T2Rs and stimulate these responses in primary airway cells. Quinolones are another type of quorum-sensing molecule used by Pseudomonas aeruginosa To elucidate whether bacterial quinolones activate airway T2Rs, we analyzed calcium, cAMP, and NO dynamics using a combination of fluorescent indicator dyes and FRET-based protein biosensors. T2R-transfected HEK293T cells, several lung epithelial cell lines, and primary sinonasal cells grown and differentiated at the air-liquid interface were tested with 2-heptyl-3-hydroxy-4-quinolone (known as Pseudomonas quinolone signal; PQS), 2,4-dihydroxyquinolone, and 4-hydroxy-2-heptylquinolone (HHQ). In HEK293T cells, PQS activated T2R4, -16, and -38, whereas HHQ activated T2R14. 2,4-Dihydroxyquinolone had no effect. PQS and HHQ increased calcium and decreased both baseline and stimulated cAMP levels in cultured and primary airway cells. In primary cells, PQS and HHQ activated levels of NO synthesis previously shown to be bactericidal. This study suggests that airway T2R-mediated immune responses are activated by bacterial quinolones as well as acyl-homoserine lactones.
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Affiliation(s)
- Jenna R Freund
- From the Departments of Otorhinolaryngology-Head and Neck Surgery and
| | | | | | - Nithin D Adappa
- From the Departments of Otorhinolaryngology-Head and Neck Surgery and
| | - James N Palmer
- From the Departments of Otorhinolaryngology-Head and Neck Surgery and
| | - David W Kennedy
- From the Departments of Otorhinolaryngology-Head and Neck Surgery and
| | - Danielle R Reed
- the Monell Chemical Senses Center, Philadelphia, Pennsylvania 19104
| | - Peihua Jiang
- the Monell Chemical Senses Center, Philadelphia, Pennsylvania 19104
| | - Robert J Lee
- From the Departments of Otorhinolaryngology-Head and Neck Surgery and .,Physiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104 and
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66
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Carey RM, Workman AD, Yan CH, Chen B, Adappa ND, Palmer JN, Kennedy DW, Lee RJ, Cohen NA. Sinonasal T2R-mediated nitric oxide production in response to Bacillus cereus. Am J Rhinol Allergy 2018; 31:211-215. [PMID: 28716170 DOI: 10.2500/ajra.2017.31.4453] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Upper airway epithelial cells produce bactericidal nitric oxide (NO) in response to both gram-positive and gram-negative bacteria. Our previous work demonstrated that T2R38, a bitter taste receptor (T2R) expressed in airway epithelium, produces NO in response to quorum-sensing molecules secreted by Pseudomonas aeruginosa. We also demonstrated that Staphylococci products elicit an NO response when using a T2R-independent pathway. When screening additional human pathogens for epithelial T2R activation, we found that the gram-positive aerobe Bacillus cereus secretes a T2R agonist that yields NO production. OBJECTIVE The objective of this study was to characterize the activating B. cereus product(s) and to describe the epithelial cell signaling pathway involved. METHODS Sinonasal air-liquid interface cultures were treated with B. cereus conditioned medium (CM), and NO production was measured by using 4-amino-5-methylamino-2',7'-difluorofluorescein fluorescence imaging. Ciliary beat frequency (CBF) was assessed in response to B. cereus CM. Pharmacologic studies that use inhibitors of the T2R-signaling pathway were used to determine if the production of NO was mediated by a T2R. Purification studies were performed to analyze the physical properties of the activating product(s) contained in the CM. RESULTS A product(s) secreted by B. cereus induced NO production and increased CBF. The response varied markedly between individual patients and involved two important components of bitter taste signaling, phospholipase C isoform β-2 and the transient receptor potential melastatin isoform 5 ion channel. CONCLUSIONS This study demonstrated that a B. cereus product(s) elicited an NO-mediated innate defense response in upper airway epithelium that seemed to be partially mediated by a T2R signaling pathway. The active product that elicited the NO response was likely a small nonpeptide compound, but further purification is required for identification. Patient variation in the NO response to B. cereus products could potentially be due to genetic differences in T2Rs.
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Affiliation(s)
- Ryan M Carey
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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67
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Workman AD, Maina IW, Brooks SG, Kohanski MA, Cowart BJ, Mansfield C, Kennedy DW, Palmer JN, Adappa ND, Reed DR, Lee RJ, Cohen NA. The Role of Quinine-Responsive Taste Receptor Family 2 in Airway Immune Defense and Chronic Rhinosinusitis. Front Immunol 2018; 9:624. [PMID: 29643854 PMCID: PMC5882797 DOI: 10.3389/fimmu.2018.00624] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Accepted: 03/13/2018] [Indexed: 11/17/2022] Open
Abstract
Background Bitter (T2R) and sweet (T1R) taste receptors in the airway are important in innate immune defense, and variations in taste receptor functionality in one T2R (T2R38) correlate with disease status and disease severity in chronic rhinosinusitis (CRS). Quinine is a bitter compound that is an agonist for several T2Rs also expressed on sinonasal cells, but not for T2R38. Because of this property, quinine may stimulate innate immune defense mechanisms in the airway, and functional differences in quinine perception may be reflective of disease status in CRS. Methods Demographic and taste intensity data were collected prospectively from CRS patients and non-CRS control subjects. Sinonasal tissue from patients undergoing rhinologic surgery was also collected and grown at an air–liquid interface (ALI). Nitric oxide (NO) production and dynamic regulation of ciliary beat frequency in response to quinine stimulation were assessed in vitro. Results Quinine reliably increased ciliary beat frequency and NO production in ALI cultures in a manner consistent with T2R activation (p < 0.01). Quinine taste intensity rating was performed in 328 CRS patients and 287 control subjects demonstrating that CRS with nasal polyps (CRSwNP) patients rated quinine as significantly less intense than did control subjects. Conclusion Quinine stimulates airway innate immune defenses by increasing ciliary beat frequency and stimulating NO production in a manner fitting with T2R activation. Patient variability in quinine sensitivity is observed in taste intensity ratings, and gustatory quinine “insensitivity” is associated with CRSwNP status. Thus, taste tests for quinine may be a biomarker for CRSwNP, and topical quinine has therapeutic potential as a stimulant of innate defenses.
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Affiliation(s)
- Alan D Workman
- Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA, United States
| | - Ivy W Maina
- Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA, United States
| | - Steven G Brooks
- Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA, United States
| | - Michael A Kohanski
- Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA, United States
| | | | | | - David W Kennedy
- Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA, United States
| | - James N Palmer
- Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA, United States
| | - Nithin D Adappa
- Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA, United States
| | - Danielle R Reed
- Monell Chemical Senses Center, Philadelphia, PA, United States
| | - Robert J Lee
- Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA, United States.,Department of Physiology, University of Pennsylvania, Philadelphia, PA, United States
| | - Noam A Cohen
- Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA, United States.,Monell Chemical Senses Center, Philadelphia, PA, United States.,Philadelphia Veterans Affairs Medical Center, Philadelphia, PA, United States
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Cantone E, Negri R, Roscetto E, Grassia R, Catania MR, Capasso P, Maffei M, Soriano AA, Leone CA, Iengo M, Greco L. In Vivo Biofilm Formation, Gram-Negative Infections and TAS2R38 Polymorphisms in CRSw NP Patients. Laryngoscope 2018; 128:E339-E345. [PMID: 29570813 DOI: 10.1002/lary.27175] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 01/22/2018] [Accepted: 02/12/2018] [Indexed: 01/11/2023]
Abstract
OBJECTIVES Among the predisposing factors implicated in the immune response to airway bacterial infections, genetic variations of the bitter taste receptor TAS2R38, which is expressed in the cilia of the human sinonasal epithelial cells, seem to be associated with susceptibility to chronic rhinosinusitis (CRS) and in vitro biofilm formation. Polymorphisms in TAS2R38 generate two common haplotypes: the nonfunctional AVI (Alanine, Valine, Isoleucine) and the functional PAV (Proline, Alanine, Valine) alleles, with the latter protecting against gram-negative sinonasal infections. The aim of this study is to investigate for the first time the relevance of TAS2R38 genetic variants in the susceptibility to bacterial infections associated with in vivo biofilm formation in chronic rhinosinusitis with nasal polyps (CRSwNP) patients. STUDY DESIGN A prospective study on 100 adult patients undergoing functional endoscopic sinus surgery (FESS) for CRSwNP. METHODS Propylthiouracile (PROP) testing and TAS2R38 genotyping were applied to characterize patients for receptor functionality. Sinonasal mucosa samples were processed for microbiological examination and biofilm detection. RESULTS The nonfunctional genotype is more frequent among CRS patients than in the general population (25% vs. 18.4%, P = 0.034). Airway gram-negative infections are primarily associated with the AVI haplotype (88.9% vs. 11.1% PAV/PAV-functional genotype, P = 0.023). Biofilm formation is prevalent in CRS patients with the AVI nontaster phenotype (62.5% vs. 33.3% PAV taster or supertaster phenotype, P = 0.05). CONCLUSION Our findings confirm an inverse correlation between TAS2R38 functionality and gram-negative infections in Italian patients with CRSwNP. In addition, for the first time we demonstrated a relationship between in vivo microbial biofilm and TAS2R38 receptor variants. LEVEL OF EVIDENCE 2b. Laryngoscope, 128:E339-E345, 2018.
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Affiliation(s)
| | - Rossella Negri
- Department of Translational Medical Science (DISMET), Section of Pediatrics
| | - Emanuela Roscetto
- Department of Molecular Medicine and Medical Biotechnology, Section of Clinical Microbiology, University of Naples "Federico II"
| | - Rossella Grassia
- Department of Otolaryngology Head-Neck Surgery, Monaldi-Ospedale dei Colli, Naples, Italy
| | - Maria Rosaria Catania
- Department of Molecular Medicine and Medical Biotechnology, Section of Clinical Microbiology, University of Naples "Federico II"
| | - Pasquale Capasso
- Department of Otolaryngology Head-Neck Surgery, Monaldi-Ospedale dei Colli, Naples, Italy
| | - Marianna Maffei
- Department of Otolaryngology Head-Neck Surgery, Monaldi-Ospedale dei Colli, Naples, Italy
| | - Amata Amy Soriano
- Department of Molecular Medicine and Medical Biotechnology, Section of Clinical Microbiology, University of Naples "Federico II"
| | - Carlo Antonio Leone
- Department of Otolaryngology Head-Neck Surgery, Monaldi-Ospedale dei Colli, Naples, Italy
| | | | - Luigi Greco
- Department of Translational Medical Science (DISMET), Section of Pediatrics
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69
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Freund JR, Lee RJ. Taste receptors in the upper airway. World J Otorhinolaryngol Head Neck Surg 2018; 4:67-76. [PMID: 30035264 PMCID: PMC6051256 DOI: 10.1016/j.wjorl.2018.02.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 02/26/2018] [Indexed: 02/08/2023] Open
Abstract
Taste receptors were named for their originally-identified expression on the tongue and role in the sensation of taste (gustation). They are now known to be involved in many chemosensory processes outside the tongue. Expression of the receptors for bitter, sweet, and umami was recently identified in many organs, including the brain, airway, gastrointestinal tract, and reproductive systems. We do not yet know the full roles of these receptors in all of these tissues, nor do we know all of the endogenous ligands that activate them. However, taste receptors are emerging as potentially important therapeutic targets. Moreover, they may mediate some off target effects of drugs, as many medications in common clinical use are known to be bitter. The focus of this review is on recent basic and clinical data describing the expression of bitter (T2R) and sweet (T1R) receptors in the airway and their activation by secreted bacterial compounds. These receptors play important roles in innate immune nitric oxide production and antimicrobial peptide secretion, and may be useful targets for stimulating immune responses in the upper respiratory tract via topical therapies. Moreover, genetic variation in these receptors may play a role in the differential susceptibility of patients to certain types of respiratory infections as well as to differential outcomes in patients with chronic rhinosinusitis (CRS). CRS is a syndrome of chronic upper respiratory infection and inflammation and has a significant detrimental impact on patient quality of life. CRS treatment accounts for approximately 20% of adult antibiotic prescriptions and is thus a large driver of the public health crisis of antibiotic resistance. Taste receptors represent a novel class of therapeutic target to potentially stimulate endogenous immune responses and treat CRS patients without conventional antibiotics.
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Affiliation(s)
- Jenna R Freund
- Department of Otorhinolaryngology-Head and Neck Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Robert J Lee
- Department of Otorhinolaryngology-Head and Neck Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.,Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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70
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Yan CH, Hahn S, McMahon D, Bonislawski D, Kennedy DW, Adappa ND, Palmer JN, Jiang P, Lee RJ, Cohen NA. Nitric oxide production is stimulated by bitter taste receptors ubiquitously expressed in the sinonasal cavity. Am J Rhinol Allergy 2018; 31:85-92. [PMID: 28452704 DOI: 10.2500/ajra.2017.31.4424] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
BACKGROUND Bitter taste receptors (T2R) have recently been demonstrated to contribute to sinonasal innate immunity. One T2R, T2R38, regulates mucosal defense against gram-negative organisms through nitric oxide (NO) production, which enhances mucociliary clearance and directly kills bacteria. To determine whether additional T2Rs contribute to this innate defense, we evaluated two other sinonasal T2Rs (T2R4 and T2R16) for regulation of NO production and expression within the human sinonasal cavity. METHODS Primary human sinonasal cultures were stimulated with ligands specific to T2R4 and T2R16, colchicine and D-salicin, respectively. Cellular NO production was measured by intracellular 4-amino-5-methylamino-2',7'-difluorofluorescein diacetate fluorescence. For T2R expression mapping, sinonasal tissue was obtained from patients who underwent sinus surgery of the middle turbinate, maxillary sinus, ethmoid sinus, or sphenoid sinus. The expression of T2R4, T2R16, and T2R38 was evaluated by using immunofluorescence with validated antibodies. RESULTS Similar to T2R38, T2R4 and T2R16 trigger NO production in a dose-dependent manner by using the canonical taste signaling pathway in response to stimulation with their respective ligands. All three receptors were expressed in the cilia of human epithelial cells of all regions in the sinonasal cavity. CONCLUSION These three T2Rs signaled through the same NO-mediated antimicrobial pathway and were ubiquitously expressed in the sinonasal epithelium. Additional T2Rs besides T2R38 may play a role in sinonasal immune defense. Mapping of T2R expression demonstrated the potential widespread role of T2Rs in sinonasal defense, whereas the genetics of these T2Rs may contribute to our understanding of specific endotypes of chronic rhinosinusitis and develop into novel therapeutic targets.
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Affiliation(s)
- Carol H Yan
- Department of Otorhinolaryngology-Head and Neck Surgery, Division of Rhinology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania, USA
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71
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Triantafillou V, Workman AD, Kohanski MA, Cohen NA. Taste Receptor Polymorphisms and Immune Response: A Review of Receptor Genotypic-Phenotypic Variations and Their Relevance to Chronic Rhinosinusitis. Front Cell Infect Microbiol 2018; 8:64. [PMID: 29564227 PMCID: PMC5845873 DOI: 10.3389/fcimb.2018.00064] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 02/21/2018] [Indexed: 01/22/2023] Open
Abstract
Bitter (T2R) and sweet taste (T1R) receptors have emerged as regulators of upper airway immune responses. Genetic variation of these taste receptors additionally confers susceptibility to infection and has been implicated in severity of disease in chronic rhinosinusitis (CRS). Ongoing taste receptor research has identified a variety of biologically active compounds that activate T1R and T2R receptors, increasing our understanding of not only additional receptor isoforms and their function but also how receptor function may contribute to the pathophysiology of CRS. This review will discuss the function of taste receptors in mediating airway immunity with a focus on recently described modulators of receptor function and directions for future research into the potential role of genotypic and phenotypic receptor variation as a predictor of airway disease and response to therapy.
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Affiliation(s)
- Vasiliki Triantafillou
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA, United States
| | - Alan D Workman
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA, United States
| | - Michael A Kohanski
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA, United States
| | - Noam A Cohen
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA, United States.,Department of Otorhinolaryngology-Head and Neck Surgery, Philadelphia Veterans Affairs Medical Center, Philadelphia, PA, United States
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72
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Kennedy DW. IFAR AUGUST EDITORIAL. Int Forum Allergy Rhinol 2018; 6:781-2. [PMID: 27482703 DOI: 10.1002/alr.21830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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73
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Gurrola J, Borish L. Chronic rhinosinusitis: Endotypes, biomarkers, and treatment response. J Allergy Clin Immunol 2017; 140:1499-1508. [PMID: 29106996 DOI: 10.1016/j.jaci.2017.10.006] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 10/23/2017] [Accepted: 10/24/2017] [Indexed: 12/21/2022]
Abstract
It is increasingly recognized that chronic rhinosinusitis (CRS) comprises a spectrum of different diseases with distinct clinical presentations and pathogenic mechanisms. Defining the distinct phenotypes and endotypes of CRS affects prognosis and, most importantly, is necessary as the basis for making therapeutic decisions. The need for individualized definitions of pathogenic mechanisms before initiating therapy extends to virtually all therapeutic considerations. This is clearly crucial with antibiotics, where, barring an influence from their off-target anti-inflammatory pharmacologic effects, an understanding of the role of the individual biome predicts likelihood of therapeutic benefit. However, this need for identifying individual phenotypes and endotypes also extends to the agent that is currently considered the mainstay of treatment of CRS, specifically glucocorticoids. As with asthma, it is recognized that a large minority of patients with CRS have a steroid-resistant phenotype, identification of which will preclude use of these agents with their potential side effects. Identification of endotypes is also becoming increasingly imperative because targeted biotherapeutic agents, such as anti-IgE and anti-cytokine antibodies, are becoming available. These agents are likely to benefit patients in whom the targeted mediator is not only expressed but demonstrably driving a central mechanism in that patient. In summary, the treatment of CRS is at an exciting crossroad. On the positive side, numerous therapeutics are in development that seem likely to have a positive effect in our patients with this condition. The challenge is that these therapies will require targeted individualized treatments based on identifying subjects with the relevant endotype.
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Affiliation(s)
- Jose Gurrola
- Department of Otolaryngology-Head and Neck Surgery, University of California, San Francisco, Calif.
| | - Larry Borish
- Departments of Medicine and Microbiology, University of Virginia Health Systems, Charlottesville, Va
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Bose S, Grammer LC, Peters AT. Infectious Chronic Rhinosinusitis. THE JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY-IN PRACTICE 2017; 4:584-9. [PMID: 27393772 PMCID: PMC4939240 DOI: 10.1016/j.jaip.2016.04.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 04/05/2016] [Accepted: 04/07/2016] [Indexed: 01/10/2023]
Abstract
Chronic rhinosinusitis (CRS) is a persistent inflammatory disease that affects a multitude of people worldwide. The pathogenesis of CRS involves many factors including genetics, status of the sinonasal microbiome, infections, and environmental influences. Comorbidities associated with CRS include asthma, allergic rhinitis, bronchiectasis, and certain kinds of immunodeficiency. CRS can be divided into different subtypes based on endotypes and phenotypes. Infectious CRS is one such category. The etiology of infectious CRS is usually secondary to chronic bacterial infection that commonly begins with a viral upper respiratory tract infection. Humoral antibody deficiencies can underlie difficult-to-treat or recurrent CRS. Infectious CRS can be treated with antimicrobials, topical or oral corticosteroids, and nasal saline irrigations. Patients with CRS and humoral immunodeficiency may require an aggressive treatment approach including immunoglobulin replacement therapy. Despite advancements in the field of CRS, targeted therapies and reliable biomarkers are still lacking.
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Affiliation(s)
- Sumit Bose
- Division of Allergy-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - Leslie C Grammer
- Division of Allergy-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - Anju T Peters
- Division of Allergy-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Ill.
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Yangyu L, Ranhui X, Xin Z, Jinzhi H, Xin X. [Taste signal transduction and the role of taste receptors in the regulation of microbial infection]. HUA XI KOU QIANG YI XUE ZA ZHI = HUAXI KOUQIANG YIXUE ZAZHI = WEST CHINA JOURNAL OF STOMATOLOGY 2017; 35:549-554. [PMID: 29188655 DOI: 10.7518/hxkq.2017.05.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Taste receptors guide individuals to consume nutrients while avoiding potentially noxious substances. Interestingly, recent studies have shown that taste receptors are also expressed beyond the taste buds, including brain, respiratory system, and digestive system, etc. These extragustatory taste receptors play important roles in microbial infection, nutrient uptake and host homeostasis. Mang extragustatory taste receptors have been proposed to sense microorganisms and regulate host innate defense. More importantly, polymorphisms of genes encoding taste receptor, particularly bitter taste receptor, are linked to different innate defensive responses. This review introduces the molecular basis of taste signal transduction, and the role of taste receptors in the regulation of innate immunity during microbial infection were further discussed in detail.
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Affiliation(s)
- Lu Yangyu
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Dept. of Conservative Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China
| | - Xi Ranhui
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Dept. of Conservative Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China
| | - Zheng Xin
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Dept. of Conservative Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China
| | - He Jinzhi
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Dept. of Conservative Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China
| | - Xu Xin
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Dept. of Conservative Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China
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76
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Verbeurgt C, Veithen A, Carlot S, Tarabichi M, Dumont JE, Hassid S, Chatelain P. The human bitter taste receptor T2R38 is broadly tuned for bacterial compounds. PLoS One 2017; 12:e0181302. [PMID: 28902853 PMCID: PMC5597121 DOI: 10.1371/journal.pone.0181302] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 06/24/2017] [Indexed: 11/18/2022] Open
Abstract
T2R38 has been shown to be a specific bacterial detector implicated in innate immune defense mechanism of human upper airway. Several clinical studies have demonstrated that this receptor is associated with the development of chronic rhinosinusitis (CRS). T2R38 was previously reported to bind to homoserine lactones (HSL), quorum sensing molecules specific of Pseudomonas Aeruginosa and other gram negative species. Nevertheless, these bacteria are not the major pathogens found in CRS. Here we report on the identification of bacterial metabolites acting as new agonists of T2R38 based on a single cell calcium imaging study. Two quorum sensing molecules (Agr D1 thiolactone from Staphylococcus Aureus and CSP-1 from Streptococcus Pneumoniae) and a list of 32 bacterial metabolites from pathogens frequently implicated in CRS were tested. First, we observed that HSL failed to activate T2R38 in our experimental system, but that the dimethylsulfoxide (DMSO), used as a solvent for these lactones may, by itself, account for the agonistic effect previously described. Secondly, we showed that both Agr D1 thiolactone and CSP-1 are inactive but that at least 7 bacterial metabolites (acetone, 2-butanone, 2-pentanone, 2-methylpropanal, dimethyl disulfide, methylmercaptan, γ-butyrolactone) are able to specifically trigger this receptor. T2R38 is thus much more broadly tuned for bacterial compounds than previously thought.
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Affiliation(s)
- Christophe Verbeurgt
- Department of Otorhinolaryngology, Erasme University Hospital, Free University of Brussels, Brussels, Belgium
- * E-mail:
| | | | - Sébastien Carlot
- Department of Otorhinolaryngology, Erasme University Hospital, Free University of Brussels, Brussels, Belgium
| | - Maxime Tarabichi
- Institute of Interdisciplinary Research in human and molecular Biology, Free University of Brussels, Brussels, Belgium
| | - Jacques E. Dumont
- Institute of Interdisciplinary Research in human and molecular Biology, Free University of Brussels, Brussels, Belgium
| | - Sergio Hassid
- Department of Otorhinolaryngology, Erasme University Hospital, Free University of Brussels, Brussels, Belgium
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77
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Fierro F, Suku E, Alfonso-Prieto M, Giorgetti A, Cichon S, Carloni P. Agonist Binding to Chemosensory Receptors: A Systematic Bioinformatics Analysis. Front Mol Biosci 2017; 4:63. [PMID: 28932739 PMCID: PMC5592726 DOI: 10.3389/fmolb.2017.00063] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 08/22/2017] [Indexed: 12/17/2022] Open
Abstract
Human G-protein coupled receptors (hGPCRs) constitute a large and highly pharmaceutically relevant membrane receptor superfamily. About half of the hGPCRs' family members are chemosensory receptors, involved in bitter taste and olfaction, along with a variety of other physiological processes. Hence these receptors constitute promising targets for pharmaceutical intervention. Molecular modeling has been so far the most important tool to get insights on agonist binding and receptor activation. Here we investigate both aspects by bioinformatics-based predictions across all bitter taste and odorant receptors for which site-directed mutagenesis data are available. First, we observe that state-of-the-art homology modeling combined with previously used docking procedures turned out to reproduce only a limited fraction of ligand/receptor interactions inferred by experiments. This is most probably caused by the low sequence identity with available structural templates, which limits the accuracy of the protein model and in particular of the side-chains' orientations. Methods which transcend the limited sampling of the conformational space of docking may improve the predictions. As an example corroborating this, we review here multi-scale simulations from our lab and show that, for the three complexes studied so far, they significantly enhance the predictive power of the computational approach. Second, our bioinformatics analysis provides support to previous claims that several residues, including those at positions 1.50, 2.50, and 7.52, are involved in receptor activation.
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Affiliation(s)
- Fabrizio Fierro
- Computational Biomedicine, Institute for Advanced Simulation IAS-5 and Institute of Neuroscience and Medicine INM-9, Forschungszentrum JülichJülich, Germany
| | - Eda Suku
- Department of Biotechnology, University of VeronaVerona, Italy
| | - Mercedes Alfonso-Prieto
- Computational Biomedicine, Institute for Advanced Simulation IAS-5 and Institute of Neuroscience and Medicine INM-9, Forschungszentrum JülichJülich, Germany.,Cécile and Oskar Vogt Institute for Brain Research, Medical Faculty, Heinrich Heine University DüsseldorfDüsseldorf, Germany
| | - Alejandro Giorgetti
- Computational Biomedicine, Institute for Advanced Simulation IAS-5 and Institute of Neuroscience and Medicine INM-9, Forschungszentrum JülichJülich, Germany.,Department of Biotechnology, University of VeronaVerona, Italy
| | - Sven Cichon
- Institute of Neuroscience and Medicine INM-1, Forschungszentrum JülichJülich, Germany.,Institute for Human Genetics, Department of Genomics, Life&Brain Center, University of BonnBonn, Germany.,Division of Medical Genetics, Department of Biomedicine, University of BaselBasel, Switzerland
| | - Paolo Carloni
- Computational Biomedicine, Institute for Advanced Simulation IAS-5 and Institute of Neuroscience and Medicine INM-9, Forschungszentrum JülichJülich, Germany.,Department of Physics, Rheinisch-Westfälische Technische Hochschule AachenAachen, Germany.,VNU Key Laboratory "Multiscale Simulation of Complex Systems", VNU University of Science, Vietnam National UniversityHanoi, Vietnam
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78
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Carrai M, Campa D, Vodicka P, Flamini R, Martelli I, Slyskova J, Jiraskova K, Rejhova A, Vodenkova S, Canzian F, Bertelli A, Dalla Vedova A, Bavaresco L, Vodickova L, Barale R. Association between taste receptor (TAS) genes and the perception of wine characteristics. Sci Rep 2017; 7:9239. [PMID: 28835712 PMCID: PMC5569080 DOI: 10.1038/s41598-017-08946-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 07/20/2017] [Indexed: 01/26/2023] Open
Abstract
Several studies have suggested a possible relationship between polymorphic variants of the taste receptors genes and the acceptance, liking and intake of food and beverages. In the last decade investigators have attempted to link the individual ability to taste 6-n-propylthiouracil (PROP) and the sensations, such as astringency and bitterness, elicited by wine or its components, but with contradictory results. We have used the genotype instead of the phenotype (responsiveness to PROP or other tastants), to test the possible relation between genetic variability and the perception of wine characteristic in 528 subjects from Italy and the Czech Republic. We observed several interesting associations, among which the association between several TAS2R38 gene single nucleotide polymorphisms (P = 0.002) and the TAS2R16-rs6466849 polymorphism with wine sourness P = 0.0003). These associations were consistent in both populations, even though the country of origin was an important factor in the two models, thus indicating therefore that genetics alongside cultural factors also play a significant role in the individual liking of wine.
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Affiliation(s)
- Maura Carrai
- Department of Biology, Pisa University, Pisa, Italy
| | | | - Pavel Vodicka
- Department of Molecular Biology of Cancer, Institute of Experimental Medicine, Academy of Science of Czech Republic, Prague, Czech Republic.,Institute of Biology and Medical Genetics, 1st Medical Faculty, Charles University, Prague, Czech Republic.,Biomedical Centre, Medical School Pilsen, Charles University in Prague, Pilsen, Czech Republic
| | | | - Irene Martelli
- Sistemi Territoriali S.r.l., 56021, Cascina Loc, San Prospero, Italy
| | - Jana Slyskova
- Department of Molecular Biology of Cancer, Institute of Experimental Medicine, Academy of Science of Czech Republic, Prague, Czech Republic
| | - Katerina Jiraskova
- Department of Molecular Biology of Cancer, Institute of Experimental Medicine, Academy of Science of Czech Republic, Prague, Czech Republic.,Institute of Biology and Medical Genetics, 1st Medical Faculty, Charles University, Prague, Czech Republic
| | - Alexandra Rejhova
- Department of Molecular Biology of Cancer, Institute of Experimental Medicine, Academy of Science of Czech Republic, Prague, Czech Republic
| | - Sona Vodenkova
- Department of Molecular Biology of Cancer, Institute of Experimental Medicine, Academy of Science of Czech Republic, Prague, Czech Republic.,Institute of Biology and Medical Genetics, 1st Medical Faculty, Charles University, Prague, Czech Republic.,1st Medical Faculty, Charles University in Prague, 12000, Prague, Czech Republic
| | - Federico Canzian
- Genomic Epidemiology Group, German Cancer Research Center, Heidelberg, Germany
| | - Alberto Bertelli
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milan, Italy
| | | | - Luigi Bavaresco
- Department of Sustainable Crop Production, Pomology and Viticulture Section, Università Cattolica del Sacro Cuore, Piacenza, Italy
| | - Ludmila Vodickova
- Department of Molecular Biology of Cancer, Institute of Experimental Medicine, Academy of Science of Czech Republic, Prague, Czech Republic.,Institute of Biology and Medical Genetics, 1st Medical Faculty, Charles University, Prague, Czech Republic.,Biomedical Centre, Medical School Pilsen, Charles University in Prague, Pilsen, Czech Republic
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79
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Workman AD, Carey RM, Kohanski MA, Kennedy DW, Palmer JN, Adappa ND, Cohen NA. Relative susceptibility of airway organisms to antimicrobial effects of nitric oxide. Int Forum Allergy Rhinol 2017; 7:770-776. [PMID: 28544570 DOI: 10.1002/alr.21966] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 04/16/2017] [Accepted: 04/27/2017] [Indexed: 01/19/2023]
Abstract
BACKGROUND Nitric oxide (NO) is released in the airway as a critical component of innate immune defense against invading pathogenic organisms. It is well documented that bacteriostatic and bactericidal effects of NO are concentration-dependent. However, few data exist comparing relative susceptibility of common pathogens to NO at physiologic concentrations. In this study we evaluated the effects of NO on 4 common airway bacteria and 1 fungus, and examined the potential implications of discrepancies in sensitivity. METHODS Staphylococcus epidermis, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Candida albicans cultures were adjusted to a uniform optical density (OD) and grown in log phase at 37°C with varying concentrations of NO formed by DETA NONOate. Both OD readings and colony forming units (CFUs) were measured at varying time-points to evaluate for inhibitory effects of NO. RESULTS P aeruginosa and C albicans were significantly more sensitive to NO at physiologic concentrations typical of the human airway. S aureus was attenuated by NO to a lesser degree, and K pneumoniae and S epidermis were more resistant to NO at all concentrations tested. Air surface liquid from cultured human sinonasal epithelial cells had an additive effect in bacterial killing of P aeruginosa, but not in S aureus. CONCLUSION Common airway pathogens have varying levels of susceptibility to NO at physiologic concentrations of innate immune defense. Relative sensitivity of P aeruginosa and relative resistance of S epidermis may help explain the composition of the healthy microbiome, as well as opportunistic infection in the absence of induced NO release.
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Affiliation(s)
- Alan D Workman
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Ryan M Carey
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Michael A Kohanski
- Division of Rhinology, Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA
| | - David W Kennedy
- Division of Rhinology, Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA
| | - James N Palmer
- Division of Rhinology, Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA
| | - Nithin D Adappa
- Division of Rhinology, Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA
| | - Noam A Cohen
- Division of Rhinology, Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA.,Division of Otolaryngology-Head and Neck Surgery, Philadelphia Veterans Administration Medical Center, Philadelphia, PA
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80
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Carey RM, Workman AD, Hatten KM, Siebert AP, Brooks SG, Chen B, Adappa ND, Palmer JN, Kennedy DW, Lee RJ, Cohen NA. Denatonium-induced sinonasal bacterial killing may play a role in chronic rhinosinusitis outcomes. Int Forum Allergy Rhinol 2017; 7:699-704. [PMID: 28544530 DOI: 10.1002/alr.21949] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 04/05/2017] [Accepted: 04/10/2017] [Indexed: 02/02/2023]
Abstract
BACKGROUND Sinonasal bitter taste receptors (T2Rs) contribute to upper airway innate immunity and correlate with chronic rhinosinusitis (CRS) clinical outcomes. A subset of T2Rs expressed on sinonasal solitary chemosensory cells (SCCs) are activated by denatonium, resulting in a calcium-mediated secretion of bactericidal antimicrobial peptides (AMPs) in neighboring ciliated epithelial cells. We hypothesized that there is patient variability in the amount of bacterial killing induced by different concentrations of denatonium and that the differences correlate with CRS clinical outcomes. METHODS Bacterial growth inhibition was quantified after mixing bacteria with airway surface liquid (ASL) collected from denatonium-stimulated sinonasal air-liquid interface (ALI) cultures. Patient ASL bacterial killing at 0.1 mM denatonium and baseline characteristics and sinus surgery outcomes were compared between these populations. RESULTS There is variability in the degree of denatonium-induced bacterial killing between patients. In CRS with nasal polyps (CRSwNP), patients with increased bacterial killing after stimulation with low levels of denatonium undergo significantly more functional endoscopic sinus surgeries (FESSs) (p = 0.037) and have worse 6-month post-FESS 22-item Sino-Nasal Outcome Test (SNOT-22) scores (p = 0.012). CONCLUSION Bacterial killing after stimulation with low levels of denatonium correlates with number of prior FESS and postoperative SNOT-22 scores in CRSwNP. Some symptoms of CRS in patients with hyperresponsiveness to low levels of denatonium may be due to increased airway immune activity or inherent disease severity.
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Affiliation(s)
- Ryan M Carey
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA
| | - Alan D Workman
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA
| | - Kyle M Hatten
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
| | - Adam P Siebert
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
| | - Steven G Brooks
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
| | - Bei Chen
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
| | - Nithin D Adappa
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
| | - James N Palmer
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
| | - David W Kennedy
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
| | - Robert J Lee
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
| | - Noam A Cohen
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA.,Philadelphia Veterans Administration Medical Center Surgical Services, Philadelphia, PA.,Monell Chemical Senses Center, Philadelphia, PA
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81
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Hariri BM, McMahon DB, Chen B, Freund JR, Mansfield CJ, Doghramji LJ, Adappa ND, Palmer JN, Kennedy DW, Reed DR, Jiang P, Lee RJ. Flavones modulate respiratory epithelial innate immunity: Anti-inflammatory effects and activation of the T2R14 receptor. J Biol Chem 2017; 292:8484-8497. [PMID: 28373278 DOI: 10.1074/jbc.m116.771949] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 03/21/2017] [Indexed: 12/18/2022] Open
Abstract
Chronic rhinosinusitis has a significant impact on patient quality of life, creates billions of dollars of annual healthcare costs, and accounts for ∼20% of adult antibiotic prescriptions in the United States. Because of the rise of resistant microorganisms, there is a critical need to better understand how to stimulate and/or enhance innate immune responses as a therapeutic modality to treat respiratory infections. We recently identified bitter taste receptors (taste family type 2 receptors, or T2Rs) as important regulators of sinonasal immune responses and potentially important therapeutic targets. Here, we examined the immunomodulatory potential of flavones, a class of flavonoids previously demonstrated to have antibacterial and anti-inflammatory effects. Some flavones are also T2R agonists. We found that several flavones inhibit Muc5AC and inducible NOS up-regulation as well as cytokine release in primary and cultured airway cells in response to several inflammatory stimuli. This occurs at least partly through inhibition of protein kinase C and receptor tyrosine kinase activity. We also demonstrate that sinonasal ciliated epithelial cells express T2R14, which closely co-localizes (<7 nm) with the T2R38 isoform. Heterologously expressed T2R14 responds to multiple flavones. These flavones also activate T2R14-driven calcium signals in primary cells that activate nitric oxide production to increase ciliary beating and mucociliary clearance. TAS2R38 polymorphisms encode functional (PAV: proline, alanine, and valine at positions 49, 262, and 296, respectively) or non-functional (AVI: alanine, valine, isoleucine at positions 49, 262, and 296, respectively) T2R38. Our data demonstrate that T2R14 in sinonasal cilia is a potential therapeutic target for upper respiratory infections and that flavones may have clinical potential as topical therapeutics, particularly in T2R38 AVI/AVI individuals.
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Affiliation(s)
| | | | - Bei Chen
- Department of Otorhinolaryngology-Head and Neck Surgery
| | | | | | | | | | | | | | - Danielle R Reed
- Monell Chemical Senses Center, Philadelphia, Pennsylvania 19104
| | - Peihua Jiang
- Monell Chemical Senses Center, Philadelphia, Pennsylvania 19104
| | - Robert J Lee
- Department of Otorhinolaryngology-Head and Neck Surgery; Department of Physiology, University of Pennsylvania Perelman School of Medicine, Philadelphia.
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82
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Taste Receptors Mediate Sinonasal Immunity and Respiratory Disease. Int J Mol Sci 2017; 18:ijms18020437. [PMID: 28218655 PMCID: PMC5343971 DOI: 10.3390/ijms18020437] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 02/11/2017] [Accepted: 02/12/2017] [Indexed: 02/07/2023] Open
Abstract
The bitter taste receptor T2R38 has been shown to play a role in the pathogenesis of chronic rhinosinusitis (CRS), where the receptor functions to enhance upper respiratory innate immunity through a triad of beneficial immune responses. Individuals with a functional version of T2R38 are tasters for the bitter compound phenylthiocarbamide (PTC) and exhibit an anti-microbial response in the upper airway to certain invading pathogens, while those individuals with a non-functional version of the receptor are PTC non-tasters and lack this beneficial response. The clinical ramifications are significant, with the non-taster genotype being an independent risk factor for CRS requiring surgery, poor quality-of-life (QOL) improvements post-operatively, and decreased rhinologic QOL in patients with cystic fibrosis. Furthermore, indirect evidence suggests that non-tasters also have a larger burden of biofilm formation. This new data may influence the clinical management of patients with infectious conditions affecting the upper respiratory tract and possibly at other mucosal sites throughout the body.
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83
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Sensory perception of and salivary protein response to astringency as a function of the 6-n-propylthioural (PROP) bitter-taste phenotype. Physiol Behav 2017; 173:163-173. [PMID: 28130087 DOI: 10.1016/j.physbeh.2017.01.031] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 12/21/2016] [Accepted: 01/19/2017] [Indexed: 01/06/2023]
Abstract
Individual differences in astringency perception are poorly understood. Astringency from tannins stimulates the release of specific classes of salivary proteins. These proteins form complexes with tannins, altering their perceived astringency and reducing their bioavailability. We studied the bitter compound, 6-n-propylthioural (PROP), as a phenotypic marker for variation in astringency perception and salivary protein responses. Seventy-nine subjects classified by PROP taster status rated cranberry juice cocktail (CJC; with added sugar) supplemented with 0, 1.5 or 2.0g/L tannic acid (TA). Saliva for protein analyses was collected at rest, or after stimulation with TA or cranberry juice (CJ; without added sugar). CJC with 1.5g/L tannic acid was found to be less astringent, and was liked more by PROP non-taster males than PROP taster males, consistent with the expectation that non-tasters are less sensitive to astringency. Levels of acidic Proline Rich Proteins (aPRPs) and basic Proline Rich Proteins (bPRPs) decreased after TA, while levels of aPRPs, bPRPs and Cystatins unexpectedly rose after CJ. Increases in bPRPs and Cystatins were only observed in PROP tasters. The PROP phenotype plays a gender-specific, but somewhat limited role in the perceived astringency of tannic-acid supplemented, cranberry juice cocktail. The PROP phenotype (regardless of gender) may also be involved in the release of salivary proteins previously implicated in oral health.
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84
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Abstract
Chronic rhinosinusitis (CRS) is a troublesome, chronic inflammatory disease that affects over 10% of the adult population, causing decreased quality of life, lost productivity, and lost time at work and leading to more than a million surgical interventions annually worldwide. The nose, paranasal sinuses, and associated lymphoid tissues play important roles in homeostasis and immunity, and CRS significantly impairs these normal functions. Pathogenic mechanisms of CRS have recently become the focus of intense investigations worldwide, and significant progress has been made. The two main forms of CRS that have been long recognized, with and without nasal polyps, are each now known to be heterogeneous, based on underlying mechanism, geographical location, and race. Loss of the immune barrier, including increased permeability of mucosal epithelium and reduced production of important antimicrobial substances and responses, is a common feature of many forms of CRS. One form of CRS with polyps found worldwide is driven by the cytokines IL-5 and IL-13 coming from Th2 cells, type 2 innate lymphoid cells, and probably mast cells. Type 2 cytokines activate inflammatory cells that are implicated in the pathogenic mechanism, including mast cells, basophils, and eosinophils. New classes of biological drugs that block the production or action of these cytokines are making important inroads toward new treatment paradigms in polypoid CRS.
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Affiliation(s)
- Robert P Schleimer
- Department of Medicine, Division of Allergy-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611;
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85
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Lu P, Zhang CH, Lifshitz LM, ZhuGe R. Extraoral bitter taste receptors in health and disease. J Gen Physiol 2017; 149:181-197. [PMID: 28053191 PMCID: PMC5299619 DOI: 10.1085/jgp.201611637] [Citation(s) in RCA: 132] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 10/06/2016] [Accepted: 12/19/2016] [Indexed: 12/24/2022] Open
Abstract
Bitter taste receptors (TAS2Rs or T2Rs) belong to the superfamily of seven-transmembrane G protein-coupled receptors, which are the targets of >50% of drugs currently on the market. Canonically, T2Rs are located in taste buds of the tongue, where they initiate bitter taste perception. However, accumulating evidence indicates that T2Rs are widely expressed throughout the body and mediate diverse nontasting roles through various specialized mechanisms. It has also become apparent that T2Rs and their polymorphisms are associated with human disorders. In this review, we summarize the physiological and pathophysiological roles that extraoral T2Rs play in processes as diverse as innate immunity and reproduction, and the major challenges in this emerging field.
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Affiliation(s)
- Ping Lu
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA 01605
| | - Cheng-Hai Zhang
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA 01605
| | - Lawrence M Lifshitz
- Biomedical Imaging Group, University of Massachusetts Medical School, Worcester, MA 01605.,Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605
| | - Ronghua ZhuGe
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA 01605 .,Biomedical Imaging Group, University of Massachusetts Medical School, Worcester, MA 01605
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86
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Cohen NA. The genetics of the bitter taste receptor T2R38 in upper airway innate immunity and implications for chronic rhinosinusitis. Laryngoscope 2017; 127:44-51. [PMID: 27650657 PMCID: PMC5177547 DOI: 10.1002/lary.26198] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 06/16/2016] [Indexed: 12/22/2022]
Abstract
OBJECTIVE Chronic rhinosinusitis (CRS) refractory to therapeutic intervention may involve a particularly resistant infection known as a bacterial biofilm. Critical to biofilm formation is the microbial process of quorum sensing whereby microbes secrete factors that regulate the expression of microbial genes involved in biofilm formation, persistence, and virulence. Here, we review recent work demonstrating that the bitter taste receptor T2R38, expressed on the apical surface of the sinonasal epithelium, serves a sentinel role in eavesdropping on microbial quorum-sensing communications and regulates localized innate biocidal defenses. Furthermore, studies investigating whether cilia are necessary for T2R38 expression and function in the upper airway are presented. METHODS Primary human sinonasal air-liquid interface cultures were used to elucidate cellular pathways responsive to quorum-sensing molecules, whereas clinical studies investigated the contribution of T2R38 polymorphisms to recalcitrant chronic rhinosinusitis. RESULTS T2R38 is stimulated by acyl-homoserine lactones, gram-negative quorum-sensing molecules, and subsequently activates nitric oxide-dependent innate immune responses. The formation of mature cilia is necessary for T2R38 expression and function, and polymorphisms that underlie T2R38 functionality appear to be involved in susceptibility to upper respiratory infection and recalcitrant CRS. CONCLUSION Taste receptors are emerging as critical components of early-phase respiratory innate immunity, detecting molecules used by microbes to communicate and stimulating localized host defenses. Genetic polymorphisms are very common within the taste receptors, and recent linkage studies have demonstrated associations of taste receptor genetics with CRS. Lastly, ciliogenesis, which is often impacted in CRS, is critical for the functional expression of T2R38. LEVEL OF EVIDENCE N/A. Laryngoscope, 127:44-51, 2017.
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Affiliation(s)
- Noam A Cohen
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania School of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, U.S.A
- Philadelphia Veterans Affairs Medical Center, Philadelphia, Pennsylvania, U.S.A
- Monell Chemical Senses Center, Philadelphia, Pennsylvania, U.S.A
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87
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Fastenberg JH, Hsueh WD, Mustafa A, Akbar NA, Abuzeid WM. Biofilms in chronic rhinosinusitis: Pathophysiology and therapeutic strategies. World J Otorhinolaryngol Head Neck Surg 2016; 2:219-229. [PMID: 29204570 PMCID: PMC5698538 DOI: 10.1016/j.wjorl.2016.03.002] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2016] [Revised: 03/26/2016] [Accepted: 03/31/2016] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND There is increasing evidence that biofilms are critical to the pathophysiology of chronic infections including chronic rhinosinusitis (CRS). Until relatively recently, our understanding of biofilms was limited. Recent advances in methods for biofilm identification and molecular biology have offered new insights into the role of biofilms in CRS. With these insights, investigators have begun to investigate novel therapeutic strategies that may disrupt or eradicate biofilms in CRS. OBJECTIVE This review seeks to explore the evidence implicating biofilms in CRS, discuss potential anti-biofilm therapeutic strategies, and suggest future directions for research. RESULTS The existing evidence strongly supports the role of biofilms in the pathogenesis of CRS. Several anti-biofilm therapies have been investigated for use in CRS and these are at variable stages of development. Generally, these strategies: 1) neutralize biofilm microbes; 2) disperse existing biofilms; or 3) disrupt quorum sensing. Several of the most promising anti-biofilm therapeutic strategies are reviewed. CONCLUSIONS A better understanding of biofilm function and their contribution to the CRS disease process will be pivotal to the development of novel treatments that may augment and, potentially, redefine the CRS treatment paradigm. There is tremendous potential for future research.
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Affiliation(s)
- Judd H. Fastenberg
- Department of Otorhinolaryngology – Head & Neck Surgery, Montefiore Medical Center, Albert Einstein College of Medicine, 3400 Bainbridge Ave, Bronx, NY, 10467, USA
| | | | | | | | - Waleed M. Abuzeid
- Department of Otorhinolaryngology – Head & Neck Surgery, Montefiore Medical Center, Albert Einstein College of Medicine, 3400 Bainbridge Ave, Bronx, NY, 10467, USA
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88
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Lee RJ, Workman AD, Carey RM, Chen B, Rosen PL, Doghramji L, Adappa ND, Palmer JN, Kennedy DW, Cohen NA. Fungal Aflatoxins Reduce Respiratory Mucosal Ciliary Function. Sci Rep 2016; 6:33221. [PMID: 27623953 PMCID: PMC5021939 DOI: 10.1038/srep33221] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 08/23/2016] [Indexed: 11/29/2022] Open
Abstract
Aflatoxins are mycotoxins secreted by Aspergillus flavus, which can colonize the respiratory tract and cause fungal rhinosinusitis or bronchopulmonary aspergillosis. A. flavus is the second leading cause of invasive aspergillosis worldwide. Because many respiratory pathogens secrete toxins to impair mucociliary immunity, we examined the effects of acute exposure to aflatoxins on airway cell physiology. Using air-liquid interface cultures of primary human sinonasal and bronchial cells, we imaged ciliary beat frequency (CBF), intracellular calcium, and nitric oxide (NO). Exposure to aflatoxins (0.1 to 10 μM; 5 to 10 minutes) reduced baseline (~6-12%) and agonist-stimulated CBF. Conditioned media (CM) from A. fumigatus, A. niger, and A. flavus cultures also reduced CBF by ~10% after 60 min exposure, but effects were blocked by an anti-aflatoxin antibody only with A. flavus CM. CBF reduction required protein kinase C but was not associated with changes in calcium or NO. However, AFB2 reduced NO production by ~50% during stimulation of the ciliary-localized T2R38 receptor. Using a fluorescent reporter construct expressed in A549 cells, we directly observed activation of PKC activity by AFB2. Aflatoxins secreted by respiratory A. flavus may impair motile and chemosensory functions of airway cilia, contributing to pathogenesis of fungal airway diseases.
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Affiliation(s)
- Robert J. Lee
- Department of Otorhinolaryngology – Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
- Department of Physiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
| | - Alan D. Workman
- Department of Otorhinolaryngology – Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
| | - Ryan M. Carey
- Department of Otorhinolaryngology – Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
| | - Bei Chen
- Department of Otorhinolaryngology – Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
| | - Phillip L. Rosen
- Department of Otorhinolaryngology – Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
| | - Laurel Doghramji
- Department of Otorhinolaryngology – Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
| | - Nithin D. Adappa
- Department of Otorhinolaryngology – Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
| | - James N. Palmer
- Department of Otorhinolaryngology – Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
| | - David W. Kennedy
- Department of Otorhinolaryngology – Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
| | - Noam A. Cohen
- Department of Otorhinolaryngology – Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
- Philadelphia VA Medical Center Surgical Services, Philadelphia, Pennsylvania, USA
- Monell Chemical Senses Center, Philadelphia, Pennsylvania, USA
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Abstract
BACKGROUND Protecting the upper airway from microbial infection is an important function of the immune system. Proper detection of these pathogens is paramount for sinonasal epithelial cells to be able to prepare a defensive response. Toll-like receptors and, more recently, bitter taste receptors and sweet taste receptors have been implicated as sensors able to detect the presence of these pathogens and certain compounds that they secrete. Activation of these receptors also triggers innate immune responses to prevent or counteract infection, including mucociliary clearance and the production and secretion of antimicrobial compounds (e.g., defensins). OBJECTIVE To provide an overview of the current knowledge of the role of innate immunity in the upper airway, the mechanisms by which it is carried out, and its clinical relevance. METHODS A literature review of the existing knowledge of the role of innate immunity in the human sinonasal cavity was performed. RESULTS Clinical and basic science studies have shown that the physical epithelial cell barrier, mucociliary clearance, and antimicrobial compound secretion play pivotal innate immune roles in defending the sinonasal cavity from infection. Clinical findings have also linked dysfunction of these defense mechanisms with diseases, such as chronic rhinosinusitis and cystic fibrosis. Recent discoveries have elucidated the significance of bitter and sweet taste receptors in modulating immune responses in the upper airway. CONCLUSION Numerous innate immune mechanisms seem to work in a concerted fashion to keep the sinonasal cavity free of infection. Understanding sinonasal innate immune function and dysfunction in health and disease has important implications for patients with respiratory ailments, such as chronic rhinosinusitis and cystic fibrosis.
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Affiliation(s)
- Benjamin M. Hariri
- From the Department of Otorhinolaryngology—Head and Neck Surgery, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Noam A. Cohen
- From the Department of Otorhinolaryngology—Head and Neck Surgery, University of Pennsylvania, Philadelphia, Pennsylvania
- Surgical Services, Philadelphia VA Medical Center, Philadelphia, Pennsylvania, and
- Monell Chemical Senses Center, Philadelphia, Pennsylvania
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90
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Gallo S, Grossi S, Montrasio G, Binelli G, Cinquetti R, Simmen D, Castelnuovo P, Campomenosi P. TAS2R38 taste receptor gene and chronic rhinosinusitis: new data from an Italian population. BMC MEDICAL GENETICS 2016; 17:54. [PMID: 27515546 PMCID: PMC4982233 DOI: 10.1186/s12881-016-0321-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/28/2015] [Accepted: 06/10/2016] [Indexed: 11/10/2022]
Abstract
BACKGROUND Chronic rhinosinusitis (CRS) is a frequent disease with high social impact and multifactorial pathogenesis. Recently, single nucleotide polymorphisms within the TAS2R38 gene have been implicated as possible contributors to the complex gene-environment interactions in CRS. The purpose of this study was to confirm the proposed correlation between TAS2R38 genotype, CRS and related comorbidities. METHODS Fifty-three CRS patients and 39 healthy individuals were genotyped at the TAS2R38 locus. CRS patients were treated by endoscopic sinus surgery and medical therapies and subdivided in CRS with nasal polyps (CRSwNPs) and CRS without nasal polyps (CRSsNPs). The effect of genotype on CRS and CRS-related comorbidities was assessed. RESULTS The distribution of the different genotypes at the TAS2R38 locus was not significantly different between CRS patients, either with or without nasal polyps, and controls. Besides, no association was found between the different genotypes at the TAS2R38 locus and CRS-related comorbidities. CONCLUSIONS No association was found between TAS2R38 alleles or genotypes and CRS, thus questioning its role in the pathogenesis of CRS.
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Affiliation(s)
- Stefania Gallo
- Clinica Otorinolaringoiatrica, Ospedale di Circolo e Fondazione Macchi, Università degli Studi dell’Insubria, Varese, Italy
- Dipartimento di Biotecnologie e Scienze della Vita (DBSV), Università dell’Insubria, Via J.H. Dunant, 3, Varese, 21100 Italy
| | - Sarah Grossi
- Dipartimento di Biotecnologie e Scienze della Vita (DBSV), Università dell’Insubria, Via J.H. Dunant, 3, Varese, 21100 Italy
| | - Giulia Montrasio
- Clinica Otorinolaringoiatrica, Ospedale di Circolo e Fondazione Macchi, Università degli Studi dell’Insubria, Varese, Italy
| | - Giorgio Binelli
- Dipartimento di Biotecnologie e Scienze della Vita (DBSV), Università dell’Insubria, Via J.H. Dunant, 3, Varese, 21100 Italy
| | - Raffaella Cinquetti
- Dipartimento di Biotecnologie e Scienze della Vita (DBSV), Università dell’Insubria, Via J.H. Dunant, 3, Varese, 21100 Italy
| | - Daniel Simmen
- Center for Rhinology, Skull Base Surgery and Facial Plastic Surgery, ORL-Zentrum, Klinik Hirslanden, Zurich, Switzerland
| | - Paolo Castelnuovo
- Clinica Otorinolaringoiatrica, Ospedale di Circolo e Fondazione Macchi, Università degli Studi dell’Insubria, Varese, Italy
- Dipartimento di Biotecnologie e Scienze della Vita (DBSV), Università dell’Insubria, Via J.H. Dunant, 3, Varese, 21100 Italy
| | - Paola Campomenosi
- Dipartimento di Biotecnologie e Scienze della Vita (DBSV), Università dell’Insubria, Via J.H. Dunant, 3, Varese, 21100 Italy
- The Protein Factory, Centro Interuniversitario di Ricerca in Biotecnologie Proteiche, Politecnico di Milano, ICRM-CNR Milano and Università degli Studi dell’Insubria, Varese, Italy
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91
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Adappa ND, Truesdale CM, Workman AD, Doghramji L, Mansfield C, Kennedy DW, Palmer JN, Cowart BJ, Cohen NA. Correlation of T2R38 taste phenotype and in vitro biofilm formation from nonpolypoid chronic rhinosinusitis patients. Int Forum Allergy Rhinol 2016; 6:783-91. [PMID: 27309535 PMCID: PMC5500301 DOI: 10.1002/alr.21803] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 04/21/2016] [Accepted: 04/29/2016] [Indexed: 02/03/2023]
Abstract
BACKGROUND Sinonasal biofilms have been demonstrated in specimens collected from chronic rhinosinusitis (CRS) patients. Mounting evidence suggests that biofilms contribute to therapeutically recalcitrant CRS. Recently, the bitter taste receptor T2R38 has been implicated in the regulation of the sinonasal mucosal innate immune response. TAS2R38 gene polymorphisms affect receptor functionality and contribute to variations seen in sinonasal innate defense as well as taste perception reflected in gustatory sensitivity to the bitter compound phenylthiocarbamide (PTC). In a population of CRS patients with active infection or inflammation, we sought to determine if a correlation between T2R38 phenotype and in vitro biofilm formation existed. METHODS Endoscopically guided sinonasal swabs were obtained prospectively from CRS (±polyp) patients with evidence of persistent inflammation or mucopurulence. In vitro biofilm formation was assessed with a modified Calgary Biofilm Detection Assay. Patients' phenotypic (functional) expression of the bitter taste receptor T2R38 was evaluated with a taste test including the compound PTC. Linear regression was used to determine the level of significance between mean in vitro biofilm formation levels and mean PTC taste test intensity ratings across CRS patients. RESULTS Sinonasal swabs were obtained from 59 patients, with 42 of the 59 samples demonstrating in vitro biofilm formation. Analysis revealed an inverse linear association between in vitro biofilm formation and PTC taste intensity ratings (p = 0.019) for all patients. This association was exclusively driven by nonpolypoid CRS patients (p = 0.0026). CONCLUSION In vitro biofilm formation from sinonasal clinical isolates is inversely correlated with PTC taste sensitivity in nonpolypoid CRS patients.
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Affiliation(s)
- Nithin D. Adappa
- Department of Otorhinolaryngology–Head and Neck Surgery, Hospital of the University of Pennsylvania, Philadelphia, PA
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA
| | - Carl M. Truesdale
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA
| | - Alan D. Workman
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA
| | - Laurel Doghramji
- Department of Otorhinolaryngology–Head and Neck Surgery, Hospital of the University of Pennsylvania, Philadelphia, PA
| | | | - David W. Kennedy
- Department of Otorhinolaryngology–Head and Neck Surgery, Hospital of the University of Pennsylvania, Philadelphia, PA
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA
| | - James N. Palmer
- Department of Otorhinolaryngology–Head and Neck Surgery, Hospital of the University of Pennsylvania, Philadelphia, PA
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA
| | | | - Noam A. Cohen
- Department of Otorhinolaryngology–Head and Neck Surgery, Hospital of the University of Pennsylvania, Philadelphia, PA
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA
- Monell Chemical Senses Center, Philadelphia, PA
- Surgical Service, Philadelphia Veterans Administration Medical Center, Philadelphia, PA
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92
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Hariri BM, Payne SJ, Chen B, Mansfield C, Doghramji LJ, Adappa ND, Palmer JN, Kennedy DW, Niv MY, Lee RJ. In vitro effects of anthocyanidins on sinonasal epithelial nitric oxide production and bacterial physiology. Am J Rhinol Allergy 2016; 30:261-8. [PMID: 27456596 PMCID: PMC4953345 DOI: 10.2500/ajra.2016.30.4331] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND T2R bitter taste receptors play a crucial role in sinonasal innate immunity by upregulating mucociliary clearance and nitric oxide (NO) production in response to bitter gram-negative quorum-sensing molecules in the airway surface liquid. Previous studies showed that phytochemical flavonoid metabolites, known as anthocyanidins, taste bitter and have antibacterial effects. Our objectives were to examine the effects of anthocyanidins on NO production by human sinonasal epithelial cells and ciliary beat frequency, and their impact on common sinonasal pathogens Pseudomonas aeruginosa and Staphylococcus aureus. METHODS Ciliary beat frequency and NO production were measured by using digital imaging of differentiated air-liquid interface cultures prepared from primary human cells isolated from residual surgical material. Plate-based assays were used to determine the effects of anthocyanidins on bacterial swimming and swarming motility. Biofilm formation and planktonic growth were also assessed. RESULTS Anthocyanidin compounds triggered epithelial cells to produce NO but not through T2R receptors. However, anthocyanidins did not impact ciliary beat frequency. Furthermore, they did not reduce biofilm formation or planktonic growth of P. aeruginosa. In S. aureus, they did not reduce planktonic growth, and only one compound had minimal antibiofilm effects. The anthocyanidin delphinidin and anthocyanin keracyanin were found to promote bacterial swimming, whereas anthocyanidin cyanidin and flavonoid myricetin did not. No compounds that were tested inhibited bacterial swarming. CONCLUSION Results of this study indicated that, although anthocyanidins may elicited an innate immune NO response from human cells, they do not cause an increase in ciliary beating and they may also cause a pathogenicity-enhancing effect in P. aeruginosa. Additional studies are necessary to understand how this would affect the use of anthocyanidins as therapeutics. This study emphasized the usefulness of in vitro screening of candidate compounds against multiple parameters of both epithelial and bacterial physiologies to prioritize candidates for in vivo therapeutic testing.
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Affiliation(s)
- Benjamin M. Hariri
- From the Department of Otorhinolaryngology—Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Sakeena J. Payne
- Division of Otolaryngology, Department of Surgery, Pennsylvania State University Milton S. Hershey Medical Center, Hershey, Pennsylvania
| | - Bei Chen
- From the Department of Otorhinolaryngology—Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | | | - Laurel J. Doghramji
- From the Department of Otorhinolaryngology—Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Nithin D. Adappa
- From the Department of Otorhinolaryngology—Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - James N. Palmer
- From the Department of Otorhinolaryngology—Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - David W. Kennedy
- From the Department of Otorhinolaryngology—Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Masha Y. Niv
- The Institute of Biochemistry, Food and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Israel, and
| | - Robert J. Lee
- From the Department of Otorhinolaryngology—Head and Neck Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
- Department of Physiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
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93
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Carey RM, Adappa ND, Palmer JN, Lee RJ, Cohen NA. Taste Receptors: Regulators of Sinonasal Innate Immunity. Laryngoscope Investig Otolaryngol 2016; 1:88-95. [PMID: 27819057 PMCID: PMC5089074 DOI: 10.1002/lio2.26] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Taste receptors in the oral cavity guide our preferences for foods, preventing toxic ingestions and encouraging proper nutrient consumption. More recently, expression of taste receptors has been demonstrated in other locations throughout the body, including the airway, gastrointestinal tract, pancreas, and brain. The extent and specific roles of extraoral taste receptors are largely unknown, but a growing body of evidence suggests that taste receptors in the airway serve a critical role in sensing bacteria and regulating innate immunity. This review will focus on the function of bitter and sweet taste receptors in the human airway, with particular emphasis on T2R38, a bitter taste receptor found in sinonasal ciliated cells, and the bitter and sweet receptors found on specialized sinonasal solitary chemosensory cells. The importance of these novel taste receptor‐immune circuits in the human airway and their clinical relevance in airway disease will also be reviewed.
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Affiliation(s)
- Ryan M Carey
- Department of Otorhinolaryngology, Perelman School of Medicine, University of Pennsylvania, Ravdin Building, 5 floor, Philadelphia, PA 19104
| | - Nithin D Adappa
- Department of Otorhinolaryngology, Perelman School of Medicine, University of Pennsylvania, Ravdin Building, 5 floor, Philadelphia, PA 19104
| | - James N Palmer
- Department of Otorhinolaryngology, Perelman School of Medicine, University of Pennsylvania, Ravdin Building, 5 floor, Philadelphia, PA 19104
| | - Robert J Lee
- Department of Otorhinolaryngology, Perelman School of Medicine, University of Pennsylvania, Ravdin Building, 5 floor, Philadelphia, PA 19104
| | - Noam A Cohen
- Department of Otorhinolaryngology, Perelman School of Medicine, University of Pennsylvania, Ravdin Building, 5 floor, Philadelphia, PA 19104
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94
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Stevens WW, Lee RJ, Schleimer RP, Cohen NA. Chronic rhinosinusitis pathogenesis. J Allergy Clin Immunol 2016; 136:1442-1453. [PMID: 26654193 DOI: 10.1016/j.jaci.2015.10.009] [Citation(s) in RCA: 221] [Impact Index Per Article: 27.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 10/21/2015] [Accepted: 10/21/2015] [Indexed: 02/07/2023]
Abstract
There are a variety of medical conditions associated with chronic sinonasal inflammation, including chronic rhinosinusitis (CRS) and cystic fibrosis. In particular, CRS can be divided into 2 major subgroups based on whether nasal polyps are present or absent. Unfortunately, clinical treatment strategies for patients with chronic sinonasal inflammation are limited, in part because the underlying mechanisms contributing to disease pathology are heterogeneous and not entirely known. It is hypothesized that alterations in mucociliary clearance, abnormalities in the sinonasal epithelial cell barrier, and tissue remodeling all contribute to the chronic inflammatory and tissue-deforming processes characteristic of CRS. Additionally, the host innate and adaptive immune responses are also significantly activated and might be involved in pathogenesis. Recent advancements in the understanding of CRS pathogenesis are highlighted in this review, with special focus placed on the roles of epithelial cells and the host immune response in patients with cystic fibrosis, CRS without nasal polyps, or CRS with nasal polyps.
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Affiliation(s)
- Whitney W Stevens
- Division of Allergy-Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - Robert J Lee
- Department of Otorhinolaryngology-Head and Neck Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pa; Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pa
| | - Robert P Schleimer
- Division of Allergy-Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill; Department of Otolaryngology, Northwestern University Feinberg School of Medicine, Chicago, Ill.
| | - Noam A Cohen
- Department of Otorhinolaryngology-Head and Neck Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pa; Philadelphia Veterans Affairs Medical Center, Surgical Service, Philadelphia, Pa; Monell Chemical Senses Center, Philadelphia, Pa
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95
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Avau B, Depoortere I. The bitter truth about bitter taste receptors: beyond sensing bitter in the oral cavity. Acta Physiol (Oxf) 2016; 216:407-20. [PMID: 26493384 DOI: 10.1111/apha.12621] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 09/28/2015] [Accepted: 10/14/2015] [Indexed: 11/26/2022]
Abstract
The bitter taste receptor (TAS2R)-family of G-protein-coupled receptors has been identified on the tongue as detectors of bitter taste over a decade ago. In the last few years, they have been discovered in an ever growing number of extra-oral tissues, including the airways, the gut, the brain and even the testis. In tissues that contact the exterior, protective functions for TAS2Rs have been proposed, in analogy to their function on the tongue as toxicity detector. However, TAS2Rs have also been found in internal organs, suggesting other roles for these receptors, perhaps involving as yet unidentified endogenous ligands. The current review gives an overview of the different proposed functions for TAS2Rs in tissues other than the oral cavity; from appetite regulation to the treatment of asthma, regulation of gastrointestinal motility and control of airway innate immunity.
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Affiliation(s)
- B. Avau
- Translational Research Center for Gastrointestinal Disorders (TARGID); Gut Peptide Research Lab; University of Leuven; Leuven Belgium
| | - I. Depoortere
- Translational Research Center for Gastrointestinal Disorders (TARGID); Gut Peptide Research Lab; University of Leuven; Leuven Belgium
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96
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Shaik FA, Singh N, Arakawa M, Duan K, Bhullar RP, Chelikani P. Bitter taste receptors: Extraoral roles in pathophysiology. Int J Biochem Cell Biol 2016; 77:197-204. [PMID: 27032752 DOI: 10.1016/j.biocel.2016.03.011] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2016] [Revised: 03/16/2016] [Accepted: 03/22/2016] [Indexed: 11/17/2022]
Abstract
Over the past decade tremendous progress has been made in understanding the functional role of bitter taste receptors (T2Rs) and bitter taste perception. This review will cover the recent advances made in identifying the role of T2Rs in pathophysiological states. T2Rs are widely expressed in various parts of human anatomy and have been shown to be involved in physiology of respiratory system, gastrointestinal tract and endocrine system. Empirical evidence has shown T2Rs to be an integral component of antimicrobial immune responses in upper respiratory tract infections. The studies on human airway smooth muscle cells have shown that a potent bitter tastant induced bronchodilatory effects mediated by bitter taste receptors. Clinical data suggests a role for T2R38 polymorphism in predisposition of individuals to chronic rhinosinusitis. The role of genetic variation in T2Rs and its impact on disease susceptibility have been investigated in various other disease risk factors such as alcohol dependence, head and neck cancers. Preliminary reports have demonstrated differential expression of functional T2Rs in breast cancer cell lines. Studies on the role of T2Rs in pathophysiology of diseases including chronic rhinosinusitis, asthma, cystic fibrosis, and cancer have been promising. However, research in this field is in its nascent stages, and more confirmatory studies on animal models and in clinical settings are required.
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Affiliation(s)
- Feroz Ahmed Shaik
- Manitoba Chemosensory Biology (MCSB) Research Group and Department of Oral Biology, University of Manitoba, Winnipeg, MB R3E 0W2, Canada; Children's Hospital Research Institute of Manitoba, Winnipeg, MB R3E 3P4, Canada
| | - Nisha Singh
- Manitoba Chemosensory Biology (MCSB) Research Group and Department of Oral Biology, University of Manitoba, Winnipeg, MB R3E 0W2, Canada; Children's Hospital Research Institute of Manitoba, Winnipeg, MB R3E 3P4, Canada
| | - Makoto Arakawa
- Manitoba Chemosensory Biology (MCSB) Research Group and Department of Oral Biology, University of Manitoba, Winnipeg, MB R3E 0W2, Canada
| | - Kangmin Duan
- Manitoba Chemosensory Biology (MCSB) Research Group and Department of Oral Biology, University of Manitoba, Winnipeg, MB R3E 0W2, Canada; Children's Hospital Research Institute of Manitoba, Winnipeg, MB R3E 3P4, Canada
| | - Rajinder P Bhullar
- Manitoba Chemosensory Biology (MCSB) Research Group and Department of Oral Biology, University of Manitoba, Winnipeg, MB R3E 0W2, Canada
| | - Prashen Chelikani
- Manitoba Chemosensory Biology (MCSB) Research Group and Department of Oral Biology, University of Manitoba, Winnipeg, MB R3E 0W2, Canada; Children's Hospital Research Institute of Manitoba, Winnipeg, MB R3E 3P4, Canada; Department of Pharmacology and Therapeutics, University of Manitoba, Winnipeg, MB R3E 0W2, Canada.
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97
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Workman AD, Palmer JN, Adappa ND, Cohen NA. The Role of Bitter and Sweet Taste Receptors in Upper Airway Immunity. Curr Allergy Asthma Rep 2016; 15:72. [PMID: 26492878 DOI: 10.1007/s11882-015-0571-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Over the past several years, taste receptors have emerged as key players in the regulation of innate immune defenses in the mammalian respiratory tract. Several cell types in the airway, including ciliated epithelial cells, solitary chemosensory cells, and bronchial smooth muscle cells, all display chemoresponsive properties that utilize taste receptors. A variety of bitter products secreted by microbes are detected with resultant downstream inflammation, increased mucous clearance, antimicrobial peptide secretion, and direct bacterial killing. Genetic variation of bitter taste receptors also appears to play a role in the susceptibility to infection in respiratory disease states, including that of chronic rhinosinusitis. Ongoing taste receptor research may yield new therapeutics that harness innate immune defenses in the respiratory tract and may offer alternatives to antibiotic treatment. The present review discusses taste receptor-protective responses and analyzes the role these receptors play in mediating airway immune function.
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Affiliation(s)
- Alan D Workman
- Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania Medical Center, 5th Floor Ravdin Building, 3400 Spruce Street, Philadelphia, PA, 19104, USA.,Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - James N Palmer
- Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania Medical Center, 5th Floor Ravdin Building, 3400 Spruce Street, Philadelphia, PA, 19104, USA.,Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Nithin D Adappa
- Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania Medical Center, 5th Floor Ravdin Building, 3400 Spruce Street, Philadelphia, PA, 19104, USA.,Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Noam A Cohen
- Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania Medical Center, 5th Floor Ravdin Building, 3400 Spruce Street, Philadelphia, PA, 19104, USA. .,Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA. .,Monell Smell and Taste Center, Philadelphia, PA, USA. .,Philadelphia Veterans Affairs Medical Center, Philadelphia, PA, USA.
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98
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Orlandi RR, Kingdom TT, Hwang PH, Smith TL, Alt JA, Baroody FM, Batra PS, Bernal-Sprekelsen M, Bhattacharyya N, Chandra RK, Chiu A, Citardi MJ, Cohen NA, DelGaudio J, Desrosiers M, Dhong HJ, Douglas R, Ferguson B, Fokkens WJ, Georgalas C, Goldberg A, Gosepath J, Hamilos DL, Han JK, Harvey R, Hellings P, Hopkins C, Jankowski R, Javer AR, Kern R, Kountakis S, Kowalski ML, Lane A, Lanza DC, Lebowitz R, Lee HM, Lin SY, Lund V, Luong A, Mann W, Marple BF, McMains KC, Metson R, Naclerio R, Nayak JV, Otori N, Palmer JN, Parikh SR, Passali D, Peters A, Piccirillo J, Poetker DM, Psaltis AJ, Ramadan HH, Ramakrishnan VR, Riechelmann H, Roh HJ, Rudmik L, Sacks R, Schlosser RJ, Senior BA, Sindwani R, Stankiewicz JA, Stewart M, Tan BK, Toskala E, Voegels R, Wang DY, Weitzel EK, Wise S, Woodworth BA, Wormald PJ, Wright ED, Zhou B, Kennedy DW. International Consensus Statement on Allergy and Rhinology: Rhinosinusitis. Int Forum Allergy Rhinol 2016; 6 Suppl 1:S22-209. [DOI: 10.1002/alr.21695] [Citation(s) in RCA: 333] [Impact Index Per Article: 41.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 11/13/2015] [Accepted: 11/16/2015] [Indexed: 02/06/2023]
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Valerie Lund
- Royal National Throat Nose and Ear Hospital; London UK
| | - Amber Luong
- University of Texas Medical School at Houston
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99
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Douglas JE, Saunders CJ, Reed DR, Cohen NA. A role for airway taste receptor modulation in the treatment of upper respiratory infections. Expert Rev Respir Med 2016; 10:157-70. [PMID: 26731661 DOI: 10.1586/17476348.2016.1135742] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Taste receptors, initially identified in the oral epithelium, have since been shown to be widely distributed, being found in the upper and lower respiratory tracts, gastrointestinal epithelium, thyroid, and brain. The presence of taste receptors in the nasal epithelium has led to the discovery of their role in innate immunity, defending the paranasal sinuses against pathogens. This article addresses the current paradigm for understanding the role of extraoral taste receptors, specifically the T2R38 bitter taste receptor and the T1R2+3 sweet taste receptor, in respiratory innate defenses and presents evidence for the use of these and other taste receptors as therapeutic targets in the management of chronic rhinosinusitis. Future studies should focus on understanding the polymorphisms of taste receptors beyond T2R38 to fully elucidate their potential therapeutic use and lay the groundwork for their modulation in a clinical setting to decrease the health impact and economic burden of upper respiratory disease.
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Affiliation(s)
- Jennifer E Douglas
- a Perelman School of Medicine , University of Pennsylvania , Philadelphia , PA , USA.,b Department of Otorhinolaryngology-Head and Neck Surgery , University of Pennsylvania Health System , Philadelphia , PA , USA.,c Monell Chemical Senses Center , Philadelphia , PA , USA
| | - Cecil J Saunders
- b Department of Otorhinolaryngology-Head and Neck Surgery , University of Pennsylvania Health System , Philadelphia , PA , USA
| | | | - Noam A Cohen
- a Perelman School of Medicine , University of Pennsylvania , Philadelphia , PA , USA.,b Department of Otorhinolaryngology-Head and Neck Surgery , University of Pennsylvania Health System , Philadelphia , PA , USA.,c Monell Chemical Senses Center , Philadelphia , PA , USA.,d Philadelphia Veterans Affairs Medical Center Surgical Services , Philadelphia , PA , USA
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Abstract
Chronic rhinosinusitis (CRS) is a common inflammatory disease that results in a significant decrease in patient quality of life and a large economic burden. However, the lack of population-based epidemiologic studies and robust model systems has made it difficult to fully elucidate the key inflammatory pathways that drive the chronic inflammatory responses observed in CRS. This review will highlight the wide variety of factors that likely contribute to CRS disease pathogenesis. Defects in the innate immune function of the airway epithelium, including decreases in barrier function, mucociliary clearance, and production of antimicrobial peptides, all likely play a role in the initial inflammatory response. Subsequent recruitment and activation of eosinophils, mast cells, and innate lymphoid cells (ILCs) further contributes to the chronic inflammatory response and directly activates adaptive immune cells, including T and B cells. However, development of new tools and model systems is still needed to further understand the chronicity of this inflammatory response and which specific factors are necessary or sufficient to drive CRS pathogenesis. Such studies will be critical for the development of improved therapeutic strategies aimed at treating this highly prevalent and costly disease.
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Affiliation(s)
- Kathryn E Hulse
- Division of Allergy-Immunology, Department of Medicine, Feinberg School of Medicine, Northwestern University, 240 E. Huron St., McGaw Rm M-302, Chicago, IL, 60611, USA.
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