Lee, Hojoon; Macpherson, Lindsey J; Parada, Camilo A; Zuker, Charles S; Ryba, Nicholas J P
In mammals, taste buds typically contain 50-100 tightly packed taste-receptor cells (TRCs), representing all five basic qualities: sweet, sour, bitter, salty and umami. Notably, mature taste cells have life spans of only 5-20 days and, consequently, are constantly replenished by differentiation of taste stem cells. Given the importance of establishing and maintaining appropriate connectivity between TRCs and their partner ganglion neurons (that is, ensuring that a labelled line from sweet TRCs connects to sweet neurons, bitter TRCs to bitter neurons, sour to sour, and so on), we examined how new connections are specified to retain fidelity of signal transmission. Here we show that bitter and sweet TRCs provide instructive signals to bitter and sweet target neurons via different guidance molecules (SEMA3A and SEMA7A). We demonstrate that targeted expression of SEMA3A or SEMA7A in different classes of TRCs produces peripheral taste systems with miswired sweet or bitter cells. Indeed, we engineered mice with bitter neurons that now responded to sweet tastants, sweet neurons that responded to bitter or sweet neurons responding to sour stimuli. Together, these results uncover the basic logic of the wiring of the taste system at the periphery, and illustrate how a labelled-line sensory circuit preserves signalling integrity despite rapid and stochastic turnover of receptor cells.
Thomas R. Scott
Full Text Available Taste is the final arbiter of which chemicals from the environment will be admitted to the body. The action of swallowing a substance leads to a physiological consequence of which the taste system should be informed. Accordingly, taste neurons in the central nervous system are closely allied with those that receive input from the viscera so as to monitor the impact of a recently ingested substance. There is behavioral, anatomical, electrophysiological, gene expression, and neurochemical evidence that the consequences of ingestion influence subsequent food selection through development of either a conditioned taste aversion (if illness ensues or a conditioned taste preference (if satiety. This ongoing communication between taste and the viscera permits the animal to tailor its taste system to its individual needs over a lifetime.
Roossien, A; Brunsting, [No Value; Zaagsma, J; Zijlstra, WG; Muntinga, JHJ
The reactions of the vagal cardioaccelerator (VCA) system to changes in mean arterial pressure (MAP) were studied in five beta -adrenoceptor blocked conscious dogs. An increase in MAP was obtained by administration of vasopressin or methoxamine, a decrease by doxazosin or nitroprusside. In the first
Full Text Available Although paroxysmal atrial fibrillation (AF is known to be initiated by rapid firing of pulmonary veins (PV and non-PV triggers, the crucial role of cardiac autonomic nervous system (ANS in the initiation and maintenance of AF has long been appreciated in both experimental and clinical studies. The cardiac intrinsic ANS is composed of ganglionated plexi (GPs, located close to the left atrium-pulmonary vein junctions and a vast network of interconnecting neurons. Ablation strategies aiming for complete PV isolation (PVI remain the cornerstone of AF ablation procedures. However, several observational studies and few randomized studies have suggested that GP ablation, as an adjunctive strategy, might achieve better clinical outcomes in patients undergoing radiofrequency-based PVI for both paroxysmal and nonparoxysmal AF. In these patients, vagal reactions (VR such as vagally mediated bradycardia or asystole are thought to reflect intrinsic cardiac ANS modulation and/or denervation. Vagal reactions occurring during cryoballoon- (CB- based PVI have been previously reported; however, little is known on resulting ANS modulation and/or prevalence and significance of vagal reactions during PVI with the CB technique. We conducted a review of prevalence, putative mechanisms, and significance of VR during CB-based PVI.
Ikenaga, Takanori; Ogura, Tatsuya; Finger, Thomas E
The sense of taste is crucial in an animal's determination as to what is edible and what is not. This gustatory function is especially important in goldfish, who utilize a sophisticated oropharyngeal sorting mechanism to separate food from substrate material. The computational aspects of this detection are carried out by the medullary vagal lobe, which is a large, laminated structure combining elements of both the gustatory nucleus of the solitary tract and the nucleus ambiguus. The sensory layers of the vagal lobe are coupled to the motor layers via a simple reflex arc. Details of this reflex circuit were investigated with histology and calcium imaging. Biocytin injections into the motor layer labeled vagal reflex interneurons that have radially directed dendrites ramifying within the layers of primary afferent terminals. Axons of reflex interneurons extend radially inward to terminate onto both vagal motoneurons and small, GABAergic interneurons in the motor layer. Functional imaging shows increases in intracellular Ca++ of vagal motoneurons following electrical stimulation in the sensory layer. These responses were suppressed under Ca(++)-free conditions and by interruption of the axons bridging between the sensory and motor layers. Pharmacological experiments showed that glutamate acting via (+/-)-alpha-amino-3-hydroxy- 5-ethylisoxazole-4-propioinc acid (AMPA)/kainate and N-methyl-D-aspartic acid (NMDA) receptors mediate neurotransmission between reflex interneurons and vagal motoneurons. Thus, the vagal gustatory portion of the viscerosensory complex is linked to branchiomotor neurons of the pharynx via a glutamatergic interneuronal system.
Full Text Available The insect gustatory receptors (GRs are members of a large G-protein coupled receptor family distantly related to the insect olfactory receptors. They are phylogenetically different from taste receptors of most other animals. GRs are often coexpressed with other GRs in single receptor neurons. Taste receptors other than GRs are also expressed in some neurons. Recent molecular studies in the fruitfly Drosophila revealed that the insect taste receptor system not only covers a wide ligand spectrum of sugars, bitter substances or salts that are common to mammals but also includes reception of pheromone and somatosensory stimulants. However, the central mechanism to perceive and discriminate taste information is not yet elucidated. Analysis of the primary projection of taste neurons to the brain shows that the projection profiles depend basically on the peripheral locations of the neurons as well as the GRs that they express. These results suggest that both peripheral and central design principles of insect taste perception are different from those of olfactory perception.
IJpma, Irene; Timmermans, Erik R.; Renken, Remco J.; Horst, ter Gert; Reyners, Anna K. L.
A metallic taste is reported by cancer patients as a side effect of systemic therapy. Despite the high prevalence, this taste alteration has received limited attention. The present study investigated: 1) the prevalence of metallic taste in cancer patients treated with systemic therapy; 2) possible
Lee, Ji-Hee; Choi, Goeun; Oh, Yeon-Ji; Park, Je Won; Choy, Young Bin; Park, Mung Chul; Yoon, Yeo Joon; Lee, Hwa Jeong; Chang, Hee Chul; Choy, Jin-Ho
A nanohybrid was prepared with an inorganic clay material, montmorillonite (MMT), for taste masking of sildenafil (SDN). To further improve the taste-masking efficiency and enhance the drug-release rate, we coated the nanohybrid of SDN–MMT with a basic polymer, polyvinylacetal diethylaminoacetate (AEA). Powder X-ray diffraction and Fourier transform infrared experiments showed that SDN was successfully intercalated into the interlayer space of MMT. The AEA-coated SDN–MMT nanohybrid showed drug release was much suppressed at neutral pH (release rate, 4.70 ± 0.53%), suggesting a potential for drug taste masking at the buccal cavity. We also performed in vitro drug release experiments in a simulated gastric fluid (pH = 1.2) and compared the drug-release profiles of AEA-coated SDN–MMT and Viagra®, an approved dosage form of SDN. As a result, about 90% of SDN was released from the AEA-coated SDN–MMT during the first 2 hours while almost 100% of drug was released from Viagra®. However, an in vivo experiment showed that the AEA-coated SDN–MMT exhibited higher drug exposure than Viagra®. For the AEA-coated SDN–MMT, the area under the plasma concentration– time curve from 0 hours to infinity (AUC0-∞) and maximum concentration (Cmax) were 78.8 ± 2.32 μg · hour/mL and 12.4 ± 0.673 μg/mL, respectively, both of which were larger than those obtained with Viagra® (AUC0-∞ = 69.2 ± 3.19 μg · hour/mL; Cmax = 10.5 ± 0.641 μg/mL). Therefore, we concluded that the MMT-based nanohybrid is a promising delivery system for taste masking of SDN with possibly improved drug exposure. PMID:22619517
Meng, Lingbin; Jiang, Xin; Ji, Rui
Taste system is a perfect system to study degeneration and regeneration after nerve injury because the taste system is highly plastic and the regeneration is robust. Besides, degeneration and regeneration can be easily measured since taste buds arise in discrete locations, and nerves that innervate them can be accurately quantified. Neurotrophins are a family of proteins that regulate neural survival, function, and plasticity after nerve injury. Recent studies have shown that neurotrophins play an important role in the developmental and mature taste system, indicating neurtrophin might also regulate taste system following gustatory nerve injury. This review will summarize how taste system degenerates and regenerates after gustatory nerve cut and conclude potential roles of neurotrophin in regulating the process.
Lee, Ji-Hee; Choi, Goeun; Oh, Yeon-Ji; Park, Je Won; Choy, Young Bin; Park, Mung Chul; Yoon, Yeo Joon; Lee, Hwa Jeong; Chang, Hee Chul; Choy, Jin-Ho
A nanohybrid was prepared with an inorganic clay material, montmorillonite (MMT), for taste masking of sildenafil (SDN). To further improve the taste-masking efficiency and enhance the drug-release rate, we coated the nanohybrid of SDN-MMT with a basic polymer, polyvinylacetal diethylaminoacetate (AEA). Powder X-ray diffraction and Fourier transform infrared experiments showed that SDN was successfully intercalated into the interlayer space of MMT. The AEA-coated SDN-MMT nanohybrid showed drug release was much suppressed at neutral pH (release rate, 4.70 ± 0.53%), suggesting a potential for drug taste masking at the buccal cavity. We also performed in vitro drug release experiments in a simulated gastric fluid (pH = 1.2) and compared the drug-release profiles of AEA-coated SDN-MMT and Viagra(®), an approved dosage form of SDN. As a result, about 90% of SDN was released from the AEA-coated SDN-MMT during the first 2 hours while almost 100% of drug was released from Viagra(®). However, an in vivo experiment showed that the AEA-coated SDN-MMT exhibited higher drug exposure than Viagra(®). For the AEA-coated SDN-MMT, the area under the plasma concentration- time curve from 0 hours to infinity (AUC(0-∞)) and maximum concentration (C(max)) were 78.8 ± 2.32 μg · hour/mL and 12.4 ± 0.673 μg/mL, respectively, both of which were larger than those obtained with Viagra(®) (AUC(0-∞) = 69.2 ± 3.19 μg · hour/mL; C(max) = 10.5 ± 0.641 μg/mL). Therefore, we concluded that the MMT-based nanohybrid is a promising delivery system for taste masking of SDN with possibly improved drug exposure.
Lee, Minju; Jung, Je Won; Kim, Daesan; Ahn, Young-Joon; Hong, Seunghun; Kwon, Hyung Wook
We report a floating electrode-based bioelectronic tongue mimicking insect taste systems for the detection and discrimination of umami substances. Here, carbon nanotube field-effect transistors with floating electrodes were hybridized with nanovesicles containing honeybee umami taste receptor, gustatory receptor 10 of Apis mellifera (AmGr10). This strategy enables us to discriminate between l-monosodium glutamate (MSG), best-known umami tastant, and non-umami substances with a high sensitivity and selectivity. It could also be utilized for the detection of MSG in liquid food such as chicken stock. Moreover, we demonstrated the synergism between MSG and disodium 5'-inosinate (IMP) for the umami taste using this platform. This floating electrode-based bioelectronic tongue mimicking insect taste systems can be a powerful platform for various applications such as food screening, and it also can provide valuable insights on insect taste systems.
Kentish, Stephen J; Page, Amanda J
Vagal afferents are a vital link between the peripheral tissue and central nervous system (CNS). There is an abundance of vagal afferents present within the proximal gastrointestinal tract which are responsible for monitoring and controlling gastrointestinal function. Whilst essential for maintaining homeostasis there is a vast amount of literature emerging which describes remarkable plasticity of vagal afferents in response to endogenous as well as exogenous stimuli. This plasticity for the most part is vital in maintaining healthy processes; however, there are increased reports of vagal plasticity being disrupted in pathological states, such as obesity. Many of the disruptions, observed in obesity, have the potential to reduce vagal afferent satiety signalling which could ultimately perpetuate the obese state. Understanding how plasticity occurs within vagal afferents will open a whole new understanding of gut function as well as identify new treatment options for obesity. Copyright © 2014 Elsevier Inc. All rights reserved.
Dunipace, L; Meister, S; McNealy, C; Amrein, H
Taste is an important sensory modality in most animals. In Drosophila, taste is perceived by gustatory neurons located in sensilla distributed on several different appendages throughout the body of the animal. Here we show that the gustatory receptors are encoded by a family of at least 54 genes (Gr genes), most of which are expressed exclusively in a small subset of taste sensilla located in narrowly defined regions of the fly's body. BLAST searches with the predicted amino acid sequences of 6 7-transmembrane-receptor genes of unknown function and 20 previously identified, putative gustatory receptor genes led to the identification of a large gene family comprising at least 54 genes. We investigated the expression of eight genes by using a Gal4 reporter gene assay and found that five of them were expressed in the gustatory system of the fly. Four genes were expressed in 1%-4% of taste sensilla, located in well-defined regions of the proboscis, the legs, or both. The fifth gene was expressed in about 20% of taste sensilla in all major gustatory organs, including the taste bristles on the anterior wing margin. Axon-tracing experiments demonstrated that neurons expressing a given Gr gene project their axons to a spatially restricted domain of the subesophageal ganglion in the fly brain. Our findings suggest that each taste sensillum represents a discrete, functional unit expressing at least one Gr receptor and that most Gr genes are expressed in spatially restricted domains of the gustatory system. These observations imply the potential for high taste discrimination of the Drosophila brain.
Wistoft, Karen; Qvortrup, Lars
The article presents a proposal for a didactics of taste and a reflection theory of taste didactics. Inspired and informed by systems theory, this proposal includes two aspects of taste education. The first section deals with taste as the content of teaching. Here, the intention is to enable...... students to learn about taste. This section presents a systematic division of taste into its four main dimensions: The dimension of good taste, the dimension of healthy taste, the dimension of perceived taste, and the dimension of moral taste. The second section comprises taste as an instrument of teaching....... Here, the intention is to use ‘taste’ as a means to teach home economics and food education. This section answers the question of how to teach in a way that enables the students to develop knowledge and skills in relation to the four dimensions of taste. In this section four knowledge types...
Bachmanov, Alexander A.; Bosak, Natalia P.; Lin, Cailu; Matsumoto, Ichiro; Ohmoto, Makoto; Reed, Danielle R.; Nelson, Theodore M.
Taste receptors function as one of the interfaces between internal and external milieus. Taste receptors for sweet and umami (T1R [taste receptor, type 1]), bitter (T2R [taste receptor, type 2]), and salty (ENaC [epithelial sodium channel]) have been discovered in the recent years, but transduction mechanisms of sour taste and ENaC-independent salt taste are still poorly understood. In addition to these five main taste qualities, the taste system detects such noncanonical “tastes” as water, fat, and complex carbohydrates, but their reception mechanisms require further research. Variations in taste receptor genes between and within vertebrate species contribute to individual and species differences in taste-related behaviors. These variations are shaped by evolutionary forces and reflect species adaptations to their chemical environments and feeding ecology. Principles of drug discovery can be applied to taste receptors as targets in order to develop novel taste compounds to satisfy demand in better artificial sweeteners, enhancers of sugar and sodium taste, and blockers of bitterness of food ingredients and oral medications. PMID:23886383
Full Text Available Vagal sensory neurons mediate the vago-vagal reflex which, in turn, regulates a wide array of gastrointestinal functions including esophageal motility, gastric accommodation and pancreatic enzyme secretion. These neurons also transmit sensory information from the gut to the central nervous system, which then mediates the sensations of nausea, fullness and satiety. Recent research indicates that vagal afferent neurons process non-uniform properties and a significant degree of plasticity. These properties are important to ensure that vagally regulated gastrointestinal functions respond rapidly and appropriately to various intrinsic and extrinsic factors. Similar plastic changes in the vagus also occur in pathophysiological conditions, such as obesity and diabetes, resulting in abnormal gastrointestinal functions. A clear understanding of the mechanisms which mediate these events may provide novel therapeutic targets for the treatment of gastrointestinal disorders due to vago-vagal pathway malfunctions.
Kim, Yong-Sung; Kim, Yong-Suk
There are several methods available in measuring food taste. The sensory evaluation, for instance, is a typical method for panels to test of taste and recognize smell with their nose by measuring the degree of taste characteristic, intensity, and pleasure. There are many issues entailed in the traditional sensory evaluation method such as forming a panel and evaluation cost; moreover, it is only localized in particular areas. Accordingly, this paper aimed to select food in one particular area, and compare and review the content between sensory evaluations using a taste biological sensor, as well as presenting an analysis of brainwaves using EEG and finally a proposal of a new method for sensory evaluation. In this paper, the researchers have conducted a sensory evaluation whereas a maximum of nine points were accumulated by purchasing eight types of rice wine. These eight types of Makgeolli were generalized by generating multidimensional data with the use of TS-5000z, thus learning mapping points and scaling them. The contribution of this paper, therefore, is to overcome the disadvantages of the sensory evaluation with the usage of the suggested taste biological sensor system.
Full Text Available Feeding behavior is regulated by a complex interplay of many endogenous substances, such as peptides and neurotransmitters in the central nervous system. Histamine is a neurotransmitter which expresses an anorectic effect on food intake via histamine H1 receptors. The histaminergic system exists downstream of leptin, a satiety factor secreted from white adipose tissue. Because direct stimulation of the histaminergic system by histamine H3-inverse agonists or antagonists can normalize the obese phenotype in which animal models with exogenous leptin resistance, which resembles human obesity, the potential roles of histamine H3 receptors as a therapeutic target now draw attention. Histaminergic activity is enhanced during feeding, and an oral somatic sensation is thought to affect histaminergic activity while blood glucose levels do not. In addition, gustatory information can modulate histaminergic activity by two mechanisms: by physiological excitation of the chorda tympani nerve, one of the taste nerves, and by emotions elicited by taste perception, i.e. taste palatability. Particularly, aversive and hazardous taste stimuli tonically facilitate histaminergic activity, suggesting that the histaminergic system is involved in the response to harmful stimuli. Together with recent findings, it is postulated that the histaminergic system responds to both mechanical and chemical sensory input from the oral cavity during feeding and is exerted as a part of the danger response system.
Taché, Yvette; Adelson, David; Yang, Hong
Pavlov's seminal findings in the early twentieth century showed that the sight, smell or taste of food in dogs with chronic esophagostomy induces a vagal-dependent gastric acid secretion. These observations established the concept of the cephalic phase of digestion. Compelling experimental evidence in rats indicates that the three amino acid peptide thyrotropin-releasing hormone (TRH) expressed in the brainstem plays a key role in the vagal stimulation of gastric function. Neurons in the dorsal motor nucleus of the vagus (DMN) expressed TRH receptor subtype (TRH-R1) and received efferent input from TRH containing fibers arising from TRH synthesizing neurons in the raphe pallidus, raphe obscurus, and the parapyramidal regions. TRH microinjected into the DMN or intracisternally excites the firing of DMN neurons and stimulates efferent activity in the gastric branch of the vagus nerve and gastric myenteric cholinergic neurons. At the functional level, this results in a vagally-mediated and atropine-sensitive stimulation of gastric epithelial and endocrine cells secreting acid, pepsin, serotonin, histamine and ghrelin, and enteric neurons leading to increased gastric motility and emptying. Importantly, the blockade of TRH or TRH-R1 in the brainstem by pretreatment into the cisterna magna or the DMN with TRH antibody or TRH-R1 oligodeoxynucleotide antisense respectively abolishes the stimulation of gastric acid induced by sham-feeding. The gastric response to TRH injected into the DMN is potentiated by serotonin and the proTRH flanking peptide, Ps4 and suppressed by a number of brainstem peptides and cytokines activated during stress or immune response and inhibiting food intake and gastric acid secretion. These convergent data strongly support a physiological involvement of TRH signaling pathway in the brainstem to stimulate vagal activity and identified TRH-TRH-R1 system as a major effector in the dorsal vagal complex to drive the vagally mediated gut response
Reutter, K. (Tuebingen Univ. (Germany, F.R.))
The trace metal Zn seems to be essential for the normal functioning of the gustatory sense. It was tried to localize Zn within the peripheral and central parts of the bullhead's gustatory system by the use of scanning electron microscopy and X-ray microanalysis. In freeze dried preparations of the bullhead's barbel taste buds (and the taste buds of rabbits) Zn is found in randomly distributed granules, which cannot be related to distinct taste bud regions. Furthermore, Zn occurs in subunits of the central gustatory nuclei, the vagal and facial lobe of the rhombencephalon. Therefore Zn appears to be essential for intact peripheral as well as central gustatory processes, at least in lower vertebrates.
Hubert, D.; Keppens, A.; Lambert, J.-C.; Granville, J.; Hendrick, F.; Verhoelst, T.
Over the past two decades the Multi-TASTE validation system has proven its value in the characterisation and support to the development of atmospheric composition measurements by ESA's GOME, Envisat and Third Party Missions (TPMs). We give an overview of the capabilities and the latest results of this comprehensive, versatile and semi-operational system and address its relevance regarding the recommendations voiced at ATMOS 2012.
Full Text Available Most animals possess taste receptors neurons detecting potentially noxious compounds. In humans, the ligands which activate these neurons define a sensory space called bitter. By extension, this term has been used in animals and insects to define molecules which induce aversive responses. In this review, based on our observations carried out in Drosophila, we examine how bitter compounds are detected and if the activation of bitter-sensitive neurons respond only to molecules bitter to humans. Like most animals, flies detect bitter chemicals through a specific population of taste neurons, distinct from those responding to sugars or to other modalities. Activating bitter-sensitive taste neurons induce aversive reactions and inhibits feeding. Bitter molecules also contribute to the suppression of sugar-neuron responses and can lead to a complete inhibition of the responses to sugar at the periphery. Since some bitter molecules activate bitter-sensitive neurons and some inhibit sugar detection, bitter molecules are represented by two sensory spaces which are only partially congruent. In addition to molecules which impact feeding, we recently discovered that the activation of bitter-sensitive neurons also induces grooming. Bitter-sensitive neurons of the wings and of the legs can sense chemicals from the gram negative bacteria, Escherichia coli, thus adding another biological function to these receptors. Bitter-sensitive neurons of the proboscis also respond to inhibitory pheromones such as 7-tricosene. Activating these neurons by bitter molecules in the context of sexual encounter inhibits courting and sexual reproduction, while activating these neurons with 7-tricosene in a feeding context will inhibit feeding. The picture that emerges from these observations is that the taste system is composed of detectors which monitor different categories of ligands, which facilitate or inhibit behaviors depending on the context (feeding, sexual reproduction
This paper explores taste in the context of phenomenology and outlines possibilities for situating a phenomenological approach to taste within the framework of educational theory. In such an approach, taste emerges as a complex interaction between all senses and as interplay between recollection...... and anticipation. In this respect, taste-experience is indicative of a privileged but hitherto relatively unexplored access to cognition. It is a sensory encounter that encompasses possibilities for learning, not only about taste but also about other subjects through taste. Key-words: sensory experience, taste...
Crouzet, Sébastien M; Busch, Niko A; Ohla, Kathrin
In most species, the sense of taste is key in the distinction of potentially nutritious and harmful food constituents and thereby in the acceptance (or rejection) of food. Taste quality is encoded by specialized receptors on the tongue, which detect chemicals corresponding to each of the basic tastes (sweet, salty, sour, bitter, and savory ), before taste quality information is transmitted via segregated neuronal fibers , distributed coding across neuronal fibers , or dynamic firing patterns  to the gustatory cortex in the insula. In rodents, both hardwired coding by labeled lines  and flexible, learning-dependent representations  and broadly tuned neurons  seem to coexist. It is currently unknown how, when, and where taste quality representations are established in the cortex and whether these representations are used for perceptual decisions. Here, we show that neuronal response patterns allow to decode which of four tastants (salty, sweet, sour, and bitter) participants tasted in a given trial by using time-resolved multivariate pattern analyses of large-scale electrophysiological brain responses. The onset of this prediction coincided with the earliest taste-evoked responses originating from the insula and opercular cortices, indicating that quality is among the first attributes of a taste represented in the central gustatory system. These response patterns correlated with perceptual decisions of taste quality: tastes that participants discriminated less accurately also evoked less discriminated brain response patterns. The results therefore provide the first evidence for a link between taste-related decision-making and the predictive value of these brain response patterns. Copyright © 2015 Elsevier Ltd. All rights reserved.
Kaltsum, U.; Triyana, K.; Siswanta, D.
In Indonesia, herbal medicines are usually produced by small and medium enterprises which are relatively low in quality control. The purpose of this paper is to report that we have developed a taste sensor system with global selectivity, i.e., electronic tongue (e-tongue) for differentiation of Indonesian herbal medicines. The e-tongue was composed of five kinds of ion selective electrodes as working electrodes, data acquisition system, and pattern recognition system. Each ion selective electrode (ISE) was built by attaching lipid/polymer membrane. For this purpose, the five kinds of membranes were built by mixing lipid, plasticizer (nitrophenyl octyl ether/NPOE), polyvinyl chloride (PVC), and tetrahydrofuran (THF). In this study, we employed five kinds of lipid, namely oleic acid (OA), dioctyl phosphate (DOP), decyl alcohol (DA), dodecylamine (DDC), and trioctyl methyl ammonium chloride (TOMA). In this case, the membranes transform information of taste substances into electric signal. The five kinds of Indonesian herbal medicine were purchased from local supermarket in Yogyakarta, i.e., kunyit asam (made from turmeric and tamarind), beras kencur (made from rice and kencur), jahe wangi (made from ginger and fragrance), sirih wangi (made from betel leaf), and temulawak (made from Javanese ginger). Prior to detecting the taste from the Indonesian herbal medicine samples, each ion selective electrode was tested with five basic taste samples, i.e., for saltiness, sweetness, umami, bitterness, and sourness. All ISEs showed global selectivity to all samples. Furthermore, the array of ISEs showed specific response pattern to each Indonesian herbal medicine. For pattern recognition system, we employed principle component analysis (PCA). As a result, the e-tongue was able to differentiate five kinds of Indonesian herbal medicines, proven by the total variance of first and second principle components is about 93%. For the future, the e-tongue may be developed for quality
Kaltsum, U., E-mail: email@example.com [Physics Education Department, IKIP PGRI Semarang (Indonesia); Triyana, K., E-mail: firstname.lastname@example.org; Siswanta, D., E-mail: email@example.com [Physics Department, Gadjah Mada University (Indonesia)
In Indonesia, herbal medicines are usually produced by small and medium enterprises which are relatively low in quality control. The purpose of this paper is to report that we have developed a taste sensor system with global selectivity, i.e., electronic tongue (e-tongue) for differentiation of Indonesian herbal medicines. The e-tongue was composed of five kinds of ion selective electrodes as working electrodes, data acquisition system, and pattern recognition system. Each ion selective electrode (ISE) was built by attaching lipid/polymer membrane. For this purpose, the five kinds of membranes were built by mixing lipid, plasticizer (nitrophenyl octyl ether/NPOE), polyvinyl chloride (PVC), and tetrahydrofuran (THF). In this study, we employed five kinds of lipid, namely oleic acid (OA), dioctyl phosphate (DOP), decyl alcohol (DA), dodecylamine (DDC), and trioctyl methyl ammonium chloride (TOMA). In this case, the membranes transform information of taste substances into electric signal. The five kinds of Indonesian herbal medicine were purchased from local supermarket in Yogyakarta, i.e., kunyit asam (made from turmeric and tamarind), beras kencur (made from rice and kencur), jahe wangi (made from ginger and fragrance), sirih wangi (made from betel leaf), and temulawak (made from Javanese ginger). Prior to detecting the taste from the Indonesian herbal medicine samples, each ion selective electrode was tested with five basic taste samples, i.e., for saltiness, sweetness, umami, bitterness, and sourness. All ISEs showed global selectivity to all samples. Furthermore, the array of ISEs showed specific response pattern to each Indonesian herbal medicine. For pattern recognition system, we employed principle component analysis (PCA). As a result, the e-tongue was able to differentiate five kinds of Indonesian herbal medicines, proven by the total variance of first and second principle components is about 93%. For the future, the e-tongue may be developed for quality
Shandilya, Jayasha; Gao, Yankun; Nayak, Tapan K; Roberts, Stefan G E; Medler, Kathryn F
The sense of taste is used by organisms to achieve the optimal nutritional requirement and avoid potentially toxic compounds. In the oral cavity, taste receptor cells are grouped together in taste buds that are present in specialized taste papillae in the tongue. Taste receptor cells are the cells that detect chemicals in potential food items and transmit that information to gustatory nerves that convey the taste information to the brain. As taste cells are in contact with the external environment, they can be damaged and are routinely replaced throughout an organism's lifetime to maintain functionality. However, this taste cell turnover loses efficiency over time resulting in a reduction in taste ability. Currently, very little is known about the mechanisms that regulate the renewal and maintenance of taste cells. We therefore performed RNA-sequencing analysis on isolated taste cells from 2 and 6-month-old mice to determine how alterations in the taste cell-transcriptome regulate taste cell maintenance and function in adults. We found that the activator protein-1 (AP1) transcription factors (c-Fos, Fosb and c-Jun) and genes associated with this pathway were significantly downregulated in taste cells by 6 months and further declined at 12 months. We generated conditional c-Fos-knockout mice to target K14-expressing cells, including differentiating taste cells. c-Fos deletion caused a severe perturbation in taste bud structure and resulted in a significant reduction in the taste bud size. c-Fos deletion also affected taste cell turnover as evident by a decrease in proliferative marker, and upregulation of the apoptotic marker cleaved-PARP. Thus, AP1 factors are important regulators of adult taste cell renewal and their downregulation negatively impacts taste maintenance.
Goto, Tazuko K; Yeung, Andy Wai Kan; Suen, Justin Long Kiu; Fong, Barry Siu Keung; Ninomiya, Yuzo
Time-intensity sensory evaluation of human taste perception is useful to know the feedback of a taste stimulus from tongue. However, it has not been profiled together with reaction time under the constant stimulating tongue in high time resolution. We first made intra-oral device to deliver taste solution to anterior, lateral and posterior tongue in standardized condition. Second, we developed a time-intensity sensory evaluation meter linked to synchronized taste solution delivery system. Time-intensity profiles were recorded in higher temporal resolution than our past study. Third, we analyzed the corrected taste quality reaction time from raw sensory perception data, and following sensory evaluation profile. The new method acquired taste sensory evaluation data with 1 ms temporal resolution and found the reaction timing was 908 ms, the corrected taste quality reaction time was 712 ms, maximum intensity was 3.47, and corrected time to reach maximum intensity was 1312 ms. The coefficient of variation ranged from 0.007 to 0.236 indicating low variance. Time-intensity sensory evaluation in this study did not sacrifice the feature of raw data. The relative comparison of time-intensity sensory profile among subjects will be available in this system in future study, while it was still difficult to define the absolute value of reaction time. Our method could gather real-time feedback for the time-intensity sensory evaluation of a taste stimulus under the standardized stimulating tongue. This could be useful for establishing database of time-intensity sensory profiles for comparison of delicate taste perceptions. Copyright © 2015 Elsevier B.V. All rights reserved.
The interest of this paper is to position taste within the framework of time. This might seem peculiar given that taste, in its physical sense, is referred to as an ephemeral experience taking place in the mouth. Taste, however, is more than that. It is the transient experience that infiltrates...... the body in the act of eating and, at the same time, it has associative powers that allow taste to transcend the instantaneous sensory encounter. Taste is a synthesis of multiple sensory impressions involving all five senses, each sense contributing with a particular facet of sensory experience....... But this does not mean that taste is entirely individual. It goes beyond the sphere of the individual in the sense that taste can be handed over and thus lay out a basis for shared remembrance. The focal point will be the interplay between the individual taste-experiences of various registers of tastes...
Rudnitskaya, Alisa [CESAM and Chemistry Department, University of Aveiro, Aveiro (Portugal); Kirsanov, Dmitry, E-mail: firstname.lastname@example.org [Chemistry Department, St. Petersburg University, St. Petersburg (Russian Federation); Blinova, Yulia [Chemistry Department, St. Petersburg University, St. Petersburg (Russian Federation); Legin, Evgeny [Sensor Systems LLC, St. Petersburg (Russian Federation); Seleznev, Boris [Chemistry Department, St. Petersburg University, St. Petersburg (Russian Federation); Clapham, David; Ives, Robert S.; Saunders, Kenneth A. [GlaxoSmithKline Pharmaceuticals, Gunnels Wood Road, Stevenage (United Kingdom); Legin, Andrey [Chemistry Department, St. Petersburg University, St. Petersburg (Russian Federation)
Highlights: ► Chemically diverse APIs are studied with potentiometric “electronic tongue”. ► Bitter taste of APIs can be predicted with 3wayPLS regression from ET data. ► High correlation of ET assessment with human panel and rat in vivo model. -- Abstract: The application of the potentiometric multisensor system (electronic tongue, ET) for quantification of the bitter taste of structurally diverse active pharmaceutical ingredients (API) is reported. The measurements were performed using a set of bitter substances that had been assessed by a professional human sensory panel and the in vivo rat brief access taste aversion (BATA) model to produce bitterness intensity scores for each substance at different concentrations. The set consisted of eight substances, both inorganic and organic – azelastine, caffeine, chlorhexidine, potassium nitrate, naratriptan, paracetamol, quinine, and sumatriptan. With the aim of enhancing the response of the sensors to the studied APIs, measurements were carried out at different pH levels ranging from 2 to 10, thus promoting ionization of the compounds. This experiment yielded a 3 way data array (samples × sensors × pH levels) from which 3wayPLS regression models were constructed with both human panel and rat model reference data. These models revealed that artificial assessment of bitter taste with ET in the chosen set of API's is possible with average relative errors of 16% in terms of human panel bitterness score and 25% in terms of inhibition values from in vivo rat model data. Furthermore, these 3wayPLS models were applied for prediction of the bitterness in blind test samples of a further set of API's. The results of the prediction were compared with the inhibition values obtained from the in vivo rat model.
Page, A J; Kentish, S J
The vagal link between the gastrointestinal tract and the central nervous system (CNS) has numerous vital functions for maintaining homeostasis. The regulation of energy balance is one which is attracting more and more attention due to the potential for exploiting peripheral hormonal targets as treatments for conditions such as obesity. While physiologically, this system is well tuned and demonstrated to be effective in the regulation of both local function and promoting/terminating food intake the neural connection represents a susceptible pathway for disruption in various disease states. Numerous studies have revealed that obesity in particularly is associated with an array of modifications in vagal afferent function from changes in expression of signaling molecules to altered activation mechanics. In general, these changes in vagal afferent function in obesity further promote food intake instead of the more desirable reduction in food intake. It is essential to gain a comprehensive understanding of the mechanisms responsible for these detrimental effects before we can establish more effective pharmacotherapies or lifestyle strategies for the treatment of obesity and the maintenance of weight loss. © 2016 John Wiley & Sons Ltd.
Schmidt, Liane; Skvortsova, Vasilisa; Kullen, Claus; Weber, Bernd; Plassmann, Hilke
Informational cues such as the price of a wine can trigger expectations about its taste quality and thereby modulate the sensory experience on a reported and neural level. Yet it is unclear how the brain translates such expectations into sensory pleasantness. We used a whole-brain multilevel mediation approach with healthy participants who tasted identical wines cued with different prices while their brains were scanned using fMRI. We found that the brain's valuation system (BVS) in concert with the anterior prefrontal cortex played a key role in implementing the effect of price cues on taste pleasantness ratings. The sensitivity of the BVS to monetary rewards outside the taste domain moderated the strength of these effects. These findings provide novel evidence for the fundamental role that neural pathways linked to motivation and affective regulation play for the effect of informational cues on sensory experiences.
Barreiro-Iglesias, Antón; Anadón, Ramón; Rodicio, María Celina
The present is a review of the gustatory system of lampreys, which are representative of the earliest vertebrates. They are the oldest extant vertebrates that possess taste buds. Because of the phylogenetic position of lampreys, the study of their gustatory system will provide important information to help understand the early evolution of this system in vertebrates. The taste buds of larval lampreys, which are papillae located on the first six pairs of gill arches facing the water current, respond to classical taste substances. They consist of two types of tall differentiated cells, serotonergic biciliated taste receptors ('light' cells) and microvillous sustentacular cells ('dark cells'). The taste buds also contain basal proliferative cells. Afferent gustatory fibers of the glossopharyngeal and vagal nerves innervate the taste buds of lampreys and contact the basal surface of the biciliated cells without entering the bud. Central processes of the glossopharyngeal and vagal cranial nerves terminate in a caudal rhombencephalic region that may correspond to the nucleus of the solitary tract of gnathostomes. To date, most studies in lampreys have focused on characterizing taste buds; future research should focus on the central processing of the gustatory information. Here we will review the current knowledge about the gustatory system of lampreys to provide a basis for establishing the direction of further studies of this chemosensory system. Copyright 2010 S. Karger AG, Basel.
Liman, Emily R.; Zhang, Yali V.; Montell, Craig
Five canonical tastes, bitter, sweet, umami (amino acid), salty and sour (acid) are detected by animals as diverse as fruit flies and humans, consistent with a near universal drive to consume fundamental nutrients and to avoid toxins or other harmful compounds. Surprisingly, despite this strong conservation of basic taste qualities between vertebrates and invertebrates, the receptors and signaling mechanisms that mediate taste in each are highly divergent. The identification over the last two decades of receptors and other molecules that mediate taste has led to stunning advances in our understanding of the basic mechanisms of transduction and coding of information by the gustatory systems of vertebrates and invertebrates. In this review, we discuss recent advances in taste research, mainly from the fly and mammalian systems, and we highlight principles that are common across species, despite stark differences in receptor types. PMID:24607224
Noorian, Ali Reza; Rha, Jennifer; Annerino, Dana M; Bernhard, Douglas; Taylor, Georgia M; Greene, James G
Gastrointestinal (GI) dysfunction is the one of the most common non-motor symptoms of Parkinson's disease (PD) and occurs in nearly every patient afflicted with this common neurodegenerative disorder. While parkinsonian motor symptoms are caused by degeneration of dopamine neurons in the midbrain substantia nigra, the neurological localization of non-motor symptoms in PD is not known. In this study, we examined a transgenic mouse model of PD in which mutant (A53T) human α-synuclein was expressed under control of the prion promoter (AS mice). We found that gastrointestinal expression of human α-synuclein in this transgenic line was limited to efferent fibers projecting from the dorsal motor nucleus of the vagus nerve (DMV) to the enteric nervous system (ENS). Older transgenic mice had a lower density of human α-synuclein expression in the GI tract, suggesting an age-related disruption of efferent vagal fibers in this model. At the same time, mice developed age-related declines in stool frequency and gastric emptying consistent with those seen in human PD. These behavioral and neuropathological patterns parallel those seen in PD patients and suggest the DMV as a target for further investigation into causes for GI neuropathology and symptomatology in parkinsonism. Copyright © 2012 Elsevier Inc. All rights reserved.
Chatterjee, Abhishek; Hardin, Paul E
Circadian clocks keep time in the digestive, circulatory, reproductive, excretory and nervous systems even in absence of external cues. Central oscillators in the brain control locomotor activity of organisms ranging from fruit flies to man, but the functions of the clocks in peripheral nervous system are not well understood. The presence of autonomous peripheral oscillators in the major taste organ of Drosophila, the proboscis, prompted us to test whether gustatory responses are under control of the circadian clock. We find that synchronous rhythms in physiological and behavioral responses to attractive and aversive tastants are driven by oscillators in gustatory receptor neurons (GRNs); primary sensory neurons that carry taste information from the proboscis to the brain. During the middle of the night, high levels of G protein-coupled receptor kinase 2 (GPRK2) in the GRNs suppresses tastant-evoked responses. Flies with disrupted gustatory clocks are hyperphagic and hyperactive, recapitulating behaviors typically seen under the stress of starvation. Temporal plasticity in innate behaviors should offer adaptive advantages to flies. In this Extra View article we discuss how oscillators inside GRNs regulate responsiveness to tastants and influence feeding, metabolism and general activity.
Sabbatini, Maurizio; Grossini, Elena; Molinari, Claudio; Mary, David A S G; Vacca, Giovanni; Cannas, Mario
Various hindbrain nuclei have been demonstrated to be involved in the control of the cardiovascular reflexes elicited by both non-noxious and noxious gastric distension, through parasympathetic and sympathetic activation. The different role played by the branches of autonomic nervous system in exerting these effects and their crosstalk in relation to low-/high-pressure distension rate has not been examined yet. Therefore, in the present work, monolateral and bilateral vagotomy and splanchnicotomy were performed in anesthetised rats to analyse the involvement of hindbrain nuclei in haemodynamic changes caused by gastric distension at high (80 mmHg) and low (15 mmHg) pressure. The analysis of c-Fos expression in neuronal areas involved in cardiovascular control allowed us to examine their recruitment in response to various patterns of gastric distension and the crosstalk between vagal and splanchnic systems. The results obtained show that the low-pressure (non-noxious) gastric distension increases both heart rate and arterial blood pressure. In addition, the vagus nerve and hindbrain nuclei, such as nucleus ambiguous, ventrolateral medulla and lateral reticular nucleus, appear to be primarily involved in observed responses. In particular, we have found that although vagus nerve plays a central role in exerting those cardiovascular reflex changes at low gastric distension, for its functional expression an intact splanchnic system is mandatory. Hence, the absence of splanchnic input attenuates pressor responses or turns them into depressor responses. Instead at high-pressure (noxious) gastric distension, the splanchnic nerve represents the primary component in regulating the reflex cardiovascular effects.
Johannessen, Helene; Revesz, David; Kodama, Yosuke
BACKGROUND: Recently, the US FDA has approved "vagal blocking therapy or vBLoc® therapy" as a new treatment for obesity. The aim of the present study was to study the mechanism-of-action of "VBLOC" in rat models. METHODS: Rats were implanted with VBLOC, an intra-abdominal electrical device...
Shigemura, Noriatsu; Ninomiya, Yuzo
The sense of taste conveys crucial information about the quality and nutritional value of foods before it is ingested. Taste signaling begins with taste cells via taste receptors in oral cavity. Activation of these receptors drives the transduction systems in taste receptor cells. Then particular transmitters are released from the taste cells and activate corresponding afferent gustatory nerve fibers. Recent studies have revealed that taste sensitivities are defined by distinct taste receptors and modulated by endogenous humoral factors in a specific group of taste cells. Such peripheral taste generations and modifications would directly influence intake of nutritive substances. This review will highlight current understanding of molecular mechanisms for taste reception, signal transduction in taste bud cells, transmission between taste cells and nerves, regeneration from taste stem cells, and modification by humoral factors at peripheral taste organs. Copyright © 2016 Elsevier Inc. All rights reserved.
Ordelman, Simone Cornelia Maria Anna; Kornet, L.; Cornelussen, R.; Buschman, H.P.J.; Veltink, Petrus H.
The cardiovascular system can be influenced by electrically stimulating the vagal nerve. Selectivity for specific cardiac fibers may be limited when stimulating at the cervical level. Our objective was to increase effectiveness and selectivity for cardiovascular effects of vagal nerve stimulation by
Full Text Available Scientists from Oregon State University, USA, came up with the newest theory of the sixth taste – starch taste that might soon join the basic five tastes. This argument is supported by studies done on both animals and humans, the results of which seem to indicate the existence of separate receptors for starch taste, others than for sweet taste. Starch is a glucose homopolymer that forms an α-glucoside chain called glucosan or glucan. This polysaccharide constitutes the most important source of carbohydrates in food. It can be found in groats, potatoes, legumes, grains, manioc and corn. Apart from its presence in food, starch is also used in textile, pharmaceutical, cosmetic and stationery industries as well as in glue production. This polysaccharide is made of an unbranched helical structure – amylose (15–20%, and a structure that forms branched chains – amylopectin (80–85%. The starch structure, degree of its crystallisation or hydration as well as its availability determine the speed of food-contained starch hydrolysis by amylase. So far, starch has been considered tasteless, but the newest report shows that for people of different origins it is associated with various aliments specific for each culture. Apart from a number of scientific experiments using sweet taste inhibitors, the existence of the sixth taste is also confirmed by molecular studies. However, in order to officially include starch taste to the basic human tastes, it must fulfil certain criteria. The aim of the study is to present contemporary views on starch.
STEFFENS, AB; LEUVENINK, H; SCHEURINK, AJW
Monosodium glutamate (MSG) is used as a food additive to improve the taste of food. The effect of MSG on sweet taste is enhanced by guanosine 5'-monophosphate (GMP). Because increased palatability is known to increase the vagally mediated preabsorptive insulin response (PIR), we hypothesized that
Kinnamon, Sue C.; Finger, Thomas E.
Not only is ATP a ubiquitous source of energy but it is also used widely as an intercellular signal. For example, keratinocytes release ATP in response to numerous external stimuli including pressure, heat, and chemical insult. The released ATP activates purinergic receptors on nerve fibers to generate nociceptive signals. The importance of an ATP signal in epithelial-to-neuronal signaling is nowhere more evident than in the taste system. The receptor cells of taste buds release ATP in response to appropriate stimulation by tastants and the released ATP then activates P2X2 and P2X3 receptors on the taste nerves. Genetic ablation of the relevant P2X receptors leaves an animal without the ability to taste any primary taste quality. Of interest is that release of ATP by taste receptor cells occurs in a non-vesicular fashion, apparently via gated membrane channels. Further, in keeping with the crucial role of ATP as a neurotransmitter in this system, a subset of taste cells expresses a specific ectoATPase, NTPDase2, necessary to clear extracellular ATP which otherwise will desensitize the P2X receptors on the taste nerves. The unique utilization of ATP as a key neurotransmitter in the taste system may reflect the epithelial rather than neuronal origins of the receptor cells. PMID:24385952
Scott, Beth A; Pepper, Ian L
Six waters from different U.S. cities with known diverse taste and odor (TO) evaluations were selected for additional microbial characterization. All waters were subjected to microbial and cultural analyses, and four of the waters were further analyzed by cloning and sequencing of community 16S rRNA. The purpose of the study was to evaluate water distribution systems as living ecosystems, and the impact of these ecosystems on TO. All waters had total bacterial counts of at least 10(3) per ml. The water with lowest TO ranking had 10(6) total counts per ml. Community DNA sequence analysis identified diverse bacterial communities representing five different phyla and over forty genera. Included in this diversity were heterotrophic and autotrophic species that were both aerobic or anaerobic. Additionally, waters with the lowest TO evaluations contained significant sulfide concentrations, as well as bacteria associated with both the oxidation and reduction of inorganic sulfur compounds. Low redox conditions could have resulted in the reduced sulfur compounds and concomitant TO related problems, and an increase in redox could help alleviate these problems. Overall, data show that water distribution systems contain living ecosystems that evolve based on specific environments within particular distribution systems that impact water TO.
Finger, Thomas E
The great number of species of teleosts permits highly specialized forms to evolve to occupy particular niches. This diversity allows for extreme variations in brain structure according to particular sensory or motor adaptations. In the case of the taste system, goldfish (Carassius auratus L., 1758) and some carps have evolved a specialized intraoral food-sorting apparatus along with corresponding specializations of gustatory centers in the brainstem. A comparison of circuitry within the complex vagal lobe of goldfish, and of the simpler gustatory lobes in catfish (Ictalurus punctatus Rafinesque, 1818) shows numerous similarities in organization and neurotransmitters. Double labeling studies using horseradish peroxidase and biotinylated dextran amine in catfish shows a direct projection from the vagal lobe to the motoneurons of nucleus ambiguous which innervate oropharyngeal musculature. Therefore, a three neuron reflex arc connects gustatory input to motor output. In the vagal lobe of goldfish, a similar three neuron arc can be identified: from primary gustatory afferent, to vagal lobe interneuron, thence to dendrites of the vagal motoneurons that innervate the pharyngeal muscles. Therefore, despite large differences in the gross appearance of the vagal gustatory systems in the brains of catfish and goldfish, the essential connectivity and circuitry is similar. This suggests that evolutionary change in the central nervous system largely proceeds by rearrangement and elaboration of existing systems, rather than by addition of new structures or circuits.
Hillersdal, Line; Christensen, Bodil Just; Holm, Lotte
Gastric bypass surgery is a specific medical technology that alters the body in ways that force the patient to fundamentally change his or her eating habits. When patients enrol for surgery, they enter a learning process, encountering new and at times contested ways of sensing their bodies, tasting...
Dunipace, Leslie; Meister, Stephan; McNealy, Corum; Amrein, Hubert
... of seven-transmembrane receptors that are dedicated to olfactory, gustatory, or pheromonal sensory perception [1–11] As in most vertebrates, chemoreception in Drosophila can be divided into two distinct modalities—smell (olfaction), the recognition of volatile molecules, and taste (gustation), the recognition of soluble molecules  . In Dros...
Liu, Dengyong; Li, Shengjie; Wang, Nan; Deng, Yajun; Sha, Lei; Gai, Shengmei; Liu, Huan; Xu, Xinglian
This paper aimed to study the time course changes in taste compounds of Dezhou-braised chicken during the entire cooking process mainly consisting of deep-frying, high-temperature boiling, and low-temperature braising steps. For this purpose, meat samples at different processing stages were analyzed for 5'-nucleotides and free amino acids, and were also subjected to electronic tongue measurements. Results showed that IMP, Glu, Lys, and sodium chloride were the main compounds contributing to the taste attributes of the final product. IMP and Glu increased in the boiling step and remained unchanged in the following braising steps. Meanwhile, decrease in Lys content and increase in sodium chloride content were observed over time in both boiling and braising steps. Intensities for bitterness, saltiness, and Aftertaste-B obtained from the electronic tongue analysis were correlated with the concentrations of these above chemical compounds. Therefore, the electronic tongue system could be applied to evaluate the taste development of Dezhou-braised chicken during processing. © 2017 Institute of Food Technologists®.
Choo, Ezen; Dando, Robin
It is common for women to report a change in taste (for instance an increased bitter or decreased sweet response) during pregnancy, however specifics of any variation in taste with pregnancy remain elusive. Here we review studies of taste in pregnancy, and discuss how physiological changes occurring during pregnancy may influence taste signaling. We aim to consolidate studies of human pregnancy and "taste function" (studies of taste thresholds, discrimination, and intensity perception, rather than hedonic response or self-report), discussing differences in methodology and findings. Generally, the majority of studies report either no change, or an increase in threshold/decrease in perceived taste intensity, particularly in the early stages of pregnancy, suggesting a possible decrease in taste acuity when pregnant. We further discuss several non-human studies of taste and pregnancy that may extend our understanding. Findings demonstrate that taste buds express receptors for many of the same hormones and circulating factors that vary with pregnancy. Circulating gonadal hormones or other contributions from the endocrine system, as well as physiological changes in weight and immune response could all bear some responsibility for such a modulation of taste during pregnancy. Given our growing understanding of taste, we propose that a change in taste function during pregnancy may not be solely driven by hormonal fluctuations of progesterone and estrogen, as many have suggested. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: email@example.com.
Christensen, M; Rasmussen, Verner; Schulze, S
tone during the ERCP was found, but we observed no difference between the metoprolol and the placebo group. For both groups the lowest vagal tone occurred at maximum heart rate during endoscopy. The SDRR/meanRR ratio returned towards base line for the subsequent 60 min after endoscopy. CONCLUSIONS....... During ERCP the patients were monitored with a Holter tape recorder. Holter tapes from 31 patients (16 receiving metoprolol) were available to analyse the ratio of the standard deviations of the RR intervals (SDRR) to the mean RR intervals (measure of vagal tone) during ERCP. RESULTS: A decreased vagal...
Kapsimali, Marika; Barlow, Linda A.
Taste buds are found in a distributed array on the tongue surface, and are innervated by cranial nerves that convey taste information to the brain. For nearly a century, taste buds were thought to be induced by nerves late in embryonic development. However, this view has shifted dramatically. A host of studies now indicate that taste bud development is initiated and proceeds via processes that are nerve-independent, occur long before birth, and governed by cellular and molecular mechanisms intrinsic to the developing tongue. Here we review the state of our understanding of the molecular and cellular regulation of taste bud development, incorporating important new data obtained through the use of two powerful genetic systems, mouse and zebrafish. PMID:23182899
Our senses of taste and smell give us great pleasure. Taste helps us enjoy food and beverages. Smell lets us enjoy the scents and fragrances like roses or coffee. Taste and smell also protect us, letting us know ...
Full Text Available The special sense of taste guides and guards food intake and is essential for body maintenance. Salty and sour tastes are sensed via ion channels or gated ion channels while G protein-coupled receptors (GPCRs of the taste receptor type 1 (T1R family sense sweet and umami tastes and GPCRs of the taste receptor type 2 (T2R family sense bitter tastes. T1R and T2R receptors share similar downstream signaling pathways that result in the stimulation of phospholipase-C-β2. The T1R family includes three members that form heterodimeric complexes to recognize either amino acids or sweet molecules such as glucose. Although these functions were originally described in gustatory tissue, T1R family members are expressed in numerous non-gustatory tissues and are now viewed as nutrient sensors that play important roles in monitoring global glucose and amino acid status. Here, we highlight emerging evidence detailing the function of T1R family members in the musculoskeletal system and review these findings in the context of the musculoskeletal diseases sarcopenia and osteoporosis, which are major public health problems among the elderly that affect locomotion, activities of daily living, and quality of life. These studies raise the possibility that T1R family member function may be modulated for therapeutic benefit.
Damiano, Cara R; Aloi, Joseph; Burrus, Caley; Garbutt, James C; Kampov-Polevoy, Alexei B; Dichter, Gabriel S
The Sweet Taste Test (STT) is a standardized measure designed to index the ability to detect differences in sweet tastes (sweet taste sensitivity) and hedonic responses to sweet tastes (sweet taste liking). Profiles of response on the STT suggest enhanced hedonic responses to sweet tastes in psychiatric disorders characterized by dysfunctional reward processing systems, including binge-eating disorders and substance use disorders, and a putative mechanism governing STT responses is the brain opioid system. The present study examined STT responses in 20 adults with autism spectrum disorder (ASD) and 38 healthy control adults. There were no differences in sweet taste sensitivity or hedonic response to sweet tastes between the ASD and control groups. Within the ASD sample, ASD symptom severity was associated with sweet taste sensitivity, but not hedonic response to sweet taste. Results may ultimately shed light on brain opioid system functioning in ASD.
Shimizu, Madoka; Goto, Masao; Kawai, Takayuki; Yamashita, Atsuko; Kusakabe, Yuko
The sweet taste receptors T1r2 and T1r3 are included in the T1r taste receptor family that belongs to class C of the G protein-coupled receptors. Heterodimerization of T1r2 and T1r3 is required for the perception of sweet substances, but little is known about the mechanisms underlying this heterodimerization, including membrane trafficking. We developed tagged mouse T1r2 and T1r3, and human T1R2 and T1R3 and evaluated membrane trafficking in human embryonic kidney 293 (HEK293) cells. We found that human T1R3 surface expression was only observed when human T1R3 was coexpressed with human T1R2, whereas mouse T1r3 was expressed without mouse T1r2 expression. A domain-swapped chimera and truncated human T1R3 mutant showed that the Venus flytrap module and cysteine-rich domain (CRD) of human T1R3 contain a region related to the inhibition of human T1R3 membrane trafficking and coordinated regulation of human T1R3 membrane trafficking. We also found that the Venus flytrap module of both human T1R2 and T1R3 are needed for membrane trafficking, suggesting that the coexpression of human T1R2 and T1R3 is required for this event. These results suggest that the Venus flytrap module and CRD receive taste substances and play roles in membrane trafficking of human T1R2 and T1R3. These features are different from those of mouse receptors, indicating that human T1R2 and T1R3 are likely to have a novel membrane trafficking system.
Zhi, Ruicong; Cao, Lianyu; Cao, Gang
Growing evidence shows that consumer choices in real life are mostly driven by unconscious mechanisms rather than conscious. The unconscious process could be measured by behavioral measurements. This study aims to apply automatic facial expression analysis technique for consumers' emotion representation, and explore the relationships between sensory perception and facial responses. Basic taste solutions (sourness, sweetness, bitterness, umami, and saltiness) with 6 levels plus water were used, which could cover most of the tastes found in food and drink. The other contribution of this study is to analyze the characteristics of facial expressions and correlation between facial expressions and perceptive hedonic liking for Asian consumers. Up until now, the facial expression application researches only reported for western consumers, while few related researches investigated the facial responses during food consuming for Asian consumers. Experimental results indicated that facial expressions could identify different stimuli with various concentrations and different hedonic levels. The perceived liking increased at lower concentrations and decreased at higher concentrations, while samples with medium concentrations were perceived as the most pleasant except sweetness and bitterness. High correlations were founded between perceived intensities of bitterness, umami, saltiness, and facial reactions of disgust and fear. Facial expression disgust and anger could characterize emotion "dislike," and happiness could characterize emotion "like," while neutral could represent "neither like nor dislike." The identified facial expressions agree with the perceived sensory emotions elicited by basic taste solutions. The correlation analysis between hedonic levels and facial expression intensities obtained in this study are in accordance with that discussed for western consumers. © 2017 Institute of Food Technologists®.
... for Kids? Your Teeth Heart Murmurs What Are Taste Buds? KidsHealth > For Kids > What Are Taste Buds? Print A A A en español ¿Qué ... Did you ever wonder why your favorite foods taste so good? Well, you can thank your taste ...
Ahn, Sae Ryun; An, Ji Hyun; Song, Hyun Seok; Park, Jin Wook; Lee, Sang Hun; Kim, Jae Hyun; Jang, Jyongsik; Park, Tai Hyun
For several decades, significant efforts have been made in developing artificial taste sensors to recognize the five basic tastes. So far, the well-established taste sensor is an E-tongue, which is constructed with polymer and lipid membranes. However, the previous artificial taste sensors have limitations in various food, beverage, and cosmetic industries because of their failure to mimic human taste reception. There are many interactions between tastants. Therefore, detecting the interactions in a multiplexing system is required. Herein, we developed a duplex bioelectronic tongue (DBT) based on graphene field-effect transistors that were functionalized with heterodimeric human umami taste and sweet taste receptor nanovesicles. Two types of nanovesicles, which have human T1R1/T1R3 for the umami taste and human T1R2/T1R3 for the sweet taste on their membranes, immobilized on micropatterned graphene surfaces were used for the simultaneous detection of the umami and sweet tastants. The DBT platform led to highly sensitive and selective recognition of target tastants at low concentrations (ca. 100 nM). Moreover, our DBT was able to detect the enhancing effect of taste enhancers as in a human taste sensory system. This technique can be a useful tool for the detection of tastes instead of sensory evaluation and development of new artificial tastants in the food and beverage industry.
Full Text Available Asystole in a non laparoscopic upper abdominal surgery following intense vagal stimulation is a rare event. This case report highlights the need for awareness of such a complication when a thoracic epidural anaesthetic has been given in addition to a general anaesthetic for an upper abdominal procedure. A combined thoracic epidural and general anaesthetic was given. The anterior abdominal wall was retracted forty minutes after administration of the epidural bolus. This maneuver resulted in a profound vagal response with bradycardia and asystole. The patient was resuscitated successfully with a cardiac massage, atropine and adrenaline and the surgery was resumed. Surgery lasted eleven hours and was uneventful.
Mithril, Charlotte Elisabeth; Kamuk, Anette; Mortensen, Birthe Kofoed
The aim of a so-called research day was to give schoolchildren from 6th to 7th grade a day of learning about taste, sustainability and future foods. The children were invited to University College Absalon in Soroe, Denmark to a day with workshops involving taste experiments. Based on sensory...... experiments related to taste and through involvement and dialogue, the aim was to create knowledge, competences and awareness about taste and to challenge food courage among the children. Focus was to explore taste and taste preferences through sensory experiments and to bring awareness to the taste...... of different foods. In addition, the aim was to create experiences which could show how taste and taste courage are influenced by social interactions and relations. A final aim was to bring awareness of how you can reduce waste with the example of how to use all parts of fruits and vegetables. In total...
Mithril, Charlotte Elisabeth; Kamuk, Anette; Hoffmeyer, Agnete
The aim of a so-called research day was to give schoolchildren from 6th to 7th grade a day of learning about taste, sustainability and future foods. The children were invited to University College Absalon in Soroe, Denmark to a day with workshops involving taste experiments. Based on sensory...... experiments related to taste and through involvement and dialogue, the aim was to create knowledge, competences and awareness about taste and to challenge food courage among the children. Focus was to explore taste and taste preferences through sensory experiments and to bring awareness to the taste...... of different foods. In addition, the aim was to create experiences which could show how taste and taste courage are influenced by social interactions and relations. A final aim was to bring awareness of how you can reduce waste with the example of how to use all parts of fruits and vegetables. In total...
A taste sensor with global selectivity, i. e., electronic tongue, is composed of several kinds of lipid/polymer membranes for transforming information of taste substances into electric signal. The sensor output shows different patterns for chemical substances which have different taste qualities such as saltiness and sourness. Taste interactions such as suppression effect, which occurs between bitterness and sweetness, can be detected and quantified using the taste sensor. Amino acids can be classified into several groups according to their own tastes from sensor outputs. The taste of foodstuffs such as beer, coffee, mineral water and milk can be discussed quantitatively. The taste sensor provides the objective scale for the human sensory expression. We are now standing at the beginning of a new age of communication using digitized taste.
Among the five senses, taste and olfaction play crucial roles in the detection of chemical substances in the environment and are referred to as chemical senses. In the past decade, much progress has been made in studies on molecular mechanisms of the gustatory system by methods such as those based on molecular and cellular biology, genetics, and bioinformatics. This review covers recent studies on taste receptors, intracellular signaling transduction in taste receptor cells, and taste coding at the periphery in vertebrates from fish to mammals.
Frøkjaer, J B; Bergmann, S; Brock, C
, using transcutaneous electrical vagal nerve stimulation (t-VNS) and deep slow breathing (DSB) respectively, could increase musculoskeletal pain thresholds and enhance gastroduodenal motility in healthy subjects. METHODS: Eighteen healthy subjects were randomized to a subject-blinded, sham......-controlled, cross-over study with an active protocol including stimulation of auricular branch of the vagus nerve, and breathing at full inspiratory capacity and forced full expiration. Recording of cardiac derived parameters including cardiac vagal tone, moderate pain thresholds to muscle, and bone pressure......BACKGROUND: The parasympathetic nervous system, whose main neural substrate is the vagus nerve, exerts a fundamental antinociceptive role and influences gastrointestinal sensori-motor function. Our research question was to whether combined electrical and physiological modulation of vagal tone...
Bachmanov Alexander A
Full Text Available Abstract This review focuses on behavioral genetic studies of sweet, umami, bitter and salt taste responses in mammals. Studies involving mouse inbred strain comparisons and genetic analyses, and their impact on elucidation of taste receptors and transduction mechanisms are discussed. Finally, the effect of genetic variation in taste responsiveness on complex traits such as drug intake is considered. Recent advances in development of genomic resources make behavioral genetics a powerful approach for understanding mechanisms of taste.
Yarmolinsky, David A; Zuker, Charles S; Ryba, Nicholas J P
The sense of taste is a specialized chemosensory system dedicated to the evaluation of food and drink. Despite the fact that vertebrates and insects have independently evolved distinct anatomic and molecular pathways for taste sensation, there are clear parallels in the organization and coding logic between the two systems. There is now persuasive evidence that tastant quality is mediated by labeled lines, whereby distinct and strictly segregated populations of taste receptor cells encode each of the taste qualities.
Vijay Kumar Ambaldhage
Full Text Available For maintenance of the health of an individual, taste sensation is very important. It is an important sensation that serves to assess the nutritious content of food, support oral intake, and prevent ingestion of potentially toxic substances. Disturbances in the perception of taste can lead to loss of appetite, causing malnutrition and thus distressing both the physical and psychological well-being of the patient. Oral physicians are often the first clinicians who hear complaints about alteration in taste from the patients. In spite of the effect of taste changes on health, literature on the diagnosis, pathogenesis, and precise treatment of taste disorders are less. Taste changes may lead patients to seek inappropriate dental treatments. Proper diagnosis of the etiology is the foremost step in the treatment of taste disorders. Thus, it is important that dental clinicians to be familiar with the various causes and proper management of taste changes. In this article, we have reviewed related articles focusing on taste disorders and their management, to provide a quick sketch for the clinicians. A detailed search was performed to identify the systematic reviews and research articles on taste disorders, using PUBMED and Cochrane. All the authors independently extracted data for analysis and review. Ultimately, 26 articles underwent a full text review. In conclusion, the research to date certainly offers us valid management strategies for taste disorders. Meanwhile, practical strategies with the highest success are needed for further intervention.
In mammals, the sense of taste helps in the evaluation and consumption of nutrients, and in avoiding toxic substances and indigestible materials. Distinct cell types expressing unique receptors detect each of the five basic tastes: salty, sour, bitter, sweet and umami. The latter three tastes are detected by two distinct families of G protein-coupled receptors: T2Rs and T1Rs. Interestingly, these taste receptors have been found in tissues other than the tongue, such as the digestive system, respiratory system, brain, testis and spermatozoa. The functional implications of taste receptors distributed throughout the body are unknown. We therefore reviewed the remarkable advances in our understanding of the molecular basis of taste perception in 'taste' and 'non-taste' tissues. We also present our speculations on the direction of further research in the field of male reproduction.
Miura, Hirohito; Barlow, Linda A.
SUMMARY While the taste periphery has been studied for over a century, we are only beginning to understand how this important sensory system is maintained throughout adult life. With the advent of molecular genetics in rodent models, and the upswing in translational approaches that impact human patients, we expect the field will make significant advances in the near future. PMID:20830973
Pijacka, Wioletta; Clifford, Bethan; Walas, Dawid; Tilburgs, Chantal; Joles, Jaap A; McMullen, Sarah; Langley-Evans, Simon C
OBJECTIVE: It is well established that autonomic nervous system and sympatho-vagal balance plays an important role in maintaining arterial blood pressure (ABP) (Salman IM., 2016) and that autonomic regulation of ABP differs between males and females (Hart EC et al., 2014). We hypothesised that sex
We conducted taste profile analysis of white ginseng (Panax ginseng) using a taste-sensing system. Taste such as sourness, bitterness, astringent, aftertaste, umami, richness, and saltiness of the four subfractions (n-hexane fr. = Pg1; EtOAc fr. = Pg2; CHCl3 fr. = Pg3; n-BuOH fr. = Pg4) from white ginseng was checked using ...
In this paper, empirical studies on taste cells and the results of potential changes related to sour taste are used, and by studying the messages transmitted by the nervous system and equivalent sample signal of this taste, mathematical equations related to these changes are obtained, and by designing a microcontroller ...
Jul 8, 2014 ... Taste allows the fly to evaluate potential food sources. The presence of nutritious sugars, which taste sweet, and toxins, which taste bitter, is detected by gustatory organs. Their input is integrated in the CNS and provides a basis for feeding decisions. Drosophila is a valuable system in which to investigate ...
Bandyopadhyay, Prasun; Ghosh, Amit K; Ghosh, Chandrasekhar
Tea and coffee are widely consumed beverages across the world and they are rich sources of various polyphenols. Polyphenols are responsible for the bitterness and astringency of beverages and are also well known to impart antioxidant properties which is beneficial against several oxidative stress related diseases like cancer, cardiovascular diseases, and aging. On the other hand, proteins are also known to display many important roles in several physiological activities. Polyphenols can interact with proteins through hydrophobic or hydrophilic interactions, leading to the formation of soluble or insoluble complexes. According to recent studies, this complex formation can affect the bioavailability and beneficiary properties of both the individual components, in either way. For example, polyphenol-protein complex formation can reduce or enhance the antioxidant activity of polyphenols; similarly it can also affect the digestion ability of several digestive enzymes present in our body. Surprisingly, no review article has been published recently which has focused on the progress in this area, despite numerous articles having appeared in this field. This review summarizes the recent trends and patterns (2005 onwards) in polyphenol-protein interaction studies focusing on the characterization of the complex, the effect of this complex formation on tea and coffee taste, antioxidant properties and the digestive system.
Andrew M Rosen
Full Text Available To qualify as a basic taste quality or modality, defined as a group of chemicals that taste alike, three empirical benchmarks have commonly been used. The first is that a candidate group of tastants must have a dedicated transduction mechanism in the peripheral nervous system. The second is that the tastants evoke physiological responses in dedicated afferent taste nerves innervating the oropharyngeal cavity. Last, the taste stimuli evoke activity in central gustatory neurons, some of which may respond only to that group of tastants. Here we argue that water may also be an independent taste modality. This argument is based on the identification of a water dedicated transduction mechanism in the peripheral nervous system, water responsive fibers of the peripheral taste nerves and the observation of water responsive neurons in all gustatory regions within the central nervous system. We have described electrophysiological responses from single neurons in nucleus of the solitary tract (NTS and parabrachial nucleus of the pons (PbN, respectively the first two central relay nuclei in the rodent brainstem, to water presented as a taste stimulus in anesthetized rats. Responses to water were in some cases as robust as responses to other taste qualities and sometimes occurred in the absence of responses to other tastants. Both excitatory and inhibitory responses were observed. Also, the temporal features of the water response resembled those of other taste responses. We argue that water may constitute an independent taste modality that is processed by dedicated neural channels at all levels of the gustatory neuraxis. Water-dedicated neurons in the brainstem may constitute key elements in the regulatory system for fluid in the body, i.e. thirst, and as part of the swallowing reflex circuitry.
Scott, Brandon G.; Weems, Carl F.
This study tested the associations of both resting vagal tone and vagal response to stress with anxiety control beliefs, anxiety, and aggression among 80 youth (aged 11-17 years). Measures included physiological assessments of emotion regulation along with youth self-report of anxiety control beliefs, anxiety, and aggression and caregiver reports of their child's anxiety and aggression. Resting vagal tone was positively related to anxiety control beliefs, but negatively associated with anxiet...
de Brito Sanchez, Gabriela; Giurfa, Martin
Understanding taste processing in the nervous system is a fundamental challenge of modern neuroscience. Recent research on the neural bases of taste coding in invertebrates and vertebrates allows discussion of whether labelled-line or across-fibre pattern encoding applies to taste perception. While the former posits that each gustatory receptor responds to one stimulus or a very limited range of stimuli and sends a direct ‘line’ to the central nervous system to communicate taste information, the latter postulates that each gustatory receptor responds to a wider range of stimuli so that the entire population of taste-responsive neurons participates in the taste code. Tastes are represented in the brain of the fruitfly and of the rat by spatial patterns of neural activity containing both distinct and overlapping regions, which are in accord with both labelled-line and across-fibre pattern processing of taste, respectively. In both animal models, taste representations seem to relate to the hedonic value of the tastant (e.g. palatable versus non-palatable). Thus, although the labelled-line hypothesis can account for peripheral taste processing, central processing remains either unknown or differs from a pure labelled-line coding. The essential task for a neuroscience of taste is, therefore, to determine the connectivity of taste-processing circuits in central nervous systems. Such connectivity may determine coding strategies that differ significantly from both the labelled-line and the across-fibre pattern models. PMID:21690133
Full Text Available Gustatory novelty ‘detection requires the comparison between on line sensorial information and off line information, i.e. memory; from there a cascade of events is trigger when a maladjustment between these situations is detected. This process require neuromodulator´s pathways, which involved several systems in different cerebral areas acting in parallel, modulating the gene expression, and at last altering the cortical pathways which encode the new information. The acquisition of this information can be study through different experimental procedures, in which the associations between the gustatory stimuli and the gastrointestinal consequences are evaluated. The main evidences in rodents of the neurotransmission systems mostly involved in the flavor memory, for the appetitive and aversive memories are revised in this work.
Takeuchi, Yoshiko; Usui, Rina; Ikezaki, Hidekazu; Tahara, Kohei; Takeuchi, Hirofumi
Taste detection systems using electronic sensors are needed in the field of pharmaceutical design. The aim of this study was to propose an advanced technique using a taste-sensing system to evaluate the bitterness of an orally disintegrating film (ODF) samples. In this system, a solid film sample is kept in the test medium with stirring, and the sensor output is recorded. Model films were prepared using a solution-casting method with a water-soluble polymer such as pullulan, HPMC, HPC or PVP as film formers, and donepezil hydrochloride and quinine hydrochloride as model bitter-tasting active pharmaceutical ingredients (APIs). The results showed that this advanced techniques could detect the emergence of bitterness along the time course. Increasing the amount of donepezil hydrochloride increased the sensor output. The sensor output was suppressed at the very early stage of the test, and then increased. Both the film thickness and the use of additives markedly affected the delay of the sensor output. The profile of the sensor output was accurately related to the release of APIs. It was concluded that this advanced technique could detect the onset of bitterness during the initial stage of ODF administration. Copyright © 2017 Elsevier B.V. All rights reserved.
Lemon, Christian H
Taste stimuli have a temperature that can stimulate thermosensitive neural machinery in the mouth during gustatory experience. Although taste and oral temperature are sometimes discussed as different oral sensory modalities, there is a body of literature that demonstrates temperature is an important component and modulator of the intensity of gustatory neural and perceptual responses. Available data indicate that the influence of temperature on taste, herein referred to as "thermogustation," can vary across taste qualities, can also vary among stimuli presumed to share a common taste quality, and is conditioned on taste stimulus concentration, with neuronal and psychophysical data revealing larger modulatory effects of temperature on gustatory responding to weakened taste solutions compared with concentrated. What is more, thermogustation is evidenced to involve interplay between mouth and stimulus temperature. Given these and other dependencies, identifying principles by which thermal input affects gustatory information flow in the nervous system may be important for ultimately unravelling the organization of neural circuits for taste and defining their involvement with multisensory processing related to flavor. Yet thermal effects are relatively understudied in gustatory neuroscience. Major gaps in our understanding of the mechanisms and consequences of thermogustation include delineating supporting receptors, the potential involvement of oral thermal and somatosensory trigeminal neurons in thermogustatory interactions, and the broader operational roles of temperature in gustatory processing. This review will discuss these and other issues in the context of the literature relevant to understanding thermogustation. Copyright © 2017 the American Physiological Society.
Gravina, Stephen A; Yep, Gregory L; Khan, Mehmood
Taste or gustation is one of the 5 traditional senses including hearing, sight, touch, and smell. The sense of taste has classically been limited to the 5 basic taste qualities: sweet, salty, sour, bitter, and umami or savory. Advances from the Human Genome Project and others have allowed the identification and determination of many of the genes and molecular mechanisms involved in taste biology. The ubiquitous G protein-coupled receptors (GPCRs) make up the sweet, umami, and bitter receptors. Although less clear in humans, transient receptor potential ion channels are thought to mediate salty and sour taste; however, other targets have been identified. Furthermore, taste receptors have been located throughout the body and appear to be involved in many regulatory processes. An emerging interplay is revealed between chemical sensing in the periphery, cortical processing, performance, and physiology and likely the pathophysiology of diseases such as diabetes.
This thesis presents an ethnographic investigation into practices of tasting. Based on ethnographic fieldwork in various Western Europe settings in which people sensually engaged with food and drinks, the chapters show how tasting is done by research subjects in sensory science laboratories; guests...... in a restaurant; medical professionals and patients in a hospital; and people gathered for a wine tasting event, daily dinner or a meal in a convent. The ethnographic materials are used to engage with what so far social science literatures on tasting tend to take for granted: that tasting is a physiological...... particular practices, the chapters unpack each of these assumptions. What emerges is an alternative, composite understanding of tasting as variously done in varied mundane practices....
Zila, I; Mokra, D; Kopincova, J; Kolomaznik, M; Javorka, M; Calkovska, A
Inflammation and other immune responses are involved in the variety of diseases and disorders. The acute response to endotoxemia includes activation of innate immune mechanisms as well as changes in autonomic nervous activity. The autonomic nervous system and the inflammatory response are intimately linked and sympathetic and vagal nerves are thought to have anti-inflammation functions. The basic functional circuit between vagus nerve and inflammatory response was identified and the neuroimmunomodulation loop was called cholinergic anti-inflammatory pathway. Unique function of vagus nerve in the anti-inflammatory reflex arc was found in many experimental and pre-clinical studies. They brought evidence on the cholinergic signaling interacting with systemic and local inflammation, particularly suppressing immune cells function. Pharmacological/electrical modulation of vagal activity suppressed TNF-alpha and other proinflammatory cytokines production and had beneficial therapeutic effects. Many questions related to mapping, linking and targeting of vagal-immune interactions have been elucidated and brought understanding of its basic physiology and provided the initial support for development of Tracey´s inflammatory reflex. This review summarizes and critically assesses the current knowledge defining cholinergic anti-inflammatory pathway with main focus on studies employing an experimental approach and emphasizes the potential of modulation of vagally-mediated anti-inflammatory pathway in the treatment strategies.
Brock, C; Brock, B; Aziz, Q
-VNS, there was an increase in cardiac vagal tone and a reduction in tumor necrosis factor-α in comparison to baseline. No change was seen in blood pressure, cardiac sympathetic index or other cytokines. These preliminary data suggest that t-VNS exerts an autonomic and a subtle antitumor necrosis factor-α effect, which...
Gianaros, P.J.; Graham, R.; Somsen, R.J.M.; van der Molen, M.W.; Jennings, J.R.
The integration of behavioral processes with changes in vagally-controlled heart rate has been the focus of our investigations. A series of studies is reviewed showing that central and peripheral response inhibition is a primary source of transient, vagally-induced cardiac slowing during information
Miller, Jonas G.; Kahle, Sarah; Hastings, Paul D.
Vagal tone is widely believed to be an important physiological aspect of emotion regulation and associated positive behaviors. However, there is inconsistent evidence for relations between children's baseline vagal tone and their helpful or prosocial responses to others (Hastings & Miller, 2014). Recent work in adults suggests a quadratic…
Schmidt, P; Poulsen, Steen Seier; Hilsted, L
Electrical vagal stimulation activates both stimulatory and inhibitory nerve fibers regulating gastrin release in the porcine antrum. The aim of this study was to examine the role of tachykinins in the inhibitory vagal control of gastrin release in the porcine antrum....
Besnard, Philippe; Passilly-Degrace, Patricia; Khan, Naim A
An attraction for palatable foods rich in lipids is shared by rodents and humans. Over the last decade, the mechanisms responsible for this specific eating behavior have been actively studied, and compelling evidence implicates a taste component in the orosensory detection of dietary lipids [i.e., long-chain fatty acids (LCFA)], in addition to textural, olfactory, and postingestive cues. The interactions between LCFA and specific receptors in taste bud cells (TBC) elicit physiological changes that affect both food intake and digestive functions. After a short overview of the gustatory pathway, this review brings together the key findings consistent with the existence of a sixth taste modality devoted to the perception of lipids. The main steps leading to this new paradigm (i.e., chemoreception of LCFA in TBC, cell signaling cascade, transfer of lipid signals throughout the gustatory nervous pathway, and their physiological consequences) will be critically analyzed. The limitations to this concept will also be discussed in the light of our current knowledge of the sense of taste. Finally, we will analyze the recent literature on obesity-related dysfunctions in the orosensory detection of lipids ("fatty" taste?), in relation to the overconsumption of fat-rich foods and the associated health risks. Copyright © 2016 the American Physiological Society.
Mesz, Bruno; Trevisan, Marcos A; Sigman, Mariano
Zarlino, one of the most important music theorists of the XVI century, described the minor consonances as 'sweet' (dolci) and 'soft' (soavi) (Zarlino 1558/1983, in On the Modes New Haven, CT: Yale University Press, 1983). Hector Berlioz, in his Treatise on Modern Instrumentation and Orchestration (London: Novello, 1855), speaks about the 'small acid-sweet voice' of the oboe. In line with this tradition of describing musical concepts in terms of taste words, recent empirical studies have found reliable associations between taste perception and low-level sound and musical parameters, like pitch and phonetic features. Here we investigated whether taste words elicited consistent musical representations by asking trained musicians to improvise on the basis of the four canonical taste words: sweet, sour, bitter, and salty. Our results showed that, even in free improvisation, taste words elicited very reliable and consistent musical patterns:'bitter' improvisations are low-pitched and legato (without interruption between notes), 'salty' improvisations are staccato (notes sharply detached from each other), 'sour' improvisations are high-pitched and dissonant, and 'sweet' improvisations are consonant, slow, and soft. Interestingly, projections of the improvisations of taste words to musical space (a vector space defined by relevant musical parameters) revealed that, in musical space, improvisations based on different taste words were nearly orthogonal or opposite. Decoding methods could classify binary choices of improvisations (i.e., identify the improvisation word from the melody) at performance of around 80%--well above chance. In a second experiment we investigated the mapping from perception of music to taste words. Fifty-seven non-musical experts listened to a fraction of the improvisations. We found that listeners classified with high performance the taste word which had elicited the improvisation. Our results, furthermore, show that associations of taste and music
Liccardi, Gennaro; Salzillo, Antonello; Calzetta, Luigino; Cazzola, Mario; Matera, Maria Gabriella; Rogliani, Paola
Recently, we studied occurrence and role of non-respiratory symptoms (n-RSs) before a worsening of asthma symptoms. Some n-RSs such as anxiety, reflux, heartburn, abdominal pain, which appeared within 3 h before the onset of an asthma attack, are the likely result of an imbalance between sympathetic/parasympathetic systems with an increase in cholinergic tone. Therefore, it is likely that some of these n-RSs induced by the increased cholinergic tone might be present related with specific parasympathetic-associated respiratory symptoms such as those elicited by airway narrowing. It is likely that, at least in some categories of asthmatics, an increased cholinergic tone, rather than other well-known factors, might play a prevalent role in triggering bronchospasm. If this is the case, it is possible to speculate that the use of anticholinergic agents (mainly those with long-acting activity) in patients suffering from asthma should be more beneficial in individuals characterized by a higher degree of cholinergic tone that, consequently might be the ideal target for the use of long-acting anticholinergics and, possibly, represent a novel asthma phenotype. The presence of parasympathetic-associated n-RSs might help the physician to identify this type of patients, although this might be followed by a more detailed assessment. Copyright © 2016 Elsevier Ltd. All rights reserved.
Spector, Alan C; Blonde, Ginger; Garcea, Mircea; Jiang, Enshe
Forty years have passed since it was demonstrated that a cross-regenerated gustatory nerve in the rat tongue adopts the stimulus-response properties of the taste receptor field it cross-reinnervates. Nevertheless, the functional consequences of channeling peripheral taste signals through inappropriate central circuits remain relatively unexplored. Here we tested whether histologically confirmed cross-regeneration of the chorda tympani nerve (CT) into the posterior tongue in the absence of the glossopharyngeal nerve (GL) (CT-PostTongue) or cross-regeneration of the GL into the anterior tongue in the absence of the CT (GL-AntTongue) would maintain presurgically trained performance in an operant NaCl vs. KCl taste discrimination task in rats. Before surgery all groups were averaging over 90% accuracy. Oral amiloride treatment dropped performance to virtually chance levels. During the first week after surgery, sham-operated rats, GL-transected rats, and rats with regenerated CTs displayed highly competent discrimination performance. In contrast, CT-transected rats were severely impaired (59% accuracy). Both the CT-PostTongue and the GL-AntTongue groups were impaired to a similar degree as CT-transected rats. These initially impaired groups improved their performance over the weeks of postsurgical testing, suggesting that the rats were capable of relearning the task with discriminable signals in the remaining taste nerves. This relearned performance was dependent on input from amiloride-sensitive receptors likely in the palate. Overall, these results suggest that normal competence in a salt discrimination task is dependent on the taste receptor field origin of the input as well as the specific nerve transmitting the signals to its associated circuits in the brain. Copyright 2009 Elsevier B.V. All rights reserved.
Masek, Pavel; Keene, Alex C
Taste allows animals to discriminate the value and potential toxicity of food prior to ingestion. Many tastants elicit an innate attractive or avoidance response that is modifiable with nutritional state and prior experience. A powerful genetic tool kit, well-characterized gustatory system, and standardized behavioral assays make the fruit fly, Drosophila melanogaster, an excellent system for investigating taste processing and memory. Recent studies have used this system to identify the neural basis for acquired taste preference. These studies have revealed a role for dopamine-mediated plasticity of the mushroom bodies that modulate the threshold of response to appetitive tastants. The identification of neural circuitry regulating taste memory provides a system to study the genetic and physiological processes that govern plasticity within a defined memory circuit.
Evans, Joshua David; Flore, Roberto; Pedersen, Jonas Astrup
taste, generating and adapting practical ideas and methods for those who make food and those who enjoy eating. This paper describes some of our methods, using geography as a starting point for the exploration of deliciousness, exemplified in our lunch menu served at the Science of Taste symposium...
Recent research in sociology of art indicates an increasing heterogeneity and openness in cultural taste and consumption. This tendency also appears to be sanctified by developments in the arts and aesthetic theory of the last decades. Compared to former more exclusive and elitist cultures of taste...
de Groot, Mark C H; van Puijenbroek, Eugène P
AIMS: Topical use of clindamycin has been associated with taste disorders in the literature, but little is known about the nature of this adverse drug reaction. The aim of this article was to describe reports of clindamycin-induced taste disorders and to analyse the factors involved. METHODS: The
.... The book is conveniently divided into sections, including linguistic representations, emotion, memory, neural bases, and individual variation. Leading experts have written chapters on many facets of taste and smell, including odor memory, cortical representations, psychophysics and functional imaging studies, genetic variation in taste, and ...
Karl Juergen Bär
Full Text Available AbstractRegular physical exercise leads increased vagal modulation of the cardiovascular system. A combination of peripheral and central processes has been proposed to underlie this adaptation. However, specific changes in the central autonomic network have not been described in human in more detail. We hypothesized that the anterior hippocampus known to be influenced by regular physical activity might be involved in the development of increased vagal modulation after a 6 weeks high intensity intervention in young healthy men (exercise group: n=17, control group: n=17. In addition to the determination of physical capacity before and after the intervention, we used resting state functional magnetic resonance imaging and synchronic heart rate variability assessment.We detected a significant increase of the power output at the anaerobic threshold of 11.4% (p<0.001, the maximum power output Pmax of 11.2% (p<0.001, and VO2max adjusted for body weight of 4.7% (p<0.001 in the exercise group (EG. Comparing baseline (T0 and post-exercise (T1 values of parasympathetic modulation of the exercise group, we observed a trend for a decrease in heart rate (p<0.06 and a significant increase of vagal modulation as indicated by RMSSD (p<0.026 during resting state. In the whole brain analysis, we found that the connectivity pattern of the right anterior hippocampus (aHC was specifically altered to the ventromedial anterior cortex, the dorsal striatum and to the dorsal vagal complex (DVC in the brainstem. Moreover, we only observed a highly significant negative correlation between increased RMSSD after exercise and decreased functional connectivity from the right aHC to DVC (r=-0.69, p=0.003. This indicates that increased vagal modulation was associated with functional connectivity between aHC and the dorsal vagal complex.In conclusion, our findings suggest that exercise associated changes in anterior hippocampal function might be involved in increased vagal
Joshi, Kalpana; Hankey, Alex; Patwardhan, Bhushan
Ayurveda, the system of traditional medicine from India, holds that ‘Rasa’, a concept roughly corresponding to taste, is a basis for identifying pharmacological properties of plants and other materia medica used in Dravyaguna—its system of phytomedicine. This idea has recently found support in studies of ibuprofen, the pharmacological properties of which are similar to those of oleocanthal, because the two substances have very similar tastes. This paper discusses a possible scientific approac...
Bär, Karl-Jürgen; Herbsleb, Marco; Schumann, Andy; de la Cruz, Feliberto; Gabriel, Holger W.; Wagner, Gerd
Regular physical exercise leads to increased vagal modulation of the cardiovascular system. A combination of peripheral and central processes has been proposed to underlie this adaptation. However, specific changes in the central autonomic network have not been described in human in more detail. We hypothesized that the anterior hippocampus known to be influenced by regular physical activity might be involved in the development of increased vagal modulation after a 6 weeks high intensity intervention in young healthy men (exercise group: n = 17, control group: n = 17). In addition to the determination of physical capacity before and after the intervention, we used resting state functional magnetic resonance imaging and simultaneous heart rate variability assessment. We detected a significant increase of the power output at the anaerobic threshold of 11.4% (p exercise group (EG). Comparing baseline (T0) and post-exercise (T1) values of parasympathetic modulation of the exercise group, we observed a trend for a decrease in heart rate (p brain analysis, we found that the connectivity pattern of the right anterior hippocampus (aHC) was specifically altered to the ventromedial anterior cortex, the dorsal striatum and to the dorsal vagal complex (DVC) in the brainstem. Moreover, we observed a highly significant negative correlation between increased RMSSD after exercise and decreased functional connectivity from the right aHC to DVC (r = −0.69, p = 0.003). This indicates that increased vagal modulation was associated with functional connectivity between aHC and the DVC. In conclusion, our findings suggest that exercise associated changes in anterior hippocampal function might be involved in increased vagal modulation. PMID:27092046
Kinnamon, Sue C
l-Glutamate elicits the umami taste sensation, now recognized as a fifth distinct taste quality. A characteristic feature of umami taste is its potentiation by 5'-ribonucleotides such as guanosine-5'-monophosphate and inosine 5'-monophosphate, which also elicit the umami taste on their own. Recent data suggest that multiple G protein-coupled receptors contribute to umami taste. This review will focus on events downstream of the umami taste receptors. Ligand binding leads to Gbetagamma activation of phospholipase C beta2, which produces the second messengers inositol trisphosphate and diacylglycerol. Inositol trisphosphate binds to the type III inositol trisphosphate receptor, which causes the release of Ca(2+) from intracellular stores and Ca(2+)-dependent activation of a monovalent-selective cation channel, TRPM5. TRPM5 is believed to depolarize taste cells, which leads to the release of ATP, which activates ionotropic purinergic receptors on gustatory afferent nerve fibers. This model is supported by knockout of the relevant signaling effectors as well as physiologic studies of isolated taste cells. Concomitant with the molecular studies, physiologic studies show that l-glutamate elicits increases in intracellular Ca(2+) in isolated taste cells and that the source of the Ca(2+) is release from intracellular stores. Both Galpha gustducin and Galpha transducin are involved in umami signaling, because the knockout of either subunit compromises responses to umami stimuli. Both alpha-gustducin and alpha-transducin activate phosphodiesterases to decrease intracellular cAMP. The target of cAMP in umami transduction is not known, but membrane-permeant analogs of cAMP antagonize electrophysiologic responses to umami stimuli in isolated taste cells, which suggests that cAMP may have a modulatory role in umami signaling.
The paper presents an idea of developing taste sensors using novel printed sensors. The raw materials used for developing the sensors were commercial polymer films. Powered graphene was produced using laser induction technique. This powder was separately transferred to Kapton tapes to developed flexible graphene sensors. The fabricated sensors were tested with different chemicals having specific attributes with the idea to develop a taste sensor. Three different types of chemicals were tested and analyzed to verify the ability of the developed sensor patch to differentiate between the individual chemicals. The initial results have provided a significant platform in the process of developing a fully functionalized taste sensing system.
Travagli, R Alberto; Hermann, Gerlinda E; Browning, Kirsteen N; Rogers, Richard C
Vago-vagal reflex circuits modulate digestive functions from the oral cavity to the transverse colon. Previous articles in this series have described events at the level of the sensory receptors encoding the peripheral stimuli, the transmission of information in the afferent vagus, and the conversion of this data within the dorsal vagal complex (DVC) to impulses in the preganglionic efferents. The control by vagal efferents of the postganglionic neurons impinging on the glands and smooth muscles of the target organs has also been illustrated. Here we focus on some of the mechanisms by which these apparently static reflex circuits can be made quite plastic as a consequence of the action of modulatory inputs from other central nervous system sources. A large body of evidence has shown that the neuronal elements that constitute these brain stem circuits have nonuniform properties and function differently according to status of their target organs and the level of activity in critical modulatory inputs. We propose that DVC circuits undergo a certain amount of short-term plasticity that allows the brain stem neuronal elements to act in harmony with neural systems that control behavioral and physiological homeostasis.
Full Text Available Bitter taste is serous and very often cheese failure in modern cheesemaking process. In this paper the sources and bitter taste development in cheese will be presented. Bitterness in cheese is linked to bitter compounds development during cheese ripening. Most of the bitter compounds come from bitter peptides, the mechanism of theirs development being due to proteasepeptidase system of the cured enzymes and the milk cultures as well as other proteases present in cheese. By the action of curd enzymes, the milk protein - casein - is firstly degraded into high molecular weight compounds possessing no bitter taste. Those compounds are then degraded, by milk protease cultures, to hydrophobic bitter peptides of low molecular weight further degraded, by bacterial endopeptidase during cheese ripening, to bitter peptides and amino acids. In the case when no balance exists, between bitter compounds development and breakdown by lactic acid bacteria peptidase, an accumulation of bitter peptides occurs thus having an influence on cheese bitterness. During cheese ripening naturally occurring milk protease – plasmin, and thermostable proteases of raw milk microflora are also involved in proteolytic process. Fat cheese lipases, initiated by lipase originating from psychrotrophic bacteria in raw milk as well as other cheese lipases, are also associated with bitter taste generation. The other sources of bitterness come from the forages, the medicament residues as well as washing and disinfecting agents. In order to eliminate these failures a special care should be taken in milk quality as well as curd and milk culture selection. At this point technological norms and procedures, aimed to maintain the proteolysis balance during cheese ripening, should be adjusted, thus eliminating the bitter taste of the cheese.
Targeted taste cell-specific overexpression of brain-derived neurotrophic factor in adult taste buds elevates phosphorylated TrkB protein levels in taste cells, increases taste bud size, and promotes gustatory innervation.
Nosrat, Irina V; Margolskee, Robert F; Nosrat, Christopher A
Brain-derived neurotrophic factor (BDNF) is the most potent neurotrophic factor in the peripheral taste system during embryonic development. It is also expressed in adult taste buds. There is a lack of understanding of the role of BDNF in the adult taste system. To address this, we generated novel transgenic mice in which transgene expression was driven by an α-gustducin promoter coupling BDNF expression to the postnatal expression of gustducin in taste cells. Immunohistochemistry revealed significantly stronger BDNF labeling in taste cells of high BDNF-expressing mouse lines compared with controls. We show that taste buds in these mice are significantly larger and have a larger number of taste cells compared with controls. To examine whether innervation was affected in Gust-BDNF mice, we used antibodies to neural cell adhesion molecule (NCAM) and ATP receptor P2X3. The total density of general innervation and specifically the gustatory innervation was markedly increased in high BDNF-expressing mice compared with controls. TrkB and NCAM gene expression in laser capture microdissected taste epithelia were significantly up-regulated in these mice. Up-regulation of TrkB transcripts in taste buds and elevated taste cell-specific TrkB phosphorylation in response to increased BDNF levels indicate that BDNF controls the expression and activation of its high affinity receptor in taste cells. This demonstrates a direct taste cell function for BDNF. BDNF also orchestrates and maintains taste bud innervation. We propose that the Gust-BDNF transgenic mouse models can be employed to further dissect the specific roles of BDNF in the adult taste system.
Joshi, Kalpana; Hankey, Alex; Patwardhan, Bhushan
Ayurveda, the system of traditional medicine from India, holds that 'Rasa', a concept roughly corresponding to taste, is a basis for identifying pharmacological properties of plants and other materia medica used in Dravyaguna-its system of phytomedicine. This idea has recently found support in studies of ibuprofen, the pharmacological properties of which are similar to those of oleocanthal, because the two substances have very similar tastes. This paper discusses a possible scientific approach to understanding the Ayurvedic (hypo)thesis in terms of the stereochemical basis of both pharamaco-activity and taste, and the numbers of possible pharmaco-active compounds that 'Rasa' may be able to distinguish. We conclude that molecules binding to a specific enzyme active site should have their own 'Rasa', and that the number of different subjectively experienced 'tastes' is more than enough to distinguish between molecular shapes binding to all enzyme active sites in the body.
Sturge-Apple, Melissa L; Suor, Jennifer H; Davies, Patrick T; Cicchetti, Dante; Skibo, Michael A; Rogosch, Fred A
Children from different socioeconomic backgrounds have differing abilities to delay gratification, and impoverished children have the greatest difficulties in doing so. In the present study, we examined the role of vagal tone in predicting the ability to delay gratification in both resource-rich and resource-poor environments. We derived hypotheses from evolutionary models of children's conditional adaptation to proximal rearing contexts. In Study 1, we tested whether elevated vagal tone was associated with shorter delay of gratification in impoverished children. In Study 2, we compared the relative role of vagal tone across two groups of children, one that had experienced greater impoverishment and one that was relatively middle-class. Results indicated that in resource-rich environments, higher vagal tone was associated with longer delay of gratification. In contrast, high vagal tone in children living in resource-poor environments was associated with reduced delay of gratification. We interpret the results with an eye to evolutionary-developmental models of the function of children's stress-response system and adaptive behavior across varying contexts of economic risk. © The Author(s) 2016.
Sturge-Apple, Melissa L.; Suor, Jennifer H.; Davies, Patrick T.; Cicchetti, Dante; Skibo, Michael A.; Rogosch, Fred A.
Socioeconomic disparities in children’s delay of gratification exist, with impoverished children displaying greater difficulties in this developmental domain. The present paper examined the role of vagal tone in predicting the ability to delay gratification across resource rich and resource poor environments. Embedding hypotheses within evolutionary models of children’s conditional adaptation to proximal rearing contexts, Study 1 tested whether elevated vagal tone was associated with lower delay of gratification within impoverished children. Study 2 compared the relative role of vagal tone across two groups of children, one which experienced greater impoverishment and one which was relatively middle-class. Results indicated that within resource rich environments, high vagal tone was associated with greater delay of gratification. In contrast, high vagal tone in children living within resource poor environments was associated with reduced delay of gratification. The results are interpreted within evolutionary-developmental models of children’s stress response system functioning and adaptive behavior across varying contexts of economic risk. PMID:27117276
Noguchi, Kenshi; Shigemura, Noriatsu; Jyotaki, Masafumi; Takahashi, Ichiro; Margolskee, Robert F.
Leptin is known to selectively suppress neural and behavioral responses to sweet-tasting compounds. However, the molecular basis for the effect of leptin on sweet taste is not known. Here, we report that leptin suppresses sweet taste via leptin receptors (Ob-Rb) and KATP channels expressed selectively in sweet-sensitive taste cells. Ob-Rb was more often expressed in taste cells that expressed T1R3 (a sweet receptor component) than in those that expressed glutamate-aspartate transporter (a marker for Type I taste cells) or GAD67 (a marker for Type III taste cells). Systemically administered leptin suppressed taste cell responses to sweet but not to bitter or sour compounds. This effect was blocked by a leptin antagonist and was absent in leptin receptor–deficient db/db mice and mice with diet-induced obesity. Blocking the KATP channel subunit sulfonylurea receptor 1, which was frequently coexpressed with Ob-Rb in T1R3-expressing taste cells, eliminated the effect of leptin on sweet taste. In contrast, activating the KATP channel with diazoxide mimicked the sweet-suppressing effect of leptin. These results indicate that leptin acts via Ob-Rb and KATP channels that are present in T1R3-expressing taste cells to selectively suppress their responses to sweet compounds. PMID:26116698
Phat, Chanvorleak; Moon, BoKyung; Lee, Chan
Seventeen edible mushrooms commercially available in Korea were analysed for their umami taste compounds (5'-nucleotides: AMP, GMP, IMP, UMP, XMP; free amino acids: aspartic, glutamic acid) and subjected to human sensory evaluation and electronic tongue measurements. Amanita virgineoides featured the highest total 5'-nucleotide content (36.9 ± 1.50 mg/g), while monosodium glutamate-like components (42.4 ± 6.90 mg/g) were highest in Agaricus bisporus. The equivalent umami concentration (EUC) ranged from 1.51 ± 0.42 to 3890 ± 833 mg MSG/g dry weight; most mushrooms exhibited a high umami taste. Pleurotus ostreatus scored the highest in the human sensory evaluation, while Flammulina velutipes obtained the maximum score in the electronic tongue measurement. The EUC and the sensory score from the electronic tongue test were highly correlated, and also showed significant correlation with the human sensory evaluation score. These results suggest that the electronic tongue is suitable to determine the characteristic umami taste of mushrooms. Copyright © 2015 Elsevier Ltd. All rights reserved.
Margaret R Starostik
Full Text Available BACKGROUND: Multiple excitatory neurotransmitters have been identified in the mammalian taste transduction, with few studies focused on inhibitory neurotransmitters. Since the synthetic enzyme glutamate decarboxylase (GAD for gamma-aminobutyric acid (GABA is expressed in a subset of mouse taste cells, we hypothesized that other components of the GABA signaling pathway are likely expressed in this system. GABA signaling is initiated by the activation of either ionotropic receptors (GABA(A and GABA(C or metabotropic receptors (GABA(B while it is terminated by the re-uptake of GABA through transporters (GATs. METHODOLOGY/PRINCIPAL FINDINGS: Using reverse transcriptase-PCR (RT-PCR analysis, we investigated the expression of different GABA signaling molecules in the mouse taste system. Taste receptor cells (TRCs in the circumvallate papillae express multiple subunits of the GABA(A and GABA(B receptors as well as multiple GATs. Immunocytochemical analyses examined the distribution of the GABA machinery in the circumvallate papillae. Both GABA(A-and GABA(B- immunoreactivity were detected in the peripheral taste receptor cells. We also used transgenic mice that express green fluorescent protein (GFP in either the Type II taste cells, which can respond to bitter, sweet or umami taste stimuli, or in the Type III GAD67 expressing taste cells. Thus, we were able to identify that GABAergic receptors are expressed in some Type II and Type III taste cells. Mouse GAT4 labeling was concentrated in the cells surrounding the taste buds with a few positively labeled TRCs at the margins of the taste buds. CONCLUSIONS/SIGNIFICANCE: The presence of GABAergic receptors localized on Type II and Type III taste cells suggests that GABA is likely modulating evoked taste responses in the mouse taste bud.
Mann, Anna; Mol, Annemarie; Satalkar, Priya
hard to name. Pleasure and embarrassment, food-like vitality, erotic titillation, the satisfaction or discomfort that follow a meal-we suggest that these may all be included in "tasting." Thus teasing the language alters what speakers and eaters may sense and say. It complements the repertoires...... words to do so, we are compelled to stretch the verb "to taste." Tasting, or so our ethnographic experiment suggests, need not be understood as an activity confined to the tongue. Instead, if given a chance, it may viscously spread out to the fingers and come to include appreciative reactions otherwise...
Full Text Available There are many researches showing interactions between olfaction and taste. Many of them supported that the interactions are not innate, but are learned through our daily eating experiences. Stevenson (2009 called this phenomenon as “learned synesthesia”. The authors also showed the interactions between flavor and taste are learned and processed by higher cognitive systems in rats and humans (Sakai et al., 2001; Sakai and Imada, 2003. Here the interactions between umami taste and dashi flavors are developed by the daily eating experience of Japanese traditional cuisine. Twenty flavors (such as sea weed, bonito, onion, garlic, ginger etc. by courtesy of YAMAHO CO. Ltd. were used as flavor stimuli. Taste stimuli are monosodium glutamate (umami substance, MSG, miso soup, and Katsuo Dashi (bonito soup stock. Participants tasted these stimuli, 12∼20 stimuli in a day, and evaluated the strength of umami taste, the palatability, congruity between taste and flavor with 100 mm visual analogue scales. The results of evaluations analyzed with the participants' daily eating experience showed the interactions between taste and flavor are developed by their own daily intake of traditional Japanese cuisine, especially dashi soup.
Spector, Alan C.; Glendinning, John I
The act of eating and drinking brings food-related chemicals into contact with taste cells. Activation of these taste cells, in turn, engages neural circuits in the central nervous system that help animals identify foods and fluids, determine what and how much to eat, and prepare the body for digestion and assimilation. Analytically speaking, these neural processes can be divided into at least three categories: stimulus identification, ingestive motivation, and digestive preparation. This rev...
Taste buds are aggregates of 50–100 polarized neuroepithelial cells that detect nutrients and other compounds. Combined analyses of gene expression and cellular function reveal an elegant cellular organization within the taste bud. This review discusses the functional classes of taste cells, their cell biology, and current thinking on how taste information is transmitted to the brain. PMID:20696704
Castillo, David; Seidel, Kerstin; Salcedo, Ernesto; Ahn, Christina; de Sauvage, Frederic J.; Klein, Ophir D.; Barlow, Linda A.
Taste buds are assemblies of elongated epithelial cells, which are innervated by gustatory nerves that transmit taste information to the brain stem. Taste cells are continuously renewed throughout life via proliferation of epithelial progenitors, but the molecular regulation of this process remains unknown. During embryogenesis, sonic hedgehog (SHH) negatively regulates taste bud patterning, such that inhibition of SHH causes the formation of more and larger taste bud primordia, including in regions of the tongue normally devoid of taste buds. Here, using a Cre-lox system to drive constitutive expression of SHH, we identify the effects of SHH on the lingual epithelium of adult mice. We show that misexpression of SHH transforms lingual epithelial cell fate, such that daughter cells of lingual epithelial progenitors form cell type-replete, onion-shaped taste buds, rather than non-taste, pseudostratified epithelium. These SHH-induced ectopic taste buds are found in regions of the adult tongue previously thought incapable of generating taste organs. The ectopic buds are composed of all taste cell types, including support cells and detectors of sweet, bitter, umami, salt and sour, and recapitulate the molecular differentiation process of endogenous taste buds. In contrast to the well-established nerve dependence of endogenous taste buds, however, ectopic taste buds form independently of both gustatory and somatosensory innervation. As innervation is required for SHH expression by endogenous taste buds, our data suggest that SHH can replace the need for innervation to drive the entire program of taste bud differentiation. PMID:24993944
Wistoft, Karen; Qvortrup, Lars
“Taste for Life” (“Smag for Livet” in Danish) is a unique interdisciplinary research and communication center with focus on taste, food and the senses. The center involves researchers from the humanities (pedagogical and didactical scientists), natural sciences (sensory scientists...... and the humanities and social sciences. We do so by engaging scholars from different disciplines in a close, collaborative effort hereby generating new knowledge on taste. The center thus includes researchers from several universities and colleges, chefs from innovation kitchens, and teachers from elementary schools......, high schools and vocational educations. By integrating research, taste, learning, didactics and communication, our projects focus on three main areas: sensory sciences and didactics; gastrophysics and the integration of scientific disciplines; and innovation and honing of culinary skills. While we...
Yarmolinsky, David A.; Zuker, Charles S.; Ryba, Nicholas J.P.
The sense of taste is a specialized chemosensory system dedicated to the evaluation of food and drink. Despite the fact that vertebrates and insects have independently evolved distinct anatomic and molecular pathways for taste sensation, there are clear parallels in the organization and coding logic between the two systems. There is now persuasive evidence that tastant quality is mediated by labeled lines, whereby distinct and strictly segregated populations of taste receptor cells encode eac...
Ordelman, Simone C. M. A.; Kornet, Lilian; Cornelussen, Richard; Buschman, Hendrik P. J.; Veltink, Peter H.
The vagal nerve plays a vital role in the regulation of the cardiovascular system. It not only regulates the heart but also sends sensory information from the heart back to the brain. We hypothesize that the evoked vagal nerve compound action potential contains components that are indirect via the brain stem or coming via the neural network on the heart. In an experimental study of 15 pigs, we identified four components in the evoked compound action potentials. The fourth component was found to be an indirect component, which came from the periphery. The latency of the indirect component increased when heart rate and contractility were decreased by burst stimulation (P = 0.01; n = 7). When heart rate and contractility were increased by dobutamine administration, the latency of the indirect component decreased (P = 0.01; n = 9). This showed that the latency of the indirect component of the evoked compound action potentials may relate to the state of the cardiovascular system.
Rabinerson, David; Horovitz, Eran; Beloosesky, Yeshayahoo
The taste sense is one of the five human senses. It is essential to our survival because it enables the individual the choice of correct food, which, in turn, is crucial for one's existence, maintenance and function. This is a complicated chemical sense, which operates in conjunction with other senses such as vision, smell and touch, and is also associated with the operation of temperature and consistency receptors. There are five basic tastes: bitter, sweet, sour, salty and "fleshy" (umami), each of which has a role in food selection, being responsible for the recognition of certain chemicals, which may be either necessary or dangerous to our body. The taste cell is located in the taste buds, which, in turn, are situated in the tongue, oral cavity and the proximal third of the esophagus. This translates the chemical signal of tastants in food to electrical stimulation that transfers the signal to higher processing centers in the brain, in a process called transduction, which is explained in this review. Disturbances in the taste sense, as well as effects of industrial exposure on this sense are also described. The accumulated knowledge about the taste sense might enable future breakthroughs in the processed food industry.
Full Text Available Many commonly prescribed chemotherapy drugs such as cyclophosphamide (CYP have adverse side effects including disruptions in taste which can result in loss of appetite, malnutrition, poorer recovery and reduced quality of life. Previous studies in mice found evidence that CYP has a two-phase disturbance in taste behavior: a disturbance immediately following drug administration and a second which emerges several days later. In this study, we examined the processes by which CYP disturbs the taste system by examining the effects of the drug on taste buds and cells responsible for taste cell renewal using immunohistochemical assays. Data reported here suggest CYP has direct cytotoxic effects on lingual epithelium immediately following administration, causing an early loss of taste sensory cells. Types II and III cells in fungiform taste buds appear to be more susceptible to this effect than circumvallate cells. In addition, CYP disrupts the population of rapidly dividing cells in the basal layer of taste epithelium responsible for taste cell renewal, manifesting a disturbance days later. The loss of these cells temporarily retards the system's capacity to replace Type II and Type III taste sensory cells that survived the cytotoxic effects of CYP and died at the end of their natural lifespan. The timing of an immediate, direct loss of taste cells and a delayed, indirect loss without replacement of taste sensory cells are broadly congruent with previously published behavioral data reporting two periods of elevated detection thresholds for umami and sucrose stimuli. These findings suggest that chemotherapeutic disturbances in the peripheral mechanisms of the taste system may cause dietary challenges at a time when the cancer patient has significant need for well balanced, high energy nutritional intake.
Mukherjee, Nabanita; Pal Choudhuri, Shreoshi; Delay, Rona J; Delay, Eugene R
Many commonly prescribed chemotherapy drugs such as cyclophosphamide (CYP) have adverse side effects including disruptions in taste which can result in loss of appetite, malnutrition, poorer recovery and reduced quality of life. Previous studies in mice found evidence that CYP has a two-phase disturbance in taste behavior: a disturbance immediately following drug administration and a second which emerges several days later. In this study, we examined the processes by which CYP disturbs the taste system by examining the effects of the drug on taste buds and cells responsible for taste cell renewal using immunohistochemical assays. Data reported here suggest CYP has direct cytotoxic effects on lingual epithelium immediately following administration, causing an early loss of taste sensory cells. Types II and III cells in fungiform taste buds appear to be more susceptible to this effect than circumvallate cells. In addition, CYP disrupts the population of rapidly dividing cells in the basal layer of taste epithelium responsible for taste cell renewal, manifesting a disturbance days later. The loss of these cells temporarily retards the system's capacity to replace Type II and Type III taste sensory cells that survived the cytotoxic effects of CYP and died at the end of their natural lifespan. The timing of an immediate, direct loss of taste cells and a delayed, indirect loss without replacement of taste sensory cells are broadly congruent with previously published behavioral data reporting two periods of elevated detection thresholds for umami and sucrose stimuli. These findings suggest that chemotherapeutic disturbances in the peripheral mechanisms of the taste system may cause dietary challenges at a time when the cancer patient has significant need for well balanced, high energy nutritional intake.
Boudreau, James C.
At least 12 distinct taste sensations can be elicited from different parts of the oral cavity by distinct chemical compounds. The chemicals eliciting each sensation are often common constituents of foods, thus the umami sensations arise with stimulation by monosodium glutamate and nucleotides. These sensations can often be related to different physical/chemical stimulus parameters (e.g., bitterness and hydrophobicity) and neural activity in distinct chemosensory channels.
Anthi A Apostolopoulou
Full Text Available The Drosophila larva has a simple peripheral nervous system with a comparably small number of sensory neurons located externally at the head or internally along the pharynx to assess its chemical environment. It is assumed that larval taste coding occurs mainly via external organs (the dorsal, terminal and ventral organ. However, the contribution of the internal pharyngeal sensory organs has not been explored. Here we find that larvae require a single pharyngeal gustatory receptor neuron pair called D1, which is located in the dorsal pharyngeal sensilla, in order to avoid caffeine and to associate an odor with caffeine punishment. In contrast, caffeine-driven reduction in feeding in non-choice situations does not require D1. Hence, this work provides data on taste coding via different receptor neurons, depending on the behavioral context. Furthermore, we show that the larval pharyngeal system is involved in bitter tasting. Using ectopic expressions, we show that the caffeine receptor in neuron D1 requires the function of at least four receptor genes: the putative coreceptors Gr33a, Gr66a, the putative caffeine-specific receptor Gr93a, and yet unknown additional molecular component(s. This suggests that larval taste perception is more complex than previously assumed already at the sensory level. Taste information from different sensory organs located outside at the head or inside along the pharynx of the larva is assembled to trigger taste guided behaviours.
Nakamura, Yuko; Goto, Tazuko K; Tokumori, Kenji; Yoshiura, Takashi; Kobayashi, Koji; Nakamura, Yasuhiko; Honda, Hiroshi; Ninomiya, Yuzo; Yoshiura, Kazunori
There are no credible data to support the notion that individual taste qualities have dedicated pathways leading from the tongue to the end of the pathway in the brain. Moreover, the insular cortex is activated not only by taste but also by non-taste information from oral stimuli. These responses are invariably excitatory, and it is difficult to determine whether they are sensory, motor, or proprioceptive in origin. Furthermore, umami is a more unfamiliar and complex taste than other basic tastes. Considering these issues, it may be effective to minimize somatosensory stimuli, oral movement, and psychological effects in a neuroimaging study to elicit cerebral activity by pure umami on the human tongue. For this purpose, we developed an original taste delivery system for functional magnetic resonance imaging (fMRI) studies for umami. Then, we compared the results produced by two authorized models, namely, the block design model and event-related design model, to decide the appropriate model for detecting activation by umami. Activation by the umami taste was well localized in the insular cortex using our new system and block design model analysis. The peaks of the activated areas in the middle insular cortex by umami were very close to another prototypical taste quality (salty). Although we have to carefully interpret the perceiving intensities and brain activations by taste from different sessions, this study design might be effective for detecting the accession area in the cortex of pure umami taste on the tongue. Copyright © 2011 Elsevier B.V. All rights reserved.
More and more research studies are revealing unexpectedly important roles of taste for health and pathogenesis of various diseases. Only recently it has been shown that taste receptors have many extraoral locations (e.g., stomach, intestines, liver, pancreas, respiratory system, heart, brain, kidney, urinary bladder, pancreas, adipose tissue, testis, and ovary), being part of a large diffuse chemosensory system. The functional implications of these taste receptors widely dispersed in various organs or tissues shed a new light on several concepts used in ayurvedic pharmacology (dravyaguna vijnana), such as taste (rasa), postdigestive effect (vipaka), qualities (guna), and energetic nature (virya). This review summarizes the significance of extraoral taste receptors and transient receptor potential (TRP) channels for ayurvedic pharmacology, as well as the biological activities of various types of phytochemical tastants from an ayurvedic perspective. The relative importance of taste (rasa), postdigestive effect (vipaka), and energetic nature (virya) as ethnopharmacological descriptors within Ayurveda boundaries will also be discussed. PMID:28642799
Gagnon, Lea; Kupers, Ron; Ptito, Maurice
Sight is undoubtedly not only important for food identification and selection but also for the modulation of gustatory sensitivity. We can, therefore, assume that taste sensitivity and eating habits are affected by visual deprivation from birth. We measured taste detection and identification thresholds of the 5 basic tastants in 13 congenitally blind and 13 sighted control subjects. Participants also answered several eating habits questionnaires, including the Food Neophobia Scale, the Food Variety Seeking Tendency Scale, the Intuitive Eating Scale, and the Body Awareness Questionnaire. Our behavioral results showed that compared with the normal sighted, blind subjects have increased thresholds for taste detection and taste identification. This finding is at odds with the superior performance of congenitally blind subjects in several tactile, auditory and olfactory tasks. Our psychometric data further indicate that blind subjects more strongly rely on internal hunger and satiety cues, instead of external contextual or emotional cues, to decide when and what to eat. We suggest that the lower taste sensitivity observed in congenitally blind individuals is due to various blindness-related obstacles when shopping for food, cooking and eating out, all of which contribute to underexpose the gustatory system to a larger variety of taste stimuli.
Cedrick D Dotson
Full Text Available TAS1R- and TAS2R-type taste receptors are expressed in the gustatory system, where they detect sweet- and bitter-tasting stimuli, respectively. These receptors are also expressed in subsets of cells within the mammalian gastrointestinal tract, where they mediate nutrient assimilation and endocrine responses. For example, sweeteners stimulate taste receptors on the surface of gut enteroendocrine L cells to elicit an increase in intracellular Ca(2+ and secretion of the incretin hormone glucagon-like peptide-1 (GLP-1, an important modulator of insulin biosynthesis and secretion. Because of the importance of taste receptors in the regulation of food intake and the alimentary responses to chemostimuli, we hypothesized that differences in taste receptor efficacy may impact glucose homeostasis. To address this issue, we initiated a candidate gene study within the Amish Family Diabetes Study and assessed the association of taste receptor variants with indicators of glucose dysregulation, including a diagnosis of type 2 diabetes mellitus and high levels of blood glucose and insulin during an oral glucose tolerance test. We report that a TAS2R haplotype is associated with altered glucose and insulin homeostasis. We also found that one SNP within this haplotype disrupts normal responses of a single receptor, TAS2R9, to its cognate ligands ofloxacin, procainamide and pirenzapine. Together, these findings suggest that a functionally compromised TAS2R receptor negatively impacts glucose homeostasis, providing an important link between alimentary chemosensation and metabolic disease.
Lee, Robert J.
Taste receptors were first identified on the tongue, where they initiate a signaling pathway that communicates information to the brain about the nutrient content or potential toxicity of ingested foods. However, recent research has shown that taste receptors are also expressed in a myriad of other tissues, from the airway and gastrointestinal epithelia to the pancreas and brain. The functions of many of these extraoral taste receptors remain unknown, but emerging evidence suggests that bitter and sweet taste receptors in the airway are important sentinels of innate immunity. This review discusses taste receptor signaling, focusing on the G-protein coupled–receptors that detect bitter, sweet, and savory tastes, followed by an overview of extraoral taste receptors and in-depth discussion of studies demonstrating the roles of taste receptors in airway innate immunity. Future research on extraoral taste receptors has significant potential for identification of novel immune mechanisms and insights into host-pathogen interactions. PMID:25323130
Morrow, G R; Andrews, P L; Hickok, J T; Stern, R
Many physiological changes that occur contemporaneously with nausea are mediated by the autonomic nervous system, but the specific autonomic changes associated with nausea have not been characterized. Cardiac parasympathetic (vagal) activity as indicated by heart rate variability, measured as the standard deviation of successive differences (SDSD) in beat-to-beat intervals, was assessed in 24 women with ovarian cancer immediately prior to and accompanying nausea that occurred following anticancer chemotherapy. A progressive increase in SDSD followed infusion of the chemotherapy agent, indicating a rise in cardiac parasympathetic (vagal) activity, with onset of nausea consistently occurring after the peak activity had been reached, at a time when SDSD was decreasing. An increase in parasympathetic activity seems to set the stage for the expression of nausea but an additional stimulus is apparently needed to finally trigger the event.
Rash, Joshua A; Prkachin, Kenneth M
The induction of one particular emotion - sadness - has shown two different profiles of autonomic nervous system (ANS) response that are characterized by activation, or withdrawal in cardiac parasympathetic activation. We tested whether individual differences in emotion expression predict cardiac vagal reactivity from baseline to autobiographical sadness induction. Respiration sinus arrhythmia (RSA(c)) was measured in 56 adults (28 men) asked to relive an episode of sadness. Participants completed an emotional intelligence (EI) test, and a measure of trait affect intensity. Sadness resulted in cardiac vagal activation with concomitant increase in HR suggestive of parasympathetic and sympathetic co-activation. Individual differences were observed in autonomic reactivity during sadness. Higher scores on the affect intensity measure and the emotional intelligence test predicted greater change in RSA(c) during sadness and recovery. The tendency to experience affect intensely and the ability to perceive emotions predict adaptive physiological regulation during sadness. Copyright © 2012 Elsevier B.V. All rights reserved.
Bercik, P; Park, A J; Sinclair, D; Khoshdel, A; Lu, J; Huang, X; Deng, Y; Blennerhassett, P A; Fahnestock, M; Moine, D; Berger, B; Huizinga, J D; Kunze, W; McLean, P G; Bergonzelli, G E; Collins, S M; Verdu, E F
The probiotic Bifidobacterium longum NCC3001 normalizes anxiety-like behavior and hippocampal brain derived neurotrophic factor (BDNF) in mice with infectious colitis. Using a model of chemical colitis we test whether the anxiolytic effect of B. longum involves vagal integrity, and changes in neural cell function. Methods Mice received dextran sodium sulfate (DSS, 3%) in drinking water during three 1-week cycles. Bifidobacterium longum or placebo were gavaged daily during the last cycle. Some mice underwent subdiaphragmatic vagotomy. Behavior was assessed by step-down test, inflammation by myeloperoxidase (MPO) activity and histology. BDNF mRNA was measured in neuroblastoma SH-SY5Y cells after incubation with sera from B. longum- or placebo-treated mice. The effect of B. longum on myenteric neuron excitability was measured using intracellular microelectrodes. Chronic colitis was associated with anxiety-like behavior, which was absent in previously vagotomized mice. B. longum normalized behavior but had no effect on MPO activity or histological scores. Its anxiolytic effect was absent in mice with established anxiety that were vagotomized before the third DSS cycle. B. longum metabolites did not affect BDNF mRNA expression in SH-SY5Y cells but decreased excitability of enteric neurons. In this colitis model, anxiety-like behavior is vagally mediated. The anxiolytic effect of B. longum requires vagal integrity but does not involve gut immuno-modulation or production of BDNF by neuronal cells. As B. longum decreases excitability of enteric neurons, it may signal to the central nervous system by activating vagal pathways at the level of the enteric nervous system. © 2011 Blackwell Publishing Ltd.
Damholt, M B; Arlien-Soeborg, P; Hilsted, L
The diagnosis of autonomic neuropathy in diabetic patients is based on cardiovascular reflex tests. Since cardiac function may be affected by arteriosclerosis and cardiomyopathy in type 1 diabetes mellitus, alternative tests reflecting vagal nerve function, in other organ systems, are needed...
La Sala, Michael S.; Hurtado, Maria D.; Brown, Alicia R.; Bohórquez, Diego V.; Liddle, Rodger A.; Herzog, Herbert; Zolotukhin, Sergei; Dotson, Cedrick D.
It has been hypothesized that the peripheral taste system may be modulated in the context of an animal's metabolic state. One purported mechanism for this phenomenon is that circulating gastrointestinal peptides modulate the functioning of the peripheral gustatory system. Recent evidence suggests endocrine signaling in the oral cavity can influence food intake (FI) and satiety. We hypothesized that these hormones may be affecting FI by influencing taste perception. We used immunohistochemistry along with genetic knockout models and the specific reconstitution of peptide YY (PYY) in saliva using gene therapy protocols to identify a role for PYY signaling in taste. We show that PYY is expressed in subsets of taste cells in murine taste buds. We also show, using brief-access testing with PYY knockouts, that PYY signaling modulates responsiveness to bitter-tasting stimuli, as well as to lipid emulsions. We show that salivary PYY augmentation, via viral vector therapy, rescues behavioral responsiveness to a lipid emulsion but not to bitter stimuli and that this response is likely mediated via activation of Y2 receptors localized apically in taste cells. Our findings suggest distinct functions for PYY produced locally in taste cells vs. that circulating systemically.—La Sala, M. S., Hurtado, M. D., Brown, A. R., Bohórquez, D. V., Liddle, R. A., Herzog, H., Zolotukhin, S., Dotson, C. D. Modulation of taste responsiveness by the satiation hormone peptide YY. PMID:24043261
Garneau, Nicole L; Nuessle, Tiffany M; Tucker, Robin M; Yao, Mengjie; Santorico, Stephanie A; Mattes, Richard D
Dietary fats serve multiple essential roles in human health but may also contribute to acute and chronic health complications. Thus, understanding mechanisms that influence fat ingestion are critical. All sensory systems may contribute relevant cues to fat detection, with the most recent evidence supporting a role for the sense of taste. Taste detection thresholds for fat vary markedly between individuals and responses are not normally distributed. Genetics may contribute to these observations. Using crowdsourced data obtained from families visiting the Denver Museum of Nature & Science, our objective was to estimate the heritability of fat taste (oleogustus). A pedigree analysis was conducted with 106 families (643 individuals) who rated the fat taste intensity of graded concentrations of linoleic acid (LA) embedded in taste strips. The findings estimate that 19% (P = 0.043) of the variability of taste response to LA relative to baseline is heritable at the highest concentration tested. © The Author 2017. Published by Oxford University Press.
Leutzow, Bianca; Lange, Jörn; Gibb, Andreas; Schroeder, Henry; Nowak, Andreas; Wendt, Michael; Usichenko, Taras I
Transcutaneous vagal nerve stimulation is a promising treatment modality in patients suffering mood disorders and chronic pain, however, the mechanisms are still to be elucidated. A recently developed technique of EEG responses to electrical stimulation of the inner side of the tragus suggests that these responses are far field potentials, generated in the vagal system - Vagal Sensory Evoked Potentials (VSEP). To reproduce the VSEP technique free from myogenic artifacts. Fourteen ASA I-II patients scheduled for elective surgery in standardized Total Intravenous Anesthesia (TIVA) were enrolled. Transcutaneous electrical stimulation was applied to the inner side of the right tragus. Averaged EEG responses were recorded from the electrode positions C4-F4 and T4-O2 before and after induction of TIVA, during the maximal effect of the non-depolarizing muscle relaxing agent, cis-atracurium (C-AR) and after recovery from C-AR under TIVA. Typical response curves with P1, N1 and P2 peaks could be reproduced in all patients before and after anesthesia induction. The response curves disappeared during the C-AR action and re-appeared after recovery from C-AR under TIVA. The disappearance of the scalp responses to electrical tragus stimulation under the neuromuscular block suggests a muscular origin of these potentials. Copyright © 2013 Elsevier Inc. All rights reserved.
Full Text Available The number of implanted vagal nerve stimulators is growing and the need for removal or revision of the devices will become even more frequent. A significant concern about Vagus Nerve Stimulation (VNS therapy is the presence of the spiral stimulating electrodes, wrapped around the nerve, once treatment is considered ineffective or is no longer desired. Our purpose is to demonstrate the feasibility of complete removal and replacement of the vagal nerve stimulator electrodes using microsurgical technique even after a long period, without damaging the nerve. We attempted removal and replacement of spiral stimulating electrodes from a patient who received a 10-year long VNS therapy for drug-resistant epilepsy. Our results indicate that the spiral electrodes may be safely removed from the vagus nerve, even after several years. The reversibility of lead implantation may enhance the attractiveness of VNS therapy. Furthermore, with a correct microsurgical technique, it is possible to respect the normal anatomy and functionality of vagal nerve and to reimplant a new VNS system with all its components, maintaining the same therapeutic efficacy after many years.
Bachmanov, Alexander A.; Bosak, Natalia P; Floriano, Wely B.; INOUE, MASASHI; Li, Xia; Lin, Cailu; Murovets, Vladimir O.; Reed, Danielle R.; Zolotarev, Vasily A; Beauchamp, Gary K.
Sweet taste is a powerful factor influencing food acceptance. There is considerable variation in sweet taste perception and preferences within and among species. Although learning and homeostatic mechanisms contribute to this variation in sweet taste, much of it is genetically determined. Recent studies have shown that variation in the T1R genes contributes to within- and between-species differences in sweet taste. In addition, our ongoing studies using the mouse model demonstrate that a sign...
Peschel, Stephanie K V; Tylka, Tracy L; Williams, DeWayne P; Kaess, Michael; Thayer, Julian F; Koenig, Julian
Efferent and afferent fibers of the vagus nerve are involved in regulating hunger and satiety. Vagally-mediated heart rate variability (vmHRV) reflects vagal activity. Previously no study addressed a potential association between resting state vagal activity and intuitive eating. Self-reports on intuitive eating and measures of resting state vmHRV were obtained in 39 students (16 female, mean age: 19.64±1.44years). Hierarchical multiple regression models showed that, after controlling for gender, age, and body mass index, resting vagal activity was inversely related to the Unconditional Permission to Eat subscale of the Intuitive Eating scale. Individuals with higher resting vagal activity tend to be less willing to eat desired foods and are more likely to label certain foods as forbidden. Future studies should include measures of self-regulation and eating disorder symptomatology to identify potential mediators or moderators when attempting to replicate these preliminary findings in larger samples. Copyright © 2017 Elsevier B.V. All rights reserved.
Al-Omran, M F; Al-Suwayeh, S A; El-Helw, A M; Saleh, S I
This study addresses how to mask the undesirable taste of diclofenac sodium (DS) without interfering with an adequate rate of drug release. DS microcapsules were successfully prepared using a system of ethylcellulose (EC)-toluene-petroleum ether. The system was optimized by the construction of the phase diagram and determination of the amount of EC precipitated under different solvent:non-solvent ratios to determine the most appropriate conditions for preparing good microcapsules. Microcrystalline cellulose (Avicel) and lactose were mixed with DS powder and converted into spherical cores by the wet agglomeration technique which facilitated coacervation and formation of thin and uniform microcapsule walls. Diethylphthalate (DEP) and Polyethyleneglycol 600 (PEG) in different concentrations (20 or 40% w/w) were used as plasticizers to impart better elasticity to the microcapsules. The microcapsules were evaluated for DS released against crushed commercial DS enteric coated tablet (Voltaren). The prepared microcapsules were taste evaluated by a taste panel of 10 volunteers. The results revealed that the optimum solvent:non-solvent ratio required for microcapsule formation was 1:2. Microcapsules containing PEG 20% or DEP 40% showed a faster rate of DS release compared to that obtained from other microcapsules and crushed commercial enteric coated tablets (Voltaren). The palatability and the taste of DS were significantly improved by microencapsulation. The extent of taste masking was influenced by the microcapsule core:wall ratio, the presence of additives within the core, the type and concentration of plasticizer and initial core size.
Polder, G.; Young, T.; Schrauwers, A.
For over two decades, fruit and other agricultural products have been sorted using the 'electronic eye'. The eye selects purely by such external properties as colour, and cannot judge taste. Dr Gerrit Polder, an electrical engineer at Wageningen University, carried out his doctorate research at
Lee, Jung Seung; Cho, Ann-Na; Jin, Yoonhee; Kim, Jin; Kim, Suran; Cho, Seung-Woo
Artificial taste devices for tastant sensing and taste information standardization are attracting increasing attention with the exponential growth of the food and beverage industries. Despite recent developments in artificial taste sensors incorporating polymers, lipid membranes, and synthetic vesicles, current devices have limited functionality and sensitivity, and are complex to manufacture. Moreover, such synthetic systems cannot simulate the taste signal transmissions that are critical for complicated taste perception. The current document describes a primary taste cell-based artificial tongue that can mimic taste sensing. To maintain viable and functional taste cells required for in vitro tastant sensing, a tongue extracellular matrix (TEM) prepared by decellularization of tongue tissue was applied to two- and three-dimensional taste cell cultures. The TEM-based system recreates the tongue's microenvironment and significantly improves the functionality of taste cells for sensing tastant molecules by enhancing cellular adhesion and gustatory gene expression compared with conventional collagen-based systems. The TEM-based platform simulates signal transmission from tastant-treated taste cells to adjacent neuronal cells, which was impossible with previous artificial taste sensors. The artificial tongue device may provide highly efficient, functional sensors for tastant detection and in vitro organ models that mimic the tongue allowing elucidation of the mechanisms of taste. Copyright © 2017 Elsevier Ltd. All rights reserved.
Crowley, Olga V.; Kimhy, David; McKinley, Paula S.; Burg, Matthew M.; Schwartz, Joseph E.; Lachman, Margie E.; Tun, Patricia A.; Ryff, Carol D.; Seeman, Teresa E.; Sloan, Richard P.
Decline in executive functioning (EF) is a hallmark of cognitive aging. We have previously reported that faster vagal recovery from cognitive challenge is associated with better EF. This study examined the association between vagal recovery from cognitive challenge and age-related differences in EF among 817 participants in the Midlife in the U.S. study (aged 35–86). Cardiac vagal control was measured as high-frequency heart rate variability. Vagal recovery moderated the association between age and EF (β = .811, p = .004). Secondary analyses revealed that older participants (aged 65–86) with faster vagal recovery had superior EF compared to their peers who had slower vagal recovery. In contrast, among younger (aged 35–54) and middle-aged (aged 55–64) participants, vagal recovery was not associated with EF. We conclude that faster vagal recovery from cognitive challenge is associated with reduced deficits in EF among older, but not younger individuals. PMID:26303063
A multichannel taste sensor, namely an electronic tongue, with global selectivity is composed of several kinds of lipid/polymer membranes for transforming information about substances producing taste into electrical signals, which are input to a computer. The sensor output exhibits different patterns for chemical substances which have different taste qualities such as saltiness, sourness and bitterness, whereas it exhibits similar patterns for chemical substances with similar tastes. The sensor responds to the taste itself, as can be understood from the fact that taste interactions such as the suppression effect, which appears for mixtures of sweet and bitter substances, can be reproduced well. The suppression of the bitterness of quinine and a drug substance by sucrose can be quantified. Amino acids can be classified into several groups according to their own tastes on the basis of sensor outputs. The tastes of foodstuffs such as beer, coffee, mineral water, milk, sake, rice, soybean paste and vegetables can be discussed quantitatively using the taste sensor, which provides the objective scale for the human sensory expression. The flavour of a wine is also discriminated using the taste-odour sensory fusion conducted by combining the taste sensor and an odour-sensor array using conducting polymer elements. The taste sensor can also be applied to measurements of water pollution. Miniaturization of the taste sensor using FET produces the same characteristics as those of the above taste sensor by measuring the gate-source voltage. Use of the taste sensor will lead to a new era of food and environmental sciences.
Alexandre N Ermilov
suggest that taste alterations in cancer patients using systemic Hedgehog pathway inhibitors result principally from interruption of signaling activity in taste papillae.
Jones, P; Guillaud, L; Desbois, C; Benoist, J.F.; Combrisson, H; Dauger, S.; Peters, M J
The haemodynamic response to critical care intubation is influenced by the use of sedation and relaxant drugs and the activation of the vagal reflex. It has been hypothesized that different disease states may have a contrasting effect on the cardiovascular response to vagal stimulation. Our objective was to determine whether the blood pressure response to vagal stimulation was modified by endotoxaemia or hypovolaemia.
Voigt, Anja; Bojahr, Juliane; Narukawa, Masataka; Hübner, Sandra; Boehm, Ulrich; Meyerhof, Wolfgang
Taste perception begins in the oral cavity by interactions of taste stimuli with specific receptors. Specific subsets of taste receptor cells (TRCs) are activated upon tastant stimulation and transmit taste signals to afferent nerve fibers and ultimately to the brain. How specific TRCs impinge on the innervating nerves and how the activation of a subset of TRCs leads to the discrimination of tastants of different qualities and intensities is incompletely understood. To investigate the organization of taste circuits, we used gene targeting to express the transsynaptic tracer barley lectin (BL) in the gustatory system of mice. Because TRCs are not synaptically connected with the afferent nerve fibers, we first analyzed tracer production and transfer within the taste buds (TBs). Surprisingly, we found that BL is laterally transferred across all cell types in TBs of mice expressing the tracer under control of the endogenous Tas1r1 and Tas2r131 promotor, respectively. Furthermore, although we detected the BL tracer in both ganglia and brain, we also found local low-level Tas1r1 and Tas2r131 gene, and thus tracer expression in these tissues. Finally, we identified the Tas1r1 and Tas2r131-expressing cells in the peripheral and CNS using a binary genetic approach. Together, our data demonstrate that genetic transsynaptic tracing from bitter and umami receptor cells does not selectively label taste-specific neuronal circuits and reveal local taste receptor gene expression in the gustatory ganglia and the brain. Previous papers described the organization of taste pathways in mice expressing a transsynaptic tracer from transgenes in bitter or sweet/umami-sensing taste receptor cells. However, reported results differ dramatically regarding the numbers of synapses crossed and the reduction of signal intensity after each transfer step. Nevertheless, all groups claimed this approach appropriate for quality-specific visualization of taste pathways. In the present study, we
Gary K Beauchamp
There are two general approaches to reducing dietary sodium. First, there is considerable interest in developing salt substitutes and salt enhancers. Potassium chloride is widely used (usually in combination with NaCl as a substitute but it is not ideal since many find it has an unpleasant off-taste. There is considerable academic and industry research to identify new substitutes but to date there are none for salty as there are for sweet taste. A second approach to lowering sodium intake on a population-wide level in the United States, where more than 80% of the average person’s salt intake comes from food purchased and not from being added during cooking or at the table, is for food manufacturers and restaurants to gradually reduce the amount of salt in prepared foods. Experimental studies have demonstrated that if one reduces salt intake preferences for salt are similarly reduced. Based on this, the Institute of Medicine (IOM recommended that the Food and Drug Administration require gradual reduction by food manufacturers and large restaurant chains (IOM. The FDA has not acted on this recommendation. Conclusion. As illustrated by the difficulties in reducing salt in spite of the health benefits (a similar set of arguments for reducing excess consumption of carbohydrate sugars could be made, the sense of taste is a powerful driver of food intake. A deeper understanding of this important but neglected sensory system is required if we are to adequately address critical health problems in modern society that are often driven by excess consumption of tasty nutrients.
Mennella, Julie A.; Spector, Alan C.; Reed, Danielle R.; Coldwell, Susan E.
consume some medicines, they often are not effective in suppressing bitter tastes. Further development of psychophysical tools for children will help us better understand their sensory worlds. Multiple testing strategies will help us refine methods to assess acceptance and compliance/adherence by various pediatric populations. Research involving animal models, in which the gustatory system can be more invasively manipulated, can elucidate mechanisms, ultimately providing potential targets. These approaches, combined with new technologies and guided by findings from clinical studies, will potentially lead to effective ways to enhance drug acceptance and compliance in pediatric populations. PMID:23886820
Meng, Lingbin; Huang, Tao; Sun, Chengsan; Hill, David L; Krimm, Robin
Taste nerves readily regenerate to reinnervate denervated taste buds; however, factors required for regeneration have not yet been identified. When the chorda tympani nerve is sectioned, expression of brain-derived neurotrophic factor (BDNF) remains high in the geniculate ganglion and lingual epithelium, despite the loss of taste buds. These observations suggest that BDNF is present in the taste system after nerve section and may support taste nerve regeneration. To test this hypothesis, we inducibly deleted Bdnf during adulthood in mice. Shortly after Bdnf gene recombination, the chorda tympani nerve was unilaterally sectioned causing a loss of both taste buds and neurons, irrespective of BDNF levels. Eight weeks after nerve section, however, regeneration was differentially affected by Bdnf deletion. In control mice, there was regeneration of the chorda tympani nerve and taste buds reappeared with innervation. In contrast, few taste buds were reinnervated in mice lacking normal Bdnf expression such that taste bud number remained low. In all genotypes, taste buds that were reinnervated were normal-sized, but non-innervated taste buds remained small and atrophic. On the side of the tongue contralateral to the nerve section, taste buds for some genotypes became larger and all taste buds remained innervated. Our findings suggest that BDNF is required for nerve regeneration following gustatory nerve section. Copyright © 2017 Elsevier Inc. All rights reserved.
Noel, Alexis; Bhatia, Nitesh; Carter, Taren; Hu, David
Saliva plays a key role in digestion, speech and tactile sensation. Lack of saliva, also known as dry mouth syndrome, increases risk of tooth decay and alters sense of taste; nearly 10% of the general population suffer from this syndrome. In this experimental study, we investigate the spreading of water drops on wet and dry tongues of pigs and cows. We find that drops spread faster on a wet tongue than a dry tongue. We rationalize the spreading rate by consideration of the tongue microstructure, such as as papillae, in promoting wicking. By investigating how tongue microstructure affects spreading of fluids, we may begin to how understand taste receptors are activated by eating and drinking.
Yoshida, Ryusuke; Noguchi, Kenshi; Shigemura, Noriatsu; Jyotaki, Masafumi; Takahashi, Ichiro; Margolskee, Robert F; Ninomiya, Yuzo
Leptin is known to selectively suppress neural and behavioral responses to sweet-tasting compounds. However, the molecular basis for the effect of leptin on sweet taste is not known. Here, we report that leptin suppresses sweet taste via leptin receptors (Ob-Rb) and KATP channels expressed selectively in sweet-sensitive taste cells. Ob-Rb was more often expressed in taste cells that expressed T1R3 (a sweet receptor component) than in those that expressed glutamate-aspartate transporter (a marker for Type I taste cells) or GAD67 (a marker for Type III taste cells). Systemically administered leptin suppressed taste cell responses to sweet but not to bitter or sour compounds. This effect was blocked by a leptin antagonist and was absent in leptin receptor-deficient db/db mice and mice with diet-induced obesity. Blocking the KATP channel subunit sulfonylurea receptor 1, which was frequently coexpressed with Ob-Rb in T1R3-expressing taste cells, eliminated the effect of leptin on sweet taste. In contrast, activating the KATP channel with diazoxide mimicked the sweet-suppressing effect of leptin. These results indicate that leptin acts via Ob-Rb and KATP channels that are present in T1R3-expressing taste cells to selectively suppress their responses to sweet compounds. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.
McCaughey, Stuart A.
Sugars evoke a distinctive perceptual quality (“sweetness” in humans) and are generally highly preferred. The neural basis for these phenomena is reviewed for rodents, in which detailed electrophysiological measurements have been made. A receptor has been identified that binds sweeteners and activates G-protein-mediated signaling in taste receptor cells, which leads to changes in neural firing rates in the brain, where perceptions of taste quality, intensity, and palatability are generated. Most cells in gustatory nuclei are broadly-tuned, so quality perception presumably arises from patterns of activity across neural populations. However, some manipulations affect only the most sugar-oriented cells, making it useful to consider them as a distinct neural subtype. Quality perception may also arise partly due to temporal patterns of activity to sugars, especially within sugar-oriented cells that give large but delayed responses. Non-specific gustatory neurons that are excited by both sugars and unpalatable stimuli project to ventral forebrain areas, where neural responses provide a closer match with behavioral preferences. This transition likely involves opposing excitatory and inhibitory influences by different subgroups of gustatory cells. Sweeteners are generally preferred over water, but the strength of this preference can vary across time or between individuals, and higher preferences for sugars are often associated with larger taste-evoked responses. PMID:18499254
Vagal schwannomas are benign, rare peripheral nerve sheath tumors in the head and neck region. Some physicians opt to closely observe cases of schwannoma of the neck on an outpatient basis rather than to perform radical surgery. However, there is a possibility, albeit rare, of malignant transformation of a.
Effect of electrical vagal stimulation and bilateral vagotomy on the flow and electrolyte composition of bile was studied in fasted and anaesthetized male albino Wistar Rats. Entero-hepatic circulation was maintained artificially by continuous infusion of 1% sodium teurocholate. In each experiment, bile was collected at 15 ...
Lind, P; Hintze, U; Møller, M
OBJECTIVE: The purpose of this study was to evaluate the effects of thrombolytic therapy on vagal tone after acute myocardial infarction (AMI). DESIGN: Holter monitoring for 24 h was performed at hospital discharge and 6 weeks after AMI in 74 consecutive male survivors of a first AMI, who fulfilled...
Here, we are reporting the first case from the Indian subcontinent which was transformed into the angiosarcoma from benign vagal schwannoma over a long period. A 47‑year‑old male patient complaining of left sided neck swelling since last 12 years, swelling was insidious in onset, gradually progressive very slowly. In last ...
Menizibeya O. Welcome
Full Text Available Sweet taste receptors are transmembrane protein network specialized in the transmission of information from special “sweet” molecules into the intracellular domain. These receptors can sense the taste of a range of molecules and transmit the information downstream to several acceptors, modulate cell specific functions and metabolism, and mediate cell-to-cell coupling through paracrine mechanism. Recent reports indicate that sweet taste receptors are widely distributed in the body and serves specific function relative to their localization. Due to their pleiotropic signaling properties and multisubstrate ligand affinity, sweet taste receptors are able to cooperatively bind multiple substances and mediate signaling by other receptors. Based on increasing evidence about the role of these receptors in the initiation and control of absorption and metabolism, and the pivotal role of metabolic (glucose regulation in the central nervous system functioning, we propose a possible implication of sweet taste receptor signaling in modulating cognitive functioning.
Welcome, Menizibeya O.; Mastorakis, Nikos E.; Pereverzev, Vladimir A.
Sweet taste receptors are transmembrane protein network specialized in the transmission of information from special “sweet” molecules into the intracellular domain. These receptors can sense the taste of a range of molecules and transmit the information downstream to several acceptors, modulate cell specific functions and metabolism, and mediate cell-to-cell coupling through paracrine mechanism. Recent reports indicate that sweet taste receptors are widely distributed in the body and serves specific function relative to their localization. Due to their pleiotropic signaling properties and multisubstrate ligand affinity, sweet taste receptors are able to cooperatively bind multiple substances and mediate signaling by other receptors. Based on increasing evidence about the role of these receptors in the initiation and control of absorption and metabolism, and the pivotal role of metabolic (glucose) regulation in the central nervous system functioning, we propose a possible implication of sweet taste receptor signaling in modulating cognitive functioning. PMID:25653876
Stenbak Larsen, Christian
that the pupils were encouraged to use their senses: listen to things frying, touch the meat to check if it was done and taste the food in the process of seasoning it. But while some children learned what the teachers expected: to produce well tasting food, others learned to cook very salty and hot food...... appreciated by the group of boys, and others again learned to stick with their idiosyncrasies when pressured by the teacher. Conclusions: Children were acquiring taste in the home economic lessons, but not only the kind of tastes that the teacher had planned for. This leads to reflections on the very complex...... process of taste acquiring and to a call for further research into taste acquiring in complex real life contexts as home economics lessons....
TRP channels are expressed in taste buds, nerve fibers, and keratinocytes in the oronasal cavity. These channels play integral roles in transducing chemical stimuli, giving rise to sensations of taste, irritation, warmth, coolness, and pungency. Specifically, TRPM5 acts downstream of taste receptors in the taste transduction pathway. TRPM5 channels convert taste-evoked intracellular Ca2+ release into membrane depolarization to trigger taste transmitter secretion. PKD2L1 is expressed in acid-sensitive (sour) taste bud cells but is unlikely to be the transducer for sour taste. TRPV1 is a receptor for pungent chemical stimuli such as capsaicin and for several irritants (chemesthesis). It is controversial whether TRPV1 is present in the taste buds and plays a direct role in taste. Instead, TRPV1 is expressed in non-gustatory sensory afferent fibers and in keratinocytes of the oronasal cavity. In many sensory fibers and epithelial cells lining the oronasal cavity, TRPA1 is also co-expressed with TRPV1. As with TRPV1, TRPA1 transduces a wide variety of irritants and, in combination with TRPV1, assures that there is a broad response to noxious chemical stimuli. Other TRP channels, including TRPM8, TRPV3, and TRPV4, play less prominent roles in chemesthesis and no known role in taste, per se. The pungency of foods and beverages is likely highly influenced by the temperature at which they are consumed, their acidity, and, for beverages, their carbonation. All these factors modulate the activity of TRP channels in taste buds and in the oronasal mucosa. PMID:24961971
Paul Nathan Goldwater
Full Text Available Recent findings suggest that infection (and sepsis stand alone as the only plausible mechanism of causation of sudden infant death syndrome (SIDS and accordingly achieves congruence with all clinicopathological and epidemiological findings. This review examines the role of infection in the pathogenesis of SIDS in the context of the major risk factor of prone sleep position. The study explores how sleep position could interact with the immune system and inflammatory response via vagal neural connections, which could play key roles in gut and immune homeostasis. A plausible and congruent clinicopathological and epidemiological paradigm is suggested.
Goldwater, Paul Nathan
Recent findings suggest that infection (and sepsis) stand alone as the only plausible mechanism of causation of sudden infant death syndrome (SIDS) and accordingly achieves congruence with all clinicopathological and epidemiological findings. This review examines the role of infection in the pathogenesis of SIDS in the context of the major risk factor of prone sleep position. The study explores how sleep position could interact with the immune system and inflammatory response via vagal neural connections, which could play key roles in gut and immune homeostasis. A plausible and congruent clinicopathological and epidemiological paradigm is suggested.
Noriatsu Shigemura, DDS, PhD
Full Text Available The sense of taste plays a major role in evaluating the quality of food components in the oral cavity. Sweet, salty, umami, sour and bitter taste are generally accepted as five basic taste qualities. Among them, salty taste is attractive to animals and influences sodium intake. Angiotensin II (ANG II and aldosterone (ALDO, which is stimulated by ANG II are key hormones that regulate sodium homeostasis and water balance. At the peripheral gustatory organs, it has been reported that ALDO increases the amiloride-sensitivity of the rat gustatory neural responses to NaCl in a time course of several hours. A recent study demonstrated that ANG II suppresses amiloride-sensitivity of the mouse gustatory and behavioral responses to NaCl via its receptor AT1 within an hour. Moreover, ANG II enhances sweet taste sensitivity without affecting umami, sour and bitter tastes. These results suggest that the reciprocal and sequential regulatory mechanisms by ANG II (as an acute suppressor together with ALDO (as a slow enhancer on the salt taste sensitivity may exist in peripheral taste organs, contribute to salt intake, and play an important role in sodium homeostasis. Furthermore, the linkage between salty and sweet taste modulations via the ANG II signaling may optimize sodium and calorie intakes.
Medler, Kathryn F
The sense of taste is a common ability shared by all organisms and is used to detect nutrients as well as potentially harmful compounds. Thus taste is critical to survival. Despite its importance, surprisingly little is known about the mechanisms generating and regulating responses to taste stimuli. All taste responses depend on calcium signals to generate appropriate responses which are relayed to the brain. Some taste cells have conventional synapses and rely on calcium influx through voltage-gated calcium channels. Other taste cells lack these synapses and depend on calcium release to formulate an output signal through a hemichannel. Beyond establishing these characteristics, few studies have focused on understanding how these calcium signals are formed. We identified multiple calcium clearance mechanisms that regulate calcium levels in taste cells as well as a calcium influx that contributes to maintaining appropriate calcium homeostasis in these cells. Multiple factors regulate the evoked taste signals with varying roles in different cell populations. Clearly, calcium signaling is a dynamic process in taste cells and is more complex than has previously been appreciated. This article is part of a Special Issue entitled: 13th European Symposium on Calcium. Copyright © 2014 Elsevier B.V. All rights reserved.
Anselmi, L; Toti, L; Bove, C; Travagli, R A
Dopamine (DA)-containing fibers and neurons are embedded within the brain stem dorsal vagal complex (DVC); we have shown previously that DA modulates the membrane properties of neurons of the dorsal motor nucleus of the vagus (DMV) via DA1 and DA2 receptors. The vagally dependent modulation of gastric tone and phasic contractions, i.e., motility, by DA, however, has not been characterized. With the use of microinjections of DA in the DVC while recording gastric tone and motility, the aims of the present study were 1) assess the gastric effects of brain stem DA application, 2) identify the DA receptor subtype, and, 3) identify the postganglionic pathway(s) activated. Dopamine microinjection in the DVC decreased gastric tone and motility in both corpus and antrum in 29 of 34 rats, and the effects were abolished by ipsilateral vagotomy and fourth ventricular treatment with the selective DA2 receptor antagonist L741,626 but not by application of the selective DA1 receptor antagonist SCH 23390. Systemic administration of the cholinergic antagonist atropine attenuated the inhibition of corpus and antrum tone in response to DA microinjection in the DVC. Conversely, systemic administration of the nitric oxide synthase inhibitor nitro-l-arginine methyl ester did not alter the DA-induced decrease in gastric tone and motility. Our data provide evidence of a dopaminergic modulation of a brain stem vagal neurocircuit that controls gastric tone and motility.NEW & NOTEWORTHY Dopamine administration in the brain stem decreases gastric tone and phasic contractions. The gastric effects of dopamine are mediated via dopamine 2 receptors on neurons of the dorsal motor nucleus of the vagus. The inhibitory effects of dopamine are mediated via inhibition of the postganglionic cholinergic pathway. Copyright © 2017 the American Physiological Society.
Full Text Available BACKGROUND: The gustatory system plays a critical role in determining food preferences, food intake and energy balance. The exact mechanisms that fine tune taste sensitivity are currently poorly defined, but it is clear that numerous factors such as efferent input and specific signal transduction cascades are involved. METHODOLOGY/PRINCIPAL FINDINGS: Using immunohistochemical analyses, we show that ghrelin, a hormone classically considered to be an appetite-regulating hormone, is present within the taste buds of the tongue. Prepro-ghrelin, prohormone convertase 1/3 (PC 1/3, ghrelin, its cognate receptor (GHSR, and ghrelin-O-acyltransferase (GOAT , the enzyme that activates ghrelin are expressed in Type I, II, III and IV taste cells of mouse taste buds. In addition, ghrelin and GHSR co-localize in the same taste cells, suggesting that ghrelin works in an autocrine manner in taste cells. To determine a role for ghrelin in modifying taste perception, we performed taste behavioral tests using GHSR null mice. GHSR null mice exhibited significantly reduced taste responsivity to sour (citric acid and salty (sodium chloride tastants. CONCLUSIONS/SIGNIFICANCE: These findings suggest that ghrelin plays a local modulatory role in determining taste bud signaling and function and could be a novel mechanism for the modulation of salty and sour taste responsivity.
Shin, Yu-Kyong; Martin, Bronwen; Kim, Wook; White, Caitlin M; Ji, Sunggoan; Sun, Yuxiang; Smith, Roy G; Sévigny, Jean; Tschöp, Matthias H; Maudsley, Stuart; Egan, Josephine M
The gustatory system plays a critical role in determining food preferences, food intake and energy balance. The exact mechanisms that fine tune taste sensitivity are currently poorly defined, but it is clear that numerous factors such as efferent input and specific signal transduction cascades are involved. Using immunohistochemical analyses, we show that ghrelin, a hormone classically considered to be an appetite-regulating hormone, is present within the taste buds of the tongue. Prepro-ghrelin, prohormone convertase 1/3 (PC 1/3), ghrelin, its cognate receptor (GHSR), and ghrelin-O-acyltransferase (GOAT , the enzyme that activates ghrelin) are expressed in Type I, II, III and IV taste cells of mouse taste buds. In addition, ghrelin and GHSR co-localize in the same taste cells, suggesting that ghrelin works in an autocrine manner in taste cells. To determine a role for ghrelin in modifying taste perception, we performed taste behavioral tests using GHSR null mice. GHSR null mice exhibited significantly reduced taste responsivity to sour (citric acid) and salty (sodium chloride) tastants. These findings suggest that ghrelin plays a local modulatory role in determining taste bud signaling and function and could be a novel mechanism for the modulation of salty and sour taste responsivity.
Onoda, Keiko; Ikeda, Minoru; Sekine, Hiroki; Ogawa, Hisashi
The aim of this work is to examine the clinical findings of patients with taste disorders due to central lesions and also to study the central gustatory pathway in humans. We conducted a retrospective review of 13 patients with central taste disorders that visited Nihon University Itabashi Hospital. An additional 25 cases with central taste disorders previously reported in the literature were assessed in the study. We examined 38 patients with taste disorders due to central lesions. The sites of the central lesions and their frequencies, the laterality of taste disorders relative to the central lesions, and prognosis of taste disorders were studied. We identified the following taste-related regions in the central nervous system: the medulla, pons, midbrain, thalamus, internal capsule, putamen, corona radiata, and cerebral cortex. As for the laterality of the taste disorders, we observed more ipsilateral cases for lesions located from the medulla to the pons. We observed ipsilateral, contralateral, and bilateral cases for lesions located above the midbrain, but bilateral cases were more frequently detected. Taste disorders of 80% of the patients improved by 24 weeks. The prognoses of central taste disorders appeared to be good. We identified eight central regions supposed to be relate to taste disorders. From the laterality of the taste disorders relative to the central lesions, it was suggested that the central gustatory pathway ascends ipsilaterally from the medulla to the pons, branches at the upper pons, and then ascends bilaterally from the midbrain to the cerebral cortex.
McCabe, Ciara; Rolls, Edmund T
Umami taste is produced by glutamate acting on a fifth taste system. However, glutamate presented alone as a taste stimulus is not highly pleasant, and does not act synergistically with other tastes (sweet, salt, bitter and sour). We show here that when glutamate is given in combination with a consonant, savory, odour (vegetable), the resulting flavor can be much more pleasant. Moreover, we showed using functional brain imaging with fMRI that the glutamate taste and savory odour combination produced much greater activation of the medial orbitofrontal cortex and pregenual cingulate cortex than the sum of the activations by the taste and olfactory components presented separately. Supralinear effects were much less (and significantly less) evident for sodium chloride and vegetable odour. Further, activations in these brain regions were correlated with the pleasantness and fullness of the flavor, and with the consonance of the taste and olfactory components. Supralinear effects of glutamate taste and savory odour were not found in the insular primary taste cortex. We thus propose that glutamate acts by the nonlinear effects it can produce when combined with a consonant odour in multimodal cortical taste-olfactory convergence regions. We propose the concept that umami can be thought of as a rich and delicious flavor that is produced by a combination of glutamate taste and a consonant savory odour. Glutamate is thus a flavor enhancer because of the way that it can combine supralinearly with consonant odours in cortical areas where the taste and olfactory pathways converge far beyond the receptors.
Jung, Hyo Young; Kim, Woosuk; Yoo, Dae Young; Nam, Sung Min; Kim, Jong Whi; Choi, Jung Hoon; Yoon, Yeo Sung; Kim, Hye Young; Hwang, In Koo
Natural toxic substances have a bitter taste and their ingestion sends signals to the brain leading to aversive oral sensations. In the present study, we investigated chronological changes in c-Fos immunoreactivity in the nucleus tractus solitarius (NTS) to study the bitter taste reaction time of neurons in the NTS. Equal volumes (0.5 mL) of denatonium benzoate (DB), a bitter tastant, or its vehicle (distilled water) were administered to rats intragastrically. The rats were sacrificed at 0, 0.5, 1, 2, 4, 8, or 16 h after treatment. In the vehicle-treated group, the number of c-Fos-positive nuclei started to increase 0.5 h after treatment and peaked 2 h after gavage. In contrast, the number of c-Fos-positive nuclei in the DB-treated group significantly increased 1 h after gavage. Thereafter, the number of c-Fos immunoreactive nuclei decreased over time. The number of c-Fos immunoreactive nuclei in the NTS was also increased in a dose-dependent manner 1 h after gavage. Subdiaphragmatic vagotomy significantly decreased DB-induced neuronal activation in the NTS. These results suggest that intragastric DB increases neuronal c-Fos expression in the NTS 1 h after gavage and this effect is mediated by vagal afferent fibers.
Full Text Available The effect of swimming training (ST on vagal and sympathetic cardiac effects was investigated in sedentary (S, N = 12 and trained (T, N = 12 male Wistar rats (200-220 g. ST consisted of 60-min swimming sessions 5 days/week for 8 weeks, with a 5% body weight load attached to the tail. The effect of the autonomic nervous system in generating training-induced resting bradycardia (RB was examined indirectly after cardiac muscarinic and adrenergic receptor blockade. Cardiac hypertrophy was evaluated by cardiac weight and myocyte morphometry. Plasma catecholamine concentrations and citrate synthase activity in soleus muscle were also determined in both groups. Resting heart rate was significantly reduced in T rats (355 ± 16 vs 330 ± 20 bpm. RB was associated with a significantly increased cardiac vagal effect in T rats (103 ± 25 vs 158 ± 40 bpm, since the sympathetic cardiac effect and intrinsic heart rate were similar for the two groups. Likewise, no significant difference was observed for plasma catecholamine concentrations between S and T rats. In T rats, left ventricle weight (13% and myocyte dimension (21% were significantly increased, suggesting cardiac hypertrophy. Skeletal muscle citrate synthase activity was significantly increased by 52% in T rats, indicating endurance conditioning. These data suggest that RB induced by ST is mainly mediated parasympathetically and differs from other training modes, like running, that seems to mainly decrease intrinsic heart rate in rats. The increased cardiac vagal activity associated with ST is of clinical relevance, since both are related to increased life expectancy and prevention of cardiac events.
Full Text Available BACKGROUND: Alterations in muscarinic receptor expression and acetylcholinesterase (AchE activity have been observed in tissues from Sudden Infant Death Syndrome (SIDS. Vagal overactivity has been proposed as a possible cause of SIDS as well as of vasovagal syncopes. The aim of the present study was to seek whether muscarinic receptor overexpression may be the underlying mechanism of vagal hyperreactivity. Rabbits with marked vagal pauses following injection of phenylephrine were selected and crossed to obtain a vagal hyperreactive strain. The density of cardiac muscarinic receptors and acetylcholinesterase (AchE gene expression were assessed. Blood markers of the observed cardiac abnormalities were also sought. METHODOLOGY/PRINCIPAL FINDINGS: Cardiac muscarinic M(2 and M(3 receptors were overexpressed in hyperreactive rabbits compared to control animals (2.3-fold and 2.5-fold, respectively and the severity of the phenylephrine-induced bradycardia was correlated with their densities. A similar overexpression of M(2 receptors was observed in peripheral mononuclear white blood cells, suggesting that cardiac M(2 receptor expression can be inferred with high confidence from measurements in blood cells. Sequencing of the coding fragment of the M(2 receptor gene revealed a single nucleotide mutation in 83% of hyperreactive animals, possibly contributing for the transcript overexpression. Significant increases in AchE expression and activity were also assessed (AchE mRNA amplification ratio of 3.6 versus normal rabbits. This phenomenon might represent a compensatory consequence of muscarinic receptors overexpression. Alterations in M(2 receptor and AchE expression occurred between the 5th and the 7th week of age, a critical period also characterized by a higher mortality rate of hyperreactive rabbits (52% in H rabbits versus 13% in normal rabbits and preceeded the appearance of functional disorders. CONCLUSIONS/SIGNIFICANCE: The results suggest that
Zhou, Xinyan; Zhang, Kejia; Zhang, Tuqiao; Li, Cong; Mao, Xinwei
It is important for water utilities to provide esthetically acceptable drinking water to the public, because our consumers always initially judge the quality of the tap water by its color, taste, and odor (T&O). Microorganisms in drinking water contribute largely to T&O production and drinking water distribution systems (DWDS) are known to harbor biofilms and microorganisms in bulk water, even in the presence of a disinfectant. These microbes include T&O-causing bacteria, fungi, and algae, which may lead to unwanted effects on the organoleptic quality of distributed water. Importantly, the understanding of types of these microbes and their T&O compound-producing mechanisms is needed to prevent T&O formation during drinking water distribution. Additionally, new disinfection strategies and operation methods of DWDS are also needed for better control of T&O problems in drinking water. This review covers: (1) the microbial species which can produce T&O compounds in DWDS; (2) typical T&O compounds in DWDS and their formation mechanisms by microorganisms; (3) several common factors in DWDS which can influence the growth and T&O generation of microbes; and (4) several strategies to control biofilm and T&O compound formation in DWDS. At the end of this review, recommendations were given based on the conclusion of this review.
Kawabata, Yuko; Kawabata, Fuminori; Nishimura, Shotaro; Tabata, Shoji
It has been reported that a functional fat-taste receptor, GPR120, is present in chicken oral tissues, and that chickens can detect fat taste in a behavioral test. However, although triglycerides need to be digested to free fatty acids to be recognized by fat-taste receptors such as GPR120, it remains unknown whether lipase activities exist in chicken oral tissues. To examine this question, we first cloned another fat-taste receptor candidate gene, CD36, from the chicken palate. Then, using RT-PCR, we determined that GPR120 and CD36 were broadly expressed in chicken oral and gastrointestinal tissues. Also by RT-PCR, we confirmed that several lipase genes were expressed in both oral and gastrointestinal tissues. Finally, we analyzed the lipase activities of oral tissues by using a fluorogenic triglyceride analog as a lipase substrate. We found there are functional lipases in oral tissues as well as in the stomach and pancreas. These results suggested that chickens have a basic fat-taste reception system that incorporates a triglycerides/oral-lipases/free fatty acids/GPR120 axis and CD36 axis. Copyright © 2017 Elsevier Inc. All rights reserved.
King, Tanya J.; Donaldson, Jilleen A.; Harry, Emma
This paper describes a field trip by senior undergraduate anthropology students to a local winery, where they participated in a wine-tasting class with winery staff. In response to explicit hints from a wine-tasting facilitator, and more subtle cues from the cultural capital embedded in their surroundings and the winery staff, the students…
Roura, Eugeni; Foster, Simon; Winklebach, Anja
The association between salty taste and NaCl intake with hypertension is well-established, although it is far from completely understood. Other taste types such as sweet, umami or bitter have also been related to alterations in blood pressure. Here, we review the mutual relationship between taste...... and hypertension to identify potential avenues to better control blood pressure. This review focuses on published data involving humans, with the exception of a section on molecular mechanisms. There is compelling evidence to suggest that changes in salty taste sensitivity can be used to predict the onset...... of hypertension. This goes hand in hand with the medical concept of sodium sensitivity, which also increases with age, particularly in hypertensive patients. The association of hypertension with the loss of taste acuity less definitive with some data/conclusions masked by the use of anti-hypertensive drugs...
Recent ethnographies from the anthropology of food and the senses have shown how moments in which people taste foods are shaped by scientific knowledge, methods and rationales. Building on approaches developed in science and technology studies, this paper offers an ethnography of the field to which...... this shaping power has been assigned: the scientific study of taste. Detailed tracing and analysis of two laboratory experiments on taste performed in laboratories in Western Europe brings out how both turn moments in which people taste into a bodily response. At the same time, since their technical set......-ups address different societal problems and varying interest groups, they stage diverging versions: a perception versus a reaction to an exposure. The paper, thus, sheds light on how cultural and social norms, ideals, and practices shape the knowledge production about taste and its resulting effects....
l-Glutamate elicits the umami taste sensation, now recognized as a fifth distinct taste quality. A characteristic feature of umami taste is its potentiation by 5′-ribonucleotides such as guanosine-5'-monophosphate and inosine 5′-monophosphate, which also elicit the umami taste on their own. Recent data suggest that multiple G protein–coupled receptors contribute to umami taste. This review will focus on events downstream of the umami taste receptors. Ligand binding leads to Gβγ activation of phospholipase C β2, which produces the second messengers inositol trisphosphate and diacylglycerol. Inositol trisphosphate binds to the type III inositol trisphosphate receptor, which causes the release of Ca2+ from intracellular stores and Ca2+-dependent activation of a monovalent-selective cation channel, TRPM5. TRPM5 is believed to depolarize taste cells, which leads to the release of ATP, which activates ionotropic purinergic receptors on gustatory afferent nerve fibers. This model is supported by knockout of the relevant signaling effectors as well as physiologic studies of isolated taste cells. Concomitant with the molecular studies, physiologic studies show that l-glutamate elicits increases in intracellular Ca2+ in isolated taste cells and that the source of the Ca2+ is release from intracellular stores. Both Gα gustducin and Gα transducin are involved in umami signaling, because the knockout of either subunit compromises responses to umami stimuli. Both α-gustducin and α-transducin activate phosphodiesterases to decrease intracellular cAMP. The target of cAMP in umami transduction is not known, but membrane-permeant analogs of cAMP antagonize electrophysiologic responses to umami stimuli in isolated taste cells, which suggests that cAMP may have a modulatory role in umami signaling. PMID:19571214
Paiva, Vagner Clayton de; Santana, Kelen Rabelo; Silva, Bruno Moreira; Ramos, Plínio Santos; Lovisi, Júlio César Moraes; Araújo, Claudio Gil Soares de; Ricardo, Djalma Rabelo
Several methods have been used to assess cardiac vagal modulation, but there are gaps regarding the association and accuracy of these methods. To investigate the association between three valid, reproducible and commonly methods used to assess cardiac vagal modulation and compare their accuracies. Thirty healthy men (23 ± 4 years) and 15 men with coronary artery disease (61 ± 10 years) were evaluated in counterbalanced design by Heart Rate Variability (HRV; variables: the time domain = pNN50, SDNN and RMSSD, the frequency domain HF = ms² and HF n.u.), Respiratory Sinus Arrhythmia (RSA) and 4-second Exercise Test (T4s). Thirty healthy men (23 ± 4 years) and 15 men with coronary artery disease (61 ± 10 years) were evaluated in counterbalanced order by Heart Rate Variability (HRV; variables: the time domain = pNN50, SDNN and RMSSD, the frequency domain HF = ms² and HF n.u.), Respiratory Sinus Arrhythmia (RSA) and 4-second Exercise Test (T4s). Healthy subjects had higher vagal modulation by the three methods (p RSA, but there was no correlation between the T4s and the other two methods. In the group with coronary artery disease, there was a correlation between the results of HRV (pNN50, SDNN, RMSSD, HF ms² and HF n.u.) and RSA. In addition, there was a correlation between the RSA and T4s. Finally, the T4s and RSA methods presented more accurate effect size and better accuracy (p RSA generated partially redundant results in healthy subjects and in patients with coronary artery disease, while the T4s generated results that were complementary to HRV and RSA in healthy subjects. In addition, RSA and T4s methods were more accurate when discriminating cardiac vagal modulation between healthy subjects and patients with coronary artery disease, when compared to HRV.
Bhogal, Sukhdeep; Sethi, Pooja; Taha, Yasir; Papireddy, Muralidhar; Mahajan, Akhilesh; Zaidi, Syed Imran M; Ramu, Vijay; Paul, Timir
Deglutition syncope is a relatively rare cause of syncope that belongs to the category of neurally mediated reflex syncopal syndromes. The phenomenon is related to vagal reflex in context to deglutition causing atrioventricular block and acute reduction in cardiac output leading to dizziness or syncope. We present case series of two cases of deglutition syncope, of which first was managed medically and second with pacemaker implantation.
Bhogal, Sukhdeep; Sethi, Pooja; Taha, Yasir; Papireddy, Muralidhar; Mahajan, Akhilesh; Zaidi, Syed Imran M.; Ramu, Vijay; Paul, Timir
Deglutition syncope is a relatively rare cause of syncope that belongs to the category of neurally mediated reflex syncopal syndromes. The phenomenon is related to vagal reflex in context to deglutition causing atrioventricular block and acute reduction in cardiac output leading to dizziness or syncope. We present case series of two cases of deglutition syncope, of which first was managed medically and second with pacemaker implantation.
Eckberg, D. L.
The human central vagal mechanisms were investigated by measuring the intervals between heartbeats during controlled breathing (at breathing intervals of 2.5-10 s and nominal tidal volumes of 1000 and 1500 ml) in six young men and women. It was found that as the breathing interval increased, the longest heart periods became longer, the shortest heart periods became shorter, and the peak-valley P-P intervals increased asymptotically. Peak-valley intervals also increased in proportion to tidal volume, although this influence was small. The phase angles between heart period changes and respiration were found to vary as linear functions of breathing interval. Heart period shortening began in inspiration at short breathing intervals and in expiration at long breathing intervals, while heart period lengthening began in early expiration at all breathing intervals studied. It is concluded that a close relationship exists between variations of respiratory depth and interval and the quantity, periodicity, and timing of vagal cardiac outflow in conscious humans. The results indicate that at usual breathing rates, phasic respiration-related changes of vagal motoneuron activity begin in expiration, progress slowly, and are incompletely expressed at fast breathing ratges.
Drake, S L; Carunchia Whetstine, M E; Drake, M A; Courtney, P; Fligner, K; Jenkins, J; Pruitt, C
Umami plays an important role in the flavor of many cheese varieties. The purpose of this study was to identify the compound(s) responsible for umami taste in Cheddar and Swiss cheeses. Four Cheddar and 4 Swiss cheeses (two with low umami intensity and two with high umami intensity from each type) were selected using a trained sensory panel. Monosodium glutamate (MSG), disodium 5'-inosine monophosphate (IMP), disodium 5'-guanosine monophosphate (GMP), sodium chloride, lactic acid, propionic acid, and succinic acid were quantified in the cheeses instrumentally. Taste thresholds (best estimate thresholds, BETs) were determined for each compound in water. Subsequently, a trained descriptive sensory analysis panel evaluated each compound in odor-free water across threshold concentrations to confirm that the thresholds were based on umami and not some other stimuli. Model system studies with trained panelists were then conducted with each compound individually or all compounds together. Comparison of analytical data and sensory thresholds indicated that IMP and GMP thresholds were 100-fold higher than their concentrations in cheese. All other compounds contributed some umami taste within their concentration range in umami cheeses. Sensory analysis of model cheeses revealed that glutamic acid played the largest role in umami taste of both Cheddar and Swiss cheeses while succinic and propionic acids contributed to umami taste in Swiss cheeses. Knowledge of the key compounds associated with umami taste in cheeses will aid in the identification of procedures to enhance formation of this taste in cheese.
Full Text Available The satiety inducing hormone leptin acts not only at central nervous system but also at peripheral level. Leptin receptors are found in several sense related organs, including the mouth. A role of leptin in sweet taste response has been suggested but, until now, studies have been based on in vitro experiments, or in assessing the levels of the hormone in circulation. The present study investigated whether the levels of leptin in saliva are related to taste perception in children and whether Body Mass Index (BMI affects such relationship. Sweet and bitter taste sensitivity was assessed for 121 children aged 9-10 years and unstimulated whole saliva was collected for leptin quantification, using ELISA technique. Children females with lower sweet taste sensitivity presented higher salivary leptin levels, but this is only in the normal weight ones. For bitter taste, association between salivary leptin and caffeine threshold detection was observed only in preobese boys, with higher levels of salivary hormone in low sensitive individuals. This study is the first presenting evidences of a relationship between salivary leptin levels and taste perception, which is sex and BMI dependent. The mode of action of salivary leptin at taste receptor level should be elucidated in future studies.
de Araujo, Ivan E.; Geha, Paul
The gustatory aspect of the insular cortex is part of the brain circuit that controls ingestive behaviors based on chemosensory inputs. However, the sensory properties of foods are not restricted to taste and should also include salient features such as odor, texture, temperature, and appearance. Therefore, it is reasonable to hypothesize that specialized circuits within the central taste pathways must be involved in representing several other oral sensory modalities in addition to taste. In this review, we evaluate current evidence indicating that the insular gustatory cortex functions as an integrative circuit, with taste-responsive regions also showing heightened sensitivity to olfactory, somatosensory, and even visual stimulation. We also review evidence for modulation of taste-responsive insular areas by changes in physiological state, with taste-elicited neuronal responses varying according to the nutritional state of the organism. We then examine experimental support for a functional map within the insular cortex that might reflect the various sensory and homeostatic roles associated with this region. Finally, we evaluate the potential role of the taste insular cortex in weight-gain susceptibility. Taken together, the current experimental evidence favors the view that the insular gustatory cortex functions as an orosensory integrative system that not only enables the formation of complex flavor representations but also mediates their modulation by the internal state of the body, playing therefore a central role in food intake regulation. PMID:25485032
Nakagawa, Yuko; Nagasawa, Masahiro; Yamada, Satoko; Hara, Akemi; Mogami, Hideo; Nikolaev, Viacheslav O.; Lohse, Martin J.; Shigemura, Noriatsu; Ninomiya, Yuzo; Kojima, Itaru
Background Sweet taste receptor is expressed in the taste buds and enteroendocrine cells acting as a sugar sensor. We investigated the expression and function of the sweet taste receptor in MIN6 cells and mouse islets. Methodology/Principal Findings The expression of the sweet taste receptor was determined by RT–PCR and immunohistochemistry. Changes in cytoplasmic Ca2+ ([Ca2+]c) and cAMP ([cAMP]c) were monitored in MIN6 cells using fura-2 and Epac1-camps. Activation of protein kinase C was monitored by measuring translocation of MARCKS-GFP. Insulin was measured by radioimmunoassay. mRNA for T1R2, T1R3, and gustducin was expressed in MIN6 cells. In these cells, artificial sweeteners such as sucralose, succharin, and acesulfame-K increased insulin secretion and augmented secretion induced by glucose. Sucralose increased biphasic increase in [Ca2+]c. The second sustained phase was blocked by removal of extracellular calcium and addition of nifedipine. An inhibitor of inositol(1, 4, 5)-trisphophate receptor, 2-aminoethoxydiphenyl borate, blocked both phases of [Ca2+]c response. The effect of sucralose on [Ca2+]c was inhibited by gurmarin, an inhibitor of the sweet taste receptor, but not affected by a Gq inhibitor. Sucralose also induced sustained elevation of [cAMP]c, which was only partially inhibited by removal of extracellular calcium and nifedipine. Finally, mouse islets expressed T1R2 and T1R3, and artificial sweeteners stimulated insulin secretion. Conclusions Sweet taste receptor is expressed in β-cells, and activation of this receptor induces insulin secretion by Ca2+ and cAMP-dependent mechanisms. PMID:19352508
Full Text Available BACKGROUND: Sweet taste receptor is expressed in the taste buds and enteroendocrine cells acting as a sugar sensor. We investigated the expression and function of the sweet taste receptor in MIN6 cells and mouse islets. METHODOLOGY/PRINCIPAL FINDINGS: The expression of the sweet taste receptor was determined by RT-PCR and immunohistochemistry. Changes in cytoplasmic Ca(2+ ([Ca(2+](c and cAMP ([cAMP](c were monitored in MIN6 cells using fura-2 and Epac1-camps. Activation of protein kinase C was monitored by measuring translocation of MARCKS-GFP. Insulin was measured by radioimmunoassay. mRNA for T1R2, T1R3, and gustducin was expressed in MIN6 cells. In these cells, artificial sweeteners such as sucralose, succharin, and acesulfame-K increased insulin secretion and augmented secretion induced by glucose. Sucralose increased biphasic increase in [Ca(2+](c. The second sustained phase was blocked by removal of extracellular calcium and addition of nifedipine. An inhibitor of inositol(1, 4, 5-trisphophate receptor, 2-aminoethoxydiphenyl borate, blocked both phases of [Ca(2+](c response. The effect of sucralose on [Ca(2+](c was inhibited by gurmarin, an inhibitor of the sweet taste receptor, but not affected by a G(q inhibitor. Sucralose also induced sustained elevation of [cAMP](c, which was only partially inhibited by removal of extracellular calcium and nifedipine. Finally, mouse islets expressed T1R2 and T1R3, and artificial sweeteners stimulated insulin secretion. CONCLUSIONS: Sweet taste receptor is expressed in beta-cells, and activation of this receptor induces insulin secretion by Ca(2+ and cAMP-dependent mechanisms.
This is the summary of two lectures that aim to give an overview of cosmology. I will not try to be too rigorous in derivations, nor to give a full historical overview. The idea is to provide a "taste" of cosmology and some of the interesting topics it covers. The standard cosmological model is presented and I highlight the successes of cosmology over the past decade or so. Keys to the development of the standard cosmological model are observations of the cosmic microwave background and of large-scale structure, which are introduced. Inflation and dark energy and the outlook for the future are also discussed. Slides from the lectures are available from the school website: physicschool.web.cern.ch/PhysicSchool/CLASHEP/CLASHEP2011/.
Kwong, Kevin; Carr, Michael J; Gibbard, Anna; Savage, Tony J; Singh, Kuljit; Jing, Junping; Meeker, Sonya; Undem, Bradley J
Lung vagal sensory fibres are broadly categorized as C fibres (nociceptors) and A fibres (non-nociceptive; rapidly and slowly adapting low-threshold stretch receptors). These afferent fibre types differ in degree of myelination, conduction velocity, neuropeptide content, sensitivity to chemical and mechanical stimuli, as well as evoked reflex responses. Recent studies in nociceptive fibres of the somatosensory system indicated that the tetrodotoxin-resistant (TTX-R) voltage-gated sodium channels (VGSC) are preferentially expressed in the nociceptive fibres of the somatosensory system (dorsal root ganglia). Whereas TTX-R sodium currents have been documented in lung vagal sensory nerves fibres, a rigorous comparison of their expression in nociceptive versus non-nociceptive vagal sensory neurons has not been carried out. Using multiple approaches including patch clamp electrophysiology, immunohistochemistry, and single-cell gene expression analysis in the guinea pig, we obtained data supporting the hypothesis that the TTX-R sodium currents are similarly distributed between nodose ganglion A-fibres and C-fibres innervating the lung. Moreover, mRNA and immunoreactivity for the TTX-R VGSC molecules NaV1.8 and NaV1.9 were present in nearly all neurons. We conclude that contrary to findings in the somatosensory neurons, TTX-R VGSCs are not preferentially expressed in the nociceptive C-fibre population innervating the lungs. PMID:18187475
Full Text Available Taste is unique among sensory systems in its innate association with mechanisms of reward and aversion in addition to its recognition of quality, e.g., sucrose is sweet and preferable, and quinine is bitter and aversive. Taste information is sent to the reward system and feeding center via the prefrontal cortices such as the mediodorsal and ventrolateral prefrontal cortices in rodents and the orbitofrontal cortex in primates. The amygdala, which receives taste inputs, also influences reward and feeding. In terms of neuroactive substances, palatability is closely related to benzodiazepine derivatives and β-endorphin, both of which facilitate consumption of food and fluid. The reward system contains the ventral tegmental area, nucleus accumbens and ventral pallidum and finally sends information to the lateral hypothalamic area, the feeding center. The dopaminergic system originating from the ventral tegmental area mediates the motivation to consume palatable food. The actual ingestive behavior is promoted by the orexigenic neuropeptides from the hypothalamus. Even palatable food can become aversive and avoided as a consequence of a postingestional unpleasant experience such as malaise. The neural mechanisms of this conditioned taste aversion will also be elucidated.
Widmann, Annekathrin; Eichler, Katharina; Selcho, Mareike; Thum, Andreas S; Pauls, Dennis
The Drosophila larva is an attractive model system to study fundamental questions in the field of neuroscience. Like the adult fly, the larva offers a seemingly unlimited genetic toolbox, which allows one to visualize, silence or activate neurons down to the single cell level. This, combined with its simplicity in terms of cell numbers, offers a useful system to study the neuronal correlates of complex processes including associative odor-taste learning and memory formation. Here, we summarize the current knowledge about odor-taste learning and memory at the behavioral level and integrate the recent progress on the larval connectome to shed light on the sub-circuits that allow Drosophila larvae to integrate present sensory input in the context of past experience and to elicit an appropriate behavioral response. Copyright © 2017 Elsevier Ltd. All rights reserved.
Medler Kathryn F
Full Text Available Abstract Background Taste receptor cells are responsible for transducing chemical stimuli from the environment and relaying information to the nervous system. Bitter, sweet and umami stimuli utilize G-protein coupled receptors which activate the phospholipase C (PLC signaling pathway in Type II taste cells. However, it is not known how these cells communicate with the nervous system. Previous studies have shown that the subset of taste cells that expresses the T2R bitter receptors lack voltage-gated Ca2+ channels, which are normally required for synaptic transmission at conventional synapses. Here we use two lines of transgenic mice expressing green fluorescent protein (GFP from two taste-specific promoters to examine Ca2+ signaling in subsets of Type II cells: T1R3-GFP mice were used to identify sweet- and umami-sensitive taste cells, while TRPM5-GFP mice were used to identify all cells that utilize the PLC signaling pathway for transduction. Voltage-gated Ca2+ currents were assessed with Ca2+ imaging and whole cell recording, while immunocytochemistry was used to detect expression of SNAP-25, a presynaptic SNARE protein that is associated with conventional synapses in taste cells. Results Depolarization with high K+ resulted in an increase in intracellular Ca2+ in a small subset of non-GFP labeled cells of both transgenic mouse lines. In contrast, no depolarization-evoked Ca2+ responses were observed in GFP-expressing taste cells of either genotype, but GFP-labeled cells responded to the PLC activator m-3M3FBS, suggesting that these cells were viable. Whole cell recording indicated that the GFP-labeled cells of both genotypes had small voltage-dependent Na+ and K+ currents, but no evidence of Ca2+ currents. A subset of non-GFP labeled taste cells exhibited large voltage-dependent Na+ and K+ currents and a high threshold voltage-gated Ca2+ current. Immunocytochemistry indicated that SNAP-25 was expressed in a separate population of taste cells
Christensen, Jacob Højgaard
of expectations to students’ learning. This article presents the results of a new quantitative study that investigates students’ work with taste in relation to their own expected learning in the subject Food Knowledge, viewed in the light of three didactic elements: motivation, student participation...... and innovation in school. The method is a questionnaire among students (N= 769) who have competed in Food Fight, a competition that forms part of Food Knowledge. The connection between taste and learning is a relatively unexplored field, and the analysis in this article indicates that the experience of working...... with taste in Food Knowledge may have an effect on students’ expected learning that is equally positive – or even more so – as that of known didactic elements like student participation and innovation. Therefore, teachers need to create balance between didactic elements and remember to incorporate taste...
Wistoft, Karen; Christensen, Jacob
of expectations to students’ learning. This article presents the results of a new quantitative study that investigates students’ work with taste in relation to their own expected learning in the subject Food Knowledge, viewed in the light of three didactic elements: motivation, student participation...... and innovation in school. The method is a questionnaire among students (N= 769) who have competed in Food Fight, a competition that forms part of Food Knowledge. The connection between taste and learning is a relatively unexplored field, and the analysis in this article indicates that the experience of working...... with taste in Food Knowledge may have an effect on students’ expected learning that is equally positive – or even more so – as that of known didactic elements like student participation and innovation. Therefore, teachers need to create balance between didactic elements and remember to incorporate taste...
Freeman, Erica Gene; Dahanukar, Anupama
Drosophila is a powerful model in which to study the molecular and cellular basis of taste coding. Flies sense tastants via populations of taste neurons that are activated by compounds of distinct categories. The past few years have borne witness to studies that define the properties of taste neurons, identifying functionally distinct classes of sweet and bitter taste neurons that express unique subsets of gustatory receptor (Gr) genes, as well as water, salt, and pheromone sensing neurons that express members of the pickpocket (ppk) or ionotropic receptor (Ir) families. There has also been significant progress in terms of understanding how tastant information is processed and conveyed to higher brain centers, and modulated by prior dietary experience or starvation. Copyright © 2015. Published by Elsevier Ltd.
Hashiba, Kimberlee A; Wo, Shane R; Yamamoto, Loren G
This study evaluated the taste palatability of liquid clindamycin and acetaminophen products on the market. Subjects rated the palatability of 3 clindamycin suspensions, 1 amoxicillin suspension (tasted twice), an acetaminophen elixir, and an acetaminophen suspension in a randomized blinded fashion on a 0 to 5 scale. Forty-six adults aged 20 to 82 years volunteered for this study. Means (and 95% confidence intervals) were as follows: amoxicillin-first taste 3.6 (3.3-3.9), amoxicillin-second taste 3.5 (3.2-3.7). Clindamycin Rising, Perrigo, Greenstone; 2.0 (1.6-2.5), 3.0 (2.7-3.3), and 2.2 (1.8-2.6), respectively. Acetaminophen elixir 0.6 (0.4-0.8) and acetaminophen suspension 3.4 (3.1-3.6). One clindamycin tasted significantly better than the others. Additionally, although 2 acetaminophen formulations are currently available over-the-counter, the suspension is more palatable and less costly. Medicaid drug programs that perpetuate the use of elixir should change their coverage to save money and provide patients access to better tasting acetaminophen.
Full Text Available Taste preference, a key component of food choice, changes with aging. However, it remains unclear how this occurs. To determine differences in taste preference between rats in different life stages, we examined the consumption of taste solutions and water using a two-bottle test. Male Sprague-Dawley rats of different ages were used: juvenile (3-6 weeks, young adult (8-11 weeks, adult (17-20 weeks, middle-aged (34-37 weeks, and old-aged (69-72 weeks. The intakes of the high and low concentration solutions presented simultaneously were measured. We observed that the old-aged group had lower preference ratios for 0.3 M sucrose and 0.1 M MSG in comparison with other groups. The preference ratio for 0.03 mM QHCl was higher in the middle-aged group than in the three younger groups and higher in the old-aged group than the juvenile group. The taste preferences for HCl and NaCl did not significantly differ among the age groups. The old-aged group tended to prefer high concentrations of sucrose, QHCl, NaCl, and MSG to low concentrations, indicating age-related decline in taste sensitivity. We also aimed to investigate differences between life stages in the electrophysiological responses of the chorda tympani nerve, one of the peripheral gustatory nerves, to taste stimuli. The electrophysiological recordings showed that aging did not alter the function of the chorda tympani nerve. This study showed that aging induced alterations in taste preference. It is likely that these alterations are a result of functional changes in other peripheral taste nerves, the gastrointestinal system, or the central nervous system.
Inui-Yamamoto, Chizuko; Yamamoto, Takashi; Ueda, Katsura; Nakatsuka, Michiko; Kumabe, Shunji; Inui, Tadashi; Iwai, Yasutomo
Taste preference, a key component of food choice, changes with aging. However, it remains unclear how this occurs. To determine differences in taste preference between rats in different life stages, we examined the consumption of taste solutions and water using a two-bottle test. Male Sprague-Dawley rats of different ages were used: juvenile (3-6 weeks), young adult (8-11 weeks), adult (17-20 weeks), middle-aged (34-37 weeks), and old-aged (69-72 weeks). The intakes of the high and low concentration solutions presented simultaneously were measured. We observed that the old-aged group had lower preference ratios for 0.3 M sucrose and 0.1 M MSG in comparison with other groups. The preference ratio for 0.03 mM QHCl was higher in the middle-aged group than in the three younger groups and higher in the old-aged group than the juvenile group. The taste preferences for HCl and NaCl did not significantly differ among the age groups. The old-aged group tended to prefer high concentrations of sucrose, QHCl, NaCl, and MSG to low concentrations, indicating age-related decline in taste sensitivity. We also aimed to investigate differences between life stages in the electrophysiological responses of the chorda tympani nerve, one of the peripheral gustatory nerves, to taste stimuli. The electrophysiological recordings showed that aging did not alter the function of the chorda tympani nerve. This study showed that aging induced alterations in taste preference. It is likely that these alterations are a result of functional changes in other peripheral taste nerves, the gastrointestinal system, or the central nervous system.
Kumbargere Nagraj, Sumanth; George, Renjith P; Shetty, Naresh; Levenson, David; Ferraiolo, Debra M; Shrestha, Ashish
The sense of taste is very much essential to the overall health of an individual. It is a necessary component to enjoy one's food, which in turn provides nutrition to an individual. Any disturbance in taste perception can hamper quality of life in such patients by influencing their appetite, body weight and psychological well-being. Taste disorders have been treated using different modalities of treatment and there is no consensus for the best intervention. Hence this Cochrane Review was undertaken. This is an update of the Cochrane Review first published in November 2014. To assess the effects of interventions for the management of patients with taste disturbances. Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 4 July 2017); the Cochrane Central Register of Controlled Trials (CENTRAL; 2017 Issue 6) in the Cochrane Library (searched 4 July 2017); MEDLINE Ovid (1946 to 4 July 2017); Embase Ovid (1980 to 4 July 2017); CINAHL EBSCO (1937 to 4 July 2017); and AMED Ovid (1985 to 4 July 2017). The US National Institutes of Health Ongoing Trials Register ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for trials. Abstracts from scientific meetings and conferences were searched on 25 September 2017. No restrictions were placed on the language or date of publication when searching the electronic databases. We included all randomised controlled trials (RCTs) comparing any pharmacological agent with a control intervention or any non-pharmacological agent with a control intervention. We also included cross-over trials in the review. Two pairs of review authors independently, and in duplicate, assessed the quality of trials and extracted data. Wherever possible, we contacted trial authors for additional information. We collected adverse events information from the trials. We included 10 trials (581 participants
We describe the case of a 37-year-old man with a slowly enlarging neck lump and compressive symptoms. He presented to a separate institution 10 years prior where an observational approach was advocated. Following preoperative investigations and embolization, an 11cm vagal schwannoma was excised and vagus nerve was sacrificed. Although conservative management is appropriate for a select patient population, surgical excision is treatment of choice for cervical neurogenic tumours and paraganglionomas and must be considered in young patients or rapidly expanding tumours to avoid compressive symptoms, as in this case.
Landau, Anne M.; Dyve, Suzan; Jakobsen, Steen
Background Vagal nerve stimulation (VNS) emerged as an anti-epileptic therapy, and more recently as a potential antidepressant intervention. Objective/hypothesis We hypothesized that salutary effects of VNS are mediated, at least in part, by augmentation of the inhibitory effects of cortical...... binding potentials for selected brain regions of each animal. Results VNS treatment markedly reduced the binding potential of yohimbine in limbic, thalamic and cortical brain regions, in inverse correlation with the baseline binding potential. Conclusion The result is consistent with release...... of noradrenaline by antidepressant therapy, implying a possible explanation for the antidepressant effect of VNS....
Araújo, C G; Nobrega, A C; Castro, C L
Heart rate response to a short (4 s) bicycle exercise test during maximal inspiratory apnea was used to assess vagal activity (VA). This study aims to evaluate the role of age, sex and physical activity pattern on VA. A total of 148 subjects, divided into athletes (N = 90) and non-athletes (N = 58) were tested. No correlation was found between age (range from 15 to 42 years) and VA in the male and female athletes (P greater than 0.05). No gender effect could be identified. In spite of a slight tendency toward higher VA in athletes, no significant differences could be found between the two groups.
Chai, Jinghua; Zhou, Minliang; Simon, Nirvine; Huang, Liquan
Although inflammatory responses are a critical component in defense against pathogens, too much inflammation is harmful. Mechanisms have evolved to regulate inflammation, including modulation by the anti-inflammatory cytokine interleukin-10 (IL-10). Previously we have shown that taste buds express various molecules involved in innate immune responses, including the proinflammatory cytokine tumor necrosis factor (TNF). Here, using a reporter mouse strain, we show that taste cells also express the anti-inflammatory cytokine IL-10. Remarkably, IL-10 is produced by only a specific subset of taste cells, which are different from the TNF-producing cells in mouse circumvallate and foliate taste buds: IL-10 expression was found exclusively in the G-protein gustducin-expressing bitter receptor cells, while TNF was found in sweet and umami receptor cells as reported previously. In contrast, IL-10R1, the ligand-binding subunit of the IL-10 receptor, is predominantly expressed by TNF-producing cells, suggesting a novel cellular hierarchy for regulating TNF production and effects in taste buds. In response to inflammatory challenges, taste cells can increase IL-10 expression both in vivo and in vitro. These findings suggest that taste buds use separate populations of taste receptor cells that coincide with sweet/umami and bitter taste reception to modulate local inflammatory responses, a phenomenon that has not been previously reported. Furthermore, IL-10 deficiency in mice leads to significant reductions in the number and size of taste buds, as well as in the number of taste receptor cells per taste bud, suggesting that IL-10 plays critical roles in maintaining structural integrity of the peripheral gustatory system. PMID:24523558
Rawal, Shristi; Huedo-Medina, Tania; Hoffman, Howard J.; Swede, Helen; Duffy, Valerie B.
Objective Variation in taste perception and exposure to risk factors of taste alterations have been independently linked with elevated adiposity. Using a laboratory database, we modeled taste-adiposity associations and examined whether taste functioning mediates the association between taste-related risk factors and adiposity. Methods Healthy women (n=407, 35.5?16.9 years) self-reported histories of risk factors of altered taste functioning (tonsillectomy, multiple ear infections, head trauma...
Madsen, Andreas Nygaard; Jelsing, Jacob; van de Wall, Esther H E M
The selective CB1 receptor antagonist rimonabant is a novel weight control agent. Although CB1 receptors and binding sites are present in both the rodent central and peripheral nervous systems, including the afferent vagus nerve, the role of gut afferents in mediating anorexia following CB1R...... blockade is still debated. In the present study we examined rimonabant-induced anorexia in male C57BL/6J mice with subdiaphragmatic vagotomy (VGX) as well as in male Sprague-Dawley rats subjected to either subdiaphragmatic vagal deafferentation (SDA) alone or in combination with a complete celiac...... system, are required for rimonabant to inhibit food intake leading to the hypothesis that centrally located CB1 receptors are the prime mediators of rimonabant-induced anorexia....
Kirino, Masato; Parnes, Jason; Hansen, Anne; Kiyohara, Sadao; Finger, Thomas E.
Taste buds are gustatory endorgans which use an uncommon purinergic signalling system to transmit information to afferent gustatory nerve fibres. In mammals, ATP is a crucial neurotransmitter released by the taste cells to activate the afferent nerve fibres. Taste buds in mammals display a characteristic, highly specific ecto-ATPase (NTPDase2) activity, suggesting a role in inactivation of the neurotransmitter. The purpose of this study was to test whether the presence of markers of purinergic signalling characterize taste buds in anamniote vertebrates and to test whether similar purinergic systems are employed by other exteroceptive chemosensory systems. The species examined include several teleosts, elasmobranchs, lampreys and hagfish, the last of which lacks vertebrate-type taste buds. For comparison, Schreiner organs of hagfish and solitary chemosensory cells (SCCs) of teleosts, both of which are epidermal chemosensory end organs, were also examined because they might be evolutionarily related to taste buds. Ecto-ATPase activity was evident in elongate cells in all fish taste buds, including teleosts, elasmobranchs and lampreys. Neither SCCs nor Schreiner organs show specific ecto-ATPase activity, suggesting that purinergic signalling is not crucial in those systems as it is for taste buds. These findings suggest that the taste system did not originate from SCCs but arose independently in early vertebrates. PMID:23466675
Ramos, Plínio S.; Araújo, Claudio Gil S.
OBJECTIVES: to determine if there are differences in cardiac vagal tone values in non-obese healthy, adult men with and without unfavorable anthropometric characteristics. INTRODUCTION: It is well established that obesity reduces cardiac vagal tone. However, it remains unknown if decreases in cardiac vagal tone can be observed early in non-obese healthy, adult men presenting unfavorable anthropometric characteristics. METHODS: Among 1688 individuals assessed between 2004 and 2008, we selected 118 non-obese (BMI somatotype), a 4-second exercise test to estimate cardiac vagal tone and a maximal cardiopulmonary exercise test to exclude individuals with myocardial ischemia. The same physician performed all procedures. RESULTS: A lower cardiac vagal tone was found for the individuals in the higher quintiles – unfavorable anthropometric characteristics - of BMI (p=0.005), sum of six skinfolds (p=0.037) and waist circumference (p<0.001). In addition, the more endomorphic individuals also presented a lower cardiac vagal tone (p=0.023), while an ectomorphic build was related to higher cardiac vagal tone values as estimated by the 4-second exercise test (r=0.23; p=0.017). CONCLUSIONS: Non-obese and healthy adult men with unfavorable anthropometric characteristics tend to present lower cardiac vagal tone levels. Early identification of this trend by simple protocols that are non-invasive and risk-free, using select anthropometric characteristics, may be clinically useful in a global strategy to prevent cardiovascular disease. PMID:20126345
Puvaneswary, M.; Gani, J. [John Hunter Hospital, New Lambton Heights, Newcastle, NSW (Australia). Departments of Medical Imaging and Surgery; Kalnins, I.K. [Westmead Hospital, Westmead, Sydney NSW (Australia)
Glomus vagale are rare vascular tumours of the paraganglion cells of the vagus nerve, and they usually occur in the carotid space. Tumours can be familial, multicentric, malignant but rarely hormonally active. A rare case is reported of glomus vagale presenting as a supraclavicular mass. Copyright (1998) Blackwell Science Pty Ltd 12 refs., 3 figs.
Umeyama, Masayoshi; Suzaki, Harumi [Showa Univ., Tokyo (Japan). School of Medicine
become dry with associated redness, swelling of the lingual papillae, and coating of the tongue as the radiation dose increased. The increase in gustatory threshold after radiotherapy appeared to depend on the surface area of the tongue included in the field of irradiation. Based on the results of the present study we suggest that impairment of the sense of taste following radiotherapy is attributable to a disorder of the taste buds occurring at the level of the peripheral nervous system. (author)
Rawal, Shristi; Huedo-Medina, Tania B; Hoffman, Howard J; Swede, Helen; Duffy, Valerie B
Variation in taste perception and exposure to risk factors of taste alterations have been independently linked with elevated adiposity. Using a laboratory database, taste-adiposity associations were modeled and examined for whether taste functioning mediates the association between taste-related risk factors and adiposity. Healthy women (n = 407, 35.5 ± 16.9 y) self-reported histories of risk factors of altered taste functioning (tonsillectomy, multiple ear infections, head trauma) and were assessed for taste functioning (tongue-tip and whole-mouth intensities of quinine and salt) and density of taste papillae. Twenty-four percent had elevated waist circumferences; thirty-nine percent had overweight or obesity. Using structural equation modeling, direct and indirect associations between taste-related risk factors, taste functioning, and adiposity were tested. In models with good fit, elevated central adiposity was explained directly by history of risk factors (tonsillectomy, multiple ear infections) and directly by lower taste functioning (lower tongue-tip taste function, lower papillae density). Risk factors of taste alterations were significantly associated with lower taste functioning, with taste mediating the association between head trauma and reduced adiposity. This large laboratory-based study supports associations between taste-related risk factors, taste functioning, and adiposity. These findings need to be confirmed with other population-based studies, including the National Health and Nutrition Examination Survey 2013-2014 taste data. © 2017 The Obesity Society.
Full Text Available Chemotherapy-induced taste disorder is one of the critical issues in cancer therapy. Bortezomib, a proteasome inhibitor, is a key agent in multiple myeloma therapy, but it induces a taste disorder. In this study, we investigated the characteristics of bortezomib-induced taste disorder and the underlying mechanism in mice. Among the five basic tastes, the sour taste sensitivity of mice was significantly increased by bortezomib administration. In bortezomib-administered mice, protein expression of PKD2L1 was increased. The increased sour taste sensitivity induced by bortezomib returned to the control level on cessation of its administration. These results suggest that an increase in protein expression of PKD2L1 enhances the sour taste sensitivity in bortezomib-administered mice, and this alteration is reversed on cessation of its administration. Keywords: Taste disorder, Bortezomib, Sour taste, Chemotherapy, Adverse effect
Full Text Available The sense of taste is a key component of the sensory machinery, enabling the evaluation of both the safety as well as forming associations regarding the nutritional value of ingestible substances. Indicative of the salience of the modality, taste conditioning can be achieved in rodents upon a single pairing of a tastant with a chemical stimulus inducing malaise. This robust associative learning paradigm has been heavily linked with activity within the insular cortex (IC, among other regions, such as the amygdala and medial prefrontal cortex. A number of studies have demonstrated taste memory formation to be dependent on protein synthesis at the IC and to correlate with the induction of signaling cascades involved in synaptic plasticity. Taste learning has been shown to require the differential involvement of dopaminergic GABAergic, glutamatergic, muscarinic neurotransmission across an extended taste learning circuit. The subsequent activation of downstream protein kinases (ERK, CaMKII, transcription factors (CREB, Elk-1 and immediate early genes (c-fos, Arc, has been implicated in the regulation of the different phases of taste learning. This review discusses the relevant neurotransmission, molecular signaling pathways and genetic markers involved in novel and aversive taste learning, with a particular focus on the IC. Imaging and other studies in humans have implicated the IC in the pathophysiology of a number of cognitive disorders. We conclude that the IC participates in circuit-wide computations that modulate the interception and encoding of sensory information, as well as the formation of subjective internal representations that control the expression of motivated behaviors.
Perry, Nicole B; Calkins, Susan D; Nelson, Jackie A; Leerkes, Esther M; Marcovitch, Stuart
The current study examined the moderating effect of children's cardiac vagal suppression on the association between maternal socialization of negative emotions (supportive and nonsupportive responses) and children's emotion regulation behaviors. One hundred and ninety-seven 4-year-olds and their mothers participated. Mothers reported on their reactions to children's negative emotions and children's regulatory behaviors. Observed distraction, an adaptive self-regulatory strategy, and vagal suppression were assessed during a laboratory task designed to elicit frustration. Results indicated that children's vagal suppression moderated the association between mothers' nonsupportive emotion socialization and children's emotion regulation behaviors such that nonsupportive reactions to negative emotions predicted lower observed distraction and lower reported emotion regulation behaviors when children displayed lower levels of vagal suppression. No interaction was found between supportive maternal emotion socialization and vagal suppression for children's emotion regulation behaviors. Results suggest physiological regulation may serve as a buffer against nonsupportive emotion socialization. Copyright © 2011 Wiley Periodicals, Inc.
Shim, Jaewon; Son, Hee Jin; Kim, Yiseul; Kim, Ki Hwa; Kim, Jung Tae; Moon, Hana; Kim, Min Jung; Misaka, Takumi; Rhyu, Mee-Ra
Although the five basic taste qualities-sweet, sour, bitter, salty and umami-can be recognized by the respective gustatory system, interactions between these taste qualities are often experienced when food is consumed. Specifically, the umami taste has been investigated in terms of whether it enhances or reduces the other taste modalities. These studies, however, are based on individual perception and not on a molecular level. In this study we investigated umami-sweet taste interactions using umami compounds including monosodium glutamate (MSG), 5'-mononucleotides and glutamyl-dipeptides, glutamate-glutamate (Glu-Glu) and glutamate-aspartic acid (Glu-Asp), in human sweet taste receptor hT1R2/hT1R3-expressing cells. The sensitivity of sucrose to hT1R2/hT1R3 was significantly attenuated by MSG and umami active peptides but not by umami active nucleotides. Inhibition of sweet receptor activation by MSG and glutamyl peptides is obvious when sweet receptors are activated by sweeteners that target the extracellular domain (ECD) of T1R2, such as sucrose and acesulfame K, but not by cyclamate, which interact with the T1R3 transmembrane domain (TMD). Application of umami compounds with lactisole, inhibitory drugs that target T1R3, exerted a more severe inhibitory effect. The inhibition was also observed with F778A sweet receptor mutant, which have the defect in function of T1R3 TMD. These results suggest that umami peptides affect sweet taste receptors and this interaction prevents sweet receptor agonists from binding to the T1R2 ECD in an allosteric manner, not to the T1R3. This is the first report to define the interaction between umami and sweet taste receptors.
Full Text Available Although the five basic taste qualities-sweet, sour, bitter, salty and umami-can be recognized by the respective gustatory system, interactions between these taste qualities are often experienced when food is consumed. Specifically, the umami taste has been investigated in terms of whether it enhances or reduces the other taste modalities. These studies, however, are based on individual perception and not on a molecular level. In this study we investigated umami-sweet taste interactions using umami compounds including monosodium glutamate (MSG, 5'-mononucleotides and glutamyl-dipeptides, glutamate-glutamate (Glu-Glu and glutamate-aspartic acid (Glu-Asp, in human sweet taste receptor hT1R2/hT1R3-expressing cells. The sensitivity of sucrose to hT1R2/hT1R3 was significantly attenuated by MSG and umami active peptides but not by umami active nucleotides. Inhibition of sweet receptor activation by MSG and glutamyl peptides is obvious when sweet receptors are activated by sweeteners that target the extracellular domain (ECD of T1R2, such as sucrose and acesulfame K, but not by cyclamate, which interact with the T1R3 transmembrane domain (TMD. Application of umami compounds with lactisole, inhibitory drugs that target T1R3, exerted a more severe inhibitory effect. The inhibition was also observed with F778A sweet receptor mutant, which have the defect in function of T1R3 TMD. These results suggest that umami peptides affect sweet taste receptors and this interaction prevents sweet receptor agonists from binding to the T1R2 ECD in an allosteric manner, not to the T1R3. This is the first report to define the interaction between umami and sweet taste receptors.
Kim, Yiseul; Kim, Ki Hwa; Kim, Jung Tae; Moon, Hana; Kim, Min Jung; Misaka, Takumi; Rhyu, Mee-Ra
Although the five basic taste qualities—sweet, sour, bitter, salty and umami—can be recognized by the respective gustatory system, interactions between these taste qualities are often experienced when food is consumed. Specifically, the umami taste has been investigated in terms of whether it enhances or reduces the other taste modalities. These studies, however, are based on individual perception and not on a molecular level. In this study we investigated umami-sweet taste interactions using umami compounds including monosodium glutamate (MSG), 5’-mononucleotides and glutamyl-dipeptides, glutamate-glutamate (Glu-Glu) and glutamate-aspartic acid (Glu-Asp), in human sweet taste receptor hT1R2/hT1R3-expressing cells. The sensitivity of sucrose to hT1R2/hT1R3 was significantly attenuated by MSG and umami active peptides but not by umami active nucleotides. Inhibition of sweet receptor activation by MSG and glutamyl peptides is obvious when sweet receptors are activated by sweeteners that target the extracellular domain (ECD) of T1R2, such as sucrose and acesulfame K, but not by cyclamate, which interact with the T1R3 transmembrane domain (TMD). Application of umami compounds with lactisole, inhibitory drugs that target T1R3, exerted a more severe inhibitory effect. The inhibition was also observed with F778A sweet receptor mutant, which have the defect in function of T1R3 TMD. These results suggest that umami peptides affect sweet taste receptors and this interaction prevents sweet receptor agonists from binding to the T1R2 ECD in an allosteric manner, not to the T1R3. This is the first report to define the interaction between umami and sweet taste receptors. PMID:25853419
Hamdan Rami Abou
Full Text Available Evaluating individual aerobic exercise capacity is fundamental in sports and exercise medicine but associated with organizational and instrumental effort. Here, we extract an index related to common performance markers, the aerobic and anaerobic thresholds enabling the estimation of exercise capacity from a conventional sports watch supporting beatwise heart rate tracking. Therefore, cardiac vagal threshold (CVT was determined in 19 male subjects performing an incremental maximum exercise test. CVT varied around the anaerobic threshold AnT with mean deviation of 7.9 ± 17.7 W. A high correspondence of the two thresholds was indicated by Bland-Altman plots with limits of agreement −27.5 W and 43.4 W. Additionally, CVT was strongly correlated AnT (rp = 0.86, p < 0.001 and reproduced this marker well (rc = 0.81. We conclude, that cardiac vagal threshold derived from compression entropy time course can be useful to assess physical fitness in an uncomplicated way.
Santa-Cruz Calvo, Sara; Egan, Josephine M.
Levels of obesity have reached epidemic proportions on a global scale, which has led to considerable increases in health problems and increased risk of several diseases, including cardiovascular and pulmonary diseases, cancer and diabetes mellitus. People with obesity consume more food than is needed to maintain an ideal body weight, despite the discrimination that accompanies being overweight and the wealth of available information that overconsumption is detrimental to health. The relationship between energy expenditure and energy intake throughout an individual’s lifetime is far more complicated than previously thought. An improved comprehension of the relationships between taste, palatability, taste receptors and hedonic responses to food might lead to increased understanding of the biological underpinnings of energy acquisition, as well as why humans sometimes eat more than is needed and more than we know is healthy. This Review discusses the role of taste receptors in the tongue, gut, pancreas and brain and their hormonal involvement in taste perception, as well as the relationship between taste perception, overeating and the development of obesity. PMID:25707779
Yu Qing Low
Full Text Available Increased energy consumption, especially increased consumption of sweet energy-dense food, is thought to be one of the main contributors to the escalating rates in overweight individuals and obesity globally. The individual’s ability to detect or sense sweetness in the oral cavity is thought to be one of many factors influencing food acceptance, and therefore, taste may play an essential role in modulating food acceptance and/or energy intake. Emerging evidence now suggests that the sweet taste signaling mechanisms identified in the oral cavity also operate in the gastrointestinal system and may influence the development of satiety. Understanding the individual differences in detecting sweetness in both the oral and gastrointestinal system towards both caloric sugar and high intensity sweetener and the functional role of the sweet taste system may be important in understanding the reasons for excess energy intake. This review will summarize evidence of possible associations between the sweet taste mechanisms within the oral cavity, gastrointestinal tract and the brain systems towards both caloric sugar and high intensity sweetener and sweet taste function, which may influence satiation, satiety and, perhaps, predisposition to being overweight and obesity.
Neural control of left ventricular contractility in the dog heart: synaptic interactions of negative inotropic vagal preganglionic neurons in the nucleus ambiguus with tyrosine hydroxylase immunoreactive terminals.
Massari, V J; Dickerson, L W; Gray, A L; Lauenstein, J M; Blinder, K J; Newsome, J T; Rodak, D J; Fleming, T J; Gatti, P J; Gillis, R A
Recent physiological evidence indicates that vagal postganglionic control of left ventricular contractility is mediated by neurons found in a ventricular epicardial fat pad ganglion. In the dog this region has been referred to as the cranial medial ventricular (CMV) ganglion [J.L. Ardell, Structure and function of mammalian intrinsic cardiac neurons, in: J.A. Armour, J.L. Ardell (Eds.). Neurocardiology, Oxford Univ. Press, New York, 1994, pp. 95-114; B.X. Yuan, J.L. Ardell, D.A. Hopkins, A.M. Losier, J.A. Armour, Gross and microscopic anatomy of the canine intrinsic cardiac nervous system, Anat. Rec., 239 (1994) 75-87]. Since activation of the vagal neuronal input to the CMV ganglion reduces left ventricular contractility without influencing cardiac rate or AV conduction, this ganglion contains a functionally selective pool of negative inotropic parasympathetic postganglionic neurons. In the present report we have defined the light microscopic distribution of preganglionic negative inotropic neurons in the CNS which are retrogradely labeled from the CMV ganglion. Some tissues were also processed for the simultaneous immunocytochemical visualization of tyrosine hydroxylase (TH: a marker for catecholaminergic neurons) and examined with both light microscopic and electron microscopic methods. Histochemically visualized neurons were observed in a long slender column in the ventrolateral nucleus ambiguus (NA-VL). The greatest number of retrogradely labeled neurons were observed just rostral to the level of the area postrema. TH perikarya and dendrites were commonly observed interspersed with vagal motoneurons in the NA-VL. TH nerve terminals formed axo-dendritic synapses upon negative inotropic vagal motoneurons, however the origin of these terminals remains to be determined. We conclude that synaptic interactions exist which would permit the parasympathetic preganglionic vagal control of left ventricular contractility to be modulated monosynaptically by
Honda, Kotaro; Tomooka, Yasuhiro
An improved organ culture system allowed to observe morphogenesis of mouse lingual papillae and taste buds relatively for longer period, in which fetal tongues were analyzed for 6 d. Taste cells were defined as eosinophobic epithelial cells expressing CK8 and Sox2 within lingual epithelium. Addition of glycogen synthase kinase 3 beta inhibitor CHIR99021 induced many taste cells and buds in non-gustatory and gustatory stratified lingual epithelium. The present study clearly demonstrated induction of taste cells and buds ectopically and without innervation.
Bitter tastes are among the most salient of life's experiences--who can forget one's first encounter with dandelion milk or a stout beer? Studies of the genes underlying these tastes are providing new perspectives on human origins and health.
Flores, Veronica L.; Moran, Anan; Bernstein, Max; Katz, Donald B.
Conditioned taste aversion (CTA) is an intensively studied single-trial learning paradigm whereby animals are trained to avoid a taste that has been paired with malaise. Many factors influence the strength of aversion learning; prominently studied among these is taste novelty--the fact that preexposure to the taste conditioned stimulus (CS)…
玉木, 雅子; 鵜飼, 光子; Masako, TAMAKI; Mitsuko, UKAI
Soak process of food was used commonly for vegetables to take away odor, harshness and color. In this study, the effect of soak on the properties and tastes of onion were investigated. In soaking onion with water, the bitter and hot taste in the slice decreased, and stimulus taste softened. In addition, the odor specific to the raw onion slice decreased after soaking with water. For texture characteristics, the onion soaked water was softer and less fibrous. The properties and tastes of water...
Barlow, Linda A.; Klein, Ophir D.
Taste is one of the fundamental senses, and it is essential for our ability to ingest nutritious substances and to detect and avoid potentially toxic ones. Taste buds, which are clusters of neuroepithelial receptor cells, are housed in highly organized structures called taste papillae in the oral cavity. Whereas the overall structure of the taste periphery is conserved in almost all vertebrates examined to date, the anatomical, histological, and cell biological, as well as potentially the mol...
Bloomquist, R.F.; Parnell, N; Phillips, K A; Fowler, T E; Yu, Tian; Sharpe, Paul T.; Streelman, J T
Teeth and taste buds are iteratively patterned structures that line the oro-pharynx of vertebrates. Biologists do not fully understand how teeth and taste buds develop from undifferentiated epithelium or how variation in organ density is regulated. These organs are typically studied independently because of their separate anatomical location in mammals: teeth on the jaw margin and taste buds on the tongue. However, in many aquatic animals like bony fishes, teeth and taste buds are colocalized...
Schelegle, E.S.; Carl, M.L.; Coleridge, H.M.; Coleridge, J.C.; Green, J.F. (Univ. of California, Davis (United States))
Acute inhalation of ozone induces vagally mediated rapid shallow breathing and bronchoconstriction. In spontaneously breathing anesthetized dogs, we attempted to determine whether afferent vagal C-fibers in the lower airways contributed to these responses. Dogs inhaled 3 ppm ozone for 40-70 min into the lower trachea while cervical vagal temperature was maintained successively at 37, 7, and 0 degrees C. At 37 degrees C, addition of ozone to the inspired air decreased tidal volume and dynamic lung compliance and increased breathing frequency, total lung resistance, and tracheal smooth muscle tension. Ozone still evoked significant effects when conduction in myelinated vagal axons was blocked selectively by cooling the nerves to 7 degrees C. Ozone-induced effects were largely abolished when nonmyelinated vagal axons were blocked by cooling to 0 degree C, breathing during ozone inhalation at 0 degree C being generally similar to that during air breathing at 0 degree C, except that minute volume and inspiratory flow were higher. We conclude that afferent vagal C-fibers in the lower airways make a major contribution to the acute respiratory effects of ozone and that nonvagal afferents contribute to the effects that survive vagal blockade.
Full Text Available Selective vagal nerve stimulation (sVNS has been demonstrated to lower blood pressure (BP in rats without causing major side effects. This method might be adapted for the treatment of therapy-resistant hypertension in patients. Converting enzyme inhibitors (CEIs are among the first drugs that are administered for arterial hypertension and prominently reduce BP primarily by interacting with the renin-angiotensin system of the kidneys. Beyond the reduction of BP, CEI have a positive effect on the survival rate after myocardial infarction; they reduce the rates of stroke and improve the neurohormonal status in heart-failure patients. If sVNS might be introduced as a therapy against resistant hypertension, patients will at least partially stay on their CEI medication. It is therefore the aim of this study to investigate the influence of the CEI enalapril on the haemodynamic and respiratory effects of sVNS. In 10 male Wistar rats, a polyimide-based multichannel-cuff-electrode was placed around the vagal nerve bundle to selectively stimulate the aortic depressor nerve fibres. Stimulation parameters were adapted to the thresholds of the individual animals and included repetition frequencies between 30 and 50 Hz, amplitudes of 0.5 to 1.5 mA and pulse widths between 0.4 ms and 1.0 ms. BP responses were detected with a microtip transducer in the left carotid artery, and electrocardiography was recorded with subcutaneous electrodes. After intravenous administration of enalapril (2 mg/kg bodyweight, the animals' mean arterial blood pressures (MAPs decreased significantly, while the heart rates (HRs were not significantly influenced. The effects of sVNS on BP and HR were attenuated by enalapril but were still present. We conclude that sVNS can lower the MAP during enalapril treatment without relevant side effects.
Kinnamon, Sue C; Vandenbeuch, Aurelie
L-glutamate and 5'-ribonucleotides, such as GMP and IMP, elicit the "umami" taste, also known as the fifth taste. This review will highlight recent advancements in our understanding of umami taste receptors and their downstream signaling effectors in taste receptor cells. Several G protein-coupled receptors that bind umami stimuli have been identified in taste buds, including the heterodimer T1R1/T1R3, truncated and brain forms of mGluR4 and mGluR1, brain mGluR2, and brain mGluR3. Further, ionotropic glutamate receptors are expressed in taste cells and may play a role in glutamate transduction or signaling between taste cells and/or nerve fibers. Knockout of T1R1 or T1R3 reduces, but does not eliminate, responses to umami stimuli, suggesting that multiple receptors contribute to umami taste. The signaling effectors downstream of umami G protein-coupled receptors involve Gbetagamma activation of PLCbeta2 to elicit Ca(2+) release from intracellular stores and activation of a cation channel, TRPM5. In fungiform and palatal taste buds, T1R1/T1R3 is co-expressed with Galpha gustducin and transducin, but the Galpha proteins involved in circumvallate taste buds have not been identified. In most taste fields, however, cAMP antagonizes responses to umami stimuli, suggesting that the Galpha subunit serves to modulate umami taste sensitivity.
Barlow, Linda A.; Klein, Ophir D.
Taste is one of the fundamental senses, and it is essential for our ability to ingest nutritious substances and to detect and avoid potentially toxic ones. Taste buds, which are clusters of neuroepithelial receptor cells, are housed in highly organized structures called taste papillae in the oral cavity. Whereas the overall structure of the taste periphery is conserved in almost all vertebrates examined to date, the anatomical, histological, and cell biological, as well as potentially the molecular details of taste buds in the oral cavity are diverse across species and even among individuals. In mammals, several types of gustatory papillae reside on the tongue in highly ordered arrangements, and the patterning and distribution of the mature papillae depends on coordinated molecular events in embryogenesis. In this review, we highlight new findings in the field of taste development, including how taste buds are patterned and how taste cell fate is regulated. We discuss whether a specialized taste bud stem cell population exists and how extrinsic signals can define which cell lineages are generated. We also address the question of whether molecular regulation of taste cell renewal is analogous to that of taste bud development. Finally, we conclude with suggestions for future directions, including the potential influence of the maternal diet and maternal health on the sense of taste in utero. PMID:25662267
The ability to taste Phenylthiocarbamide (PTC), a bitter organic compound has been described as a bimodal autosomal trait in both genetic and anthropological studies. This study is based on the ability of a person to taste PTC. The present study reports the threshold distribution of PTC taste sensitivity among some Muslim ...
Barlow, Linda A; Klein, Ophir D
Taste is one of the fundamental senses, and it is essential for our ability to ingest nutritious substances and to detect and avoid potentially toxic ones. Taste buds, which are clusters of neuroepithelial receptor cells, are housed in highly organized structures called taste papillae in the oral cavity. Whereas the overall structure of the taste periphery is conserved in almost all vertebrates examined to date, the anatomical, histological, and cell biological, as well as potentially the molecular details of taste buds in the oral cavity are diverse across species and even among individuals. In mammals, several types of gustatory papillae reside on the tongue in highly ordered arrangements, and the patterning and distribution of the mature papillae depend on coordinated molecular events in embryogenesis. In this review, we highlight new findings in the field of taste development, including how taste buds are patterned and how taste cell fate is regulated. We discuss whether a specialized taste bud stem cell population exists and how extrinsic signals can define which cell lineages are generated. We also address the question of whether molecular regulation of taste cell renewal is analogous to that of taste bud development. Finally, we conclude with suggestions for future directions, including the potential influence of the maternal diet and maternal health on the sense of taste in utero. © 2015 Elsevier Inc. All rights reserved.
Kim, Min Jung; Son, Hee Jin; Kim, Yiseul; Misaka, Takumi; Rhyu, Mee-Ra
Taste-taste interactions often showed in human psychophysical studies. Considering that each tastant in foodstuffs individually stimulates its responsible gustatory systems to elicit relevant taste modalities, taste-taste interaction should be performed in taste receptor cell-based assay. While umami substances have been proposed to suppress the bitterness of various chemicals in human sensory evaluation, the bitter-umami interaction has not been explored in bitter taste receptors, TAS2Rs. We investigated umami-bitter taste interactions by presenting umami peptides with bitter substance (salicin) on Ca(2+)-flux signaling assay using hTAS2R16-expressing cells. Five representative umami peptides (Glu-Asp, Glu-Glu, Glu-Ser, Asp-Glu-Ser, and Glu-Gly-Ser) derived from soybean markedly attenuated the salicin-induced intracellular calcium influx in a time-dependent manner, respectively, while Gly-Gly, a tasteless peptide did not. The efficacies of Glu-Glu suppressing salicin-induced activation of hTAS2R16 were higher than that of probenecid, a specific antagonist of hTAS2R16. According to Ca(2+)-flux signaling assay using the mixtures of salicin and umami peptides, all five umami peptides suppressed salicin-induced intracellular calcium influx in a noncompetitive manner. These results may provide evidence that umami peptides suppress bitter taste via bitter taste receptor(s). This is the first report which defines the interaction between bitter and umami taste in taste receptor level. Copyright © 2014. Published by Elsevier Inc.
Home; Journals; Resonance – Journal of Science Education; Volume 12; Issue 8. A Taste of Functional Programming – I. Madhavan Mukund. General Article Volume 12 Issue 8 August 2007 pp 27-48. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/012/08/0027-0048 ...
Vries, de Yfke Carlijn
Taste and smell changes are common side effects during chemotherapy in cancer patient and may have an impact on food preferences, food intake and quality of life. However, these relations have hardly been studied systematically in specific cancer populations. The overall aim of this thesis was to
Erickson, John Edward
To test whether student tastes in poetry could be modified by a particular method of teaching it, the poetic preferences of 751 eighth grade students were pretested and compared with the poetic choices made by a panel of English educators, 35 student teachers in English, and the students' own English teachers. Consistently, poems selected by any…
Yoshimoto, Joto; Okada, Shinji; Kishi, Mikiya; Misaka, Takumi
Taste signals are received by taste buds. To better understand the taste reception system, expression patterns of taste-related molecules are determined by in situ hybridization (ISH) analyses at the histological level. Nevertheless, even though ISH is essential for determining mRNA expression, few taste bud markers can be applied together with ISH. Ulex europaeus agglutinin-1 (UEA-1) appears to be a reliable murine taste bud marker based on immunohistochemistry (IHC) analyses. However, there is no evidence as to whether UEA-1 can be used for ISH. Thus, the present study evaluated UEA-1 using various histochemical methods, especially ISH. When lectin staining was performed after ISH procedures, UEA-1 clearly labeled taste cellular membranes and distinctly indicated boundaries between taste buds and the surrounding epithelial cells. Additionally, UEA-1 was determined as a taste bud marker not only when used in single-colored ISH but also when employed with double-labeled ISH or during simultaneous detection using IHC and ISH methods. These results suggest that UEA-1 is a useful marker when conducting analyses based on ISH methods. To clarify UEA-1 staining details, multi-fluorescent IHC (together with UEA-1 staining) was examined, resulting in more than 99% of cells being labeled by UEA-1 and overlapping with KCNQ1-expressing cells. © 2016 The Histochemical Society.
Shams, H.; Daffonchio, L.; Scheid, P.
1. Levodropropizine (LVDP) is an effective antitussive drug. Its effects on single-unit discharge of vagal afferent C-fibres were tested in anaesthetized cats to assess whether an inhibition of vagal C-fibres is involved in its antitussive properties. Vagal C-fibres, identified by their response to phenylbiguanide (PBG), were recorded via suction electrodes from the distal part of the cut vagus. Based on their response to lung inflation, C-fibres were classified as pulmonary (19 fibres) or no...
This paper focus on how taste is used in contemporary food education. Furthermore the focus is how taste is used in a specific food education program in Danish schools. By critically discussing a sample of academic studies that design and evaluate taste education programs for children, the paper...... or a central way of sensually understanding and approaching the world. In other words, taste literacy in general becomes a tool to push children towards ‘hegemonic nutrition’. In addition the paper presents results of a new quantitative study that investigates school students’ work with taste in relation...
Niki, Mayu; Jyotaki, Masafumi; Yoshida, Ryusuke; Yasumatsu, Keiko; Shigemura, Noriatsu; DiPatrizio, Nicholas V; Piomelli, Daniele; Ninomiya, Yuzo
Leptin is an anorexigenic mediator that reduces food intake by acting on hypothalamic receptor Ob-Rb. In contrast, endocannabinoids are orexigenic mediators that act via cannabinoid CB1 receptors in hypothalamus, limbic forebrain, and brainstem. In the peripheral taste system, leptin administration selectively inhibits behavioural, taste nerve and taste cell responses to sweet compounds. Opposing the action of leptin, endocannabinoids enhance sweet taste responses. However, potential roles of endogenous leptin and endocannabinoids in sweet taste remain unclear. Here, we used pharmacological antagonists (Ob-Rb: L39A/D40A/F41A (LA), CB1: AM251) and examined the effects of their blocking activation of endogenous leptin and endocannabinoid signalling on taste responses in lean control, leptin receptor deficient db/db, and diet-induced obese (DIO) mice. Lean mice exhibited significant increases in chorda tympani (CT) nerve responses to sweet compounds after LA administration, while they showed no significant changes in CT responses after AM251. In contrast, db/db mice showed clear suppression of CT responses to sweet compounds after AM251, increased endocannabinoid (2-arachidonoyl-sn-glycerol (2-AG)) levels in the taste organ, and enhanced expression of a biosynthesizing enzyme (diacylglycerol lipase α (DAGLα)) of 2-AG in taste cells. In DIO mice, the LA effect was gradually decreased and the AM251 effect was increased during the course of obesity. Taken together, our results suggest that circulating leptin, but not local endocannabinoids, may be a dominant modulator for sweet taste in lean mice; however, endocannabinoids may become more effective modulators of sweet taste under conditions of deficient leptin signalling, possibly due to increased production of endocannabinoids in taste tissue. Key points Potential roles of endogenous leptin and endocannabinoids in sweet taste were examined by using pharmacological antagonists and mouse models including leptin receptor
Niki, Mayu; Jyotaki, Masafumi; Yoshida, Ryusuke; Yasumatsu, Keiko; Shigemura, Noriatsu; DiPatrizio, Nicholas V; Piomelli, Daniele; Ninomiya, Yuzo
Potential roles of endogenous leptin and endocannabinoids in sweet taste were examined by using pharmacological antagonists and mouse models including leptin receptor deficient (db/db) and diet-induced obese (DIO) mice. Chorda tympani (CT) nerve responses of lean mice to sweet compounds were increased after administration of leptin antagonist (LA) but not affected by administration of cannabinoid receptor antagonist (AM251). db/db mice showed clear suppression of CT responses to sweet compounds after AM251, increased endocannabinoid levels in the taste organ, and enhanced expression of a biosynthesizing enzyme of endocannabinoids in taste cells. The effect of LA was gradually decreased and that of AM251 was increased during the course of obesity in DIO mice. These findings suggest that circulating leptin, but not local endocannabinoids, is a dominant modulator for sweet taste in lean mice and endocannabinoids become more effective modulators of sweet taste under conditions of deficient leptin signalling. Leptin is an anorexigenic mediator that reduces food intake by acting on hypothalamic receptor Ob-Rb. In contrast, endocannabinoids are orexigenic mediators that act via cannabinoid CB1 receptors in hypothalamus, limbic forebrain, and brainstem. In the peripheral taste system, leptin administration selectively inhibits behavioural, taste nerve and taste cell responses to sweet compounds. Opposing the action of leptin, endocannabinoids enhance sweet taste responses. However, potential roles of endogenous leptin and endocannabinoids in sweet taste remain unclear. Here, we used pharmacological antagonists (Ob-Rb: L39A/D40A/F41A (LA), CB1 : AM251) and examined the effects of their blocking activation of endogenous leptin and endocannabinoid signalling on taste responses in lean control, leptin receptor deficient db/db, and diet-induced obese (DIO) mice. Lean mice exhibited significant increases in chorda tympani (CT) nerve responses to sweet compounds after LA
Saites, Louis N; Goldsmith, Zachary; Densky, Jaron; Guedes, Vivian A; Boughter, John D
Previous electrophysiological investigation shows that combinations of compounds classified by humans as umami-tasting, such as glutamate salts and 5'-ribonucleotides, elicit synergistic responses in neurons throughout the rodent taste system and produce a pattern that resembles responses to sweet compounds. The current study tested the hypothesis that a synergistic mixture of monopotassium glutamate (MPG) and inositol monophosphate (IMP) possesses perceptual similarity to sucrose in mice. We estimated behavioral similarity among these tastants and the individual umami compounds using a series of conditioned taste aversion (CTA) tests, a procedure that measures whether a CTA formed to one stimulus generalizes to another. Our primary finding was that a CTA to a synergistic mixture of MPG + IMP generalizes to sucrose, and vice-versa. This indicates umami synergistic mixtures are perceived as having a sweet, or at least sucrose-like, taste to mice. Considering other recent studies, our data argue strongly in favor of multiple receptor mechanisms for umami detection, and complexity in taste perception models for rodents. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: firstname.lastname@example.org.
Full Text Available Food color affects taste perception. However, the possible effects of the visual texture of a foodstuff on taste and flavor, without associated changes to color, are currently unknown. We conducted a series of experiments designed to investigate how the visual texture and appearance of food influences its perceived taste and flavor by developing an Augmented Reality system. Participants observed a video of tomato ketchup as a food stimulus on a white dish placed behind a flat LC-display on which was mounted a video camera. The luminance distribution of the ketchup in the dynamic video was continuously and quantitatively modified by tracking specified colors in real-time. We changed the skewness of the luminance histogram of each frame in the video keeping the xy-chromaticity values intact. Participants watched themselves dip a spoon into the ketchup from the video feed (which could be altered, but then ate it with their eyes closed. They reported before and after tasting the ketchup on the perceived consistency (a liquid to solid continuum the food looked and felt and how tasty it looked or felt. The experimental results suggest that visual texture, independent of color, affects the taste and flavor as well as the appearance of foods.
Full Text Available While our understanding of the molecular and cellular aspects of taste reception and signaling continues to improve, the aberrations in these processes that lead to taste dysfunction remain largely unexplored. Abnormalities in taste can develop in a variety of diseases, including infections and autoimmune disorders. In this study, we used a mouse model of autoimmune disease to investigate the underlying mechanisms of taste disorders. MRL/MpJ-Fas(lpr/J (MRL/lpr mice develop a systemic autoimmunity with phenotypic similarities to human systemic lupus erythematosus and Sjögren's syndrome. Our results show that the taste tissues of MRL/lpr mice exhibit characteristics of inflammation, including infiltration of T lymphocytes and elevated levels of some inflammatory cytokines. Histological studies reveal that the taste buds of MRL/lpr mice are smaller than those of wild-type congenic control (MRL/+/+ mice. 5-Bromo-2'-deoxyuridine (BrdU pulse-chase experiments show that fewer BrdU-labeled cells enter the taste buds of MRL/lpr mice, suggesting an inhibition of taste cell renewal. Real-time RT-PCR analyses show that mRNA levels of several type II taste cell markers are lower in MRL/lpr mice. Immunohistochemical analyses confirm a significant reduction in the number of gustducin-positive taste receptor cells in the taste buds of MRL/lpr mice. Furthermore, MRL/lpr mice exhibit reduced gustatory nerve responses to the bitter compound quinine and the sweet compound saccharin and reduced behavioral responses to bitter, sweet, and umami taste substances compared with controls. In contrast, their responses to salty and sour compounds are comparable to those of control mice in both nerve recording and behavioral experiments. Together, our results suggest that type II taste receptor cells, which are essential for bitter, sweet, and umami taste reception and signaling, are selectively affected in MRL/lpr mice, a model for autoimmune disease with chronic
Running, Cordelia A; Craig, Bruce A; Mattes, Richard D
Considerable mechanistic data indicate there may be a sixth basic taste: fat. However, evidence demonstrating that the sensation of nonesterified fatty acids (NEFA, the proposed stimuli for "fat taste") differs qualitatively from other tastes is lacking. Using perceptual mapping, we demonstrate that medium and long-chain NEFA have a taste sensation that is distinct from other basic tastes (sweet, sour, salty, and bitter). Although some overlap was observed between these NEFA and umami taste, this overlap is likely due to unfamiliarity with umami sensations rather than true similarity. Shorter chain fatty acids stimulate a sensation similar to sour, but as chain length increases this sensation changes. Fat taste oral signaling, and the different signals caused by different alkyl chain lengths, may hold implications for food product development, clinical practice, and public health policy. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: email@example.com.
Carey, Ryan M.; Adappa, Nithin D.; Palmer, James N.; Lee, Robert J.
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. PMID:27819057
Shenoy S Vijendra
Full Text Available Cervical vagal schwannoma is an extremely rare neoplasm. Middle aged people are usually affected. These tumors usually present as asymptomatic masses. These tumors are almost always benign. Preoperative diagnosis of these lesions is important due to the morbidity associated with its excision. Preoperative tissue diagnosis is not accurate. The imaging modality can be done to assess the extent and for planning the treatment. Surgical excision with preservation of neural origin is the treatment option. Giant vagal schwannomas are extremely rare. Only one case has been reported in the literature till date. There has no reported case of extensive vagal schwannoma from skull base to the mediastinum. Here, we describe the asymptomatic presentation of an unusual appearing giant cervical vagal schwannoma with an extension from skull base to the mediastinum.
de Lartigue, Guillaume; de La Serre, Claire Barbier; Raybould, Helen E
The vagal afferent pathway is the major neural pathway by which information about ingested nutrients reaches the CNS and influences both GI function and feeding behavior. Vagal afferent neurons (VAN) express receptors for many of the regulatory peptides and molecules released from the intestinal wall, pancreas, and adipocytes that influence GI function, glucose homeostasis, and regulate food intake and body weight. As such, they play a critical role in both physiology and pathophysiology, such as obesity, where there is evidence that vagal afferent function is altered. This review will summarize recent findings on changes in vagal afferent function in response to ingestion of high fat diets and explore the hypothesis that changes in gut microbiota and integrity of the epithelium may not only be important in inducing these changes but may be the initial events that lead to dysregulation of food intake and body weight in response to high fat, high energy diets. Copyright © 2011 Elsevier Inc. All rights reserved.
Fan, Yuan-Yuan; Yu, Dong-Ming; Shi, Yu-Juan; Yan, Jian-Qun; Jiang, En-She
The sensor of the taste is the taste bud. The signals originated from the taste buds are transmitted to the central nervous system through the gustatory taste nerves. The chorda tympani nerve (innervating the taste buds of the anterior tongue) and glossopharyngeal nerve (innervating the taste buds of the posterior tongue) are the two primary gustatory nerves. The injuries of gustatory nerves cause their innervating taste buds atrophy, degenerate and disappear. The related taste function is also impaired. The impaired taste function can be restored after the gustatory nerves regeneration. The rat model of cross-regeneration of gustatory nerves is an important platform for research in the plasticity of the central nervous system. The animal behavioral responses and the electrophysiological properties of the gustatory nerves have changed a lot after the cross-regeneration of the gustatory nerves. The effects of the injury, regeneration and cross-regeneration of the gustatory nerves on the taste function in the animals will be discussed in this review. The prospective studies on the animal model of cross-regeneration of gustatory nerves are also discussed in this review. The study on the injury, regeneration and cross-regeneration of the gustatory nerves not only benefits the understanding of mechanism for neural plasticity in gustatory nervous system, but also will provide theoretical basis and new ideas for seeking methods and techniques to cure dysgeusia.
Plínio S. Ramos
Full Text Available OBJECTIVES: to determine if there are differences in cardiac vagal tone values in non-obese healthy, adult men with and without unfavorable anthropometric characteristics. INTRODUCTION: It is well established that obesity reduces cardiac vagal tone. However, it remains unknown if decreases in cardiac vagal tone can be observed early in non-obese healthy, adult men presenting unfavorable anthropometric characteristics. METHODS: Among 1688 individuals assessed between 2004 and 2008, we selected 118 non-obese (BMI <30 kg/m², healthy men (no known disease conditions or regular use of relevant medications, aged between 20 and 77 years old (42 ± 12-years-old. Their evaluation included clinical examination, anthropometric assessment (body height and weight, sum of six skinfolds, waist circumference and somatotype, a 4-second exercise test to estimate cardiac vagal tone and a maximal cardiopulmonary exercise test to exclude individuals with myocardial ischemia. The same physician performed all procedures. RESULTS: A lower cardiac vagal tone was found for the individuals in the higher quintiles - unfavorable anthropometric characteristics - of BMI (p=0.005, sum of six skinfolds (p=0.037 and waist circumference (p<0.001. In addition, the more endomorphic individuals also presented a lower cardiac vagal tone (p=0.023, while an ectomorphic build was related to higher cardiac vagal tone values as estimated by the 4-second exercise test (r=0.23; p=0.017. CONCLUSIONS: Non-obese and healthy adult men with unfavorable anthropometric characteristics tend to present lower cardiac vagal tone levels. Early identification of this trend by simple protocols that are non-invasive and risk-free, using select anthropometric characteristics, may be clinically useful in a global strategy to prevent cardiovascular disease.
Tomei, Krystal L; Mau, Christine Y; Ghali, Michael; Pak, Jayoung; Goldstein, Ira M
We describe three children with Angelman syndrome and medically refractory epilepsy. Case series of three pediatric patients with Angelman syndrome and medically refractory epilepsy. All three patients failed medical treatment and were recommended for vagal nerve stimulator (VNS) implantation. Following VNS implantation, all three patients experienced reduction in seizure frequency greater than that afforded by medication alone. We present vagal nerve stimulator implantation as a viable treatment option for medically refractory epilepsy associated with Angelman syndrome.
Lemola, Kristina; Chartier, Denis; Yeh, Yung-Hsin; Dubuc, Marc; Cartier, Raymond; Armour, Andrew; Ting, Michael; Sakabe, Masao; Shiroshita-Takeshita, Akiko; Comtois, Philippe; Nattel, Stanley
Pulmonary vein (PV) -encircling radiofrequency ablation frequently is effective in vagal atrial fibrillation (AF), and there is evidence that PVs may be particularly prone to cholinergically induced arrhythmia mechanisms. However, PV ablation procedures also can affect intracardiac autonomic ganglia. The present study examined the relative role of PVs versus peri-PV autonomic ganglia in an experimental vagal AF model. Cholinergic AF was studied under carbachol infusion in coronary perfused canine left atrial PV preparations in vitro and with cervical vagal stimulation in vivo. Carbachol caused dose-dependent AF promotion in vitro, which was not affected by excision of all PVs. Sustained AF could be induced easily in all dogs during vagal nerve stimulation in vivo both before and after isolation of all PVs with encircling lesions created by a bipolar radiofrequency ablation clamp device. PV elimination had no effect on atrial effective refractory period or its responses to cholinergic stimulation. Autonomic ganglia were identified by bradycardic and/or tachycardic responses to high-frequency subthreshold local stimulation. Ablation of the autonomic ganglia overlying all PV ostia suppressed the effective refractory period-abbreviating and AF-promoting effects of cervical vagal stimulation, whereas ablation of only left- or right-sided PV ostial ganglia failed to suppress AF. Dominant-frequency analysis suggested that the success of ablation in suppressing vagal AF depended on the elimination of high-frequency driver regions. Intact PVs are not needed for maintenance of experimental cholinergic AF. Ablation of the autonomic ganglia at the base of the PVs suppresses vagal responses and may contribute to the effectiveness of PV-directed ablation procedures in vagal AF.
Hooper, Justin Shane; Hadley, Stephen H; Mathews, Adithya; Taylor-Clark, Thomas E
Vagal sensory nerves innervate the majority of visceral organs (e.g., heart, lungs, GI tract, etc) and their activation is critical for defensive and regulatory reflexes. Intracellular Ca(2+) is a key regulator of neuronal excitability and is largely controlled by the Ca(2+) stores of the endoplasmic reticulum. In other cell types store-operated channels (SOC) have been shown to contribute to the homeostatic control of intracellular Ca(2+). Here, using Ca(2+) imaging, we have shown that ER depletion in vagal sensory neurons (using thapsigargin or caffeine) in the absence of extracellular Ca(2+) evoked Ca(2+) influx upon re-introduction of Ca(2+) into the extracellular buffer. This store-operated Ca(2+) entry (SOCE) was observed in approximately 25-40% of vagal neurons, equally distributed among nociceptive and non-nociceptive sensory subtypes. SOCE was blocked by Gd(3+) but not by the Orai channel blocker SKF96365. We found Orai channel mRNA in extracts from whole vagal ganglia, but when using single cell RT-PCR analysis we found only 3 out of 34 neurons expressed Orai channel mRNA, indicating that Orai channel expression in the vagal ganglia was likely derived from non-neuronal cell types. Confocal microscopy of vagal neurons in 3 day cultures demonstrated rich ER tracker fluorescence throughout axonal and neurite structures and ER store depletion (thapsigargin) evoked Ca(2+) transients from these structures. However, no SOCE could be detected in the axonal/neurite structures of vagal neurons. We conclude that SOCE occurs in vagal sensory neuronal cell bodies through non-Orai mechanisms but is absent at nerve terminals. Copyright © 2013 Elsevier B.V. All rights reserved.
Patel, Mira A; Eytan, Danielle F; Bishop, Justin; Califano, Joseph A
Objective To determine the impact of unilateral vagal sacrifice for vagal schwannoma on postoperative swallowing function. Study Design Case series, chart review. Setting Academic medical institution. Subjects and Methods Ten patients underwent vagus nerve sacrifice for vagal schwannoma resection. Archived pathology records dating from 1985 through 2012 at our institution were retrospectively queried for cases of vagal schwannoma with vagus nerve sacrifice. Medical records were abstracted for demographic and disease information as well as cranial nerve and swallowing function. Preoperative and postoperative cranial nerve function, subjective and objective measures of swallowing function, Functional Oral Intake Scale (FOIS) level, and need for vocal fold medialization were variables collected. Data were analyzed with summary statistics. Results The patients who underwent vagal sacrifice for vagal schwannoma at our institution had a mean age of 42.3 years (median, 44 years; range, 15-63 years) and follow-up of 35.6 months (median, 9 months; range, 1-115 months). Most presented with no preoperative cranial nerve deficit or difficulty swallowing. Immediately postoperatively, 90% had a vagus nerve deficit, but 50% had no subjective difficulty swallowing, and 70% had a FOIS level of 7 at postoperative hospital discharge. Within 1 month after surgery, 70% had normal swallowing function according to a modified barium swallow study. A full diet was tolerated by mouth within an average of 2.7 days (median, 2 days; range, 1-6 days) after surgery in this cohort. Seventy percent required vocal fold medialization postoperatively for incomplete glottic closure. Conclusion Vagal nerve sacrifice during resection of vagal schwannoma can be performed with normal postoperative swallowing function.
Sasaki, K.; Nadel, J.A.; Hahn, H.L.
We exposed two awake dogs with a chronic tracheostomy and the cervical vagus nerves exteriorized in skin loops to 1.0 ppm of ozone (O/sub 3/) for 2 h at intervals of 4 wk. We measured ventilatory variables before and after O/sub 3/ exposure during rest and exercise before and after vagal block. We compared the effects of vagal blockade, exercise, and O/sub 3/ on the primary determinants of breathing pattern (VT/TI, VT/TE, TI, and TE) in each of three conditions: base line (steady state), during hypercapnia, and after inhalation of 1% histamine. Under base-line conditions, O/sub 3/ increased respiratory rate and decreased tidal volume (VT) by shortening time of expiration (TE) and time of inspiration (TI) without affecting VT/TI, an indicator of the neural drive to breathing. During progressive hypercapnia, O/sub 3/ shortened TE and TI by effects both on tonic (nonvolume-related) and on phasic (volume-related) vagal inputs, and only the latter were prevented completely by cooling of the vagus nerves. Histamine-induced tachypnea was increased by O/sub 3/ and was totally blocked by cooling the vagus nerves. It was concluded that O/sub 3/ shortens the timing of respiration without increasing ventilatory drive, shortens TI and TE through vagal and nonvagal pathways, increases tonic nonvagal and phasic vagal inputs, and stimulates more than one vagal fiber type.
R Kyle Palmer
Full Text Available Taste quality and palatability are two of the most important properties measured in the evaluation of taste stimuli. Human panels can report both aspects, but are of limited experimental flexibility and throughput capacity. Relatively efficient animal models for taste evaluation have been developed, but each of them is designed to measure either taste quality or palatability as independent experimental endpoints. We present here a new apparatus and method for high throughput quantification of both taste quality and palatability using rats in an operant taste discrimination paradigm. Cohorts of four rats were trained in a modified operant chamber to sample taste stimuli by licking solutions from a 96-well plate that moved in a randomized pattern beneath the chamber floor. As a rat's tongue entered the well it disrupted a laser beam projecting across the top of the 96-well plate, consequently producing two retractable levers that operated a pellet dispenser. The taste of sucrose was associated with food reinforcement by presses on a sucrose-designated lever, whereas the taste of water and other basic tastes were associated with the alternative lever. Each disruption of the laser was counted as a lick. Using this procedure, rats were trained to discriminate 100 mM sucrose from water, quinine, citric acid, and NaCl with 90-100% accuracy. Palatability was determined by the number of licks per trial and, due to intermediate rates of licking for water, was quantifiable along the entire spectrum of appetitiveness to aversiveness. All 96 samples were evaluated within 90 minute test sessions with no evidence of desensitization or fatigue. The technology is capable of generating multiple concentration-response functions within a single session, is suitable for in vivo primary screening of tastant libraries, and potentially can be used to evaluate stimuli for any taste system.
Bloomquist, Ryan F; Parnell, Nicholas F; Phillips, Kristine A; Fowler, Teresa E; Yu, Tian Y; Sharpe, Paul T; Streelman, J Todd
Teeth and taste buds are iteratively patterned structures that line the oro-pharynx of vertebrates. Biologists do not fully understand how teeth and taste buds develop from undifferentiated epithelium or how variation in organ density is regulated. These organs are typically studied independently because of their separate anatomical location in mammals: teeth on the jaw margin and taste buds on the tongue. However, in many aquatic animals like bony fishes, teeth and taste buds are colocalized one next to the other. Using genetic mapping in cichlid fishes, we identified shared loci controlling a positive correlation between tooth and taste bud densities. Genome intervals contained candidate genes expressed in tooth and taste bud fields. sfrp5 and bmper, notable for roles in Wingless (Wnt) and bone morphogenetic protein (BMP) signaling, were differentially expressed across cichlid species with divergent tooth and taste bud density, and were expressed in the development of both organs in mice. Synexpression analysis and chemical manipulation of Wnt, BMP, and Hedgehog (Hh) pathways suggest that a common cichlid oral lamina is competent to form teeth or taste buds. Wnt signaling couples tooth and taste bud density and BMP and Hh mediate distinct organ identity. Synthesizing data from fish and mouse, we suggest that the Wnt-BMP-Hh regulatory hierarchy that configures teeth and taste buds on mammalian jaws and tongues may be an evolutionary remnant inherited from ancestors wherein these organs were copatterned from common epithelium.
Jyotaki, Masafumi; Sanematsu, Keisuke; Shigemura, Noriatsu; Yoshida, Ryusuke; Ninomiya, Yuzo
Leptin is an important hormone that regulates food intake and energy homeostasis by acting on central and peripheral targets. In the gustatory system, leptin is known to selectively suppress sweet responses by inhibiting the activation of sweet sensitive taste cells. Sweet taste receptor (T1R2+T1R3) is also expressed in gut enteroendocrine cells and contributes to nutrient sensing, hormone release and glucose absorption. Because of the similarities in expression patterns between enteroendocrine and taste receptor cells, we hypothesized that they may also share similar mechanisms used to modify/regulate the sweet responsiveness of these cells by leptin. Here, we used mouse enteroendocrine cell line STC-1 and examined potential effect of leptin on Ca(2+) responses of STC-1 cells to various taste compounds. Ca(2+) responses to sweet compounds in STC-1 cells were suppressed by a rodent T1R3 inhibitor gurmarin, suggesting the involvement of T1R3-dependent receptors in detection of sweet compounds. Responses to sweet substances were suppressed by ⩾1ng/ml leptin without affecting responses to bitter, umami and salty compounds. This effect was inhibited by a leptin antagonist (mutant L39A/D40A/F41A) and by ATP gated K(+) (KATP) channel closer glibenclamide, suggesting that leptin affects sweet taste responses of enteroendocrine cells via activation of leptin receptor and KATP channel expressed in these cells. Moreover, leptin selectively inhibited sweet-induced but not bitter-induced glucagon-like peptide-1 (GLP-1) secretion from STC-1 cells. These results suggest that leptin modulates sweet taste responses of enteroendocrine cells to regulate nutrient sensing, hormone release and glucose absorption in the gut. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.
Boris, Gorzalka; Hanson, Laura; Harrington, J
Two experiments were designed to elucidate the involvement of the hypothalamic-pituitary-adrenal axis and the 5-hydroxytryptamine (5-HT) system in the acquisition of lithium chloride-conditioned taste aversion. In Experiment 1, rats were administered either vehicle or 50 mg/kg nefazodone daily...... for 4 weeks. Rats were treated with 22 mg/kg of lithium chloride in order to produce conditioned taste aversion to a sucrose solution. Three days later, nefazodone completely blocked the lithium chloride-conditioned taste aversion. In Experiment 2, the effects of chronic corticosterone administration...... on lithium chloride-conditioned taste aversion were investigated. Twenty male rats received either corticosterone at a dose of (50 mg/kg) or vehicle injections over a period of 14 consecutive days. Lithium chloride-conditioned taste aversion was potentiated in rats treated with corticosterone. Additionally...
Christensen, Mette K; Lykkegaard, Eva; Lund, Ole; O'Neill, Lotte D
Recent years have seen leading medical educationalists repeatedly call for a paradigm shift in the way we view, value and use subjectivity in assessment. The argument is that subjective expert raters generally bring desired quality, not just noise, to performance evaluations. While several reviews document the psychometric qualities of the Multiple Mini-Interview (MMI), we currently lack qualitative studies examining what we can learn from MMI raters' subjectivity. The present qualitative study therefore investigates rater subjectivity or taste in MMI selection interview. Taste (Bourdieu 1984) is a practical sense, which makes it possible at a pre-reflective level to apply 'invisible' or 'tacit' categories of perception for distinguishing between good and bad. The study draws on data from explorative in-depth interviews with 12 purposefully selected MMI raters. We find that MMI raters spontaneously applied subjective criteria-their taste-enabling them to assess the candidates' interpersonal attributes and to predict the candidates' potential. In addition, MMI raters seemed to share a taste for certain qualities in the candidates (e.g. reflectivity, resilience, empathy, contact, alikeness, 'the good colleague'); hence, taste may be the result of an ongoing enculturation in medical education and healthcare systems. This study suggests that taste is an inevitable condition in the assessment of students' performance. The MMI set-up should therefore make room for MMI raters' taste and their connoisseurship, i.e. their ability to taste, to improve the quality of their assessment of medical school candidates.
Yu-Chieh David Chen
Full Text Available Summary: The Drosophila pharyngeal taste organs are poorly characterized despite their location at important sites for monitoring food quality. Functional analysis of pharyngeal neurons has been hindered by the paucity of molecular tools to manipulate them, as well as their relative inaccessibility for neurophysiological investigations. Here, we generate receptor-to-neuron maps of all three pharyngeal taste organs by performing a comprehensive chemoreceptor-GAL4/LexA expression analysis. The organization of pharyngeal neurons reveals similarities and distinctions in receptor repertoires and neuronal groupings compared to external taste neurons. We validate the mapping results by pinpointing a single pharyngeal neuron required for feeding avoidance of L-canavanine. Inducible activation of pharyngeal taste neurons reveals functional differences between external and internal taste neurons and functional subdivision within pharyngeal sweet neurons. Our results provide roadmaps of pharyngeal taste organs in an insect model system for probing the role of these understudied neurons in controlling feeding behaviors. : Chen and Dahanukar carry out a large-scale, systematic analysis to understand the molecular organization of pharyngeal taste neurons. Taking advantage of the molecular genetic toolkit that arises from this map, they use genetic dissection strategies to probe the functional roles of selected pharyngeal neurons in food choice. Keywords: Drosophila, taste, pharynx, chemosensory receptors, gustatory receptors, ionotropic receptors, feeding
Lemon, Christian H
This mini-review discusses some of the parallels between rodent neurophysiological and human psychophysical data concerning temperature effects on sweet taste. "Sweet" is an innately rewarding taste sensation that is associated in part with foods that contain calories in the form of sugars. Humans and other mammals can show unconditioned preference for select sweet stimuli. Such preference is poised to influence diet selection and, in turn, nutritional status, which underscores the importance of delineating the physiological mechanisms for sweet taste with respect to their influence on human health. Advances in our knowledge of the biology of sweet taste in humans have arisen in part through studies on mechanisms of gustatory processing in rodent models. Along this line, recent work has revealed there are operational parallels in neural systems for sweet taste between mice and humans, as indexed by similarities in the effects of temperature on central neurophysiological and psychophysical responses to sucrose in these species. Such association strengthens the postulate that rodents can serve as effective models of particular mechanisms of appetitive taste processing. Data supporting this link are discussed here, as are rodent and human data that shed light on relationships between mechanisms for sweet taste and ingestive disorders, such as alcohol abuse. Rodent models have utility for understanding mechanisms of taste processing that may pertain to human flavor perception. Importantly, there are limitations to generalizing data from rodents, albeit parallels across species do exist.
Colomb, Julien; Grillenzoni, Nicola; Ramaekers, Ariane; Stocker, Reinhard F
A simple nervous system combined with stereotypic behavioral responses to tastants, together with powerful genetic and molecular tools, have turned Drosophila larvae into a very promising model for studying gustatory coding. Using the Gal4/UAS system and confocal microscopy for visualizing gustatory afferents, we provide a description of the primary taste center in the larval central nervous system. Essentially, gustatory receptor neurons target different areas of the subesophageal ganglion (SOG), depending on their segmental and sensory organ origin. We define two major and two smaller subregions in the SOG. One of the major areas is a target of pharyngeal sensilla, the other one receives inputs from both internal and external sensilla. In addition to such spatial organization of the taste center, circumstantial evidence suggests a subtle functional organization: aversive and attractive stimuli might be processed in the anterior and posterior part of the SOG, respectively. Our results also suggest less coexpression of gustatory receptors than proposed in prior studies. Finally, projections of putative second-order taste neurons seem to cover large areas of the SOG. These neurons may thus receive multiple gustatory inputs. This suggests broad sensitivity of secondary taste neurons, reminiscent of the situation in mammals.
Chang, Rui B; Strochlic, David E; Williams, Erika K; Umans, Benjamin D; Liberles, Stephen D
Breathing is essential for survival and under precise neural control. The vagus nerve is a major conduit between lung and brain required for normal respiration. Here, we identify two populations of mouse vagus nerve afferents (P2ry1, Npy2r), each a few hundred neurons, that exert powerful and opposing effects on breathing. Genetically guided anatomical mapping revealed that these neurons densely innervate the lung and send long-range projections to different brainstem targets. Npy2r neurons are largely slow-conducting C fibers, while P2ry1 neurons are largely fast-conducting A fibers that contact pulmonary endocrine cells (neuroepithelial bodies). Optogenetic stimulation of P2ry1 neurons acutely silences respiration, trapping animals in exhalation, while stimulating Npy2r neurons causes rapid, shallow breathing. Activating P2ry1 neurons did not impact heart rate or gastric pressure, other autonomic functions under vagal control. Thus, the vagus nerve contains intermingled sensory neurons constituting genetically definable labeled lines with different anatomical connections and physiological roles. Copyright © 2015 Elsevier Inc. All rights reserved.
P.S Teo; Prof. dr Olaf van Kooten; M Mars; Vera van Stokkom; M Stieger; C de Graaf
Taste is a main driver in preferences and food choices. Humans are predispositioned to prefer sweet and salty tastes and reject bitter and sour tastes, therefore bitter taste is often thought to cause the rejection of vegetables by children. In our study we investigated the taste and fattiness
A. Visser; R. van Weissenbruch; A. Vissink; A. van Nieuw Amerongen; F.K.L. Spijkervet; Dr Harriët Jager-Wittenaar
Taste and smell perception are closely related. The taste perception is performed by taste buds which can distinguish salt, sour, sweet, bitter, and umami. Moreover, 2,000-4,000 smells can be recognized. Many taste disorders are in fact smell disorders. Saliva affects taste perception because it
Tobitani, Kensuke; Kato, Kunihito; Yamamoto, Kazuhiko
In this study, we focused on the basic taste stimulation for the analysis of real facial expressions. We considered that the expressions caused by taste stimulation were unaffected by individuality or emotion, that is, such expressions were involuntary. We analyzed the movement of facial muscles by taste stimulation and compared real expressions with artificial expressions. From the result, we identified an obvious difference between real and artificial expressions. Thus, our method would be a new approach for facial expression recognition.
Gustatory and olfactory senses receive chemical substances at the biological membranes of taste and olfactory cells, respectively. The present review article describes electronic tongue (taste sensor) and electronic nose (odor sensor) developed based on biomimetic technology. A taste sensor is now commercially sold and utilized in pharmaceutical and food companies across the world. An electronic nose with high sensitivity was also commercialized in Japan. These sensors provide novel methods for analyzing chemical substances instead of using conventional tools.
Winkler, S; Garg, A K; Mekayarajjananonth, T; Bakaeen, L G; Khan, E
Geriatric patients have a number of dental care problems that younger patients do not encounter. The oral changes associated with aging can have a significant effect on the efficacy of dental treatment. The authors reviewed studies dealing with the causes of depressed sense of taste and smell; the causes included aging, disease, medications and dental problems. Based on their findings, the authors described the location and anatomy of taste buds and receptor cells for smell and explored appetite, saliva, food seasonings, nutrition and dietary recommendations. They also discussed the relationship of smoking and tongue cleaning to taste sensations. The authors found that considerable differences exist between elderly people and young people in regards to sensory perception and pleasantness of food flavors. Salt and bitter taste acuity declines with age, but sweet and sour perceptivity does not. Olfactory acuity also declines with age. The authors found that most of the studies reviewed suggested that the sense of smell is more impaired by aging compared with the sense of taste. Smoking diminishes the taste of food and makes flavorful foods taste flat, while tongue brushing can increase taste sensation for geriatric patients. Food can become tasteless and unappetizing for geriatric patients as the result of declining taste and smell perception. Geriatric patients should be encouraged to add seasonings to their food instead of relying on excessive consumption of salt and sugar to give their food flavor. Adequate nutrition, tongue cleaning and smoking cessation are recommended for geriatric dental patients.
Li, Xiaodong; Staszewski, Lena; Xu, Hong; Durick, Kyle; Zoller, Mark; Adler, Elliot
The three members of the T1R class of taste-specific G protein-coupled receptors have been hypothesized to function in combination as heterodimeric sweet taste receptors. Here we show that human T1R2/T1R3 recognizes diverse natural and synthetic sweeteners. In contrast, human T1R1/T1R3 responds to the umami taste stimulus l-glutamate, and this response is enhanced by 5′-ribonucleotides, a hallmark of umami taste. The ligand specificities of rat T1R2/T1R3 and T1R1/T1R3 correspond to those of t...
Vance, Katie M; Rogers, Richard C; Hermann, Gerlinda E
Previous behavioral studies have demonstrated that presynaptic N-methyl-d-aspartate (NMDA) receptors expressed on vagal afferent terminals are involved in food intake and satiety. Therefore, using in vitro live cell calcium imaging of prelabeled rat hindbrain slices, we characterized which NMDA receptor GluN2 subunits may regulate vagal afferent activity. The nonselective NMDA receptor antagonist d,l-2-amino-5-phosphonopentanoic acid (d,l-AP5) significantly inhibited vagal terminal calcium influx, while the excitatory amino acid reuptake inhibitor d,l-threo-β-benzyloxyaspartic acid (TBOA), significantly increased terminal calcium levels following pharmacological stimulation with ATP. Subunit-specific NMDA receptor antagonists and potentiators were used to identify which GluN2 subunits mediate the NMDA receptor response on the vagal afferent terminals. The GluN2B-selective antagonist, ifenprodil, selectively reduced vagal calcium influx with stimulation compared to the time control. The GluN2A-selective antagonist, 3-chloro-4-fluoro-N-[4-[[2-(phenylcarbonyl)hydrazino]carbonyl] benzyl]benzenesulfonamide (TCN 201) produced smaller but not statistically significant effects. Furthermore, the GluN2A/B-selective potentiator (pregnenolone sulfate) and the GluN2C/D-selective potentiator [(3-chlorophenyl)(6,7-dimethoxy-1-((4-methoxyphenoxy)methyl)-3,4-dihydroisoquinolin-2(1H)-yl)methanone; (CIQ)] enhanced vagal afferent calcium influx during stimulation. These data suggest that presynaptic NMDA receptors with GluN2B, GluN2C, and GluN2D subunits may predominantly control vagal afferent excitability in the nucleus of the solitary tract. Copyright © 2014 Elsevier B.V. All rights reserved.
Jones, Peter; Guillaud, Laurent; Desbois, Christophe; Benoist, Jean-Francois; Combrisson, Helene; Dauger, Stephane; Peters, Mark J
The haemodynamic response to critical care intubation is influenced by the use of sedation and relaxant drugs and the activation of the vagal reflex. It has been hypothesized that different disease states may have a contrasting effect on the cardiovascular response to vagal stimulation. Our objective was to determine whether the blood pressure response to vagal stimulation was modified by endotoxaemia or hypovolaemia. New Zealand White rabbits were anaesthetised with urethane before tracheotomy. The exposed left Vagus nerve of randomised groups of control (n = 11), endotoxin (n = 11, 1 mg/kg), hypovolaemia 40% (n = 8) and hypovolaemia 20% (n = 8) rabbits were subjected to 10 Hz pulsed electrical stimulations of 25 s duration every 15 min. Haemodynamic parameters were recorded from a catheter in the right carotid artery connected to an iWorx monitor. Serum catecholamines were measured every 30 min using reverse-phase ion-pairing liquid chromatography. The change in blood pressure after vagal stimulation was compared to controls for one hour after the first death in the experimental groups. 29% of the rabbits died in the hypovolaemia 40% group and 27% in the endotoxin group. One rabbit died in the hypovolaemia 40% group before vagal stimulation and was excluded. Following electrical stimulation of the Vagus nerve there was a fall in blood pressure in control rabbits. Blood pressure was conserved in the hypovolaemic rabbits compared to controls (pblood pressure to decrease more than the controls. Serum catecholamines were significantly raised in both the hypovolaemic and endotoxaemic rabbits. Pathology may contribute to modifications in blood pressure when vagal activation occurs. Patients who are either already vasoconstricted, or not vasoplegic, may be less at risk from intubation-related vagally mediated reductions in blood pressure than those with vasodilatory pathologies.
Full Text Available PURPOSE: The haemodynamic response to critical care intubation is influenced by the use of sedation and relaxant drugs and the activation of the vagal reflex. It has been hypothesized that different disease states may have a contrasting effect on the cardiovascular response to vagal stimulation. Our objective was to determine whether the blood pressure response to vagal stimulation was modified by endotoxaemia or hypovolaemia. METHODS: New Zealand White rabbits were anaesthetised with urethane before tracheotomy. The exposed left Vagus nerve of randomised groups of control (n = 11, endotoxin (n = 11, 1 mg/kg, hypovolaemia 40% (n = 8 and hypovolaemia 20% (n = 8 rabbits were subjected to 10 Hz pulsed electrical stimulations of 25 s duration every 15 min. Haemodynamic parameters were recorded from a catheter in the right carotid artery connected to an iWorx monitor. Serum catecholamines were measured every 30 min using reverse-phase ion-pairing liquid chromatography. The change in blood pressure after vagal stimulation was compared to controls for one hour after the first death in the experimental groups. RESULTS: 29% of the rabbits died in the hypovolaemia 40% group and 27% in the endotoxin group. One rabbit died in the hypovolaemia 40% group before vagal stimulation and was excluded. Following electrical stimulation of the Vagus nerve there was a fall in blood pressure in control rabbits. Blood pressure was conserved in the hypovolaemic rabbits compared to controls (p<0.01. For the endotoxaemic rabbits, there was a non-significant trend for the mean blood pressure to decrease more than the controls. Serum catecholamines were significantly raised in both the hypovolaemic and endotoxaemic rabbits. CONCLUSIONS: Pathology may contribute to modifications in blood pressure when vagal activation occurs. Patients who are either already vasoconstricted, or not vasoplegic, may be less at risk from intubation-related vagally mediated
Gautron, Laurent; Sakata, Ichiro; Udit, Swalpa; Zigman, Jeffrey M; Wood, John N; Elmquist, Joel K
Nav1.8 is a tetrodotoxin-resistant sodium channel present in large subsets of peripheral sensory neurons, including both spinal and vagal afferents. In spinal afferents, Nav1.8 plays a key role in signaling different types of pain. Little is known, however, about the exact identity and role of Nav1.8-expressing vagal neurons. Here we generated mice with restricted expression of tdTomato fluorescent protein in all Nav1.8-expressing afferent neurons. As a result, intense fluorescence was visible in the cell bodies, central relays, and sensory endings of these neurons, revealing the full extent of their innervation sites in thoracic and abdominal viscera. For instance, vagal and spinal Nav1.8-expressing endings were seen clearly within the gastrointestinal mucosa and myenteric plexus, respectively. In the gastrointestinal muscle wall, labeled endings included a small subset of vagal tension receptors but not any stretch receptors. We also examined the detailed innervation of key metabolic tissues such as liver and pancreas and evaluated the anatomical relationship of Nav1.8-expressing vagal afferents with select enteroendocrine cells (i.e., ghrelin, glucagon, GLP-1). Specifically, our data revealed the presence of Nav1.8-expressing vagal afferents in several metabolic tissues and varying degrees of proximity between Nav1.8-expressing mucosal afferents and enteroendocrine cells, including apparent neuroendocrine apposition. In summary, this study demonstrates the power and versatility of the Cre-LoxP technology to trace identified visceral afferents, and our data suggest a previously unrecognized role for Nav1.8-expressing vagal neurons in gastrointestinal functions. Copyright © 2011 Wiley-Liss, Inc.
Thunström, Linda; Nordström, Leif Jonas
This paper quantitatively analyzes the importance of taste versus health in food demand, as well as the effect on consumers’ experienced taste of the non-intrinsic value of healthy labels. Our analysis is based on taste experiments and Vickrey second price auctions on potato chips and bread. Our...
Full Text Available In response to taste stimulation, taste buds release ATP, which activates ionotropic ATP receptors (P2X2/P2X3 on taste nerves as well as metabotropic (P2Y purinergic receptors on taste bud cells. The action of the extracellular ATP is terminated by ectonucleotidases, ultimately generating adenosine, which itself can activate one or more G-protein coupled adenosine receptors: A1, A2A, A2B, and A3. Here we investigated the expression of adenosine receptors in mouse taste buds at both the nucleotide and protein expression levels. Of the adenosine receptors, only A2B receptor (A2BR is expressed specifically in taste epithelia. Further, A2BR is expressed abundantly only in a subset of taste bud cells of posterior (circumvallate, foliate, but not anterior (fungiform, palate taste fields in mice. Analysis of double-labeled tissue indicates that A2BR occurs on Type II taste bud cells that also express Gα14, which is present only in sweet-sensitive taste cells of the foliate and circumvallate papillae. Glossopharyngeal nerve recordings from A2BR knockout mice show significantly reduced responses to both sucrose and synthetic sweeteners, but normal responses to tastants representing other qualities. Thus, our study identified a novel regulator of sweet taste, the A2BR, which functions to potentiate sweet responses in posterior lingual taste fields.
Yang, Dan; Shultz, Nicole; Vandenbeuch, Aurelie; Ravid, Katya; Kinnamon, Sue C.; Finger, Thomas E.
In response to taste stimulation, taste buds release ATP, which activates ionotropic ATP receptors (P2X2/P2X3) on taste nerves as well as metabotropic (P2Y) purinergic receptors on taste bud cells. The action of the extracellular ATP is terminated by ectonucleotidases, ultimately generating adenosine, which itself can activate one or more G-protein coupled adenosine receptors: A1, A2A, A2B, and A3. Here we investigated the expression of adenosine receptors in mouse taste buds at both the nucleotide and protein expression levels. Of the adenosine receptors, only A2B receptor (A2BR) is expressed specifically in taste epithelia. Further, A2BR is expressed abundantly only in a subset of taste bud cells of posterior (circumvallate, foliate), but not anterior (fungiform, palate) taste fields in mice. Analysis of double-labeled tissue indicates that A2BR occurs on Type II taste bud cells that also express Gα14, which is present only in sweet-sensitive taste cells of the foliate and circumvallate papillae. Glossopharyngeal nerve recordings from A2BR knockout mice show significantly reduced responses to both sucrose and synthetic sweeteners, but normal responses to tastants representing other qualities. Thus, our study identified a novel regulator of sweet taste, the A2BR, which functions to potentiate sweet responses in posterior lingual taste fields. PMID:22253866
Anderson Catherine B
Full Text Available Abstract Background Glutamate has been proposed as a transmitter in the peripheral taste system in addition to its well-documented role as an umami taste stimulus. Evidence for a role as a transmitter includes the presence of ionotropic glutamate receptors in nerve fibers and taste cells, as well as the expression of the glutamate transporter GLAST in Type I taste cells. However, the source and targets of glutamate in lingual tissue are unclear. In the present study, we used molecular, physiological and immunohistochemical methods to investigate the origin of glutamate as well as the targeted receptors in taste buds. Results Using molecular and immunohistochemical techniques, we show that the vesicular transporters for glutamate, VGLUT 1 and 2, but not VGLUT3, are expressed in the nerve fibers surrounding taste buds but likely not in taste cells themselves. Further, we show that P2X2, a specific marker for gustatory but not trigeminal fibers, co-localizes with VGLUT2, suggesting the VGLUT-expressing nerve fibers are of gustatory origin. Calcium imaging indicates that GAD67-GFP Type III taste cells, but not T1R3-GFP Type II cells, respond to glutamate at concentrations expected for a glutamate transmitter, and further, that these responses are partially blocked by NBQX, a specific AMPA/Kainate receptor antagonist. RT-PCR and immunohistochemistry confirm the presence of the Kainate receptor GluR7 in Type III taste cells, suggesting it may be a target of glutamate released from gustatory nerve fibers. Conclusions Taken together, the results suggest that glutamate may be released from gustatory nerve fibers using a vesicular mechanism to modulate Type III taste cells via GluR7.
Full Text Available Taste perception plays an important role in regulating food preference, eating behavior and energy homeostasis. Taste perception is modulated by a variety of factors, including gastric hormones such as ghrelin. Ghrelin can regulate growth hormone release, food intake, adiposity, and energy metabolism. Octanoylation of ghrelin by ghrelin O-acyltransferase (GOAT is a specific post-translational modification which is essential for many biological activities of ghrelin. Ghrelin and GOAT are both widely expressed in many organs including the gustatory system. In the current study, overall metabolic profiles were assessed in wild-type (WT, ghrelin knockout (ghrelin(-/-, and GOAT knockout (GOAT(-/- mice. Ghrelin(-/- mice exhibited decreased food intake, increased plasma triglycerides and increased ketone bodies compared to WT mice while demonstrating WT-like body weight, fat composition and glucose control. In contrast GOAT(-/- mice exhibited reduced body weight, adiposity, resting glucose and insulin levels compared to WT mice. Brief access taste behavioral tests were performed to determine taste responsivity in WT, ghrelin(-/- and GOAT(-/- mice. Ghrelin and GOAT null mice possessed reduced lipid taste responsivity. Furthermore, we found that salty taste responsivity was attenuated in ghrelin(-/- mice, yet potentiated in GOAT(-/- mice compared to WT mice. Expression of the potential lipid taste regulators Cd36 and Gpr120 were reduced in the taste buds of ghrelin and GOAT null mice, while the salt-sensitive ENaC subunit was increased in GOAT(-/- mice compared with WT mice. The altered expression of Cd36, Gpr120 and ENaC may be responsible for the altered lipid and salt taste perception in ghrelin(-/- and GOAT(-/- mice. The data presented in the current study potentially implicates ghrelin signaling activity in the modulation of both lipid and salt taste modalities.
Daimon, Caitlin M.; Wang, Rui; Tschöp, Matthias H.; Sévigny, Jean; Martin, Bronwen; Maudsley, Stuart
Taste perception plays an important role in regulating food preference, eating behavior and energy homeostasis. Taste perception is modulated by a variety of factors, including gastric hormones such as ghrelin. Ghrelin can regulate growth hormone release, food intake, adiposity, and energy metabolism. Octanoylation of ghrelin by ghrelin O-acyltransferase (GOAT) is a specific post-translational modification which is essential for many biological activities of ghrelin. Ghrelin and GOAT are both widely expressed in many organs including the gustatory system. In the current study, overall metabolic profiles were assessed in wild-type (WT), ghrelin knockout (ghrelin−/−), and GOAT knockout (GOAT−/−) mice. Ghrelin−/− mice exhibited decreased food intake, increased plasma triglycerides and increased ketone bodies compared to WT mice while demonstrating WT-like body weight, fat composition and glucose control. In contrast GOAT−/− mice exhibited reduced body weight, adiposity, resting glucose and insulin levels compared to WT mice. Brief access taste behavioral tests were performed to determine taste responsivity in WT, ghrelin−/− and GOAT−/− mice. Ghrelin and GOAT null mice possessed reduced lipid taste responsivity. Furthermore, we found that salty taste responsivity was attenuated in ghrelin−/− mice, yet potentiated in GOAT−/− mice compared to WT mice. Expression of the potential lipid taste regulators Cd36 and Gpr120 were reduced in the taste buds of ghrelin and GOAT null mice, while the salt-sensitive ENaC subunit was increased in GOAT−/− mice compared with WT mice. The altered expression of Cd36, Gpr120 and ENaC may be responsible for the altered lipid and salt taste perception in ghrelin−/− and GOAT−/− mice. The data presented in the current study potentially implicates ghrelin signaling activity in the modulation of both lipid and salt taste modalities. PMID:24124572
Two experiments were conducted to study overshadowing of extinction in a conditioned taste aversion preparation. In both experiments, aversive conditioning with sucrose was followed by extinction treatment with either sucrose alone or in compound with another taste, citric acid. Experiment 1 employed a simultaneous compound extinction treatment…
McLaughlin, Katie A; Rith-Najarian, Leslie; Dirks, Melanie A; Sheridan, Margaret A
Vagal tone is a measure of cardiovascular function that facilitates adaptive responses to environmental challenge. Low vagal tone is associated with poor emotional and attentional regulation in children and has been conceptualized as a marker of sensitivity to stress. We investigated whether the associations of a wide range of psychosocial stressors with internalizing and externalizing psychopathology were magnified in adolescents with low vagal tone. Resting heart period data were collected from a diverse community sample of adolescents (ages 13-17; N = 168). Adolescents completed measures assessing internalizing and externalizing psychopathology and exposure to stressors occurring in family, peer, and community contexts. Respiratory sinus arrhythmia (RSA) was calculated from the interbeat interval time series. We estimated interactions between RSA and stress exposure in predicting internalizing and externalizing symptoms and evaluated whether interactions differed by gender. Exposure to psychosocial stressors was associated strongly with psychopathology. RSA was unrelated to internalizing or externalizing problems. Significant interactions were observed between RSA and child abuse, community violence, peer victimization, and traumatic events in predicting internalizing but not externalizing symptoms. Stressors were positively associated with internalizing symptoms in adolescents with low RSA but not in those with high RSA. Similar patterns were observed for anxiety and depression. These interactions were more consistently observed for male than female individuals. Low vagal tone is associated with internalizing psychopathology in adolescents exposed to high levels of stressors. Measurement of vagal tone in clinical settings might provide useful information about sensitivity to stress in child and adolescent clients.
Goldberg, David; Borojevic, Rajka; Anderson, Monique; Chen, Jason J; Gershon, Michael D; Ratcliffe, Elyanne M
The vagus nerve descends from the brain to the gut during fetal life to reach specific targets in the bowel wall. Vagal sensory axons have been shown to respond to the axon guidance molecule netrin and to its receptor, deleted in colorectal cancer (DCC). As there are regions of the gut wall into which vagal axons do and do not extend, it is likely that a combination of attractive and repellent cues are involved in how vagal axons reach specific targets. We tested the hypothesis that Slit/Robo chemorepulsion can contribute to the restriction of vagal sensory axons to specific targets in the gut wall. Transcripts encoding Robo1 and Robo2 were expressed in the nodose ganglia throughout development and mRNA encoding the Robo ligands Slit1, Slit2, and Slit3 were all found in the fetal and adult bowel. Slit2 protein was located in the outer gut mesenchyme in regions that partially overlap with the secretion of netrin-1. Neurites extending from explanted nodose ganglia were repelled by Slit2. These observations suggest that vagal sensory axons are responsive to Slit proteins and are thus repelled by Slits secreted in the gut wall and prevented from reaching inappropriate targets. Copyright © 2012 Wiley Periodicals, Inc.
De Lartigue, Guillaume; Dimaline, Rod; Varro, Andrea; Raybould, Helen; De la Serre, Claire Barbier; Dockray, Graham J
Cholecystokinin (CCK) acts on vagal afferent neurons to inhibit food intake and gastric emptying; it also increases expression of the neuropeptide cocaine- and amphetamine-regulated transcript (CART), but the significance of this is unknown. We investigated the role of CARTp in vagal afferent neurons. Release of CART peptide (CARTp) from cultured vagal afferent neurons was determined by enzyme-linked immunosorbent assay. Expression of receptors and neuropeptides in rat vagal afferent neurons in response to CARTp was studied using immunohistochemistry and luciferase promoter reporter constructs. Effects of CARTp and CCK were studied on food intake. CCK stimulated CARTp release from cultured nodose neurons. CARTp replicated the effect of CCK in stimulating expression of Y2R and of CART itself in these neurons in vivo and in vitro, but not in inhibiting cannabinoid-1, melanin-concentrating hormone, and melanin-concentrating hormone-1 receptor expression. Effects of CCK on Y2R and CART expression were reduced by CART small interfering RNA or brefeldin A. Exposure of rats to CARTp increased the inhibitory action of CCK on food intake after short-, but not long-duration, fasting. The actions of CCK in stimulating CART and Y2R expression in vagal afferent neurons and in inhibiting food intake are augmented by CARTp; CARTp is released by CCK from these neurons, indicating that it acts as an autocrine excitatory mediator. 2010 AGA Institute. Published by Elsevier Inc. All rights reserved.
McLaughlin, Katie A.; Rith-Najarian, Leslie; Dirks, Melanie A.; Sheridan, Margaret A.
Vagal tone is a measure of cardiovascular function that facilitates adaptive responses to environmental challenge. Low vagal tone is associated with poor emotional and attentional regulation in children and has been conceptualized as a marker of sensitivity to stress. We investigated whether the associations of a wide range of psychosocial stressors with internalizing and externalizing psychopathology were magnified in adolescents with low vagal tone. Resting heart period data were collected from a diverse community sample of adolescents (ages 13–17; N =168). Adolescents completed measures assessing internalizing and externalizing psychopathology and exposure to stressors occurring in family, peer, and community contexts. Respiratory sinus arrhythmia (RSA) was calculated from the interbeat interval time series. We estimated interactions between RSA and stress exposure in predicting internalizing and externalizing symptoms and evaluated whether interactions differed by gender. Exposure to psychosocial stressors was associated strongly with psychopathology. RSA was unrelated to internalizing or externalizing problems. Significant interactions were observed between RSA and child abuse, community violence, peer victimization, and traumatic events in predicting internalizing but not externalizing symptoms. Stressors were positively associated with internalizing symptoms in adolescents with low RSA but not in those with high RSA. Similar patterns were observed for anxiety and depression. These interactions were more consistently observed for male than female individuals. Low vagal tone is associated with internalizing psychopathology in adolescents exposed to high levels of stressors. Measurement of vagal tone in clinical settings might provide useful information about sensitivity to stress in child and adolescent clients. PMID:24156380
Passi, Rohit; Doheny, Kim K; Gordin, Yuri; Hinssen, Hans; Palmer, Charles
Low vagal tone (VT) is a marker of vulnerability to stress and the risk of developing necrotizing enterocolitis in preterm infants. Electric fields produced by equipment in the neonatal intensive care unit (NICU) induce an electric potential measurable on the skin in reference to ground. An electrical connection to ground reduces the skin potential and improves VT in adults. We aimed to measure the electric field strengths in the NICU environment and to determine if connecting an infant to electrical ground would reduce the skin potential and improve VT. We also wished to determine if the skin potential correlated with VT. Environmental magnetic flux density (MFD) was measured in and around incubators. Electrical grounding (EG) was achieved with a patch electrode and wire that extended to a ground outlet. We measured the skin potential in 26 infants and heart rate variability in 20 infants before, during, and after grounding. VT was represented by the high-frequency power of heart rate variability. The background MFD in the NICU was below 0.5 mG, but it ranged between 1.5 and 12.7 mG in the closed incubator. A 60-Hz oscillating potential was recorded on the skin of all infants. With EG, the skin voltage dropped by about 95%. Pre-grounding VT was inversely correlated with the skin potential. VT increased by 67% with EG. After grounding, the VT fell to the pre-grounding level. The electrical environment affects autonomic balance. EG improves VT and may improve resilience to stress and lower the risk of neonatal morbidity in preterm infants. © 2017 S. Karger AG, Basel.
Boesveldt, Sanne; de Graaf, Kees
Food choice and food intake are guided by both sensory and metabolic processes. The senses of taste and smell play a key role in the sensory effects on choice and intake. This article provides a comprehensive overview of, and will argue for, the differential role of smell and taste for eating behavior by focusing on appetite, choice, intake, and satiation. The sense of smell mainly plays a priming role in eating behavior. It has been demonstrated that (orthonasal) odor exposure induces appetite specifically for the cued food. However, the influence of odors on food choice and intake is less clear, and may also depend on awareness or intensity of the odors, or personality traits of the participants. Taste on the other hand, has a clear role as a (macro)nutrient sensing system, during consumption. Together with texture, taste is responsible for eating rate, and thus in determining the oral exposure duration of food in the mouth, thereby contributing to satiation. Results from these experimental studies should be taken to real-life situations, to assess longer-term effects on energy intake. With this knowledge, it will be possible to steer people's eating behavior, as well as food product development, toward a less obesogenic society.
DeSimone, John A; Lyall, Vijay
.... The sodium-specific salt taste receptor is the epithelial sodium channel whereas a nonspecific salt taste receptor is a taste variant of the vanilloid receptor-1 nonselective cation channel, TRPV1...
Ross-Harrington, Melinda; Kincaid, G. David
One of twelve water treatment technology units, this student manual on taste, odor, and color provides instructional materials for three competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: taste and odor determination, control of…
Roper, Stephen D
Taste buds are peripheral chemosensory organs situated in the oral cavity. Each taste bud consists of a community of 50-100 cells that interact synaptically during gustatory stimulation. At least three distinct cell types are found in mammalian taste buds - Type I cells, Receptor (Type II) cells, and Presynaptic (Type III) cells. Type I cells appear to be glial-like cells. Receptor cells express G protein-coupled taste receptors for sweet, bitter, or umami compounds. Presynaptic cells transduce acid stimuli (sour taste). Cells that sense salt (NaCl) taste have not yet been confidently identified in terms of these cell types. During gustatory stimulation, taste bud cells secrete synaptic, autocrine, and paracrine transmitters. These transmitters include ATP, acetylcholine (ACh), serotonin (5-HT), norepinephrine (NE), and GABA. Glutamate is an efferent transmitter that stimulates Presynaptic cells to release 5-HT. This chapter discusses these transmitters, which cells release them, the postsynaptic targets for the transmitters, and how cell-cell communication shapes taste bud signaling via these transmitters. Copyright © 2012 Elsevier Ltd. All rights reserved.
Patients with cancer often experience changes in taste and smell perception during chemotherapy. The aim of this dissertation was to investigate taste and smell changes and short- and long-term effects of chemotherapy in a homogeneous population of testicular cancer patients treated with
In the industrialized countries children have many foods to choose from, both healthy and unhealthy products, these choices mainly depend on children's taste preferences. The present thesis focused on preferences for sweet and sour taste of young children (4- to 12-years of age) living in the US and
no equilibrium in which the firm always exerts high effort. However, when consumers learn about their own tastes, such an equilibrium can exist. Consumer learning about tastes therefore is an alternative to reputational concerns that produces stable incentives. We discuss the implications of this mechanism...
Chan, K.Q.; Tong, E.M.; Tan, D.H.; Koh, A.H.
Metaphorical expressions linking love and jealousy to sweet, sour, and bitter tastes are common in normal language use and suggest that these emotions may influence perceptual taste judgments. Hence, we investigated whether the phenomenological experiences of love and jealousy are embodied in the
Full Text Available The morphological changes that occur in the taste buds after denervation are not well understood in rats, especially in the contralateral tongue epithelium. In this study, we investigated the time course of morphological changes in the taste buds following unilateral nerve transection. The role of the trigeminal component of the lingual nerve in maintaining the structural integrity of the taste buds was also examined. Twenty-four Sprague-Dawley rats were randomly divided into three groups: control, unilateral chorda tympani nerve transection and unilateral chorda tympani nerve transection + lingual nerve transection. Rats were allowed up to 42 days of recovery before being euthanized. The taste buds were visualized using a cytokeratin 8 antibody. Taste bud counts, volumes and taste receptor cell numbers were quantified and compared among groups. No significant difference was detected between the chorda tympani nerve transection and chorda tympani nerve transection + lingual nerve transection groups. Taste bud counts, volumes and taste receptor cell numbers on the ipsilateral side all decreased significantly compared with control. On the contralateral side, the number of taste buds remained unchanged over time, but they were larger, and taste receptor cells were more numerous postoperatively. There was no evidence for a role of the trigeminal branch of the lingual nerve in maintaining the structural integrity of the anterior taste buds.
Cai, Huan; Daimon, Caitlin M; Cong, Wei-Na; Wang, Rui; Chirdon, Patrick; de Cabo, Rafael; Sévigny, Jean; Maudsley, Stuart; Martin, Bronwen
Calorie restriction (CR) is a lifestyle intervention employed to reduce body weight and improve metabolic functions primarily via reduction of ingested carbohydrates and fats. Taste perception is highly related to functional metabolic status and body adiposity. We have previously shown that sweet taste perception diminishes with age; however, relatively little is known about the effects of various lengths of CR upon taste cell morphology and function. We investigated the effects of CR on taste bud morphology and expression of sweet taste-related modulators in 5-, 17-, and 30-month-old rats. In ad libitum (AL) and CR rats, we consistently found the following parameters altered significantly with advancing age: reduction of taste bud size and taste cell numbers per taste bud and reduced expression of sonic hedgehog, type 1 taste receptor 3 (T1r3), α-gustducin, and glucagon-like peptide-1 (GLP-1). In the oldest rats, CR affected a significant reduction of tongue T1r3, GLP-1, and α-gustducin expression compared with age-matched AL rats. Leptin receptor immunopositive cells were elevated in 17- and 30-month-old CR rats compared with age-matched AL rats. These alterations of sweet taste-related modulators, specifically during advanced aging, suggest that sweet taste perception may be altered in response to different lengths of CR.
Li, Hong; Liu, Fang
The contributions of free hydrogen ions, undissociated hydrogen ions in protonated acid species, and anionic acid species to sour taste were studied through sensory experiments. According to tasting results, it can be inferred that the basic substance producing a sour taste is the hydrogen ion, including free hydrogen ions and undissociated hydrogen ions. The intensity of a sour taste is determined by the total concentration of free hydrogen ions and undissociated hydrogen ions. The anionic acid species (without hydrogen ions) does not produce a sour taste but can intensify or weaken the intensity of a sour taste. It seems that hydroxyl or conjugated groups in anionic acid species can intensify the sour taste produced by hydrogen ions. The following strategy to reduce the sensory sourness is advanced: not only reduce free hydrogen ions, namely elevate pH value, but also reduce the undissociated hydrogen ions contained in protonated acid species. Copyright © 2015 Elsevier Ltd. All rights reserved.
Kim, Han-Joon; Lee, Dong-Ha; Cho, Joong-Yang; Cho, Yong-Jin; Hong, Keun-Sik
In the cerebellopontine angle cistern, the nervus intermedius (NI) runs close to the motor division of the facial nerve (FN). A vascular loop compressing the FN in patients with hemifacial spasm (HFS) can thus also affect the NI. However, to our knowledge, taste has not been investigated in patients with HFS. In this pilot study, we assessed the sense of taste quantitatively in 10 female patients with HFS using filter paper strips impregnated with four taste qualities (sweet, sour, salty, and bitter) at four concentrations. The taste score did not differ between the ipsilateral and contralateral sides. The taste score for salty on the ipsilateral side increased with disease duration. Our findings suggest that a vascular loop compressing the FN does not affect the function of the NI. Further studies with greater numbers of patients are needed to confirm our results.
Lee, Allen A.; Owyang, Chung
Sweet taste receptors are composed of a heterodimer of taste 1 receptor member 2 (T1R2) and taste 1 receptor member 3 (T1R3). Accumulating evidence shows that sweet taste receptors are ubiquitous throughout the body, including in the gastrointestinal tract as well as the hypothalamus. These sweet taste receptors are heavily involved in nutrient sensing, monitoring changes in energy stores, and triggering metabolic and behavioral responses to maintain energy balance. Not surprisingly, these pathways are heavily regulated by external and internal factors. Dysfunction in one or more of these pathways may be important in the pathogenesis of common diseases, such as obesity and type 2 diabetes mellitus. PMID:28672790
Fletcher, Anne C.; Buehler, Cheryl; Buchanan, Christy M.; Weymouth, Bridget B.
Grounded in a dual-risk, biosocial perspective of developmental psychopathology, this study examined the role of higher vagal suppression in providing young adolescents protection from four parenting stressors. It was expected that lower vagal suppression would increase youth vulnerability to the deleterious effects of these parenting stressors. Depressive symptoms were examined as a central marker of socioemotional difficulties during early adolescence. The four parenting stressors examined were interparental hostility, maternal use of harsh discipline, maternal inconsistent discipline, and maternal psychological control. Participants were 68 young adolescents (Grade 6) and their mothers. Greater vagal suppression provided protection (i.e., lower depressive symptoms) from interparental hostility, harsh discipline, and maternal psychological control for boys but not for girls. PMID:27979628
Green, Barry G; Alvarado, Cynthia; Andrew, Kendra; Nachtigal, Danielle
The effect of temperature on umami taste has not been previously studied in humans. Reported here are 3 experiments in which umami taste was measured for monopotassium glutamate (MPG) and monosodium glutamate (MSG) at solution temperatures between 10 and 37 °C. Experiment 1 showed that for subjects sensitive to MPG on the tongue tip, 1) cooling reduced umami intensity whether sampled with the tongue tip or in the whole mouth, but 2) had no effect on the rate of umami adaptation on the tongue tip. Experiment 2 showed that temperature had similar effects on the umami taste of MSG and MPG on the tongue tip but not in the whole mouth, and that contrary to umami taste, cooling to 10 °C increased rather than decreased the salty taste of both stimuli. Experiment 3 was designed to investigate the contribution of the hT1R1-hT1R3 glutamate receptor to the cooling effect on umami taste by using the T1R3 inhibitor lactisole. However, lactisole failed to block the umami taste of MPG at any temperature, which supports prior evidence that lactisole does not block umami taste for all ligands of the hT1R1-hT1R3 receptor. We conclude that temperature can affect sensitivity to the umami and salty tastes of glutamates, but in opposite directions, and that the magnitude of these effects can vary across stimuli and modes of tasting (i.e., whole mouth vs. tongue tip exposures). © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: firstname.lastname@example.org.
Ogawa, T; Annear, M J; Ikebe, K; Maeda, Y
The sense of taste is important as it allows for assessment of nutritional value, safety and quality of foods as well as for food enjoyment and quality of life. Several factors are suggested to be associated with taste sensitivity, and higher prevalence of taste disorder has been reported among older adults. This review focused on the reported causes and correlates of taste decline in older adults, with the aim to consolidating existing evidence and identifying gaps and limitations. Using a scoping review methodology, we sought relevant literature from the last 20 years. Search terms included taste, gustatory sense, older adults and geriatric. Considered research was limited to reports that involved research participants over 60 years old, papers written in English, and manuscripts published after 1995. We have consolidated available evidences on the influences on taste-related sensations among international cohorts of older adults. Influences can be reflected under the topics of physiological changes in the sensory organs, physiological and behavioural variables related to taste sensation. This review identified three areas of historic and current research endeavour related to studies of taste sensation in older subjects: physiological changes in the sensory organs, factors related to the ageing of the individual and behavioural variables affecting taste-related sensation. Key limitations and gaps in the current literature include notable lack of consideration of potential confounding, mediating and moderating effects, while future research is indicated in the areas of measuring the quality of health and life. As global population ageing accelerates in the coming decades, maintaining taste sensations and sensitivity in older adults will be a key measure to ensuring quality of health and life. © 2017 John Wiley & Sons Ltd.
Morisawa, Masayuki; Kawai, Masahisa; Muto, Shinzo
In order to develop a simple system for sensing taste substances, an optical method using polymer/lipid films doped with a voltage-sensitive dye and plastic optical fibers (POFs) has been studied experimentally. The several kinds of polymer/lipid blended membranes doped with rhodamine-B dye with a long hydrocarbon chain were used after transferring on to the glass substrate glued on the end surface of POF. Its fluorescence intensity around 600 nm showed different patterns for the taste substance solutions such as bitter, salty and "umami". These results and a principal component analysis gave the possibility of an optical fiber taste substance sensor.
Vaga, Airi, 1940-
President Toomas Hendrik Ilves annetas iseseisvuspäeva puhul USA I praostkonna praostile Thomas Vagale Valgetähe IV klassi teenetemärgi. Teenetemärgi andis Thomas Vagale üle Eesti Vabariigi peakonsul Jaanus Kirikmäe
Crowley, Olga V.; McKinley, Paula S.; Burg, Matthew M.; Schwartz, Joseph E.; Ryff, Carol D.; Weinstein, Maxine; Seeman, Teresa E.; Sloan, Richard P.
The present study tested the hypothesis that the change in state negative affect (measured as perceived stress) after cognitive challenge moderates the relationship of trait anxiety and anger to vagal recovery from that challenge. Cardiac vagal control (assessed using heart rate variability) and respiratory rate were measured in a sample of 905 participants from the Midlife in the United States Study. Cognitive challenges consisted of computerized mental arithmetic and Stroop color-word matching tasks. Multiple regression analyses controlling for the effects of the demographic, lifestyle, and medical factors influencing cardiac vagal control showed a significant moderating effect of change in perceived stress on the relationship of trait anxiety to vagal recovery from cognitive challenges (Beta = .253, p= .013). After adjustment for respiratory rate, this effect became marginally significant (Beta = .177, p= .037). In contrast, for the relationship of trait anger to vagal recovery, this effect was not significant either before (Beta = .141, p=.257) or after (Beta = .186, p=.072) adjusting for respiratory rate. Secondary analyses revealed that among the individuals with higher levels of trait anxiety, greater reductions in perceived stress were associated with greater increases in cardiac vagal control after the challenge. In contrast, among the individuals with lower levels of trait anxiety, changes in perceived stress had no impact on vagal recovery. Therefore, change in perceived stress moderates the relationship of trait anxiety, but not trait anger, to vagal recovery from cognitive challenge. PMID:21945037
Luiz Augusto Perandini
Full Text Available The aim of this study was to evaluate the relationship between vagal withdrawal and reactivation indices and maximal running velocity (Vmax in taekwondo athletes. Eleven elite taekwondo athletes (seven men: 23.7±2.2 years, 72.4±7.0 kg, 178.8±7.5 cm, 51.9±2.9 ml.kg-1.min-1, and four women: 18.8±1.5 years, 61.8±1.8 kg, 168.0±4.4 cm, 41.6±2.4 ml.kg-1.min-1 performed a graded exercise test until exhaustion, with the last complete stage performed corresponding to Vmax. Heart rate variability (HRV parameters were calculated at 1-minute intervals until 85% of maximum HR and plotted against time for the estimation of vagal withdrawal indices (τ, amplitude (A and area under the curve (AUC. Vagal reactivation indices were determined based on HR recovery during the first 60 s (HRR60s and negative reciprocal of the slope of the regression line obtained during the first 30 s of HRR (T30. The vagal withdrawal parameters A and AUC were moderately and significantly correlated with Vmax (r = 0.61-0.71, P 0.05. T30 and HRR60s were also significantly correlated with Vmax (r = -0.77 and 0.64, P < 0.05, respectively. The present results showed that vagal withdrawal (A and AUC and vagal reactivation (T30 and HRR60s indices were significantly correlated with Vmax, suggesting that these indices can be used for the evaluation and monitoring of aerobic fitness in taekwondo athletes.
Simon R Foster
Full Text Available G protein-coupled receptors (GPCRs are critical for cardiovascular physiology. Cardiac cells express >100 nonchemosensory GPCRs, indicating that important physiological and potential therapeutic targets remain to be discovered. Moreover, there is a growing appreciation that members of the large, distinct taste and odorant GPCR families have specific functions in tissues beyond the oronasal cavity, including in the brain, gastrointestinal tract and respiratory system. To date, these chemosensory GPCRs have not been systematically studied in the heart. We performed RT-qPCR taste receptor screens in rodent and human heart tissues that revealed discrete subsets of type 2 taste receptors (TAS2/Tas2 as well as Tas1r1 and Tas1r3 (comprising the umami receptor are expressed. These taste GPCRs are present in cultured cardiac myocytes and fibroblasts, and by in situ hybridization can be visualized across the myocardium in isolated cardiac cells. Tas1r1 gene-targeted mice (Tas1r1(Cre/Rosa26(tdRFP strikingly recapitulated these data. In vivo taste receptor expression levels were developmentally regulated in the postnatal period. Intriguingly, several Tas2rs were upregulated in cultured rat myocytes and in mouse heart in vivo following starvation. The discovery of taste GPCRs in the heart opens an exciting new field of cardiac research. We predict that these taste receptors may function as nutrient sensors in the heart.
Gámiz, Fernando; Gallo, Milagros
Taste aversion learning exhibits advantages for research on memory brain systems and its reorganization throughout life. A review of the effects of aging on taste memory abilities offers a complex picture showing preserved, impaired, and enhanced functions. Some of the age-related changes in taste memory seem to be associated with an altered temporal processing. Longer taste–illness delays can be introduced for acquisition of conditioned taste aversions and the modulation of taste learning by the temporal context is absent in naïve old rats. It is suggested that an altered hippocampal function is involved in the peculiar performance of these rats. Evidence is also presented which suggests that hippocampal-dependent taste memory can be reactivated by previous learning experiences in old rats. Results obtained after reversible inactivation of the dorsal Hippocampus by tetrodotoxin (TTX) in old rats support such a view. Therefore, the interaction between the previous experience and acute brain interventions should be taken into account when studying the effect of aging on taste memory. PMID:22073032
Wang, Feng-Bin; Liao, Yi-Han; Wang, Yao-Chen
The inner thoracic cavity is lined by the parietal pleura, and the lung lobes are covered by the visceral pleura. The parietal and visceral plurae form the pleural cavity that has negative pressure within to enable normal respiration. The lung tissues are bilaterally innervated by vagal and spinal nerves, including sensory and motor components. This complicated innervation pattern has made it difficult to discern the vagal vs. spinal processes in the pulmonary visceral pleura. With and without vagotomy, we identified vagal nerve fibres and endings distributed extensively in the visceral pleura ('P'-type nerve endings) and triangular ligaments ('L'-type nerve endings) by injecting wheat germ agglutinin-horseradish peroxidase as a tracer into the nucleus of solitary tract or nodose ganglion of male Sprague-Dawley rats. We found the hilar and non-hilar vagal pulmonary pleural innervation pathways. In the hilar pathway, vagal sub-branches enter the hilum and follow the pleural sheet to give off the terminal arborizations. In the non-hilar pathway, vagal sub-branches run caudally along the oesophagus and either directly enter the ventral-middle-mediastinal left lobe or follow the triangular ligaments to enter the left and inferior lobe. Both vagi innervate: (i) the superior, middle and accessory lobes on the ventral surfaces that face the heart; (ii) the dorsal-rostral superior lobe; (iii) the dorsal-caudal left lobe; and (iv) the left triangular ligament. Innervated only by the left vagus is: (i) the ventral-rostral and dorsal-rostral left lobe via the hilar pathway; (ii) the ventral-middle-mediastinal left lobe and the dorsal accessory lobe that face the left lobe via the non-hilar pathway; and (iii) the ventral-rostral inferior lobe that faces the heart. Innervated only by the right vagus, via the non-hilar pathway, is: (i) the inferior (ventral and dorsal) and left (ventral only) lobe in the area near the triangular ligament; (ii) the dorsal-middle-mediastinal left
Evans, Randolph W
A 72-year-old man presented with a 7-week history of a new onset constant severe right-sided headache associated with redness and tearing of the right eye, which resolved on indomethacin due to nonmetastatic small cell carcinoma producing a large suprahilar mass. This is the first case report of a hemicrania continua-like headache with autonomic features due to lung cancer. I propose the term "vagal cephalalgia" to include headache and/or facial pain due to nonmetastatic lung cancer and cardiac cephalalgia which result from vagal afferent stimulation.
Feng, Pu; Huang, Liquan; Wang, Hong
The mammalian taste bud is an onion-shaped epithelial structure with 50-100 tightly packed cells, including taste receptor cells, supporting cells, and basal cells. Taste receptor cells detect nutrients and toxins in the oral cavity and transmit the sensory information to gustatory nerve endings in the buds. Supporting cells may play a role in the clearance of excess neurotransmitters after their release from taste receptor cells. Basal cells are precursor cells that differentiate into mature taste cells. Similar to other epithelial cells, taste cells turn over continuously, with an average life span of about 8-12 days. To maintain structural homeostasis in taste buds, new cells are generated to replace dying cells. Several recent studies using genetic lineage tracing methods have identified populations of progenitor/stem cells for taste buds, although contributions of these progenitor/stem cell populations to taste bud homeostasis have yet to be fully determined. Some regulatory factors of taste cell differentiation and degeneration have been identified, but our understanding of these aspects of taste bud homoeostasis remains limited. Many patients with various diseases develop taste disorders, including taste loss and taste distortion. Decline in taste function also occurs during aging. Recent studies suggest that disruption or alteration of taste bud homeostasis may contribute to taste dysfunction associated with disease and aging.
North, Adrian C
Several studies have investigated the relationship between (usually a narrow set of) personality dimensions and liking for a small number of individual musical styles. To date there has been no attempt to investigate, within a single methodology, the extent to which personality factors correlate with liking for a very wide range of musical styles. To address this, 36,518 participants rated their liking for 104 musical styles, completed a short form of the Big 5 personality inventory, and provided other data about their favorite musical styles. Personality factors were related to both liking for the musical styles and participants' reasons for listening to this music. However, on the whole these latter variables were related more closely to participants' age, sex, and income than to Big 5 scores. Thus, personality is related to musical taste, but other individual differences are arguably related more closely.
Yang, Hyekyung; Cong, Wei-Na; Yoon, Jeong Seon; Egan, Josephine M
Vismodegib, a highly selective inhibitor of hedgehog (Hh) pathway, is an approved treatment for basal-cell carcinoma. Patients on treatment with vismodegib often report profound alterations in taste sensation. The cellular mechanisms underlying the alterations have not been studied. Sonic Hh (Shh) signaling is required for cell growth and differentiation. In taste buds, Shh is exclusively expressed in type IV taste cells, which are undifferentiated basal cells and the precursors of the three types of taste sensing cells. Thus, we investigated if vismodegib has an inhibitory effect on taste cell turnover because of its known effects on Hh signaling. We gavaged C57BL/6J male mice daily with either vehicle or 30 mg/kg vismodegib for 15 weeks. The gustatory behavior and immunohistochemical profile of taste cells were examined. Vismodegib-treated mice showed decreased growth rate and behavioral responsivity to sweet and bitter stimuli, compared to vehicle-treated mice. We found that vismodegib-treated mice had significant reductions in taste bud size and numbers of taste cells per taste bud. Additionally, vismodegib treatment resulted in decreased numbers of Ki67- and Shh-expressing cells in taste buds. The numbers of phospholipase Cβ2- and α-gustducin-expressing cells, which contain biochemical machinery for sweet and bitter sensing, were reduced in vismodegib-treated mice. Furthermore, vismodegib treatment resulted in reduction in numbers of T1R3, glucagon-like peptide-1, and glucagon-expressing cells, which are known to modulate sweet taste sensitivity. These results suggest that inhibition of Shh signaling by vismodegib treatment directly results in alteration of taste due to local effects in taste buds. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.
Wu, Xiao; Tahara, Yusuke; Toko, Kiyoshi; Kuriyaki, Hisao
In order to solve the unconcern to usefulness of learning science among high school students in Japan, we developed a simple fabricated taste sensor with sensitivity and selectivity to each taste quality, which can be applied in science class. A commercialized Teflon membrane was used as the polymer membrane holding lipids. In addition, a non-adhesive method is considered to combine the membrane and the sensor electrode using a plastic cap which is easily accessible. The taste sensor for education fabricated in this way showed a good selectivity and sensitivity. By adjusting the composition of trioctylmethylammonium chloride (TOMA) and phosphoric acid di(2-ethylhexyl) ester (PAEE) included in lipid solution, we improved the selectivity of this simple taste sensor to saltiness and sourness. To verify this taste sensor as a useful science teaching material for science class, we applied this taste sensor into a science class for university students. By comparing the results between the sensory test and the sensor response, humans taste showed the same tendency just as the sensor response, which proved the sensor as a useful teaching material for science class.
Masek, Pavel; Keene, Alex C
Taste is the primary sensory system for detecting food quality and palatability. Drosophila detects five distinct taste modalities that include sweet, bitter, salt, water, and the taste of carbonation. Of these, sweet-sensing neurons appear to have utility for the detection of nutritionally rich food while bitter-sensing neurons signal toxicity and confer repulsion. Growing evidence in mammals suggests that taste for fatty acids (FAs) signals the presence of dietary lipids and promotes feeding. While flies appear to be attracted to fatty acids, the neural basis for fatty acid detection and attraction are unclear. Here, we demonstrate that a range of FAs are detected by the fly gustatory system and elicit a robust feeding response. Flies lacking olfactory organs respond robustly to FAs, confirming that FA attraction is mediated through the gustatory system. Furthermore, flies detect FAs independent of pH, suggesting the molecular basis for FA taste is not due to acidity. We show that low and medium concentrations of FAs serve as an appetitive signal and they are detected exclusively through the same subset of neurons that sense appetitive sweet substances, including most sugars. In mammals, taste perception of sweet and bitter substances is dependent on phospholipase C (PLC) signaling in specialized taste buds. We find that flies mutant for norpA, a Drosophila ortholog of PLC, fail to respond to FAs. Intriguingly, norpA mutants respond normally to other tastants, including sucrose and yeast. The defect of norpA mutants can be rescued by selectively restoring norpA expression in sweet-sensing neurons, corroborating that FAs signal through sweet-sensing neurons, and suggesting PLC signaling in the gustatory system is specifically involved in FA taste. Taken together, these findings reveal that PLC function in Drosophila sweet-sensing neurons is a conserved molecular signaling pathway that confers attraction to fatty acids.
Full Text Available Taste is the primary sensory system for detecting food quality and palatability. Drosophila detects five distinct taste modalities that include sweet, bitter, salt, water, and the taste of carbonation. Of these, sweet-sensing neurons appear to have utility for the detection of nutritionally rich food while bitter-sensing neurons signal toxicity and confer repulsion. Growing evidence in mammals suggests that taste for fatty acids (FAs signals the presence of dietary lipids and promotes feeding. While flies appear to be attracted to fatty acids, the neural basis for fatty acid detection and attraction are unclear. Here, we demonstrate that a range of FAs are detected by the fly gustatory system and elicit a robust feeding response. Flies lacking olfactory organs respond robustly to FAs, confirming that FA attraction is mediated through the gustatory system. Furthermore, flies detect FAs independent of pH, suggesting the molecular basis for FA taste is not due to acidity. We show that low and medium concentrations of FAs serve as an appetitive signal and they are detected exclusively through the same subset of neurons that sense appetitive sweet substances, including most sugars. In mammals, taste perception of sweet and bitter substances is dependent on phospholipase C (PLC signaling in specialized taste buds. We find that flies mutant for norpA, a Drosophila ortholog of PLC, fail to respond to FAs. Intriguingly, norpA mutants respond normally to other tastants, including sucrose and yeast. The defect of norpA mutants can be rescued by selectively restoring norpA expression in sweet-sensing neurons, corroborating that FAs signal through sweet-sensing neurons, and suggesting PLC signaling in the gustatory system is specifically involved in FA taste. Taken together, these findings reveal that PLC function in Drosophila sweet-sensing neurons is a conserved molecular signaling pathway that confers attraction to fatty acids.
Taste receptor cells encounter chemicals in foods and transmit this information to the gustatory neurons, which convey it further to the gustatory relay nuclei in the lower brainstem. Characterizing neurons involved in the transmission of gustatory information in the peripheral and central nervous systems helps us better understand how we perceive and discriminate tastes. However, it is difficult to anatomically identify them. Using cell-type-specific promoters/enhancers and a transneuronal t...
Ruud M Buijs
Full Text Available BACKGROUND: Recently the vagal output of the central nervous system has been shown to suppress the innate immune defense to pathogens. Here we investigated by anatomical and physiological techniques the communication of the brain with the spleen and provided evidence that the brain has the capacity to stimulate the production of antigen specific antibodies by its parasympathetic autonomic output. METHODOLOGY/PRINCIPAL FINDINGS: This conclusion was reached by successively demonstrating that: 1. The spleen receives not only sympathetic input but also parasympathetic input. 2. Intravenous trinitrophenyl-ovalbumin (TNP-OVA does not activate the brain and does not induce an immune response. 3. Intravenous TNP-OVA with an inducer of inflammation; lipopolysaccharide (LPS, activates the brain and induces TNP-specific IgM. 4. LPS activated neurons are in the same areas of the brain as those that provide parasympathetic autonomic information to the spleen, suggesting a feed back circuit between brain and immune system. Consequently we investigated the interaction of the brain with the spleen and observed that specific parasympathetic denervation but not sympathetic denervation of the spleen eliminates the LPS-induced antibody response to TNP-OVA. CONCLUSIONS/SIGNIFICANCE: These findings not only show that the brain can stimulate antibody production by its autonomic output, it also suggests that the power of LPS as adjuvant to stimulate antibody production may also depend on its capacity to activate the brain. The role of the autonomic nervous system in the stimulation of the adaptive immune response may explain why mood and sleep have an influence on antibody production.
Thoma, Vladimiros; Knapek, Stephan; Arai, Shogo; Hartl, Marion; Kohsaka, Hiroshi; Sirigrivatanawong, Pudith; Abe, Ayako; Hashimoto, Koichi; Tanimoto, Hiromu
Finding food sources is essential for survival. Insects detect nutrients with external taste receptor neurons. Drosophila possesses multiple taste organs that are distributed throughout its body. However, the role of different taste organs in feeding remains poorly understood. By blocking subsets of sweet taste receptor neurons, we show that receptor neurons in the legs are required for immediate sugar choice. Furthermore, we identify two anatomically distinct classes of sweet taste receptor neurons in the leg. The axonal projections of one class terminate in the thoracic ganglia, whereas the other projects directly to the brain. These two classes are functionally distinct: the brain-projecting neurons are involved in feeding initiation, whereas the thoracic ganglia-projecting neurons play a role in sugar-dependent suppression of locomotion. Distinct receptor neurons for the same taste quality may coordinate early appetitive responses, taking advantage of the legs as the first appendages to contact food.
Tavassoli, T.; Baron-Cohen, S.
Sensory issues are widely reported in Autism Spectrum Conditions (ASC). Since taste perception is one of the least studied senses in ASC we explored taste identification in adults with ASC (12 males, 11 females) compared to control participants (14 males, 12 females). "Taste strips" were used to measure taste identification overall, as well as…
Perlman, Susan B.; Camras, Linda A.; Pelphrey, Kevin A.
This study examined relationships among parents' physiological regulation, their emotion socialization behaviors, and their children's emotion knowledge. Parents' resting cardiac vagal tone was measured, and parents provided information regarding their socialization behaviors and family emotional expressiveness. Their 4- or 5-year-old children (N…
Nelson, David W; Liu, Xiaowen; Holst, Jens Juul
Small bowel resection stimulates intestinal adaptive growth by a neuroendocrine process thought to involve both sympathetic and parasympathetic innervation and enterotrophic hormones such as glucagon-like peptide-2 (GLP-2). We investigated whether capsaicin-sensitive vagal afferent neurons are es...
de La Serre, Claire B; de Lartigue, Guillaume; Raybould, Helen E
Bacterially derived factors are implicated in the causation and persistence of obesity. Ingestion of a high fat diet in rodents and obesity in human subjects is associated with chronic elevation of low plasma levels of lipopolysaccharide (LPS), a breakdown product of Gram-negative bacteria. The terminals of vagal afferent neurons are positioned within the gut mucosa to convey information from the gut to the brain to regulate food intake and are responsive to LPS. We hypothesized that chronic elevation of LPS could alter vagal afferent signaling. We surgically implanted osmotic mini-pumps that delivered a constant, low-dose of LPS into the intraperitoneal cavity of rats (12.5 μg/kg/hr for 6 weeks). LPS-treated rats developed hyperphagia and showed marked changes in vagal afferent neuron function. Chronic LPS treatment reduced vagal afferent leptin signaling, characterized by a decrease in leptin-induced STAT3 phosphorylation. In addition, LPS treatment decreased cholecystokinin-induced satiety. There was no alteration in leptin signaling in the hypothalamus. These findings offer a mechanism by which a change in gut microflora can promote hyperphagia, possibly leading to obesity. Copyright © 2014. Published by Elsevier Inc.
Huang, Yijen A; Maruyama, Yutaka; Stimac, Robert; Roper, Stephen D
Taste buds contain two types of cells that directly participate in taste transduction - receptor (Type II) cells and presynaptic (Type III) cells. Receptor cells respond to sweet, bitter and umami taste stimulation but until recently the identity of cells that respond directly to sour (acid) tastants has only been inferred from recordings in situ, from behavioural studies, and from immunostaining for putative sour transduction molecules. Using calcium imaging on single isolated taste cells and with biosensor cells to identify neurotransmitter release, we show that presynaptic (Type III) cells specifically respond to acid taste stimulation and release serotonin. By recording responses in cells isolated from taste buds and in taste cells in lingual slices to acetic acid titrated to different acid levels (pH), we also show that the active stimulus for acid taste is the membrane-permeant, uncharged acetic acid moiety (CH(3)COOH), not free protons (H(+)). That observation is consistent with the proximate stimulus for acid taste being intracellular acidification, not extracellular protons per se. These findings may also have implications for other sensory receptors that respond to acids, such as nociceptors.
Zhang, Feng; Klebansky, Boris; Fine, Richard M.; Xu, Hong; Pronin, Alexey; Liu, Haitian; Tachdjian, Catherine; Li, Xiaodong
Umami is one of the 5 basic taste qualities. The umami taste of L-glutamate can be drastically enhanced by 5′ ribonucleotides and the synergy is a hallmark of this taste quality. The umami taste receptor is a heteromeric complex of 2 class C G-protein-coupled receptors, T1R1 and T1R3. Here we elucidate the molecular mechanism of the synergy using chimeric T1R receptors, site-directed mutagenesis, and molecular modeling. We propose a cooperative ligand-binding model involving the Venus flytrap domain of T1R1, where L-glutamate binds close to the hinge region, and 5′ ribonucleotides bind to an adjacent site close to the opening of the flytrap to further stabilize the closed conformation. This unique mechanism may apply to other class C G-protein-coupled receptors. PMID:19104071
Iwatsuki, Ken; Uneyama, Hisayuki
Recent advances in molecular biology have led to the investigation of the molecular mechanism by which chemicals such as odors and tastants are perceived by specific chemosensory organs. For example, G protein-coupled receptors expressed within the nasal epithelium and taste receptors in the oral cavity have been identified as odorant and taste receptors, respectively. However, there is much evidence to indicate that these chemosensory receptors are not restricted to primary chemosensory cells; they are also expressed and have function in other cells such as those in the airways and gastrointestinal (GI) tract. This short review describes the possible mechanisms by which taste signal transduction occurs in the oral cavity and tastants/nutrients are sensed in the GI tract by taste-like cells, mainly enteroendocrine and brush cells. Furthermore, it discusses the future perspectives of chemosensory studies.
do Carmo, Jussara M; Hall, John E; da Silva, Alexandre A
This study tested whether leptin restores sympathetic-vagal balance, heart rate (HR) variability, and cardiac baroreflex sensitivity (BRS) in streptozotocin (STZ)-induced diabetes. Sprague-Dawley rats were instrumented with arterial and venous catheters, and a cannula was placed in the lateral ventricle for intracerebroventricular (ICV) leptin infusion. Blood pressure (BP) and HR were monitored by telemetry. BRS and HR variability were estimated by linear regression between HR and BP responses to phenylephrine or sodium nitroprusside and autoregressive spectral analysis. Measurements were made during control period, 7 days after induction of diabetes, and 7 days after ICV leptin infusion. STZ diabetes was associated with hyperglycemia (422 +/- 17 mg/dl) and bradycardia (-79 +/- 4 beats/min). Leptin decreased glucose levels (165 +/- 16 mg/dl) and raised HR to control values (303 +/- 10 to 389 +/- 10 beats/min). Intrinsic HR (IHR) and chronotropic responses to a full-blocking dose of propranolol and atropine were reduced during diabetes (260 +/- 7 vs. 316 +/- 6, -19 +/- 2 vs. -43 +/- 6, and 39 +/- 3 vs. 68 +/- 8 beats/min), and leptin treatment restored these variables to normal (300 +/- 7, -68 +/- 10, and 71 +/- 8 beats/min). Leptin normalized BRS (bradycardia, -2.6 +/- 0.3, -1.7 +/- 0.2, and -3.0 +/- 0.5; and tachycardia, -3.2 +/- 0.4, -1.9 +/- 0.3, and -3.4 +/- 0.3 beats.min(-1).mmHg(-1) for control, diabetes, and leptin) and HR variability (23 +/- 4 to 11 +/- 1.5 ms2). Chronic glucose infusion to maintain hyperglycemia during leptin infusion did not alter the effect of leptin on IHR but abolished the improved BRS. These results show rapid impairment of autonomic nervous system control of HR after the induction of diabetes and that central nervous system actions of leptin can abolish the hyperglycemia as well as the altered IHR and BRS in STZ-induced diabetes.
Zhang, Wei; Chen, Peihua; Xiao, Lidan; Liu, Qingjun; Wang, Ping
Taste receptor cells as the fundamental units of taste sensation are not only passive receivers to outside stimulus, but some primary process for the signals and information. In this paper, an innovation on acquisition of taste receptor cells was introduced and larger amount of cells could be obtained. A multichannel microelectrode array (MEA) system was applied in signal recording, which is used in non-invasive, multiple and simultaneous extracellular recording of taste receptor cells. The cells were treated with sour solutions of different pHs, and the relations between concentration of hydrogen and firing rate were observed. Firing rates on pH 7, pH 4 and pH 2 were approximately 1.38±0.01 (MEAN±SE)/s, 1.61±0.07/s and 2.75+0.15/s.
Kinnamon, Sue C.
Taste buds are the transducing endorgans of gustation. Each taste bud comprises 50–100 elongated cells, which extend from the basal lamina to the surface of the tongue, where their apical microvilli encounter taste stimuli in the oral cavity. Salts and acids utilize apically located ion channels for transduction, while bitter, sweet and umami (glutamate) stimuli utilize G protein coupled receptors (GPCRs) and second messenger signaling mechanisms. This review will focus on GPCR signaling mechanisms. Two classes of taste GPCRs have been identified, the T1Rs for sweet and umami (glutamate) stimuli, and the T2Rs for bitter stimuli. These low affinity GPCRs all couple to the same downstream signaling effectors that include Gβγ activation of PLCβ2, IP3-mediated release of Ca2+ from intracellular stores, and Ca2+-dependent activation of the monovalent selective cation channel, TrpM5. These events lead to membrane depolarization, action potentials, and release of ATP as a transmitter to activate gustatory afferents. The Gα subunit, α-gustducin, activates a phosphodiesterase to decrease intracellular cAMP levels, although the precise targets of cAMP have not been identified. With the molecular identification of the taste GPCRs, it has become clear that taste signaling is not limited to taste buds, but occurs in many cell types of the airways. These include solitary chemosensory cells, ciliated epithelial cells, and smooth muscle cells. Bitter receptors are most abundantly expressed in the airways, where they respond to irritating chemicals and promote protective airway reflexes, utilizing the same downstream signaling effectors as taste cells. PMID:21481196
Full Text Available Background. An active device that downregulates abdominal vagal signalling has resulted in significant weight loss in feasibility studies. Objective. To prospectively evaluate the effect of intermittent vagal blocking (VBLOC on weight loss, glycemic control, and blood pressure (BP in obese subjects with DM2. Methods. Twenty-eight subjects were implanted with a VBLOC device (Maestro Rechargeable System at 5 centers in an open-label study. Effects on weight loss, HbA1c, fasting blood glucose, and BP were evaluated at 1 week to 12 months. Results. 26 subjects (17 females/9 males, 51±2 years, BMI 37±1 kg/m2, mean ± SEM completed 12 months followup. One serious adverse event (pain at implant site was easily resolved. At 1 week and 12 months, mean excess weight loss percentages (% EWL were 9±1% and 25±4% (P<0.0001, and HbA1c declined by 0.3±0.1% and 1.0±0.2% (P=0.02, baseline 7.8±0.2%. In DM2 subjects with elevated BP (n=15, mean arterial pressure reduced by 7±3 mmHg and 8±3 mmHg (P=0.04, baseline 100 ± 2 mmHg at 1 week and 12 months. All subjects MAP decreased by 3 ± 2 mmHg (baseline 95 ± 2 mmHg at 12 months. Conclusions. VBLOC was safe in obese DM2 subjects and associated with meaningful weight loss, early and sustained improvements in HbA1c, and reductions in BP in hypertensive DM2 subjects. This trial is registered with ClinicalTrials.gov NCT00555958.
Chen, Jin-Long; Shiau, Yuo-Hsien; Tseng, Yin-Jiun; Chiu, Hung-Wen; Hsiao, Tzu-Chien; Wessel, Niels; Kurths, Jürgen; Chu, Woei-Chyn
Despite many previous studies on the association between hyperthyroidism and the hyperadrenergic state, controversies still exist. Detrended fluctuation analysis (DFA) is a well recognized method in the nonlinear analysis of heart rate variability (HRV), and it has physiological significance related to the autonomic nervous system. In particular, an increased short-term scaling exponent α1 calculated from DFA is associated with both increased sympathetic activity and decreased vagal activity. No study has investigated the DFA of HRV in hyperthyroidism. This study was designed to assess the sympathovagal balance in hyperthyroidism. We performed the DFA along with the linear analysis of HRV in 36 hyperthyroid Graves’ disease patients (32 females and 4 males; age 30 ± 1 years, means ± SE) and 36 normal controls matched by sex, age and body mass index. Compared with the normal controls, the hyperthyroid patients revealed a significant increase ( Phyperthyroid 1.28±0.04 versus control 0.91±0.02), long-term scaling exponent α2 (1.05±0.02 versus 0.90±0.01), overall scaling exponent α (1.11±0.02 versus 0.89±0.01), low frequency power in normalized units (LF%) and the ratio of low frequency power to high frequency power (LF/HF); and a significant decrease ( Phyperthyroidism is characterized by concurrent sympathetic activation and vagal withdrawal. This sympathovagal imbalance state in hyperthyroidism helps to explain the higher prevalence of atrial fibrillation and exercise intolerance among hyperthyroid patients.
Burgess, Adrian P; Fouquet, Nathalie C; Seri, Stefano; Hawken, Malcolm B; Heard, Andrew; Neasham, David; Little, Mark P; Elliott, Paul
Terrestrial Trunked Radio (TETRA) is a telecommunications system widely used by police and emergency services around the world. The Stewart Report on mobile telephony and health raised questions about possible health effects associated with TETRA signals. This study investigates possible effects of TETRA signals on the electroencephalogram and electrocardiogram in human volunteers. Blinded randomized provocation study with a standardized TETRA signal or sham exposure. In the first of two experiments, police officers had a TETRA set placed first against the left temple and then the upper-left quadrant of the chest and the electroencephalogram was recorded during rest and active cognitive processing. In the second experiment, volunteers were subject to chest exposure of TETRA whilst their electroencephalogram and heart rate variability derived from the electrocardiogram were recorded. In the first experiment, we found that exposure to TETRA had consistent neurophysiological effects on the electroencephalogram, but only during chest exposure, in a pattern suggestive of vagal nerve stimulation. In the second experiment, we observed changes in heart rate variability during exposure to TETRA but the electroencephalogram effects were not replicated. Observed effects of exposure to TETRA signals on the electroencephalogram (first experiment) and electrocardiogram are consistent with vagal nerve stimulation in the chest by TETRA. However given the small effect on heart rate variability and the lack of consistency on the electroencephalogram, it seems unlikely that this will have a significant impact on health. Long-term monitoring of the health of the police force in relation to TETRA use is on-going. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
Gregory M Holmes
Full Text Available Despite the widely recognized prevalence of gastric, colonic and anorectal dysfunction after SCI, significant knowledge gaps persist regarding the mechanisms leading to post-SCI gastrointestinal (GI impairments. Briefly, the regulation of GI function is governed by a mix of parasympathetic, sympathetic and enteric neurocircuitry. Unlike the intestines, the stomach is dominated by parasympathetic (vagal control whereby gastric sensory information is transmitted via the afferent vagus nerve to neurons of the nucleus tractus solitarius (NTS. The NTS integrates this sensory information with signals from throughout the CNS. Glutamatergic and GABAergic NTS neurons project to other nuclei, including the preganglionic parasympathetic neurons of the dorsal motor nucleus of the vagus (DMV. Finally, axons from the DMV project to gastric myenteric neurons, again, through the efferent vagus nerve. SCI interrupts descending input to the lumbosacral spinal cord neurons that modulate colonic motility and evacuation reflexes. In contrast, vagal neurocircuitry remains anatomically intact after injury. This review presents evidence that unlike the post-SCI loss of supraspinal control which leads to colonic and anorectal dysfunction, gastric dysmotility occurs as an indirect or secondary pathology following SCI. Specifically, emerging data points toward diminished sensitivity of vagal afferents to GI neuroactive peptides, neurotransmitters and, possibly, macronutrients. The neurophysiological properties of rat vagal afferent neurons are highly plastic and can be altered by injury or energy balance. A reduction of vagal afferent signaling to NTS neurons may ultimately bias NTS output toward unregulated GABAergic transmission onto gastric-projecting DMV neurons. The resulting gastroinhibitory signal may be one mechanism leading to upper GI dysmotility following SCI.
Steinbach, Silke; Reindl, Wolfgang; Dempfle, Astrid; Schuster, Anna; Wolf, Petra; Hundt, Walter; Huber, Wolfgang
To investigate the olfactory/gustatory functions of patients with inflammatory bowel disease (IBD) by smell/taste tests, and to determine if disease activity or medication might influence the olfactory/gustatory functions of patients. In total, 59 IBD patients (37 Crohn's disease (CD) and 22 ulcerative colitis (UC) patients) were studied using "Sniffin' sticks" and "taste strips" for olfactory and gustatory tests, respectively, and compared to healthy controls and published normative data. Among IBD (CD and UC) patients, the values for odor threshold, but not for odor identification or discrimination, were significantly lower than that of the normative data. Further, these patients showed lower values than the normative taste values and the control group for all tastes, except sour; 57.6% of the IBD patients were hyposmic, while 30.5% were hypogeusic. Subjective self-assessments showed that the patients were not aware of their reduced olfactory/gustatory functions. There were no relevant differences in taste and smell abilities between the CD and UC patients. Disease activity and treatment did not influence the olfactory/gustatory functions. IBD (CD and UC) patients exhibited significant reductions in the olfactory and gustatory functions. Therefore, patients should be tested by smell/taste tests, in order to be adequately informed of their olfactory/gustatory functions and provided an understanding of how to overcome their limitations, and thus improve their quality of life.
Nachtigal, Danielle; Hammond, Samuel; Lim, Juyun
Psychophysical studies of interactions between retronasal olfaction and taste have focused most often on the enhancement of tastes by odors, which has been attributed primarily to a response bias (i.e., halo dumping). Based upon preliminary evidence that retronasal odors could also be enhanced by taste, the present study measured both forms of enhancement using appropriate response categories. In the first experiment, subjects rated taste (“sweet,” “sour,” “salty,” and “bitter”) and odor (“other”) intensity for aqueous samples of 3 tastants (sucrose, NaCl, and citric acid) and 3 odorants (vanillin, citral, and furaneol), both alone and in taste–odor mixtures. The results showed that sucrose, but not the other taste stimuli, significantly increased the perceived intensity of all 3 odors. Enhancement of tastes by odors was inconsistent and generally weaker than enhancement of odors by sucrose. A second experiment used a flavored beverage and a custard dessert to test whether the findings from the first experiment would hold for the perception of actual foods. Adding sucrose significantly enhanced the intensity of “cherry” and “vanilla” flavors, whereas adding vanillin did not significantly enhance the intensity of sweetness. It is proposed that enhancement of retronasal odors by a sweet stimulus results from an adaptive sensory mechanism that serves to increase the salience of the flavor of nutritive foods. PMID:21798851
Full Text Available Tongue has taste buds that contain taste receptor which affected by many factors, including smoking habit. Objective: To analyze the differences of sweet and bitter taste sensitivity in the pedicab driver clove cigarette smokers compared to non-smokers in Medan Padang Bulan. Methods: This study was conducted by placing the sweet taste strips and bitter taste strips on four taste receptors of the tongue, with increasing solution concentration in 74 subjects. This was a cross sectional study on pedicab driver population in Medan Padang Bulan. Results: There were differences between clove cigarette smokers and non-smokers on sweet taste examination (p<0.005. There was a difference between clove cigarette smokers and non-smokers on examination bitter taste receptors (p<0.005. On the clove cigarette smokers, there was no significant difference between sweet taste and bitter taste on the receptors itself. Conclusion: Non-smokers are more sensitive to sweet taste than the clove cigarette smokers. Bitter taste sensitivity is greater in cigarettes smokers than in non-smokers. Taste receptors on all location of the tongue could taste sweet and bitter substances, but a certain location of taste receptors were more sensitive compared to others.
Adachi, Ryota; Sasaki, Yuko; Morita, Hiromi; Komai, Michio; Shirakawa, Hitoshi; Goto, Tomoko; Furuyama, Akira; Isono, Kunio
Transgenic Drosophila expressing human T2R4 and T2R38 bitter-taste receptors or PKD2L1 sour-taste receptor in the fly gustatory receptor neurons and other tissues were prepared using conventional Gal4/UAS binary system. Molecular analysis showed that the transgene mRNAs are expressed according to the tissue specificity of the Gal4 drivers. Transformants expressing the transgene taste receptors in the fly taste neurons were then studied by a behavioral assay to analyze whether transgene chemoreceptors are functional and coupled to the cell response. Since wild-type flies show strong aversion against the T2R ligands as in mammals, the authors analyzed the transformants where the transgenes are expressed in the fly sugar receptor neurons so that they promote feeding ligand-dependently if they are functional and activate the neurons. Although the feeding preference varied considerably among different strains and individuals, statistical analysis using large numbers of transformants indicated that transformants expressing T2R4 showed a small but significant increase in the preference for denatonium and quinine, the T2R4 ligands, as compared to the control flies, whereas transformants expressing T2R38 did not. Similarly, transformants expressing T2R38 and PKD2L1 also showed a similar preference increase for T2R38-specific ligand phenylthiocarbamide (PTC) and a sour-taste ligand, citric acid, respectively. Taken together, the transformants expressing mammalian taste receptors showed a small but significant increase in the feeding preference that is taste receptor and also ligand dependent. Although future improvements are required to attain performance comparable to the endogenous robust response, Drosophila taste neurons may serve as a potential in vivo heterologous expression system for analyzing chemoreceptor function.
Veedfald, Simon; Plamboeck, Astrid; Hartmann, Bolette
hyperglycemia inhibits secretion. The glucose sensing mechanism has yet to be determined but may involve a vagal pathway. To investigate the role of enteral stimuli with or without intact vagal innervation, while controlling for the glucose excursion caused by the OGTT, we measured PP plasma levels by an in...... from the DPP-4i day to determine the potential effect of DPP-4-cleaved peptides on PP secretion. In both vagotomized and controls, oral glucose elicited PP secretion. In controls, but not in the vagotomized participants, intravenous glucose significantly inhibited PP secretion suggesting a vagal...
Uitterdijk, André; Yetgin, Tuncay; te Lintel Hekkert, Maaike; Sneep, Stefan; Krabbendam-Peters, Ilona; van Beusekom, Heleen M M; Fischer, Trent M; Cornelussen, Richard N; Manintveld, Olivier C; Merkus, Daphne; Duncker, Dirk J
Vagal nerve stimulation (VNS) started prior to, or during, ischemia has been shown to reduce infarct size. Here, we investigated the effect of VNS when started just prior to, and continued during early, reperfusion on infarct size and no-reflow and studied the underlying mechanisms. For this purpose, swine (13 VNS, 10 sham) underwent 45 min mid-LAD occlusion followed by 120 min of reperfusion. VNS was started 5 min prior to reperfusion and continued until 15 min of reperfusion. Area at risk, area of no-reflow (% of infarct area) and infarct size (% of area at risk), circulating cytokines, and regional myocardial leukocyte influx were assessed after 120 min of reperfusion. VNS significantly reduced infarct size from 67 ± 2 % in sham to 54 ± 5 % and area of no-reflow from 54 ± 6 % in sham to 32 ± 6 %. These effects were accompanied by reductions in neutrophil (~40 %) and macrophage (~60 %) infiltration in the infarct area (all p < 0.05), whereas systemic circulating plasma levels of TNFα and IL6 were not affected. The degree of cardioprotection could not be explained by the VNS-induced bradycardia or the VNS-induced decrease in the double product of heart rate and left ventricular systolic pressure. In the presence of NO-synthase inhibitor LNNA, VNS no longer attenuated infarct size and area of no-reflow, which was paralleled by similarly unaffected regional leukocyte infiltration. In conclusion, VNS is a promising novel adjunctive therapy that limits reperfusion injury in a large animal model of acute myocardial infarction.
Guo, Zhen; Wu, Fei; Singh, Vikramjeet; Guo, Tao; Ren, Xiaohong; Yin, Xianzhen; Shao, Qun; York, Peter; Patterson, Laurence H; Zhang, Jiwen
Cyclodextrins (CD) are widely used bitter taste masking agents, for which the binding equilibrium constant (K) for the drug-CD complex is a conventional parameter for quantitating the taste masking effects. However, some exceptions have been reported to the expected relationship between K and bitterness reduction and the relationship between kinetic parameters of a drug-CD interaction, including association rate constant (K a ) and disassociation rate constant (K d ), and taste masking remains unexplored. In this study, based upon a database of kinetic parameters of drugs-HP-β-CD generated by Surface Plasmon Resonance Imaging for 485 drugs, the host-guest kinetic interactions between drugs and HP-β-CD for prediction of taste masking effects have been investigated. The taste masking effects of HP-β-CD for 13 bitter drugs were quantitatively determined using an electronic gustatory system (α-Astree e-Tongue). Statistical software was used to establish a model based on Euclidean distance measurements, K a and K d of the bitter drugs/HP-β-CD-complexes (R 2 =0.96 and Ptaste masking by HP-β-CD and was successful in predicting the extent of taste masking by HP-β-CD of 44 bitter drugs, which was in accordance with the literature reported. In conclusion, the relationship between kinetics of drug-CD interactions and taste masking was established and providing a new strategy for predicting the cyclodextrin mediated bitter taste masking. Copyright © 2017 Elsevier B.V. All rights reserved.
Spector, Alan C.
Serotonin and the 5HT1A receptor are expressed in a subset of taste receptor cells, and the 5HT3 receptor is expressed on afferent fibers innervating taste buds. Exogenous administration of the selective serotonin reuptake inhibitor, paroxetine, has been shown to increase taste sensitivity to stimuli described by humans as sweet and bitter. Serotonergic agonists also decrease food and fluid intake, and it is possible that modulations of serotonin may alter taste-based hedonic responsiveness; alternatively, or in combination, serotonin may interact with physiological state to impact ingestive behavior. In this study, the unconditioned licking of prototypical taste stimuli by rats in brief-access taste tests was assessed following paroxetine administration (0.3–10 mg/kg intraperitoneal). We also measured sucrose licking by rats in different deprivation states after paroxetine (5 mg/kg). In neither experiment did we find any evidence of an effect of paroxetine on licking relative to water to any of the taste stimuli in the brief-access test at doses that decreased food intake. However, in some conditions, paroxetine decreased trials initiated to tastants. Therefore, a systemic increase in serotonin via paroxetine administration can decrease appetitive behavior in brief-access tests but is insufficient to alter taste-guided consummatory behavior. PMID:21422376
Full Text Available Recently, we reported that calcium-sensing receptor (CaSR is a receptor for kokumi substances, which enhance the intensities of salty, sweet and umami tastes. Furthermore, we found that several γ-glutamyl peptides, which are CaSR agonists, are kokumi substances. In this study, we elucidated the receptor cells for kokumi substances, and their physiological properties. For this purpose, we used Calcium Green-1 loaded mouse taste cells in lingual tissue slices and confocal microscopy. Kokumi substances, applied focally around taste pores, induced an increase in the intracellular Ca(2+ concentration ([Ca(2+](i in a subset of taste cells. These responses were inhibited by pretreatment with the CaSR inhibitor, NPS2143. However, the kokumi substance-induced responses did not require extracellular Ca(2+. CaSR-expressing taste cells are a different subset of cells from the T1R3-expressing umami or sweet taste receptor cells. These observations indicate that CaSR-expressing taste cells are the primary detectors of kokumi substances, and that they are an independent population from the influenced basic taste receptor cells, at least in the case of sweet and umami.
Mojet, J.; Heidema, J.; Christ-Hazelhof, E.
An increase in concentration of one of the tastants in a 'real food' might affect not only the perception of the taste quality of that manipulated tastant but also the other perceivable taste qualities. The influence of concentration increase of sodium or potassium chloride in tomato soup, sucrose
Huisman, Gijs; Bruijnes, Merijn; Heylen, Dirk K.J.
Research into multimodal flavor perceptions has demonstrated associations between basic tastes and visual cues. Moreover, such associations have been found to influence taste perception. Here we are interested in how mixed reality technology in the form of projection mapping can be used to introduce
Diaz, Estrella; De la Casa, L. G.
This paper presents evidence of extinction, spontaneous recovery and renewal in a conditioned preferences paradigm based on taste-taste associations. More specifically, in three experiments rats exposed to a simultaneous compound of citric acid-saccharin solution showed a preference for the citric solution when the preference was measured with a…
Merhav, Maayan; Rosenblum, Kobi
Very little is known about the biological and molecular mechanisms that determine the effect of previous experience on implicit learning tasks. In the present study, we first defined weak and strong taste inputs according to measurements in the behavioral paradigm known as latent inhibition of conditioned taste aversion. We then demonstrated that…
Harington, Kate; Smeele, Rebecca; Van Loon, Fiona; Yuan, Jannie; Haszard, Jillian Joy; Drewer, Amanda; Venn, Bernard Joseph
Added sugars provide calories and desirability to foods and beverages. Our aim was to test whether desire for a sweet taste would be better maintained than a desire for other tastes for 3 hours after a test meal. Eighty-three young adults ate 2 slices of bread on 2 separate occasions after which they were asked to rate their desire for savory, sweet, fatty, or salty tastes and to specify the number of servings of white rice, pizza, cheese and crackers, sweet biscuits, and pasta they could consume. Desirability was assessed using 100-mm visual analog scales (VAS), with 0 mm representing no desire and 100 mm great desire. When participants provided a quantitative assessment of the servings of foods that they wanted to eat following the bread meal, desire decreased on average for all foods measured, χ2 (3) = 2.63, p = 0.452. Mean (95% confidence interval [CI]) change in VAS taste desirability 30 minutes after eating declined for salty (14.5 mm [10.5, 18.6]), fatty (11.2 mm [7.1, 15.2]), and savory (24.1 mm [19.7, 28.5]) tastes (p < 0.001). Desirability for sweet taste did not differ from baseline (2.4 mm [-2.3, 7.1]), and this level of desire was maintained throughout the 3-hour period. The data indicate a partial disconnection between appetite and desirability for sweet taste. Physiological and psychosocial reward systems may make it difficult for people to resist sweet tasting foods and beverages. Targeting familial and cultural practices that discourage the consumption of added sugar foods might be useful to combat desire-driven food intake.
Fujii, Shinsuke; Yavuz, Ahmet; Slone, Jesse; Jagge, Christopher; Song, Xiangyu; Amrein, Hubert
Identification of nutritious compounds is dependent on expression of specific taste receptors in appropriate taste-cell types . In contrast to mammals, which rely on a single, broadly tuned heterodimeric sugar receptor , the Drosophila genome harbors a small subfamily of eight, closely related gustatory receptor (Gr) genes, Gr5a, Gr61a, and Gr64a-Gr64f, of which three have been proposed to mediate sweet taste [3-6]. However, expression and function of several of these putative sugar Gr genes are not known. Here, we present a comprehensive expression and functional analysis using Gr(LEXA/GAL4) alleles that were generated through homologous recombination. We show that sugar Gr genes are expressed in a combinatorial manner to yield at least eight sets of sweet-sensing neurons. Behavioral investigations show that most sugar Gr mutations affect taste responses to only a small number of sugars and that effective detection of most sugars is dependent on more than one Gr gene. Surprisingly, Gr64a, one of three Gr genes previously proposed to play a major role in sweet taste [3, 4], is not expressed in labellar taste neurons, and Gr64a mutant flies exhibit normal sugar responses elicited from the labellum. Our analysis provides a molecular rationale for distinct tuning profiles of sweet taste neurons, and it favors a model whereby all sugar Grs contribute to sweet taste. Furthermore, expression in olfactory organs and the brain implies novel roles for sugar Gr genes in olfaction and internal nutrient sensing, respectively. Thus, sugar receptors may contribute to feeding behavior via multiple sensory systems. Copyright © 2015 Elsevier Ltd. All rights reserved.
Münster, Magdalena; Mohamed-Ahmed, Abeer H A; Immohr, Laura I; Schoch, Corinna; Schmidt, Carsten; Tuleu, Catherine; Breitkreutz, Jörg
The taste of pharmaceuticals strongly affects the compliance of patients. This study investigated the applicability of the electronic tongue and rodent brief-access taste aversion (BATA) model for the bitter compound praziquantel (PZQ) and taste masked liquid formulations for PZQ. In a comparative study maltodextrin (MD) Kleptose ® linecaps 17 was selected as an alternative taste masking agent to two cyclodextrins; hydroxypropyl-beta-cyclodextrin (HP-β-CD) and sulfobutyl ether-beta-cyclodextrin (SBE-β-CD). A phase solubility study showed the highest affinity and solubilization capabilities for SBE-β-CD over HP-β-CD and MD, suggesting the highest taste masking ability for SBE-β-CD. No reliable results were achieved for PZQ with the Insent electronic tongue. Thus this system was not used for further evaluation of solutions with MD and CDs to confirm the results of the solubility study. In contrast the BATA model demonstrated conclusive responses for the aversiveness of PZQ. The concentration of PZQ inhibiting 50% of water lick numbers (called IC 50 value) was 0.06mg/ml. In contrast to the phase solubility study, the MD enabled an equal taste masking effect in vivo in comparison to both CDs. Moreover HP-β-CD showed superior taste masking capabilities for PZQ compared to SBE-β-CD as the SBE-β-CD itself was less acceptable for the rodents than HP-β-CD. In conclusion, the BATA model was identified as a more efficient taste assessment tool for the pure PZQ and liquid formulations in contrast to the electronic tongue and the phase solubility study. Copyright © 2017 Elsevier B.V. All rights reserved.
Lipatova, Olga; Campolattaro, Matthew M.
“Miracle Fruit” is a taste-altering berry that causes sour foods to be perceived as sweet. The present paper describes a laboratory exercise that uses Miracle Fruit to educate students about the sensation and perception of taste. This laboratory exercise reinforces course material pertaining to the function of sweet taste receptors covered in a Sensation and Perception course at Christopher Newport University. Here we provide a step-by-step explanation of the methodology, and an example of data collected and analyzed by one group of students who participated in this laboratory exercise. The origins of the Miracle Fruit, the structure and the physiological function of miraculin (the glycoprotein responsible for the taste-modifying effect found in the pulp of the Miracle Fruit) were discussed before the laboratory exercise. Students then sampled foods known to target different types of tastes (i.e., sweet, sour, bitter and salty) and rated their perception of taste intensity for each food item. Next, students each consumed Miracle Fruit berries, then resampled each original food item and again recorded their perception of taste intensity ratings for these foods. The data confirmed that the sour food items were perceived sweeter after the Miracle Fruit was consumed. The students also completed a written assignment to assess what they learned about the origins, structure, and physiological function of Miracle Fruit. This hands-on laboratory exercise received positive feedback from students. The exercise can be used by other neuroscience educators to teach concepts related to the sensory system of taste. PMID:27980471
Kim, Ki-Suk; Egan, Josephine M.
Aims/hypothesis This study was designed to ascertain whether human enteroendocrine cells express bitter taste receptors, and whether activation of these receptors with bitter-tasting ligands induces secretion of glucagon-like peptide-1 (GLP-1) and peptide YY (PYY). Methods We used human enteroendocrine NCI-H716 cells, isolated duodenal segments from mice, and whole mice as our experimental systems for investigating stimuli and mechanisms underlying GLP-1- and PYY-stimulated release. We measured hormone levels by ELISA and determined bitter taste receptor expression by real-time quantitative PCR. We adopted a pharmacological approach using inhibitors and enhancers of downstream signalling pathways known to be involved in bitter taste transduction in taste bud cells to investigate these pathways in NCI-H716 cells. Results Using a pharmacological approach, we identified signalling pathways triggered by the denatonium benzoate (DB)-activated bitter receptors. This involved activation of α-gustducin (Gαgust)—the specific G-protein subunit that is also present in taste bud cells—reduction of intracellular cAMP levels and enhancement of phospholipase C (PLC) activity, which ultimately led to increased intracellular calcium concentrations and hormone release. Gavage of DB, followed by gavage of glucose, to db/db mice stimulated GLP-1 and subsequent insulin secretion, leading to lower blood glucose levels. Conclusions/interpretation Our study demonstrates that activation of gut-expressed bitter taste receptors stimulates GLP-1 secretion in a PLC-dependent manner. In diabetic mice, DB (a ligand of bitter taste receptor cells), when given via gavage, lowers blood glucose levels in diabetic mice after oral glucose administration, through increased secretion of GLP-1. PMID:25016595
Many studies have demonstrated that chronic exposure to nicotine, one of the main components of tobacco smoke, has profound effects on the functionality of the mammalian taste system. However, the mechanisms underlying nicotine action are poorly understood. In particular no information is available on the chronic effect of nicotine on the functioning of taste cells, the peripheral detectors which transduce food chemicals into electrical signals to the brain. To address this issue, I studied the membrane properties of rat fungiform taste cells and evaluated the effect of long-term exposure to nicotine on the amiloride-sensitive sodium currents (ASSCs). These currents are mediated by the epithelial sodium channels (ENaC) thought to be important, at least in part, in the transduction of salty stimuli. Patch-clamp recording data indicated that ASSCs in taste cells from rats chronically treated with nicotine had a reduced amplitude compared to controls. The pharmacological and biophysical analysis of ASSCs revealed that amplitude reduction was not dependent on changes in amiloride sensitivity or channel ionic permeability, but likely derived from a decrease in the activity of ENaCs. Since these channels are considered to be sodium receptors in taste cells, my results suggest that chronic exposure to nicotine hampers the capability of these cells to respond to sodium ions. This might represent a possible cellular mechanism underlying the reduced taste sensitivity to salt typically found in smokers. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.
Full Text Available The human enteroendocrine L cell line NCI-H716, expressing taste receptors and taste signaling elements, constitutes a unique model for the studies of cellular responses to glucose, appetite regulation, gastrointestinal motility, and insulin secretion. Targeting these gut taste receptors may provide novel treatments for diabetes and obesity. However, NCI-H716 cells are cultured in suspension and tend to form multicellular aggregates, preventing high-throughput calcium imaging due to interferences caused by laborious immobilization and stimulus delivery procedures. Here, we have developed an automated microfluidic platform that is capable of trapping more than 500 single cells into microwells with a loading efficiency of 77% within two minutes, delivering multiple chemical stimuli and performing calcium imaging with enhanced spatial and temporal resolutions when compared to bath perfusion systems. Results revealed the presence of heterogeneity in cellular responses to the type, concentration, and order of applied sweet and bitter stimuli. Sucralose and denatonium benzoate elicited robust increases in the intracellular Ca2+ concentration. However, glucose evoked a rapid elevation of intracellular Ca2+ followed by reduced responses to subsequent glucose stimulation. Using Gymnema sylvestre as a blocking agent for the sweet taste receptor confirmed that different taste receptors were utilized for sweet and bitter tastes. This automated microfluidic platform is cost-effective, easy to fabricate and operate, and may be generally applicable for high-throughput and high-content single-cell analysis and drug screening.
Full Text Available Taste disorder is a rare complication of uvulopalatopharyngoplasty, and may have a significant impact on quality of life. Herein, we report a case of obstructive sleep apnea syndrome in a 51- year-old man who experienced taste disturbance after palatopharyngeal surgery using electrocautery for developing a uvulopalatal flap. Gustatory function test using three-drop-method with solutions of highest concentration was implemented to assess the deficiency of four basic tastes. The results showed deficit of sweet taste associated with phantom of bitter taste. The patient reported constant spontaneous bitter taste and dysgeusia in sweet taste with poor quality of life at the 2-year follow-up. We suggest that patients are informed of the potential for taste impairment from palatopharyngeal surgery, as well as reducing the use of electrocautery in developing uvulopalatal flap to reduce damage to taste function.
Reed, Danielle Renee; Knaapila, Antti
Eating is dangerous. While food contains nutrients and calories that animals need to produce heat and energy, it may also contain harmful parasites, bacteria, or chemicals. To guide food selection, the senses of taste and smell have evolved to alert us to the bitter taste of poisons and the sour taste and off-putting smell of spoiled foods. These sensory systems help people and animals to eat defensively, and they provide the brake that helps them avoid ingesting foods that are harmful. But choices about which foods to eat are motivated by more than avoiding the bad; they are also motivated by seeking the good, such as fat and sugar. However, just as not everyone is equally capable of sensing toxins in food, not everyone is equally enthusiastic about consuming high-fat, high-sugar foods. Genetic studies in humans and experimental animals strongly suggest that the liking of sugar and fat is influenced by genotype; likewise, the abilities to detect bitterness and the malodors of rotting food are highly variable among individuals. Understanding the exact genes and genetic differences that affect food intake may provide important clues in obesity treatment by allowing caregivers to tailor dietary recommendations to the chemosensory landscape of each person. PMID:21036327
Ohnuki, Mari; Shinada, Kayoko; Ueno, Masayuki; Zaitsu, Takashi; Wright, Fredrick Allan Clive; Kawaguchi, Yoko
The main objective of this study was to investigate the prevalence of taste hyposensitivity and the relationships between sex, oral health status, and eating habits with taste hyposensitivity in Japanese senior high school students. Oral examinations, sweet and salt whole-mouth taste tests, and a questionnaire about eating habits were conducted on 234 senior high school students. Factors affecting taste hyposensitivity were investigated using a multivariate analysis. Sweet-taste hyposensitivity was observed in 7.3% of the students, and salt-taste hyposensitivity in 22.2%. Approximately 3% of the students had both sweet- and salt-taste hyposensitivity, and 22.6% had either sweet- or salt-taste hyposensitivity. In total, 26% had a taste hyposensitivity. There were significant relationships between the intake of instant noodles with sweet-taste hyposensitivity, and the intake of vegetables or isotonic drinks with salt-taste hyposensitivity. There was a significant association between eating habits and taste hyposensitivity in Japanese senior high school students. Taste tests would be a helpful adjunct for students to recognize variations in taste sensitivity, and a questionnaire about their eating habits might provide an effective self-review of their eating habits, and therefore, provide motivation to change. © 2011 Blackwell Publishing Asia Pty Ltd.
Reinoso Carvalho, Felipe; Van Ee, Raymond; Rychtarikova, Monika; Touhafi, Abdellah; Steenhaut, Kris; Persoone, Dominique; Spence, Charles
The soundscapes of those places where we eat and drink can influence our perception of taste. Here, we investigated whether contextual sound would enhance the subjective value of a tasting experience. The customers in a chocolate shop were invited to take part in an experiment in which they had to evaluate a chocolate's taste while listening to an auditory stimulus. Four different conditions were presented in a between-participants design. Envisioning a more ecological approach, a pre-recorded piece of popular music and the shop's own soundscape were used as the sonic stimuli. The results revealed that not only did the customers report having a significantly better tasting experience when the sounds were presented as part of the food's identity, but they were also willing to pay significantly more for the experience. The method outlined here paves a new approach to dealing with the design of multisensory tasting experiences, and gastronomic situations.
Rodríguez-García, Gabriela; Miranda, María Isabel
Acetylcholine (ACh) is thought to facilitate cortical plasticity during memory formation and its release is regulated by the nucleus basalis magnocellularis (NBM). Questions remain regarding which neuronal circuits and neurotransmitters trigger activation or suppression of cortical cholinergic activity. During novel, but not familiar, taste consumption, there is a significant increase in ACh release in the insular cortex (IC), a highly relevant structure for taste learning. Here, we evaluate how GABA inhibition modulates cholinergic transmission and its involvement during taste novelty processing and familiar taste memory retrieval. Using saccharin as a taste stimulus in a taste preference paradigm, we examined the effects of injecting the GABAA receptor agonist muscimol or the GABAA receptor antagonist bicuculline into the IC or NBM during learning or retrieval of an appetitive taste memory on taste preference in male Sprague Dawley rats. GABAA receptor agonism and antagonism had opposite effects on cortical ACh levels in novel taste presentation versus familiar taste recognition and ACh levels were associated with the propensity to acquire or retrieve a taste memory. These results indicate that the pattern of cortical cholinergic and GABAergic neuroactivity during novel taste exposure is the opposite of that which occurs during familiar taste recognition and these differing neurotransmitter system states may enable different behavioral consequences. Divergences in ACh and GABA levels may produce differential alterations in excitatory and inhibitory neural processes within the cortex during acquisition and retrieval. During learning and recall, several brain structures act together. This work demonstrates interactions between cortical cholinergic and GABAergic systems during taste learning and memory retrieval. We found that the neuroactivity pattern during novel taste exposure is opposite that which occurs during familiar taste recognition. GABAA receptors must
Akinori Inamura, MD
Conclusion: Our study encourages utilizing longitudinal and cross-individual ultrasound studies within and amongst individuals of different ages to allow understanding the variations of the vagal nerve in its neck portion. This has implications to many neurosurgical procedures.
Lapis, Trina J; Penner, Michael H; Lim, Juyun
The sense of taste is essential for identifying potential nutrients and poisons. Accordingly, specialized taste receptor cells are activated by food-derived chemicals. Because of its importance in the human diet, oral detection of starch, or its degradation products, would presumably be highly beneficial. Yet, it has long been assumed that simple sugars are the only class of carbohydrates that humans can taste. There is, however, considerable evidence that rodents can taste starch degradation products (i.e., glucose polymers composed of maltooligosaccharides with 3-10 glucose units and maltopolysaccharides with >10 glucose units) and that their detection is independent of the sweet taste receptor, T1R2/T1R3. The present study was designed 1) to measure individual differences in human taste perception of glucose polymers, 2) to understand individual differences in the activity of salivary α-amylase, and 3) to investigate the role that salivary α-amylase may play in the taste perception of glucose polymers. In the first experiment, subjects rated taste intensity of glucose, sucrose, NaCl, and glucose polymers of various chain lengths, while their noses were clamped. Saliva samples from the subjects were also collected and their salivary α-amylase activity was assayed. Results showed that the perceived intensities of glucose, sucrose, and NaCl were significantly correlated (r = 0.75-0.85, P glucose polymers, whereas intensity ratings of all glucose polymers were highly correlated with one another (r = 0.69-0.82, P glucose polymers did not significantly differ between individuals with high and low α-amylase activity. A follow up experiment was conducted to quantify the concentrations of glucose and maltose that were inherently present in the glucose polymer stimuli and to determine whether the amounts were within a perceptually detectable range. Results revealed that the amounts of simple sugars present in the test stimuli were trivial and were mostly at an
Full Text Available The sense of taste is among the regulatory mechanism for acceptance or rejection of foods. In oral submucous fibrosis (OSMF patients, impairment of taste sensation has not received much attention, owing to limited research work in the field. This study was conducted to analyze the taste impairment in OSMF patients by using four basic tastes: Sweet, sour, salty and bitter, among a group of 30 subjects by using physiological taste stimuli tastants. In OSMF, significant taste alteration was found with sweet followed by salt, bitter and sour.
Ichimura, Sayaka; Nakamura, Yukinobu; Yoshida, Yuka; Hattori, Akihito
We evaluated the enhancement of cured meat taste during maturation by sensory analysis. We focused on the heat-stable sarcoplasmic fraction (HSSF) to identify the factors related to cured meat taste. Because the dry matter of HSSF contained more than 30% nitrogen, nitrogen compounds such as free amino acids, small peptides and adenosine triphosphate-related compounds seemed to be the important components of HSSF. The samples cured with HSSF for 2 h exhibited the same taste profile as ones cured without HSSF for 168 h. Therefore, the changes in the amount and fractions of nitrogen compounds were examined in HSSF during incubation from 0 to 168 h. The concentration of hypoxanthine (Hx) gradually increased, while inosine-5'-monophosphate decreased during the incubation. The samples cured with pickles containing various concentrations of Hx were subjected to sensory analysis. The addition of Hx, in a dose-dependent fashion, enhanced cured meat taste by maturation for 2 h. It was concluded that Hx is essential for the enhancement of cured meat taste. © 2016 The Authors. Animal Science Journal published by John Wiley & Sons Australia, Ltd on behalf of Japanese Society of Animal Science.
Umami is a basic tastes, along with sweet, salty, bitter and sour, which is imparted by glutamate, one of the free amino acids in foods. Since its discovery of umami by a Japanese scientist in 1908, umami is now perceived globally a basic taste. Recent collaboration among chefs and researchers on traditional soup stocks showed a difference in taste profiles of Japanese soup stock 'dashi' and Western style soup stock. The free amino acids profile's in dashi and soup stock showed how Japanese have traditionally adopted a simple umami taste. The exchange of knowledge on cooking methods and diverse types of umami rich foods in different countries displays the blending of the culinary arts, food science and technology for healthy and tasty solutions. Since Japanese cuisine 'WASHOKU' was listed in the 'Intangible Heritage of UNESCO' in 2013, many people in the world now have great interest in Japanese cuisine. One of the unique characteristics of this cuisine is that 'dashi' is an indispensable material for cooking a variety of Japanese dishes. Many chefs from Europe, US and South America have come to Japan to learn Japanese cuisine in the last 10 years, and umami has become recognized as a common taste worldwide. Researchers and culinary professionals have begun to pay attention to the traditional seasonings and condiments rich in glutamate available throughout the world.
Nakamura, Yukinobu; Yoshida, Yuka; Hattori, Akihito
Abstract We evaluated the enhancement of cured meat taste during maturation by sensory analysis. We focused on the heat‐stable sarcoplasmic fraction (HSSF) to identify the factors related to cured meat taste. Because the dry matter of HSSF contained more than 30% nitrogen, nitrogen compounds such as free amino acids, small peptides and adenosine triphosphate‐related compounds seemed to be the important components of HSSF. The samples cured with HSSF for 2 h exhibited the same taste profile as ones cured without HSSF for 168 h. Therefore, the changes in the amount and fractions of nitrogen compounds were examined in HSSF during incubation from 0 to 168 h. The concentration of hypoxanthine (Hx) gradually increased, while inosine‐5′‐monophosphate decreased during the incubation. The samples cured with pickles containing various concentrations of Hx were subjected to sensory analysis. The addition of Hx, in a dose‐dependent fashion, enhanced cured meat taste by maturation for 2 h. It was concluded that Hx is essential for the enhancement of cured meat taste. PMID:27169902
Sturge-Apple, Melissa L.; Suor, Jennifer H.; Davies, Patrick T.; Cicchetti, Dante; Skibo, Michael A.; Rogosch, Fred A.
Socioeconomic disparities in children���s delay of gratification exist, with impoverished children displaying greater difficulties in this developmental domain. The present paper examined the role of vagal tone in predicting the ability to delay gratification across resource rich and resource poor environments. Embedding hypotheses within evolutionary models of children���s conditional adaptation to proximal rearing contexts, Study 1 tested whether elevated vagal tone was associated with lowe...
Rosenberg, Tali; Elkobi, Alina; Rosenblum, Kobi
Regulation of protein degradation via the ubiquitin proteasome system is crucial for normal learning and synaptic plasticity processes. While some studies reveal that increased proteasome degradation is necessary for different types of learning, others suggest the proteasome to be a negative regulator of plasticity. We aim to understand the molecular and cellular processes taking place in the gustatory cortex (GC), which underlie appetitive and aversive forms of taste learning. Previously, we have shown that N-methyl d-aspartic acid receptor (NMDAR)-dependent upregulation of proteasome activity 4h after novel taste learning is necessary for the association of novel taste with malaise and formation of conditioned taste aversion (CTA). Here, we first identify a correlative increase in proteasome activity in the GC immediately after novel taste learning and study the upstream and downstream effectors of this modulated proteasome activity. Interestingly, proteasome-mediated degradation was reduced in the GC, 20min after novel taste consumption in a muscarinic acetylcholine receptor (mAChR)-dependent and NMDAR-independent manner. This reduction in protein degradation led to an increased amount of p70 S6 kinase (p70S6k), which was abolished in the presence of mAChR antagonist scopolamine. Infusion of lactacystin, a proteasome inhibitor, to the GC precluded the amnestic effect of scopolamine. This study shows for the first time that following novel taste learning there is a cortical, mAChR-dependent reduced proteasome activity that enables the memory of taste familiarity. Moreover, inhibition of degradation in the GC attenuates novel taste learning and of p70 S6 kinase correlative increased expression. These results shed light on the complex regulation of protein synthesis and degradation machineries in the cortex following novel taste experience. Copyright © 2016 Elsevier Inc. All rights reserved.
Full Text Available Abstract In recent years, diverse scholars have addressed the issue of the chemosensory perceptions associated with traditional medicines, nevertheless there is still a distinct lack of studies grounded in the social sciences and conducted from a cross-cultural, comparative perspective. In this urban ethnobotanical field study, 254 informants belonging to the Gujarati, Kashmiri and English ethnic groups and living in Western Yorkshire in Northern England were interviewed about the relationship between taste and medicinal perceptions of five herbal drugs, which were selected during a preliminary study. The herbal drugs included cinnamon (the dried bark of Cinnamomum verum, Lauraceae, mint (the leaves of Mentha spp., Lamiaceae, garlic (the bulbs of Allium sativum, Alliaceae, ginger (the rhizome of Zingiber officinale, Zingiberaceae, and cloves (the dried flower buds of Syzygium aromaticum, Myrtaceae. The main cross-cultural differences in taste perceptions regarded the perception the perception of the spicy taste of ginger, garlic, and cinnamon, of the bitter taste of ginger, the sweet taste of mint, and of the sour taste of garlic. The part of the study of how the five selected herbal drugs are perceived medicinally showed that TK (Traditional Knowledge is widespread among Kashmiris, but not so prevalent among the Gujarati and especially the English samples. Among Kashmiris, ginger was frequently considered to be helpful for healing infections and muscular-skeletal and digestive disorders, mint was chosen for healing digestive and respiratory troubles, garlic for blood system disorders, and cinnamon was perceived to be efficacious for infectious diseases. Among the Gujarati and Kashmiri groups there was evidence of a strong link between the bitter and spicy tastes of ginger, garlic, cloves, and cinnamon and their perceived medicinal properties, whereas there was a far less obvious link between the sweet taste of mint and cinnamon and their
Pieroni, Andrea; Torry, Bren
In recent years, diverse scholars have addressed the issue of the chemosensory perceptions associated with traditional medicines, nevertheless there is still a distinct lack of studies grounded in the social sciences and conducted from a cross-cultural, comparative perspective. In this urban ethnobotanical field study, 254 informants belonging to the Gujarati, Kashmiri and English ethnic groups and living in Western Yorkshire in Northern England were interviewed about the relationship between taste and medicinal perceptions of five herbal drugs, which were selected during a preliminary study. The herbal drugs included cinnamon (the dried bark of Cinnamomum verum, Lauraceae), mint (the leaves of Mentha spp., Lamiaceae), garlic (the bulbs of Allium sativum, Alliaceae), ginger (the rhizome of Zingiber officinale, Zingiberaceae), and cloves (the dried flower buds of Syzygium aromaticum, Myrtaceae). The main cross-cultural differences in taste perceptions regarded the perception the perception of the spicy taste of ginger, garlic, and cinnamon, of the bitter taste of ginger, the sweet taste of mint, and of the sour taste of garlic. The part of the study of how the five selected herbal drugs are perceived medicinally showed that TK (Traditional Knowledge) is widespread among Kashmiris, but not so prevalent among the Gujarati and especially the English samples. Among Kashmiris, ginger was frequently considered to be helpful for healing infections and muscular-skeletal and digestive disorders, mint was chosen for healing digestive and respiratory troubles, garlic for blood system disorders, and cinnamon was perceived to be efficacious for infectious diseases. Among the Gujarati and Kashmiri groups there was evidence of a strong link between the bitter and spicy tastes of ginger, garlic, cloves, and cinnamon and their perceived medicinal properties, whereas there was a far less obvious link between the sweet taste of mint and cinnamon and their perceived medicinal
Guiraud, Thibaut; Labrunee, Marc; Gaucher-Cazalis, Kevin; Despas, Fabien; Meyer, Philippe; Bosquet, Laurent; Gales, Celine; Vaccaro, Angelica; Bousquet, Marc; Galinier, Michel; Sénard, Jean-Michel; Pathak, Atul
Autonomic dysfunction including sympathetic activation and vagal withdrawal has been reported in patients with chronic heart failure (CHF). We tested the hypotheses that high-intensity interval exercise (HIIE) in CHF patients would enhance vagal modulation and thus decrease arrhythmic events. Eighteen CHF patients underwent a baseline assessment (CON) and were then randomized to a single session of HIIE and to an isocaloric moderate-intensity continuous exercise (MICE). We evaluated the HR, HR variability parameters, and arrhythmic events by 24-h Holter ECG recordings after HIIE, MICE, and CON sessions. We found that HR was significantly decreased after HIIE (68 ± 3 bpm, P CHF patients, leading to significant reductions of HR and arrhythmic events in a 24-h posttraining period. Cardioprotective effects of HIIE in CHF patients need to be confirmed in a larger study population and on a long-term basis.
Trolle, Christian; Mortensen, Kristian Havmand; Andersen, Niels Holmark
examined once. Aortic dimensions were measured at nine positions using 3D, non-contrast and free-breathing cardiovascular-MRI. HRV measured by short-term spectral analysis (supine-standing), transthoracic echocardiography, 24-hour ambulatory BP were done. Results: The changes in High frequency (HF) power......-average=-0.312 and -0.341; pmeasures of HRV. Prospectively there were no changes in HRV. Conclusions: A perturbed sympatho-vagal balance is present in TS explained by a decreased vagal activity......Objective: The risk of aortic dissection is 100 fold increased in Turner syndrome (TS). Increased blood pressure (BP) and heart rate is present as well as an increased risk of ischemic heart disease and diabetes. This study aimed to prospectively assess heart rate variability (HRV) in TS and its...
Azam, Muhammad Abid; Ritvo, Paul; Fashler, Samantha R; Katz, Joel
The present study examined relationships among gaze behaviour and cardiac vagal tone using a novel stress-inducing task. Participants' (N = 40) eye movements and heart rate variability (HRV) were measured during an unsolvable computer-based task randomly presenting feedback of "Right" and "Wrong" answers distinctly onscreen after each trial. Subgroups were created on the basis of more frequent eye movements to the right ("Correct"-Attenders; n = 23) or wrong ("Incorrect"-Attenders; n = 17) areas onscreen. Correct-Attenders maintained HRV from baseline to the stress task. In contrast, Incorrect-Attenders spent significantly more time viewing "Wrong" feedback, exhibited a reduction in HRV during the stress condition (p attention to negative feedback ("Wrong") elicits perseverative stress and negative self-evaluations among university students. This study highlights the potential for studying attentional biases and emotional distress through combined measures of gaze behaviour and cardiac vagal tone.
Holochwost, Steven J; Gariépy, Jean-Louis; Propper, Cathi B; Mills-Koonce, W Roger; Moore, Ginger A
The authors investigated the relationships among parenting behaviors, infant vagal tone, and subsequent attachment classification. Vagal tone was assessed among 6-month olds (n = 95) during the still-face paradigm (SFP) via respiratory sinus arrhythmia (RSA), while attachment security and disorganization were measured at 12 months during the strange situation procedure (SSP). Infants demonstrating higher levels of RSA during the normal interaction and reunion episodes of the SFP whose mothers were also rated as negative-intrusive exhibited higher levels of attachment disorganization at 12 months, while infants with lower RSA and mothers who were negative-intrusive did not exhibit higher levels of disorganization. These results suggest that high levels of RSA may not be adaptive within the context of negative-intrusive parenting. © 2014 Wiley Periodicals, Inc.
Full Text Available Vertebrates can perceive at least five different taste qualities, each of which is thought to have a specific role in the evolution of different species. The avoidance of potentially poisonous foods, which are generally bitter or sour tasting, and the search for more nutritious ones, those with high-fat and high-sugar content, are two of the most well-known examples. The study of taste genes encoding receptors that recognize ligands triggering taste sensations has helped to reconstruct several evolutionary adaptations to dietary changes. In addition, an increasing number of studies have focused on pseudogenes, genomic DNA sequences that have traditionally been considered defunct relatives of functional genes mostly because of the presence of deleterious mutations interrupting their open reading frames. The study of taste receptor pseudogenes has helped to shed light on how the evolutionary history of taste in vertebrates has been the result of a succession of gene gain and loss processes. This dynamic role in evolution has been explained by the “less-is-more” hypothesis, suggesting gene loss as a mechanism of evolutionary change in response to a dietary shift. This mini-review aims at depicting the major lineage-specific loss of function of taste receptor genes in vertebrates, stressing their evolutionary importance and recapitulating signatures of natural selection and their correlations with food habits.
Antinucci, Marco; Risso, Davide
Vertebrates can perceive at least five different taste qualities, each of which is thought to have a specific role in the evolution of different species. The avoidance of potentially poisonous foods, which are generally bitter or sour tasting, and the search for more nutritious ones, those with high-fat and high-sugar content, are two of the most well-known examples. The study of taste genes encoding receptors that recognize ligands triggering taste sensations has helped to reconstruct several evolutionary adaptations to dietary changes. In addition, an increasing number of studies have focused on pseudogenes, genomic DNA sequences that have traditionally been considered defunct relatives of functional genes mostly because of the presence of deleterious mutations interrupting their open reading frames. The study of taste receptor pseudogenes has helped to shed light on how the evolutionary history of taste in vertebrates has been the result of a succession of gene gain and loss processes. This dynamic role in evolution has been explained by the “less-is-more” hypothesis, suggesting gene loss as a mechanism of evolutionary change in response to a dietary shift. This mini-review aims at depicting the major lineage-specific loss of function of taste receptor genes in vertebrates, stressing their evolutionary importance and recapitulating signatures of natural selection and their correlations with food habits. PMID:29234667
Lang, Ivan M.; Medda, Bidyut K.; Shaker, Reza
Esophageal mechanorecptors, i.e. muscular slowly adapting tension receptors and mucosal rapidly adapting touch receptors, mediate different sets of reflexes. The aim of this study was to determine the medullary vagal nuclei involved in the reflex responses to activation of these receptors. Thirty-three cats were anesthetized with alpha-chloralose and the esophagus was stimulated by slow balloon or rapid air distension. The physiological effects of the stimuli (N=4) were identified by recordin...
Shams, H; Daffonchio, L; Scheid, P
1. Levodropropizine (LVDP) is an effective antitussive drug. Its effects on single-unit discharge of vagal afferent C-fibres were tested in anaesthetized cats to assess whether an inhibition of vagal C-fibres is involved in its antitussive properties. Vagal C-fibres, identified by their response to phenylbiguanide (PBG), were recorded via suction electrodes from the distal part of the cut vagus. Based on their response to lung inflation, C-fibres were classified as pulmonary (19 fibres) or non-pulmonary (6 fibres). 2. PBG increased the discharge rate of both C-fibre types and activated a respiratory reflex causing apnoea. This reflex was abolished when the second vagus nerve was cut as well, while PBG-mediated stimulation of the C-fibres was not affected by vagotomy. 3. LVDP was administered intravenously and the C-fibre response to PBG was compared with that before administration of the drug. LVDP reduced both the duration of apnoea and the response of the C-fibre to PBG. 4. Comparison of the C-fibre responses to PBG and to a mixture of PBG and LVDP revealed that the period of apnoea was shortened and the discharge rate of the C-fibre reduced when LVDP was present. 5. The LVDP-induced inhibition of the C-fibre response to PBG was on average 50% in pulmonary and 25% in non-pulmonary fibres. 6. These results suggest that LVDP significantly reduces the response of vagal C-fibres to chemical stimuli. It is, thus, likely that the antitussive effect of LVDP is mediated through its inhibitory action on C-fibres.
Yu, Xiaoyun; Hu, Youtian; Yu, Shaoyong
Acid reflux-induced heartburn and noncardiac chest pain are processed peripherally by sensory nerve endings in the wall of the esophagus, but the underlying mechanism is still unclear. This study aims to determine the effects of acid on esophageal vagal nociceptive afferent subtypes. Extracellular single-unit recordings were performed in guinea pig vagal nodose or jugular C fiber neurons by using ex vivo esophageal-vagal preparations with intact nerve endings in the esophagus. We recorded action potentials (AP) of esophageal nodose or jugular C fibers evoked by acid perfusion and compared esophageal distension-evoked AP before and after acid perfusion. Acid perfusion for 30 min (pH range 7.4 to 5.8) did not evoke AP in nodose C fibers but significantly decreased their responses to esophageal distension, which could be recovered after washing out acid for 90 min. In jugular C fibers, acid perfusion not only evoked AP but also inhibited their responses to esophageal distension, which were not recovered after washing out acid for 120 min. Lower concentration of capsaicin perfusion mimicked acid-induced effects in nodose and jugular C fibers. Pretreatment with TRPV1 antagonist AMG9810, but not acid-sensing ion channel (ASIC) inhibitor amiloride, significantly inhibited acid-induced effects in nodose and jugular C fiber. These results demonstrate that esophageal vagal nociceptive afferent nerve subtypes display distinctive responses to acid. Acid activates jugular, but not nodose, C fibers and inhibits both of their responses to esophageal distension. These effects are mediated mainly through TRPV1. This inhibitory effect is a novel finding and may contribute to esophageal sensory/motor dysfunction in acid reflux diseases. Copyright © 2014 the American Physiological Society.
Lang, Justin A R; Pearson, James T; Binder-Heschl, Corinna; Wallace, Megan J; Siew, Melissa L; Kitchen, Marcus J; Te Pas, Arjan B; Lewis, Robert A; Polglase, Graeme R; Shirai, Mikiyasu; Hooper, Stuart B
Lung aeration at birth significantly increases pulmonary blood flow, which is unrelated to increased oxygenation or other spatial relationships that match ventilation to perfusion. Using simultaneous X-ray imaging and angiography in near-term rabbits, we investigated the relative contributions of the vagus nerve and oxygenation to the increase in pulmonary blood flow at birth. Vagal denervation inhibited the global increase in pulmonary blood flow induced by partial lung aeration, although high inspired oxygen concentrations can partially mitigate this effect. The results of the present study indicate that a vagal reflex may mediate a rapid global increase in pulmonary blood flow in response to partial lung aeration. Air entry into the lungs at birth triggers major cardiovascular changes, including a large increase in pulmonary blood flow (PBF) that is not spatially related to regional lung aeration. To investigate the possible underlying role of a vagally-mediated stimulus, we used simultaneous phase-contrast X-ray imaging and angiography in near-term (30 days of gestation) vagotomized (n = 15) or sham-operated (n = 15) rabbit kittens. Rabbits were imaged before ventilation, when one lung was ventilated (unilateral) with 100% nitrogen (N2 ), air or 100% oxygen (O2 ), and after all kittens were switched to unilateral ventilation in air and then ventilation of both lungs using air. Compared to control kittens, vagotomized kittens had little or no increase in PBF in both lungs following unilateral ventilation when ventilation occurred with 100% N2 or with air. However, relative PBF did increase in vagotomized animals ventilated with 100% O2 , indicating the independent stimulatory effects of local oxygen concentration and autonomic innervation on the changes in PBF at birth. These findings demonstrate that vagal denervation inhibits the previously observed increase in PBF with partial lung aeration, although high inspired oxygen concentrations can partially
Spangler, Derek P
Anxiety is marked by impaired inhibition of distraction (Eysenck et al., 2007). It is unclear whether these impairments are reduced or exacerbated when loading working memory (WM) with non-affective information. Cardiac vagal control has been related to emotion regulation and may serve as a proxy for load-related inhibition under anxiety (Thayer and Lane, 2009). The present study examined whether: (1) the enhancing and impairing effects of load on inhibition exist together in a nonlinear func...
Jiang, Peihua; Josue, Jesusa; Li, Xia; Glaser, Dieter; Li, Weihua; Brand, Joseph G; Margolskee, Robert F; Reed, Danielle R; Beauchamp, Gary K
Mammalian sweet taste is primarily mediated by the type 1 taste receptor Tas1r2/Tas1r3, whereas Tas1r1/Tas1r3 act as the principal umami taste receptor. Bitter taste is mediated by a different group of G protein-coupled receptors, the Tas2rs, numbering 3 to ∼66, depending on the species. We showed previously that the behavioral indifference of cats toward sweet-tasting compounds can be explained by the pseudogenization of the Tas1r2 gene, which encodes the Tas1r2 receptor. To examine the generality of this finding, we sequenced the entire coding region of Tas1r2 from 12 species in the order Carnivora. Seven of these nonfeline species, all of which are exclusive meat eaters, also have independently pseudogenized Tas1r2 caused by ORF-disrupting mutations. Fittingly, the purifying selection pressure is markedly relaxed in these species with a pseudogenized Tas1r2. In behavioral tests, the Asian otter (defective Tas1r2) showed no preference for sweet compounds, but the spectacled bear (intact Tas1r2) did. In addition to the inactivation of Tas1r2, we found that sea lion Tas1r1 and Tas1r3 are also pseudogenized, consistent with their unique feeding behavior, which entails swallowing food whole without chewing. The extensive loss of Tas1r receptor function is not restricted to the sea lion: the bottlenose dolphin, which evolved independently from the sea lion but displays similar feeding behavior, also has all three Tas1rs inactivated, and may also lack functional bitter receptors. These data provide strong support for the view that loss of taste receptor function in mammals is widespread and directly related to feeding specializations.
Zafra, María A; Molina, Filomena; Puerto, Amadeo
The aim of this study was to investigate the biological process by which animals regulate meal size. An experimental procedure for its study is to examine food re-intake after partial withdrawal of gastric food contents. The aim of the present experiments was to investigate the role of vagal afferents in food re-intake after perivagal administration of capsaicin, a neurotoxin that specifically damages weakly myelinated or unmyelinated vagal sensory axons. In experiment 1, capsaicin-treated animals initially consumed higher amounts of food in comparison to controls (in first 24 hours) but their excess intake was compensated for in subsequent daily satiation tests. However, capsaicin treatment impaired the common short-term re-intake behavior observed in control rats after partial removal of gastric food nutrients, and the lesioned animals consumed significantly less food than had been withdrawn after completion of the initial meal; moreover, in this deficit condition, no counteraction was observed in subsequent repeated tests. This behavioral disturbance cannot be attributed to an indirect effect of capsaicin on gastric emptying volume, because the stomach contents were similar in both groups (Experiment 2). These findings are discussed in terms of the critical role played by vagal afferents in rapid visceral adjustments related to short-term food intake, as also observed in other gastrointestinal regulatory behaviors that require immediate processing of visceral sensory information.
Cooper, Timothy M; McKinley, Paula S; Seeman, Teresa E; Choo, Tse-Hwei; Lee, Seonjoo; Sloan, Richard P
Evidence from numerous animal models shows that vagal activity regulates inflammatory responses by decreasing cytokine release. Heart rate variability (HRV) is a reliable index of cardiac vagal regulation and should be inversely related to levels of inflammatory markers. Inflammation is also regulated by sympathetic inputs, but only one previous paper controlled for this. In a larger and more representative sample, we sought to replicate those results and examine potential sex differences in the relationship between HRV and inflammatory markers. Using data from the MIDUS II study, we analyzed the relationship between 6 inflammatory markers and both HF-HRV and LF-HRV. After controlling for sympathetic effects measured by urinary norepinephrine as well as a host of other factors, LF-HRV was found to be inversely associated with fibrinogen, CRP and IL-6, while HF-HRV was inversely associated with fibrinogen and CRP. We did not observe consistent sex differences. These results support the existence of the vagal anti-inflammatory pathway and suggest that it has similar effects in men and women. Copyright © 2014 Elsevier Inc. All rights reserved.
Full Text Available A 70-year-old female presented with a neck mass and sporadic dry cough, often leading to fits of coughing severe enough to cause vomiting. The patient reported that touching the mass triggered the cough. On examination, a 2.5 cm right-sided level two neck mass deep to the sternocleidomastoid was present. Palpation of the mass immediately triggered coughing. Cross-sectional imaging proposed vagal paraganglioma as the chief differential, which was confirmed following surgical excision. The patient reported complete resolution of her severe dry cough after surgery. Vagal paragangliomas are rare neuroendocrine tumors arising from the neural crest-derived paraganglionic tissue surrounding the vagus nerve, typically presenting as a neck mass associated with hoarseness or pulsatile tinnitus. To the best of our knowledge this is a unique description in the English literature. This case is presented to aid physicians should they encounter a neck mass associated with cough. Vagal paraganglioma, although rare, should be part of the differential in such a presentation.
Wistoft, Karen; Leer, Jonatan
problems is often used to legitimate extremely normative food education for children and control mechanism such as nudging, shaming and self-policing. In this paper, we want to focus on how taste is used in contemporary food education. We will do this by critically discussing a series of academic studies...... and not as an important sense, a source to pleasure, or a central way of sensually understanding and approaching the world. In other words, taste literacy becomes a tool to push children towards ‘hegemonic nutrition’. Theoretically, the paper is inspired by the reworking of Foucault’s governmentality concept in recent...
Full Text Available ED Toffanello,1 EM Inelmen,1 A Imoscopi,1 E Perissinotto,2 A Coin,1 F Miotto,1 LM Donini,3 D Cucinotta,4 M Barbagallo,5 E Manzato,1 G Sergi11Department of Medical and Surgical Sciences, Geriatrics Division and University of Padova, Padova, 2Department of Environmental Medicine and Public Health, University of Padua, Padua, Italy; 3Department of Medical Physiopathology (Food Science Section, University of Roma, La Sapienza, Roma, 4S Orsola Malpighi Hospital, Bologna, 5Geriatric Unit, Department of Internal Medicine and Emerging Diseases, University of Palermo, Palermo, ItalyBackground: Loss of the sense of taste is common among older people. Morbidities and polypharmacy may contribute to the age-related decline in gustatory function. The aims of the present study were to investigate taste perception in elderly hospitalized patients by comparing their taste recognition thresholds with those of healthy, free-living elderly individuals and to identify potential determinants of taste loss.Methods: The participants in this observational study were 55 elderly patients hospitalized in the acute geriatric section of the Department of Medical and Surgical Sciences at Padova University and 41 free-living individuals aged older than 65 years, randomly recruited from elderly people attending mild fitness programs at public gymnasiums in Padova. Data were collected on nutrition, health, cognitive, and functional status for all participants. Gustatory capabilities were assessed using aqueous solutions of sucrose, sodium chloride, citric acid, and quinine hydrochloride (representing sweet, salty, sour, and bitter stimuli, respectively, and taste recognition thresholds were measured in both groups.Results: In comparison with the free-living elderly subjects, those in hospital were significantly less able to recognize the taste of citric acid (P < 0.05. Low citric acid sensitivity was independently associated with advanced age (≥75 years; odds ratio [OR] 3
Passilly-Degrace, Patricia; Chevrot, Michael; Bernard, Arnaud; Ancel, Déborah; Martin, Céline; Besnard, Philippe
Over the last decade, converging data have been accumulated both in rodents and humans, supporting the existence of a sixth taste modality devoted to the perception of dietary lipids. It is well known that the sense of taste is determinant for the food choice and that the overconsumption of highly palatable energy-dense foods contributes to the current obesity epidemic. Thus, an important issue in terms of Public Health is to understand the mechanisms by which the oro-sensory perception of fat is regulated. An overview of our current knowledge in this field of investigations is proposed in this mini-review. Copyright © 2013 Elsevier Masson SAS. All rights reserved.
Ijpma, I.; Renken, R. J.; ter Horst, G. J.; Reyners, A. K. L.
Background: Metallic taste is a taste alteration frequently reported by cancer patients treated with chemotherapy. Attention to this side effect of chemotherapy is limited. This review addresses the definition, assessment methods, prevalence, duration, etiology, and management strategies of metallic
Brock, C; Jessen, N. C.; Brock, Birgitte
in people with Type 1 diabetes than in a matched healthy cohort and lower still in people with established neuropathy. METHODS: Cardiac vagal tone is a validated cardiometrically derived index of parasympathetic tone. It is measured using a standard three-lead electrocardiogram which connects, via Bluetooth......, to a smartphone application. A 5-min resting recording of cardiac vagal tone was undertaken and observational comparisons were made between 42 people with Type 1 diabetes and peripheral neuropathy and 23 without peripheral neuropathy and 65 healthy people. In those with neuropathy, 24-h heart rate variability...... values were compared with cardiac vagal tone. Correlations between cardiac vagal tone and clinical variables were also made. RESULTS: Cardiac vagal tone was lower in people with established neuropathy and Type 1 diabetes in comparison with healthy participants [median (interquartile range) linear vagal...
Filogonio, Renato; Wang, Tobias; Taylor, Edwin W; Abe, Augusto S; Leite, Cléo A C
The undivided ventricle of non-crocodilian reptiles allows for intracardiac admixture of oxygen-poor and oxygen-rich blood returning via the atria from the systemic circuit and the lungs. The distribution of blood flow between the systemic and pulmonary circuits may vary, based on differences between systemic and pulmonary vascular conductances. The South American rattlesnake, Crotalus durissus, has a single pulmonary artery, innervated by the left vagus. Activity in this nerve controls pulmonary conductance so that left vagotomy abolishes this control. Experimental left vagotomy to abolish cardiac shunting had no effect on long-term survival and failed to identify a functional role in determining metabolic rate, growth or resistance to food deprivation. Accordingly, the present investigation sought to evaluate the extent to which cardiac shunt patterns are actively controlled during changes in body temperature and activity levels. We compared hemodynamic parameters between intact and left-vagotomized rattlesnakes held at different temperatures and subjected to enforced physical activity. Increased temperature and enforced activity raised heart rate, cardiac output, pulmonary and systemic blood flow in both groups, but net cardiac shunt was reversed in the vagotomized group at lower temperatures. We conclude that vagal control of pulmonary conductance is an active mechanism regulating cardiac shunts in C. durissus.
Feng, Pu; Huang, Liquan; Wang, Hong
The mammalian taste bud is an onion-shaped epithelial structure with 50–100 tightly packed cells, including taste receptor cells, supporting cells, and basal cells. Taste receptor cells detect nutrients and toxins in the oral cavity and transmit the sensory information to gustatory nerve endings in the buds. Supporting cells may play a role in the clearance of excess neurotransmitters after their release from taste receptor cells. Basal cells are precursor cells that differentiate into mature...
Smutzer, Gregory; Patel, Janki Y.; Stull, Judith C.; Abarintos, Ray A.; Khan, Neiladri K.; Park, Kevin C.
A novel delivery method is described for the rapid determination of taste preferences for sweet taste in humans. This forced-choice paired comparison approach incorporates the non-caloric sweetener sucralose into a set of one-inch square edible strips for the rapid determination of sweet taste preferences. When compared to aqueous sucrose solutions, significantly lower amounts of sucralose were required to identify the preference for sweet taste. The validity of this approach was determined by comparing sweet taste preferences obtained with five different sucralose-containing edible strips to a set of five intensity-matched sucrose solutions. When compared to the solution test, edible strips required approximately the same number of steps to identify the preferred amount of sweet taste stimulus. Both approaches yielded similar distribution patterns for the preferred amount of sweet taste stimulus. In addition, taste intensity values for the preferred amount of sucralose in strips were similar to that of sucrose in solution. The hedonic values for the preferred amount of sucralose were lower than for sucrose, but the taste quality of the preferred sucralose strip was described as sweet. When taste intensity values between sucralose strips and sucralose solutions containing identical amounts of taste stimulus were compared, sucralose strips produced a greater taste intensity and more positive hedonic response. A preference test that uses edible strips for stimulus delivery should be useful for identifying preferences for sweet taste in young children, and in clinical populations. This test should also be useful for identifying sweet taste preferences outside of the lab or clinic. Finally, edible strips should be useful for developing preference tests for other primary taste stimuli and for taste mixtures. PMID:24225255
Smutzer, Gregory; Patel, Janki Y; Stull, Judith C; Abarintos, Ray A; Khan, Neiladri K; Park, Kevin C
A novel delivery method is described for the rapid determination of taste preferences for sweet taste in humans. This forced-choice paired comparison approach incorporates the non-caloric sweetener sucralose into a set of one-inch square edible strips for the rapid determination of sweet taste preferences. When compared to aqueous sucrose solutions, significantly lower amounts of sucralose were required to identify the preference for sweet taste. The validity of this approach was determined by comparing sweet taste preferences obtained with five different sucralose-containing edible strips to a set of five intensity-matched sucrose solutions. When compared to the solution test, edible strips required approximately the same number of steps to identify the preferred amount of sweet taste stimulus. Both approaches yielded similar distribution patterns for the preferred amount of sweet taste stimulus. In addition, taste intensity values for the preferred amount of sucralose in strips were similar to that of sucrose in solution. The hedonic values for the preferred amount of sucralose were lower than for sucrose, but the taste quality of the preferred sucralose strip was described as sweet. When taste intensity values between sucralose strips and sucralose solutions containing identical amounts of taste stimulus were compared, sucralose strips produced a greater taste intensity and more positive hedonic response. A preference test that uses edible strips for stimulus delivery should be useful for identifying preferences for sweet taste in young children, and in clinical populations. This test should also be useful for identifying sweet taste preferences outside of the lab or clinic. Finally, edible strips should be useful for developing preference tests for other primary taste stimuli and for taste mixtures. Copyright © 2013 Elsevier Ltd. All rights reserved.
Smutzer, Gregory; Patel, Janki Y.; Stull, Judith C.; Abarintos, Ray A.; Khan, Neiladri K.; Park, Kevin C.
A novel delivery method is described for the rapid determination of taste preferences for sweet taste in humans. This forced-choice paired comparison approach incorporates the non-caloric sweetener sucralose into a set of one-inch square edible strips for the rapid determination of sweet taste preferences. When compared to aqueous sucrose solutions, significantly lower amounts of sucralose were required to identify the preference for sweet taste. The validity of this approach was determined b...
Asao, Keiko; Luo, Wendy; Herman, William H.
Developing interventions to prevent and treat obesity are medical and public health imperatives. Taste is a major determinant of food intake and reliable methods to measure taste preferences need to be established. This study aimed to establish the short-term reproducibility of sweet taste preference measurements using 5-level sucrose concentrations in healthy adult volunteers. We defined sweet taste preference as the geometric mean of the preferred sucrose concentration determined from two s...
Spetter, M.S.; Smeets, P.A.M.; Graaf, de C.; Viergever, M.A.
The intensity of the taste of a food is affected mostly by the amount of sugars (mono- and disaccharides) or salt it contains. To season savory-tasting foods mainly table salt (NaCl) is used and to sweeten foods, sugars like sucrose are used. Foods with highly intense tastes are consumed in smaller
Theunissen, M.J.M.; Polet, I.A.; Kroeze, J.H.A.; Schifferstein, H.N.J.
Taste adaptation, a gradual decline of taste intensity with prolonged stimulation, is frequently observed in laboratory experiments. However, during normal eating the taste of food does not seem to decrease or disappear. During eating, the presence of saliva, the interactions between tastants and
An examination of the oral mucosa of Crotalus and several Scolecophidia revealed the presence of taste buds. The taste buds in these two divergent groups of snakes are similar in appearance, and correspond to previous descriptions of gustatory organs in other reptiles. Few taste buds were present in any specimen, and ...
Normotensos com resposta pressórica exagerada ao exercício possuem tônus vagal cardíaco aumentado Normotensos con respuesta presora exagerada al ejercicio poseen tono vagal cardíaco aumentado Normotensive individuals with exaggerated exercise blood pressure response have increased cardiac vagal tone
Plínio Santos Ramos
individuos sanos con una respuesta presora exagerada en el TCPE. OBJETIVO: Analizar el comportamiento del TVC en hombres adultos sanos que presentan una respuesta presora exagerada en el TCPE. MÉTODOS: De 2.505 casos evaluados entre 2002-2009, fueron identificados criteriosamente 154 casos de hombres, entre 20-50 años de edad, sanos y normotensos. La evaluación incluía examen clínico, medidas antropométricas, pruebas de ejercicio de 4 segundos (tono vagal cardíaco y TCPE realizado en cicloergómetro, con medidas de presión arterial a cada minuto por el método auscultatorio. Basado en el valor máximo de PAS obtenido en el TCPE, la muestra fue dividida en terciles, comparándose el TVC, la carga máxima y el VO2 máximo. RESULTADOS: Los valores de TVC difirieron entre los individuos que se presentaban en los terciles inferior y superior para la respuesta de la PAS al TCPE, respectivamente, 1,57 ± 0,03 y 1,65 ± 0,04 (promedio ± error estándar del promedio (p = 0,014. Los dos terciles también diferían en cuanto al VO2 máximo (40,7 ± 1,3 vs 46,4 ± 1,3 ml/kg-1.min-1; p = 0,013 y la carga máxima (206 ± 6,3 vs 275 ± 8,7 watts; p BACKGROUND: Exaggerated systolic blood pressure (SBP levels during a maximal cardiopulmonary exercise test (CPET are classically considered as inappropriate and associated with a higher risk for the development of cardiovascular diseases. It is known that the autonomic nervous system modulates the BP during exercise. However, the behavior of the cardiac vagal tone (CVT has not been fully established in healthy individuals with an exaggerated BP response to CPET. OBJECTIVE: To analyze the behavior of the CVT in healthy adult males presenting an exaggerated BP response to CPET. METHODS: Of the 2,505 cases evaluated between 2002-2009, 154 cases were thoroughly identified, consisting of healthy male normotensive subjects aged 20-50 years. The evaluation included clinical assessment, anthropometric measurements, 4-second exercise test
Ronveaux, Charlotte C; Tomé, Daniel; Raybould, Helen E
Emerging evidence has suggested a possible physiologic role for peripheral glucagon-like peptide 1 (GLP-1) in regulating glucose metabolism and food intake. The likely site of action of GLP-1 is on vagal afferent neurons (VANs). The vagal afferent pathway is the major neural pathway by which information about ingested nutrients reaches the central nervous system and influences feeding behavior. Peripheral GLP-1 acts on VANs to inhibit food intake. The mechanism of the GLP-1 receptor (GLP-1R) is unlike other gut-derived receptors; GLP-1Rs change their cellular localization according to feeding status rather than their protein concentrations. It is possible that several gut peptides are involved in mediating GLP-1R translocation. The mechanism of peripheral GLP-1R translocation still needs to be elucidated. We review data supporting the role of peripheral GLP-1 acting on VANs in influencing glucose homeostasis and feeding behavior. We highlight evidence demonstrating that GLP-1 interacts with ghrelin and leptin to induce satiation. Our aim was to understand the mechanism of peripheral GLP-1 in the development of noninvasive antiobesity treatments. © 2015 American Society for Nutrition.
Subramanian, Hari H; Huang, Zheng-Gui; Silburn, Peter A; Balnave, Ron J; Holstege, Gert
The nucleus retroambiguus (NRA) is a neuronal cell group in the medullary ventrolateral tegmentum, rostrocaudally between the obex and the first cervical spinal segment. NRA neurons are premotor interneurons with direct projections to the motoneurons of soft palate, pharynx, and larynx in the nucleus ambiguus in the lateral medulla as well as to the motoneurons in the spinal cord innervating diaphragm, abdominal, and pelvic floor muscles and the lumbosacral motoneurons generating sexual posture. These NRA premotor interneurons receive very strong projections from the periaqueductal gray (PAG) in the context of basic survival mechanisms as fight, flight, freezing, sound production, and sexual behavior. In the present study in rat we investigated the physiological motor patterns generated by NRA neurons, as the result of vagal, peripheral chemosensory, and nociceptive stimulation. The results show that the NRA contains phasic respiratory modulated neurons, as well as nonphasic tonically modulated neurons. Stimulation in the various rostrocaudal levels of the NRA generates site-specific laryngeal, respiratory, abdominal, and pelvic floor motor activities. Vagal and peripheral chemosensory stimulation induces both excitatory and inhibitory modulation of phasic NRA-neurons, while peripheral chemosensory and nociceptive stimulation causes excitation and inhibition of nonphasic NRA-neurons. These results are in agreement with the concept that the NRA represents a multifunctional group of neurons involved in the output of the emotional motor system, such as vomiting, vocalization, mating, and changes in respiration. © 2017 Wiley Periodicals, Inc.
Armstrong, Jessica E; Laing, David G; Jinks, Anthony L
The state of development of the sense of taste in humans during the first few months of life is only partially understood. Since taste plays a critical role in the feeding and nutrition of infants a better understanding of taste development during early life is required. Currently, information about the sense of taste in pre-verbal infants is obtained by analysis of videotaped facial expressions using the Baby FACS coding system. A potentially more objective faster procedure for assessing facial expressions not investigated in infants is electromyography (EMG). The method has been successfully used to study taste-elicited responses in the mid-face muscle regions of the levator labii and zygomaticus major of 6-9-year-olds and in a range of facial muscle regions in adults. Accordingly, this study aimed to investigate taste in young infants using EMG to 1) measure activity simultaneously in 4 facial muscle regions in response to 3 common tastants and 2) determine whether the activities of one or more muscle regions is needed to provide evidence of perception of a tastant by an infant. The results indicated that multiple facial muscle regions responded simultaneously but differentially to non-sweet and sweet tastants and recordings of activities from 3 or 4 regions simultaneously indicated that almost 100% of infants responded to the unpleasant tastes of quinine and citric acid, and 80% to sucrose. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: email@example.com.
Diaz-Cenzano, Elena; Chotro, M Gabriela
With infant rats, unlike with adults, increased intake of a taste after mere exposure to this stimulus is not consistently found; this has sometimes been interpreted as a failure by the immature subject to recognize tastes as familiar. We studied the effect of preexposure to a tastant, measuring taste reactivity and intake in 14-day-old rats. Familiarity increased hedonic response to sucrose, but also increased aversive response to quinine and ethanol. With the sucrose-quinine compound, familiarity increased both the hedonic and the aversive reaction to the stimulus. In no case was a differential reactivity to water observed. Significant increased intake after familiarization was only found with quinine or the sucrose-quinine compound. Results indicate that in infant rats, and with the present parameters, taste familiarity enhances responsiveness to these stimuli, an effect not always accompanied by detectable changes in intake.
Full Text Available Using survey and experimental data, the present research examines the effect of brand perception on experienced taste. The content of brand perception can be organized along the two social perception dimensions of warmth and competence. We use these two dimensions to systematically investigate the influence of brand perception on experienced taste and consumer behavior toward food products. The brand’s perceived warmth and competence independently influenced taste, both when it was measured as a belief and as an embodied experience following consumption. Taste mediated the link between brand’s warmth and competence perceptions and three consumer behavioral tendencies crucial for the marketing success of brands: buying intentions, brand loyalty, and support for the brand.
Lopez, R; Mateo-Vivaracho, L; Cacho, J; Ferreira, V
A procedure for the general taste dilution analysis (TDA) of wine has been optimized and applied to characterize the tastants of 5 different wines. Samples are concentrated first by vacuum distillation at 20 degrees C to obtain a dearomatized concentrate. Such concentrate is redissolved in water and injected in a semipreparative C18-high performance liquid chromatography (HPLC) column. The effluent is separated in fractions that are collected and concentrated by vacuum distillation. Sequential dilutions of the fractions are further evaluated by a sensory panel to assess the intensity of the basic tastes and in-mouth sensations. Fractions were also submitted to HPLC-mass spectrometry (MS) analysis to screen for known tastants of wines. The Taste Dilution chromatograms showed that taste differences between wines are mainly located in fractions 1, 2, and 6, and are mainly related to bitterness and astringency. Different aspects of the method setup and of its reliability are evaluated and discussed.
Ginane, Cécile; Baumont, René; Favreau-Peigné, Angélique
Taste is one of the five senses that give ruminants and other animals an awareness of their environment, especially for food selection. The sense of taste, which recognizes sweet, bitter, salty, sour and umami basic tastes, is often considered of paramount importance as it is the last sense in use before foods are swallowed. It thus plays a fundamental biological role in aiding animals to regulate intake of suitable food and reject unsuitable food. However, despite potentially relevant production and welfare issues, only a few studies have investigated how ruminants perceive and evaluate the basic tastes. Here we review current knowledge on tasting abilities and hedonic value of basic tastes in domestic ruminants via the analysis of both their anatomical and neurological structures and their behavioral preferences. Studies of the organization and functioning of the anatomical and neurological structures responsible for the perception of taste in ruminants have shown that sheep, cattle and goats all have lingual receptors for all five basic tastes. However, these studies have mainly focused on the sweet and bitter tastes. They have shown in particular that cows have fewer genes coding for the bitter receptors than other mammals, making them more tolerant to this taste. This pattern has been linked to the differences in the range of toxins and so potentially in the occurrence of bitterness encountered by different species in their environment, depending on the nature of their diet. Studies of ruminant feeding behavior have shown that the taste inducing the greatest consensus in preferences is the umami taste, with a high positive hedonic value. The bitter taste seems to have a rather negative hedonic value, the salty taste either a positive or a negative one depending on body needs, while the sweet taste seems to have a positive value in cattle and goats but not in sheep. Finally, the hedonic value of the sour taste is uncertain. Besides the hedonic value, the animal
This thesis contains studies on intensity and pleasantness in taste perception. There is a formal relationship between intensity and hedonic value of stimuli, which can be expressed in an inverted U. The fact that pleasantness depends partially on stimulus intensity poses a problem when one wants to
Home; Journals; Resonance – Journal of Science Education; Volume 12; Issue 9. A Taste of Functional Programming – 2. Madhavan Mukund. General Article Volume 12 Issue 9 September 2007 pp 40-63. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/012/09/0040-0063 ...
Mozgot, V. G.
Data from a longitudinal survey of the musical tastes of young people distinguish five basic vectors of its development: an orientation toward the Western paradigm; young people's unlimited amount of time spent in the consumption of music; the indiscriminate nature of their music interests; the influence that a person's membership in a particular…
van Eijck, K.
In this article, we investigate patterns of musical taste using a large sample from the Dutch population. It is found that members from higher-status groups tend to be more omnivorous (that is, they like more different musical genres) than those from lower-status groups, which is in line with
Gilboa, Itzhak; Samet, Dov; Schmeidler, David
Harsanyi's utilitarianism is extended here to Savage's framework. We formulate a Pareto condition that implies that both society's utility function and its probability measure are linear combinations of those of the individuals. An indiscriminate Pareto condition has been shown to contradict linear aggregation of beliefs and tastes. We argue that…
Dean, Michael L.
Presentation order in paired-comparison testing was varied to measure the impact of primacy v recency effects on consumer product evaluation. First position preference bias characterized the findings, lending support to the attention decrement hypothesis or a suggested palate desensitization effect on subsequent taste trial behavior. (Author)
Karel, M.; Nakhost, Z.
Report describes investigation of chemical composition of blue-green algae Synechococcus 6311, as well as preparation of protein isolate from green alga Scenedesmus obliquus and incorporation into variety of food products evaluated for taste. Part of program to investigate growth of microalgae aboard spacecraft for use as food.
Levy, C J; Carroll, M E; Smith, J C; Hofer, K G
When rats are treated with an antihistamine prior to being given sublethal doses of ionizing radiation, the formation of a conditioned saccharin aversion is completely inhibited. A profound aversion could be conditioned with histamine diphosphate as the aversive stimulus. The increase in histamine production after radiation exposure represents the physiological basis of radiation-induced taste aversions.
Gagnon, Lea; Kupers, Ron; Ptito, Maurice
further indicate that blind subjects more strongly rely on internal hunger and satiety cues, instead of external contextual or emotional cues, to decide when and what to eat. We suggest that the lower taste sensitivity observed in congenitally blind individuals is due to various blindness...
Houben, Manon; van Nes, A.|info:eu-repo/dai/nl/176956174; Tobias, T.J.|info:eu-repo/dai/nl/323926789
Background The aim of this trial was to test whether the temperature or additives of the drinking water affected water uptake by nursery pigs. We designed a repeated 4 × 4 Latin Square to control for confounding factors such as; carry-over effects, learning of a preferential taste, daily variation
Neyraud, E.; Peyron, M.A.; Vieira, C.; Dransfield, E.
Mastication is a rhythmic activity that can be modified by peripheral information generated in the mouth. To study whether taste cognition could influence the way in which a food is broken down in the mouth, subjects masticated firm, sugar-based gelatine gels with differing concentrations of
Full Text Available Jacob Juel,1 Christina Brock,1–4 Søren S Olesen,1,2 Adnan Madzak,5 Adam D Farmer,5–7 Qasim Aziz,7 Jens B Frøkjær,2,5 Asbjørn Mohr Drewes1,2 1Mech-Sense, Department of Gastroenterology and Hepatology, Aalborg University Hospital, 2Department of Clinical Medicine, Aalborg University, Aalborg, 3Department of Rheumatology, Aarhus University Hospital, Aarhus, 4Drug Design and Pharmacology, University of Copenhagen, Copenhagen, 5Mech-Sense, Department of Radiology, Aalborg University Hospital, Aalborg, Denmark; 6Department of Gastroenterology, University Hospitals of North Midlands, Stoke-on-Trent, 7Centre for Neuroscience and Trauma, Blizard Institute, Wingate Institute of Neurogastroenterology, Barts and the London School of Medicine & Dentistry, Queen Mary University of London, London, UK Background: The effective management of pain in chronic pancreatitis (CP remains a therapeutic challenge. Analgesic drugs, such as opioids, and the underlying pathology can impair gut function. The autonomic nervous system influences hormone secretion and gut motility. In healthy volunteers, electrical (using noninvasive transcutaneous vagal nerve stimulation [t-VNS] and physiological (using deep slow breathing [DSB] modulation of parasympathetic tone results in pain attenuation and enhanced gut motility. Thus, the aims were to investigate whether t-VNS and DSB could enhance the parasympathetic tone, decrease pain sensitivity and improve gut motility in CP.Patients and methods: A total of 20 patients (12 males, mean age=61 years, range: 50–78 years with CP were randomized to short-term (60 minutes t-VNS and DSB, or their placebo equivalent, in a crossover design. Cardiometrically derived parameters of autonomic tone, quantitative sensory testing of bone and muscle pain pressure, conditioned pain modulation (CPM and assessments of gastroduodenal motility with ultrasound were performed.Results: In comparison to sham, t-VNS and DSB increased cardiac
Skyberg, Rolf; Sun, Chengsan; Hill, David L
Neural activity plays a critical role in the development of central circuits in sensory systems. However, the maintenance of these circuits at adulthood is usually not dependent on sensory-elicited neural activity. Recent work in the mouse gustatory system showed that selectively deleting the primary transduction channel for sodium taste, the epithelial sodium channel (ENaC), throughout development dramatically impacted the organization of the central terminal fields of three nerves that carry taste information to the nucleus of the solitary tract. More specifically, deleting ENaCs during development prevented the normal maturation of the fields. The present study was designed to extend these findings by testing the hypothesis that the loss of sodium taste activity impacts the maintenance of the normal adult terminal field organization in male and female mice. To do this, we used an inducible Cre-dependent genetic recombination strategy to delete ENaC function after terminal field maturation occurred. We found that removal of sodium taste neural activity at adulthood resulted in significant reorganization of mature gustatory afferent terminal fields in the nucleus of the solitary tract. Specifically, the chorda tympani and greater superficial petrosal nerve terminal fields were 1.4× and 1.6× larger than age-matched controls, respectively. By contrast, the glossopharyngeal nerve, which is not highly sensitive to sodium taste stimulation, did not undergo terminal field reorganization. These surprising results suggest that gustatory nerve terminal fields remain plastic well into adulthood, which likely impacts central coding of taste information and taste-related behaviors with altered taste experience. SIGNIFICANCE STATEMENT Neural activity plays a major role in the development of sensory circuits in the mammalian brain. However, the importance of sensory-driven activity in maintaining these circuits at adulthood, especially in subcortical structures, appears to be
Singh, Preet Bano
Monosodium glutamate elicits a specific umami taste and increases palatability of food. In order to comprehensively study the mechanisms of the taste perception of glutamate, this work compiles results from several research fields namely, psychophysics, molecular biology and neurophysiology. At the perception level, the aim of the study was to explore individual variation in the perception of glutamate in the healthy population. At the cellular level, the question referred to the role of s...
Gaillard, Dany; Xu, Mingang; Millar, Sarah E.
Taste stimuli are transduced by taste buds and transmitted to the brain via afferent gustatory fibers. Renewal of taste receptor cells from actively dividing progenitors is finely tuned to maintain taste sensitivity throughout life. We show that conditional β-catenin deletion in mouse taste progenitors leads to rapid depletion of progenitors and Shh+ precursors, which in turn causes taste bud loss, followed by loss of gustatory nerve fibers. In addition, our data suggest LEF1, TCF7 and Wnt3 are involved in a Wnt pathway regulatory feedback loop that controls taste cell renewal in the circumvallate papilla epithelium. Unexpectedly, taste bud decline is greater in the anterior tongue and palate than in the posterior tongue. Mutant mice with this regional pattern of taste bud loss were unable to discern sweet at any concentration, but could distinguish bitter stimuli, albeit with reduced sensitivity. Our findings are consistent with published reports wherein anterior taste buds have higher sweet sensitivity while posterior taste buds are better tuned to bitter, and suggest β-catenin plays a greater role in renewal of anterior versus posterior taste buds. PMID:28846687
Cygankiewicz, Adam I; Maslowska, Alicja; Krajewska, Wanda M
Taste perception is one of the senses crucial for many organisms. There are five basic tastes, i.e., sweet, bitter, salty, sour, and umami, and it is suggested that the taste of fat should be included in this list. This paper reviews the current state of knowledge about the involvement of G protein coupled receptors (GPCRs) in taste sensing and intracellular signaling. GPCR receptors are focal point of interest for pharmaceutical industry. However, their ability to interact with a variety of taste substances makes these receptors interesting target for food and nutrient companies.
Full Text Available Taste and smell alterations have been recognized as common symptoms in relation to various cancers. However, previous research suggests that patients do not receive sufficient support in managing taste and smell alterations. Therefore, the objective of this study is to investigate how persons with experience from lung cancer-related taste and smell alterations reason about resources and strategies offered and used to manage these symptoms. Data from semi-structured individual interviews with 13 women and four men were analyzed with qualitative content analysis. We used Kleinman's now classic medical anthropological model of local health care systems, consisting of the personal, professional, and folk sector, to interpret and understand how people respond to sickness experiences in their daily lives. By presenting the findings using this model, we demonstrate that most strategies for dealing with taste and smell alterations were undertaken in the personal sector, i.e. in participants' daily lives, on an individual level and in interaction with family, social networks and communities. Taste and smell alterations implied two overarching challenges: 1 adjusting to no longer being able to trust information provided by one's own senses of taste and/or smell, and 2 coming to terms with taste and smell alterations as a part of having lung cancer. Health care professionals' involvement was described as limited, but appeared to fulfil most participants' expectations. However, through provision of normalizing information, practical advice, and to some extent, emotional support, health care professionals had potential to influence strategies and resources used for dealing with taste and smell alterations. With this study, we further the understanding of how people deal with lung cancer-related taste and smell alterations and discuss the role of health care professionals for this process.
King, Camille T; Garcea, Mircea; Stolzenberg, Danielle S; Spector, Alan C
Studies examining the effects of transection and regeneration of the glossopharyngeal (GL) and chorda tympani (CT) nerves on various taste-elicited behaviors in rats have demonstrated that the GL (but not the CT) nerve is essential for the maintenance of both an unconditioned protective reflex (gaping) and the neural activity observed in central gustatory structures in response to lingual application of a bitter substance. An unresolved issue, however, is whether recovery depends more on the taste nerve and the central circuits that it supplies and/or on the tongue receptor cell field being innervated. To address this question, we experimentally cross-wired these taste nerves, which, remarkably, can regenerate into parts of the tongue they normally do not innervate. We report that quinine-stimulated gaping behavior was fully restored, and neuronal activity, as assessed by Fos immunohistochemistry in the nucleus of the solitary tract and the parabrachial nucleus, was partially restored only if the posterior tongue (PT) taste receptor cell field was reinnervated; the particular taste nerve supplying the input was inconsequential to the recovery of function. Thus, PT taste receptor cells appear to play a privileged role in triggering unconditioned gaping to bitter tasting stimuli, regardless of which lingual gustatory nerve innervates them. Our findings demonstrate that even when a lingual gustatory nerve (the CT) forms connections with taste cells in a non-native receptor field (the PT), unconditioned taste rejection reflexes to quinine can be maintained. These findings underscore the extraordinary ability of the gustatory system to adapt to peripherally reorganized input for particular behaviors.
Munger Steven D
Full Text Available Abstract Background The detection of bitter-tasting compounds by the gustatory system is thought to alert animals to the presence of potentially toxic food. Some, if not all, bitter stimuli activate specific taste receptors, the T2Rs, which are expressed in subsets of taste receptor cells on the tongue and palate. However, there is evidence for both receptor-dependent and -independent transduction mechanisms for a number of bitter stimuli, including quinine hydrochloride (QHCl and denatonium benzoate (DB. Results We used brief-access behavioral taste testing of BXD/Ty recombinant inbred (RI mouse strains to map the major quantitative trait locus (QTL for taste sensitivity to QHCl. This QTL is restricted to a ~5 Mb interval on chromosome 6 that includes 24 genes encoding T2Rs (Tas2rs. Tas2rs at this locus display in total 307 coding region single nucleotide polymorphisms (SNPs between the two BXD/Ty RI parental strains, C57BL/6J (quinine-sensitive and DBA/2J (quinine insensitive; approximately 50% of these mutations are silent. Individual RI lines contain exclusively either C57BL/6J or DBA/2J Tas2r alleles at this locus, and RI lines containing C57BL/6J Tas2r alleles are more sensitive to QHCl than are lines containing DBA/2J alleles. Thus, the entire Tas2r cluster comprises a large haplotype that correlates with quinine taster status. Conclusion These studies, the first using a taste-salient assay to map the major QTL for quinine taste, indicate that a T2R-dependent transduction cascade is responsible for the majority of strain variance in quinine taste sensitivity. Furthermore, the large number of polymorphisms within coding exons of the Tas2r cluster, coupled with evidence that inbred strains exhibit largely similar bitter taste phenotypes, suggest that T2R receptors are quite tolerant to variation.
Sun, Chengsan; Hummler, Edith
Neuronal activity plays a key role in the development of sensory circuits in the mammalian brain. In the gustatory system, experimental manipulations now exist, through genetic manipulations of specific taste transduction processes, to examine how specific taste qualities (i.e., basic tastes) impact the functional and structural development of gustatory circuits. Here, we used a mouse knock-out model in which the transduction component used to discriminate sodium salts from other taste stimuli was deleted in taste bud cells throughout development. We used this model to test the hypothesis that the lack of activity elicited by sodium salt taste impacts the terminal field organization of nerves that carry taste information from taste buds to the nucleus of the solitary tract (NST) in the medulla. The glossopharyngeal, chorda tympani, and greater superficial petrosal nerves were labeled to examine their terminal fields in adult control mice and in adult mice in which the α-subunit of the epithelial sodium channel was conditionally deleted in taste buds (αENaC knockout). The terminal fields of all three nerves in the NST were up to 2.7 times greater in αENaC knock-out mice compared with the respective field volumes in control mice. The shapes of the fields were similar between the two groups; however, the density and spread of labels were greater in αENaC knock-out mice. Overall, our results show that disruption of the afferent taste signal to sodium salts disrupts the normal age-dependent “pruning” of all terminal fields, which could lead to alterations in sensory coding and taste-related behaviors. SIGNIFICANCE STATEMENT Neural activity plays a major role in the development of sensory circuits in the mammalian brain. To date, there has been no direct test of whether taste-elicited neural activity has a role in shaping central gustatory circuits. However, recently developed genetic tools now allow an assessment of how specific taste stimuli, in this case
Sun, Chengsan; Hummler, Edith; Hill, David L
Neuronal activity plays a key role in the development of sensory circuits in the mammalian brain. In the gustatory system, experimental manipulations now exist, through genetic manipulations of specific taste transduction processes, to examine how specific taste qualities (i.e., basic tastes) impact the functional and structural development of gustatory circuits. Here, we used a mouse knock-out model in which the transduction component used to discriminate sodium salts from other taste stimuli was deleted in taste bud cells throughout development. We used this model to test the hypothesis that the lack of activity elicited by sodium salt taste impacts the terminal field organization of nerves that carry taste information from taste buds to the nucleus of the solitary tract (NST) in the medulla. The glossopharyngeal, chorda tympani, and greater superficial petrosal nerves were labeled to examine their terminal fields in adult control mice and in adult mice in which the α-subunit of the epithelial sodium channel was conditionally deleted in taste buds (αENaC knockout). The terminal fields of all three nerves in the NST were up to 2.7 times greater in αENaC knock-out mice compared with the respective field volumes in control mice. The shapes of the fields were similar between the two groups; however, the density and spread of labels were greater in αENaC knock-out mice. Overall, our results show that disruption of the afferent taste signal to sodium salts disrupts the normal age-dependent "pruning" of all terminal fields, which could lead to alterations in sensory coding and taste-related behaviors. Neural activity plays a major role in the development of sensory circuits in the mammalian brain. To date, there has been no direct test of whether taste-elicited neural activity has a role in shaping central gustatory circuits. However, recently developed genetic tools now allow an assessment of how specific taste stimuli, in this case sodium salt taste, play a role
Full Text Available The aim of this study was to research the morphological changes of neurons in the vagus nerve nuclei in medulla oblongata in asphyxia related death cases. Morphological changes that were investigated were mainly in the dorsal motor respiratory center (DMRC, nucleus tractus solitarius (nTS and nucleus ambigus (nA in the medulla oblongata. In our research, the autopsy material from asphyxia related death cases was used from various etiologies: monoxide carbon (CO, liquid drowning, strangulation, electricity, clinical-pathological death, firing weapon, explosive weapon, sharp and blunt objects and death cases due to accident. The material selected for research was taken from medulla oblongata and lungs from all lobes. The material from the medulla oblongata and lungs was fixed in a 10% solution of buffered formalin. Special histochemical methods for central nervous system (CNS were employed like: Cresyl echt violet, toluidin blue, Sevier-Munger modification and Grimelius. For stereometrical analysis of the quantitative density of the neurons the universal testing system Weibel M42 was used. The acquired results show that in sudden asphyxia related death cases, there are alterations in the nuclei of vagal nerve in form of: central chromatolysis, axonal retraction, axonal fragmentation, intranuclear vacuolization, cytoplasmic vacuolization, edema, condensation and dispersion of substance of Nissl, proliferation of oligodendrocytes, astrocytes and microglia. The altered population of vagus nerve neurons does not show an important statistica! significarne compared to the overall quantity of the neurons in the nuclei of the vagus nerve (p<0,05.
Full Text Available We have developed a new portable taste sensor with a lipid/polymer membrane and conducted experiments to evaluate the sensor’s performance. The fabricated sensor consists of a taste sensor chip (40 mm × 26 mm × 2.2 mm with working and reference electrodes and a portable sensor device (80 mm × 25 mm × 20 mm. The working electrode consists of a taste-sensing site comprising a poly(hydroxyethylmethacrylate (pHEMA hydrogel layer with KCl as the electrolyte layer and a lipid/polymer membrane as the taste sensing element. The reference electrode comprises a polyvinyl chloride (PVC membrane layer with a small hole and a pHEMA layer with KCl. The whole device is the size of a USB memory stick, making it suitable for portable use. The sensor’s response to tannic acid as the standard astringency substance showed good accuracy and reproducibility, and was comparable with the performance of a commercially available taste sensing system. Thus, it is possible for this sensor to be used for in-field evaluations and it can make a significant contribution to the food industry, as well as in various fields of research.
Rolls, Edmund T
The anterior insula contains the primary taste cortex, in which neurons in primates respond to different combinations providing a distributed representation of different prototypical tastes, oral texture including fat texture, and oral temperature. These taste neurons do not represent food reward value, in that feeding to satiety does not reduce their responses to zero, in contrast to the next stage of processing, the orbitofrontal cortex, where food reward value is represented. Corresponding results are found with fMRI in humans. A more ventral part of the anterior insula is implicated using fMRI in autonomic-visceral functions. 'Salient' stimuli, including rewarding, punishing, non-rewarding, and novel stimuli may activate this viscero-autonomic system, via inputs received from regions that represent these stimuli such as the orbitofrontal and anterior cingulate cortex. More posteriorly in the insula, there is an oral somatosensory region, and posterior to this somatosensory regions that respond to touch to the body. These taste and somatosensory representations in the insula provide representations that are about the external world (touch), are intermediate (oral taste and texture), and are about internal signals related to visceral and autonomic function. This functionality needs to be taken into account when considering activations of the insula found in cognitive tasks. Copyright © 2015 Elsevier Inc. All rights reserved.
Full Text Available The polycystic kidney disease-like ion channel PKD2L1 and its associated partner PKD1L3 are potential candidates for sour taste receptors. PKD2L1 is expressed in type III taste cells that respond to sour stimuli and genetic elimination of cells expressing PKD2L1 substantially reduces chorda tympani nerve responses to sour taste stimuli. However, the contribution of PKD2L1 and PKD1L3 to sour taste responses remains unclear.We made mice lacking PKD2L1 and/or PKD1L3 gene and investigated whole nerve responses to taste stimuli in the chorda tympani or the glossopharyngeal nerve and taste responses in type III taste cells. In mice lacking PKD2L1 gene, chorda tympani nerve responses to sour, but not sweet, salty, bitter, and umami tastants were reduced by 25-45% compared with those in wild type mice. In contrast, chorda tympani nerve responses in PKD1L3 knock-out mice and glossopharyngeal nerve responses in single- and double-knock-out mice were similar to those in wild type mice. Sour taste responses of type III fungiform taste cells (GAD67-expressing taste cells were also reduced by 25-45% by elimination of PKD2L1.These findings suggest that PKD2L1 partly contributes to sour taste responses in mice and that receptors other than PKDs would be involved in sour detection.
Full Text Available Taste is a property that is thought to potentially modulate swallowing behavior. Whether such effects depend on taste, intensity remains unclear. This study explored differences in the amplitudes of tongue-palate pressures in swallowing as a function of taste stimulus concentration. Tongue-palate pressures were collected in 80 healthy women, in two age groups (under 40, over 60, stratified by genetic taste status (nontasters, supertasters. Liquids with different taste qualities (sweet, sour, salty, and bitter were presented in high and low concentrations. General labeled magnitude scale ratings captured perceived taste intensity and liking/disliking of the test liquids. Path analysis explored whether factors of taste, concentration, age group, and/or genetic taste status impacted: (1 perceived intensity; (2 palatability; and (3 swallowing pressures. Higher ratings of perceived intensity were found in supertasters and with higher concentrations, which were more liked/disliked than lower concentrations. Sweet stimuli were more palatable than sour, salty, or bitter stimuli. Higher concentrations elicited stronger tongue-palate pressures independently and in association with intensity ratings. The perceived intensity of a taste stimulus varies as a function of stimulus concentration, taste quality, participant age, and genetic taste status and influences swallowing pressure amplitudes. High-concentration salty and sour stimuli elicit the greatest tongue-palate pressures.
Full Text Available Crohn's disease (CD and irritable bowel syndrome (IBS involve brain-gut dysfunctions where vagus nerve is an important component. The aim of this work was to study the association between vagal tone and markers of stress and inflammation in patients with CD or IBS compared to healthy subjects (controls. The study was performed in 73 subjects (26 controls, 21 CD in remission and 26 IBS patients. The day prior to the experiment, salivary cortisol was measured at 8:00 AM and 10:00 PM. The day of the experiment, subjects completed questionnaires for anxiety (STAI and depressive symptoms (CES-D. After 30 min of rest, ECG was recorded for heart rate variability (HRV analysis. Plasma cortisol, epinephrine, norepinephrine, TNF-alpha and IL-6 were measured in blood samples taken at the end of ECG recording. Compared with controls, CD and IBS patients had higher scores of state-anxiety and depressive symptomatology. A subgroup classification based on HRV-normalized high frequency band (HFnu as a marker of vagal tone, showed that control subjects with high vagal tone had significantly lower evening salivary cortisol levels than subjects with low vagal tone. Such an effect was not observed in CD and IBS patients. Moreover, an inverse association (r = -0.48; p<0.05 was observed between the vagal tone and TNF-alpha level in CD patients exclusively. In contrast, in IBS patients, vagal tone was inversely correlated with plasma epinephrine (r = -0.39; p<0.05. No relationship was observed between vagal tone and IL-6, norepinephrine or negative affects (anxiety and depressive symptomatology in any group. In conclusion, these data argue for an imbalance between the hypothalamus-pituitary-adrenal axis and the vagal tone in CD and IBS patients. Furthermore, they highlight the specific homeostatic link between vagal tone and TNF-alpha in CD and epinephrine in IBS and argue for the relevance of vagus nerve reinforcement interventions in those diseases.
Zhang, Yin; Venkitasamy, Chandrasekar; Pan, Zhongli; Liu, Wenlong; Zhao, Liming
Umami substances are very important for food seasoning and healthy eating. In addition to monosodium glutamate and some nucleotides, recent investigations have revealed that several peptides also exhibit umami taste. In recent years, 52 peptides have been reported to show umami taste, including 24 dipeptides, 16 tripeptides, 5 octapeptides, 2 pentapeptides, 2 hexapeptides, 1 tetrapeptide, 1 heptapeptide, and 1 undecapeptide. Twenty of these peptides have been examined for the present of umami taste. In this review, we have listed these umami peptides based on their category, source, taste, and threshold concentration. The evidence for peptides showing umami taste, the umami taste receptors on the human tongue, and the peptides whose umami taste is controversial are also discussed. © 2016 Institute of Food Technologists®.
Wistoft, Karen; Qvortrup, Lars
Aim: Traditionally and worldwide home economics education has been concerned with taste and flavorings based training associated with students cooking in the school kitchen. In contrast new educational research on food knowledge in the Danish public school shows that taste is used as a didactic...... for the different dimensions of taste education and their interrelations conceptualized as “structural couplings”. We characterize each of the dimensions based on a range of philosophical, theoretical and practical contributions, including concepts from the philosophy of aesthetics (Kant 1793), health education...... and practice, science, and moral philosophy. Results: The basic point is that “taste” is more than “tastiness”. According to our analysis, taste has four dimensions: 1) Taste is tastiness, i.e. a matter of aesthetics, 2) Taste is wellbeing, i.e. a matter of health, 3) Taste is something perceived, i...
Andy T. Woods
Full Text Available Recently, it has been demonstrated that people associate each of the basic tastes (e.g., sweet, sour, bitter, and salty with specific colors (e.g., red, green, black, and white. In the present study, we investigated whether pairs of colors (both associated with a particular taste or taste word would give rise to stronger associations relative to pairs of colors that were associated with different tastes. We replicate the findings of previous studies highlighting the existence of a robust crossmodal correspondence between individual colors and basic tastes. However, while there was evidence that pairs of colors could indeed communicate taste information more consistently than single colors, our participants took more than twice as long to match the color pairs with tastes than the single colors. Possible reasons for these results are discussed.
Perry, Nicole B.; Calkins, Susan D.; Nelson, Jackie A.; Leerkes, Esther M.; Marcovitch, Stuart
The current study examined the moderating effect of children’s cardiac vagal suppression on the association between maternal socialization of negative emotions (supportive and non-supportive responses) and children’s emotion regulation behaviors. One hundred and ninety-seven 4-year-olds and their mothers participated. Mothers reported on their reactions to children’s negative emotions and children’s regulatory behaviors. Observed distraction, an adaptive self-regulatory strategy, and vagal suppression were assessed during a laboratory task designed to elicit frustration. Results indicated that children’s vagal suppression moderated the association between mothers’ non-supportive emotion socialization and children’s emotion regulation behaviors such that non-supportive reactions to negative emotions predicted lower observed distraction and lower reported emotion regulation behaviors when children displayed lower levels of vagal suppression. No interaction was found between supportive maternal emotion socialization and vagal suppression for children’s emotion regulation behaviors. Results suggest physiological regulation may serve as a buffer against non-supportive emotion socialization. PMID:22072217
Yamashita, Atsuko; Kondo, Kaori; Kunishima, Yoshimi; Iseki, Sachiko; Kondo, Takashi; Ota, Masato S
Bitter taste avoidance behavior (BAB) plays a fundamental role in the avoidance of toxic substances with a bitter taste. However, the molecular basis underlying the development of BAB is unknown. To study critical developmental events by which taste buds turn into functional organs with BAB, we investigated the early phase development of BAB in postnatal mice in response to bitter-tasting compounds, such as quinine and thiamine. Postnatal mice started to exhibit BAB for thiamine and quinine at postnatal day 5 (PD5) and PD7, respectively. Histological analyses of taste buds revealed the formation of microvilli in the taste pores starting at PD5 and the localization of type 2 taste receptor 119 (TAS2R119) at the microvilli at PD6. Treatment of the tongue epithelium with cytochalasin D (CytD), which disturbs ACTIN polymerization in the microvilli, resulted in the loss of TAS2R119 localization at the microvilli and the loss of BAB for quinine and thiamine. The release of ATP from the circumvallate papillae tissue due to taste stimuli was also declined following CytD treatment. These results suggest that the localization of TAS2R119 at the microvilli of taste pores is critical for the initiation of BAB. Copyright © 2017 Elsevier Inc. All rights reserved.
Full Text Available Taste and olfaction are each tuned to a unique set of chemicals in the outside world, and their corresponding sensory spaces are mapped in different areas in the brain. This dichotomy matches categories of receptors detecting molecules either in the gaseous or in the liquid phase in terrestrial animals. However, in Drosophila olfactory and gustatory neurons express receptors which belong to the same family of 7-transmembrane domain proteins. Striking overlaps exist in their sequence structure and in their expression pattern, suggesting that there might be some functional commonalities between them. In this work, we tested the assumption that Drosophila olfactory receptor proteins are compatible with taste neurons by ectopically expressing an olfactory receptor (OR22a and OR83b for which ligands are known. Using electrophysiological recordings, we show that the transformed taste neurons are excited by odor ligands as by their cognate tastants. The wiring of these neurons to the brain seems unchanged and no additional connections to the antennal lobe were detected. The odor ligands detected by the olfactory receptor acquire a new hedonic value, inducing appetitive or aversive behaviors depending on the categories of taste neurons in which they are expressed i.e. sugar- or bitter-sensing cells expressing either Gr5a or Gr66a receptors. Taste neurons expressing ectopic olfactory receptors can sense odors at close range either in the aerial phase or by contact, in a lipophilic phase. The responses of the transformed taste neurons to the odorant are similar to those obtained with tastants. The hedonic value attributed to tastants is directly linked to the taste neurons in which their receptors are expressed.
Shoji, Noriaki; Satoh-Ku Riwada, Shizuko; Sasano, Takashi
Loss of umami taste sensation affects quality of life and causes weight loss and health problems, particularly in the elderly. We recently expanded the use of the filter paper disc method to include assessment of umami taste sensitivity, using monosodium glutamate as the test solution. This test showed high diagnostic performance for discriminating between normal taste function and disorders in sensation of the umami taste, according to established cut-off values. The test also revealed: (1) some elderly patients suffered from specific loss of umami taste sensation with preservation of the other four taste sensations (sweet, salty, sour, and bitter); (2) umami taste disorder caused a loss of appetite and decline in weight, resulting in poor health; (3) appetite, weight and overall health improved after appropriate treatment for umami taste disorder. Because of the subjective nature of the test, however, it may not be useful for patients who cannot express which taste sensation is induced by a tastant, such as those with dementia. Most recently, using tissue samples collected from the tongue by scraping the foliate papillae, we showed that evaluation of umami taste receptor gene expression may be clinically useful for the objective genetic diagnosis of umami taste disorders.
Gaillard, Dany; Stratford, Jennifer M
The natural like and dislike of foods based on taste is one of the most easily observed behaviors in animals. Animals eat palatable foods and reject aversive foods, which makes measurement of taste perception possible using various behavioral techniques. Three different methods to accurately measure taste behavior are described here. First, two-bottle preference tests evaluate whether a taste compound (tastant) is preferred over water. Second, lickometer tests quantify the like and dislike for multiple concentrations of the same tastant or multiple tastants at the same time. Finally, conditioned taste aversion tests accurately determine the perceived taste threshold for palatable tastants. Together, these diverse methods enable researchers to observe and measure behavioral taste responses in mice to any tastant. © 2016 by John Wiley & Sons, Inc. Copyright © 2016 John Wiley & Sons, Inc.
Lang, Ivan M.; Medda, Bidyut K.; Shaker, Reza
Esophageal mechanorecptors, i.e. muscular slowly adapting tension receptors and mucosal rapidly adapting touch receptors, mediate different sets of reflexes. The aim of this study was to determine the medullary vagal nuclei involved in the reflex responses to activation of these receptors. Thirty-three cats were anesthetized with alpha-chloralose and the esophagus was stimulated by slow balloon or rapid air distension. The physiological effects of the stimuli (N=4) were identified by recording responses from the pharyngeal, laryngeal, and hyoid muscles, esophagus, and the lower esophageal sphincter (LES). The effects on the medullary vagal nuclei of the stimuli: slow distension (N=10), rapid distension (N=9), and in control animals (N=10) were identified using the immunohistochemical analysis of c-fos. The experimental groups were stimulated 3 times per minute for 3 hours. After the experiment, the brains were removed and processed for c-fos immunoreactivity or thioinin. We found that slow balloon distension activated the esophago-UES contractile reflex and esophago LES relaxation response, and rapid air injection activated the belch and its component reflexes. Slow balloon distension activated the NTSce, NTSdl, NTSvl, DMNc, DMNr and NAr; and rapid air injection primarily activated AP, NTScd, NTSim, NTSis, NTSdm, NTSvl, NAc and NAr. We concluded that different sets of medullary vagal nuclei mediate different reflexes of the esophagus activated from different sets of mechanoreceptors. The NTScd is the primary NTS subnucleus mediating reflexes from the mucosal rapidly adapting touch receptors, and the NTSce is the primary NTS subnucleus mediating reflexes from the muscular slowly adapting tension receptors. The AP may be involved in mediation of belching. PMID:20971087
Hung, Ming-Hui; Hsu, Hsao-Hsun; Chan, Kuang-Cheng; Chen, Ke-Cheng; Yie, Jr-Chi; Cheng, Ya-Jung; Chen, Jin-Shing
Thoracoscopic surgery using internal intercostal nerve block, vagal block and targeted sedation without endotracheal intubation is a promising technique for selected patients, but little is known about its feasibility and safety. We evaluated 109 patients with lung (105), mediastinal (3) or pleural (1) tumours treated using non-intubated thoracoscopic surgery. Internal, intercostal nerve block was performed at the T3-T8 intercostal level and vagal block was performed adjacent to the vagus nerve at the level of the lower trachea for right-sided operations and at the level of the aortopulmonary window for left-sided operations. Sedation was performed with propofol infusion to achieve a bispectral index value between 40 and 60. Thoracoscopic lobectomy was performed in 43 patients, wedge resection in 50, segmentectomy in 12 and mediastinal or pleural tumour excision in 4. Three patients (2.8%) required conversion to intubated one-lung ventilation because of vigorous mediastinal movement and dense diaphragmatic adhesions. Anaesthetic induction and operation had a median duration of 10.0 and 127.0 min, respectively. Operative complications developed in 13 patients with air leaks for more than 3 days and 1 patient required transfusion of blood products. The median postoperative chest drainage and hospital stay were 2.0 and 4.0 days, respectively. Non-intubated thoracoscopic surgery using internal intercostal nerve block, vagal block and targeted sedation is technically feasible and safe in surgical treatment of lung, mediastinal and pleural tumours in selected patients. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
Yu, Xiaoyun; Hu, Youtian; Ru, Fei; Kollarik, Marian; Undem, Bradley J; Yu, Shaoyong
Sensory transduction in esophageal afferents requires specific ion channels and receptors. TRPM8 is a new member of the transient receptor potential (TRP) channel family and participates in cold- and menthol-induced sensory transduction, but its role in visceral sensory transduction is still less clear. This study aims to determine TRPM8 function and expression in esophageal vagal afferent subtypes. TRPM8 agonist WS-12-induced responses were first determined in nodose and jugular neurons by calcium imaging and then investigated by whole cell patch-clamp recordings in Dil-labeled esophageal nodose and jugular neurons. Extracellular single-unit recordings were performed in nodose and jugular C fiber neurons using ex vivo esophageal-vagal preparations with intact nerve endings in the esophagus. TRPM8 mRNA expression was determined by single neuron RT-PCR in Dil-labeled esophageal nodose and jugular neurons. The TRPM8 agonist WS-12 elicited calcium influx in a subpopulation of jugular but not nodose neurons. WS-12 activated outwardly rectifying currents in esophageal Dil-labeled jugular but not nodose neurons in a dose-dependent manner, which could be inhibited by the TRPM8 inhibitor AMTB. WS-12 selectively evoked action potential discharges in esophageal jugular but not nodose C fibers. Consistently, TRPM8 transcripts were highly expressed in esophageal Dil-labeled TRPV1-positive jugular neurons. In summary, the present study demonstrated a preferential expression and function of TRPM8 in esophageal vagal jugular but not nodose neurons and C fiber subtypes. This provides a distinctive role of TRPM8 in esophageal sensory transduction and may lead to a better understanding of the mechanisms of esophageal sensation and nociception. Copyright © 2015 the American Physiological Society.
Dyavanapalli, Jhansi; Jameson, Heather; Dergacheva, Olga; Jain, Vivek; Alhusayyen, Mona; Mendelowitz, David
Patients with obstructive sleep apnoea experience chronic intermittent hypoxia-hypercapnia (CIHH) during sleep that elicit sympathetic overactivity and diminished parasympathetic activity to the heart, leading to hypertension and depressed baroreflex sensitivity. The parasympathetic control of heart rate arises from pre-motor cardiac vagal neurons (CVNs) located in nucleus ambiguus (NA) and dorsal motor nucleus of the vagus (DMNX). The mechanisms underlying diminished vagal control of heart rate were investigated by studying the changes in blood pressure, heart rate, and neurotransmission to CVNs evoked by acute hypoxia-hypercapnia (H-H) and CIHH. In vivo telemetry recordings of blood pressure and heart rate were obtained in adult rats during 4 weeks of CIHH exposure. Retrogradely labelled CVNs were identified in an in vitro brainstem slice preparation obtained from adult rats exposed either to air or CIHH for 4 weeks. Postsynaptic inhibitory or excitatory currents were recorded using whole cell voltage clamp techniques. Rats exposed to CIHH had increases in blood pressure, leading to hypertension, and blunted heart rate responses to acute H-H. CIHH induced an increase in GABAergic and glycinergic neurotransmission to CVNs in NA and DMNX, respectively; and a reduction in glutamatergic neurotransmission to CVNs in both nuclei. CIHH blunted the bradycardia evoked by acute H-H and abolished the acute H-H evoked inhibition of GABAergic transmission while enhancing glycinergic neurotransmission to CVNs in NA. These changes with CIHH inhibit CVNs and vagal outflow to the heart, both in acute and chronic exposures to H-H, resulting in diminished levels of cardioprotective parasympathetic activity to the heart as seen in OSA patients. © 2014 The Authors. The Journal of Physiology © 2014 The Physiological Society.
Li, Wen; Chen, Zhe; Wu, Ruiqing; Zhang, Wenyan; Lu, Changli
To explore the clinical anatomy and the methods to protect or reconstruct the continuity and function of vagus nerve during the operation of cervical vagal paraganglioma. Six cases of vagal paraganglioma were reviewed. All tumors were identified to wrap the cervical vagus nerve stem and excised during surgery. The operative modality was to trace the vagus nerve stem inside the tumor as far as possible, to reconstruct the continuity by way of vagus nerve anastomosis (3/6) or alternatively, other motor nerve transplantation (3/6). Postoperative treatment included steroid, neurotrophic medication and voice and swallowing rehabilitation. Two cases of the recurrent paraganglioma experienced aspiration during swallowing preoperatively and no aspiration after surgery. Choking was gradually reduced in four recurrent cases half to one year postoperatively. Hoarseness was improved in five cases (5/6) half to one year postoperatively, while one case remained prolonged obvious hoarseness. Three months postoperatively, the vocal cord fibrillation at the tumor-related side was observed during pronunciation in the end-to-end anastomosis cases (3/6), sublingual nerve-transplanted case (1/6) and deep cervical nerve-transplanted cases (1/6) under fiberoptic laryngoscope, and the mobility was even more obvious at the time of half an year postoperatively. While in another deep cervical nerve-transplanted case (1/6), the vocal cord demonstrated no obvious fibrillation. To carefully identify and preserve the vagus nerve fibers as much as possible during the operation of cervical vagal paraganglioma could significantly eliminate postoperative hoarseness and aspiration. End-to-end anastomosis, deep cervical nerve or sublingual nerve transplantation to resume the continuity of vagus nerve may improve the mobility of vocal cord thus the quality of voice and swallowing.
Eser, Prisca; Herzig, David; Vogt, Marcel; Stämpfli, Roger; Trovato, Moreno; Olstad, Daniela Schäfer; Trachsel, Lukas; Deluigi, Christina; Wustmann, Kerstin; Greutmann, Matthias; Tobler, Daniel; Stambach, Dominik; Schmid, Jean-Paul; Schwerzmann, Markus; Wilhelm, Matthias
Patients with Fontan circulation have reduced heart rate variability (HRV) in supine position. However, neither cardiac autonomic nervous activity (CANA) in response to orthostatic challenge nor vagal reactivation by means of heart rate (HR) recovery after cessation of exercise have previously been investigated in Fontan patients. The aim of this study was to compare HRV in supine and standing position, as well as HR recovery between Fontan patients and healthy controls. Eight Fontan patients (4 male/4 female) without pacemakers and 12 healthy volunteers (5m/7f) with minimum age of 18years were recruited. HR was measured by Holter-electrocardiogram. HRV was measured in supine position and after orthostatic challenge. The power of the high frequency (HF: 0.15Hz-0.4Hz) and low frequency (LF: 0.04Hz-0.15Hz) bands was analysed by fast-Fourier transformation. HR recovery was determined at 30s and 60s after termination of a maximal exercise test. In both supine and standing position, total power, HF and LF power were reduced in Fontan patients compared to controls (by approximately a factor of 10) while there was no differences in LF/HF power ratio. Response to orthostatic challenge was blunted in absolute power but normal in relative power. HR recovery was not different between groups. Fontan patients have greatly reduced HRV, a blood-pressure dependent marker of CANA, but normal HR recovery, a blood pressure independent marker of vagal reactivation, suggesting that vagal activity may be normal, and only vascular capacitance reduced. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Yamakawa, S.; Yamaguchi, A. (Toyama National College of Maritime Technology, Toyama (Japan))
The present paper proposes a new taste recognition system using optical response patterns from multi-channel optical fiber sensors having potential sensitive dye coatings. It was found that the sensors give large changes in optical absorption spectra of the dyes when they are immersed in various taste solutions. Consequently, it was shown that the sensors can be used as a taste sensor. Six dyes, which give large changes in dye absorption, were selected from twenty dyes and used for six-channel optical fiber taste sensors array. The absorption spectra change data were processed by multiple discriminant analysis and neural networks using back-propagation algorithm. From the analytical results, it was demonstrated that salty (NaCl), bitter (quinidine), sweet (sucrose), sour (HCl), and umami (sodium glutamate) substances can be recognized from each other by using the optical taste sensor system. 11 refs., 8 figs., 2 tabs.
Aldskogius, H.; Barron, K.D.; Regal, R.
Pairs of adult rats received (/sup 3/H)leucine 0.25, 1, and 16 h before killing and zero to 164 days after unilateral cervical vagotomy and hypoglossal neurotomy. Grain counts and morphometric measurements were made on axotomized and uninjured neurons in histoautoradiographs of the medullary nuclei. Axotomized hypoglossal neurons, which largely survive the injury, both enlarged and incorporated increased amounts of tritiated leucine at each labeling interval, 3 through 28 days postoperatively. In the vagal dorsal motor nucleus (DMN), axotomized cells, which frequently die after neurotomy, enlarged slightly through 28 days postoperatively, then atrophied; DMN neurons increased amino acid uptake for a shorter period (days 7 through 14) than hypoglossal neurons. Axotomized DMN neurons did not sustain increased protein synthesis as long as their hypoglossal counterparts and seemed to fail to increase synthesis of structural proteins with long half-lives (16-h labeling interval). The frequently necrobiotic response of axotomized DMN neurons may relate to these phenomena. From these and earlier results, the authors conclude that axon reaction appears to differ fundamentally in peripheral and central neurons. This difference may have significance for research on regeneration in the central nervous system.
Kawasaki, Tatsuya; Sugihara, Hiroki
An abnormal blood pressure response to exercise has been reported to be associated with left ventricular subendocardial ischemia in patients with hypertrophic cardiomyopathy (HCM), but the underlying mechanism remains unclear. We report a case of HCM with an abnormal blood pressure response and subendocardial ischemia, in which the analysis of heart rate variability revealed exercise-induced vagal enhancement. The present case highlights the possible mechanism linking abnormal blood pressure response and left ventricular subendocardial ischemia in patients with HCM. ©2013 Wiley Periodicals, Inc.
Full Text Available Matheni Sathananthan,1 Sayeed Ikramuddin,2 James M Swain,3,6 Meera Shah,1 Francesca Piccinini,4 Chiara Dalla Man,4 Claudio Cobelli,4 Robert A Rizza,1 Michael Camilleri,5 Adrian Vella1 1Division of Endocrinology, Diabetes and Metabolism, Mayo Clinic College of Medicine, Rochester, MN, USA; 2Division of General Surgery, University of Minnesota, Minneapolis, MN, USA; 3Division of General Surgery, Mayo Clinic College of Medicine, Rochester, MN, USA; 4Department of Information Engineering, University of Padua, Padua, Italy; 5Division of Gastroenterology and Hepatology, Mayo Clinic College of Medicine, Rochester, MN, USA; 6Scottsdale Healthcare Bariatric Center, Scottsdale, AZ, USA Purpose: Vagal interruption causes weight loss in humans and decreases endogenous glucose production in animals. However, it is unknown if this is due to a direct effect on glucose metabolism. We sought to determine if vagal blockade using electrical impulses alters glucose metabolism in humans. Patients and methods: We utilized a randomized, cross-over study design where participants were studied after 2 weeks of activation or inactivation of vagal nerve blockade (VNB. Seven obese subjects with impaired fasting glucose previously enrolled in a long-term study to examine the effect of VNB on weight took part. We used a standardized triple-tracer mixed meal to enable measurement of the rate of meal appearance, endogenous glucose production, and glucose disappearance. The 550 kcal meal was also labeled with 111In-diethylene triamine pentaacetic acid (DTPA to measure gastrointestinal transit. Insulin action and ß-cell responsivity indices were estimated using the minimal model. Results: Integrated glucose, insulin, and glucagon concentrations did not differ between study days. This was also reflected in a lack of effect on β-cell responsivity and insulin action. Furthermore, fasting and postprandial endogenous glucose production, integrated meal appearance, and glucose
Mace, Oliver J; Affleck, Julie; Patel, Nick; Kellett, George L
Natural sugars and artificial sweeteners are sensed by receptors in taste buds. T2R bitter and T1R sweet taste receptors are coupled through G-proteins, α-gustducin and transducin, to activate phospholipase C β2 and increase intracellular calcium concentration. Intestinal brush cells or solitary chemosensory cells (SCCs) have a structure similar to lingual taste cells and strongly express α-gustducin. It has therefore been suggested over the last decade that brush cells may participate in sugar sensing by a mechanism analogous to that in taste buds. We provide here functional evidence for an intestinal sensing system based on lingual taste receptors. Western blotting and immunocytochemistry revealed that all T1R members are expressed in rat jejunum at strategic locations including Paneth cells, SCCs or the apical membrane of enterocytes; T1Rs are colocalized with each other and with α-gustducin, transducin or phospholipase C β2 to different extents. Intestinal glucose absorption consists of two components: one is classical active Na+–glucose cotransport, the other is the diffusive apical GLUT2 pathway. Artificial sweeteners increase glucose absorption in the order acesulfame potassium ∼ sucralose > saccharin, in parallel with their ability to increase intracellular calcium concentration. Stimulation occurs within minutes by an increase in apical GLUT2, which correlates with reciprocal regulation of T1R2, T1R3 and α-gustducin versus T1R1, transducin and phospholipase C β2. Our observation that artificial sweeteners are nutritionally active, because they can signal to a functional taste reception system to increase sugar absorption during a meal, has wide implications for nutrient sensing and nutrition in the treatment of obesity and diabetes. PMID:17495045
Thirumangalathu, Shoba; Barlow, Linda A.
The sense of taste is mediated by multicellular taste buds located within taste papillae on the tongue. In mice, individual taste buds reside in fungiform papillae, which develop at mid-gestation as epithelial placodes in the anterior tongue. Taste placodes comprise taste bud precursor cells, which express the secreted factor sonic hedgehog (Shh) and give rise to taste bud cells that differentiate around birth. We showed previously that epithelial activation of β-catenin is the primary induct...
James Paul Gee
Full Text Available In his entertaining 1986 book, The Real Coke, the Real Story, Thomas Oliver tells the story of the now infamous “New Coke”, a story retold in Malcolm Gladwell’s (2005 best-seller Blink. In the early 1980s, Pepsi began running commercials in which people took a sip from two glasses, not knowing which was Coke and which Pepsi. The majority preferred Pepsi. The Coca-Cola Company replicated these blind taste-tests and found the same result. Losing market share, Coke—long the dominant brand—changed its old formula and came out with “New Coke”, a soda made to a new formula, one that in a new round of blind taste-tests came out above Pepsi. But New Coke was a disaster.Consumers hated it. Coke not only returned to its old formula, but Pepsi never did overtake Coke, which remains today the dominant brand world-wide.
Kusuhara, Yoko; Yoshida, Ryusuke; Ohkuri, Tadahiro; Yasumatsu, Keiko; Voigt, Anja; Hübner, Sandra; Maeda, Katsumasa; Boehm, Ulrich; Meyerhof, Wolfgang; Ninomiya, Yuzo
The T1R1 receptor subunit acts as an umami taste receptor in combination with its partner, T1R3. In addition, metabotropic glutamate receptors (brain and taste variants of mGluR1 and mGluR4) are thought to function as umami taste receptors. To elucidate the function of T1R1 and the contribution of mGluRs to umami taste detection in vivo, we used newly developed knock-out (T1R1−/−) mice, which lack the entire coding region of the Tas1r1 gene and express mCherry in T1R1-expressing cells. Gustatory nerve recordings demonstrated that T1R1−/− mice exhibited a serious deficit in inosine monophosphate-elicited synergy but substantial residual responses to glutamate alone in both chorda tympani and glossopharyngeal nerves. Interestingly, chorda tympani nerve responses to sweeteners were smaller in T1R1−/− mice. Taste cell recordings demonstrated that many mCherry-expressing taste cells in T1R1+/− mice responded to sweet and umami compounds, whereas those in T1R1−/− mice responded to sweet stimuli. The proportion of sweet-responsive cells was smaller in T1R1−/− than in T1R1+/− mice. Single-cell RT-PCR demonstrated that some single mCherry-expressing cells expressed all three T1R subunits. Chorda tympani and glossopharyngeal nerve responses to glutamate were significantly inhibited by addition of mGluR antagonists in both T1R1−/− and T1R1+/− mice. Conditioned taste aversion tests demonstrated that both T1R1−/− and T1R1+/− mice were equally capable of discriminating glutamate from other basic taste stimuli. Avoidance conditioned to glutamate was significantly reduced by addition of mGluR antagonists. These results suggest that T1R1-expressing cells mainly contribute to umami taste synergism and partly to sweet sensitivity and that mGluRs are involved in the detection of umami compounds. PMID:23339178
Felipe eReinoso Carvalho
Full Text Available The soundscapes of those places where we eat and drink can influence our perception of taste. Here, we investigated whether contextual sound would enhance the subjective value of a tasting experience. The customers in a chocolate shop were invited to take part in an experiment in which they had to evaluate a chocolate’s taste while listening to an auditory stimulus. Four different conditions were presented to four different groups in a between-participants design. Envisioning a more ecological approach, a pre-recorded piece of popular music and the shop’s own soundscape were used as the sonic stimuli. The results revealed that not only did the customers report having a significantly better tasting experience when the sounds were presented as part of the food’s identity, but they were also willing to pay significantly more for the experience. The method outlined here paves a new approach to dealing with the design of multisensory tasting experiences, and gastronomic situations.
Rolls, Edmund T
The cortical processing of umami shows what makes it pleasant and appetitive. The pleasantness of umami reflects and is correlated with processing in the secondary taste cortex in the orbitofrontal cortex and tertiary taste cortex in the anterior cingulate cortex, whereas processing in the primary (insular) taste cortex reflects physical properties such as intensity. However, glutamate presented alone as a taste stimulus is not highly pleasant and does not act synergistically with other tastes (sweet, salt, bitter, and sour). When glutamate is given in combination with a consonant, savory odor (vegetable), the resulting flavor, formed by a convergence of the taste and olfactory pathways in the orbitofrontal cortex, can be much more pleasant. This pleasantness is shown by much greater activation of the medial orbitofrontal cortex and pregenual cingulate cortex than the sum of the activations by the taste and olfactory components presented separately. Furthermore, activations in these brain regions were correlated with the pleasantness and fullness of the flavor and with the consonance of the taste and olfactory components. The concept is proposed that umami can be thought of as a rich and delicious flavor that is produced by a combination of glutamate taste and a consonant savory odor. Glutamate is thus a flavor enhancer because of the way that it can combine supralinearly with consonant odors in cortical areas in which the taste and olfactory pathways converge far beyond the receptors. Cognitive and attentional modulation of the orbitofrontal cortex also contributes to the pleasantness and appetitive value of umami.
Shah, Mussadiq; Deeb, Jacquie; Fernando, Marina; Noyce, Alastair; Visentin, Elisa; Findley, Leslie J; Hawkes, Christopher H
Smell sense is impaired in classic Parkinson's disease (PD). An initial study found no change in taste threshold in non-demented PD subjects and pathological studies suggest that the first relay for taste, the nucleus of the solitary tract, is spared. We wished to determine if taste is abnormal in PD and whether it is associated with smell dysfunction. Taste threshold was estimated using the Rion electrogustometer and olfaction by the University of Pennsylvania Smell Identification Test (UPSIT) in 75 non-demented PD patients and 74 controls. There was a significant impairment of taste threshold and severe disorder of smell identification in the PD group. Age, duration of symptoms, disability, and smoking had no important effect on threshold measurement and there was no correlation between taste and smell dysfunction. Sensitivity analysis suggested that a provisional diagnosis of PD would be confirmed if smell or taste were abnormal; conversely, the diagnosis would merit review if both modalities were normal. Impaired taste appreciation was found in about 27% of patients with clinically defined PD. There were no important effects from age, disease severity or smell sense. Given the sparing of the first and second order taste neurones in PD, disorder of taste in PD most likely signifies involvement of the frontal operculum or orbitofrontal cortex, in keeping with advanced disease, although confounding by drug effects and changes in salivary constitution could not be excluded completely.
The molecular machinery for chemosensory transduction in taste buds has received considerable attention within the last decade. Consequently, we now know a great deal about sweet, bitter, and umami taste mechanisms and are gaining ground rapidly on salty and sour transduction. Sweet, bitter, and umami tastes are transduced by G-protein-coupled receptors. Salty taste may be transduced by epithelial Na channels similar to those found in renal tissues. Sour transduction appears to be initiated by intracellular acidification acting on acid-sensitive membrane proteins. Once a taste signal is generated in a taste cell, the subsequent steps involve secretion of neurotransmitters, including ATP and serotonin. It is now recognized that the cells responding to sweet, bitter, and umami taste stimuli do not possess synapses and instead secrete the neurotransmitter ATP via a novel mechanism not involving conventional vesicular exocytosis. ATP is believed to excite primary sensory afferent fibers that convey gustatory signals to the brain. In contrast, taste cells that do have synapses release serotonin in response to gustatory stimulation. The postsynaptic targets of serotonin have not yet been identified. Finally, ATP secreted from receptor cells also acts on neighboring taste cells to stimulate their release of serotonin. This suggests that there is important information processing and signal coding taking place in the mammalian taste bud after gustatory stimulation. PMID:17468883
Full Text Available Facial mimicry and vagal regulation represent two crucial physiological responses to others' facial expressions of emotions. Facial mimicry, defined as the automatic, rapid and congruent electromyographic activation to others' facial expressions, is implicated in empathy, emotional reciprocity and emotions recognition. Vagal regulation, quantified by the computation of Respiratory Sinus Arrhythmia (RSA, exemplifies the autonomic adaptation to contingent social cues. Although it has been demonstrated that childhood maltreatment induces alterations in the processing of the facial expression of emotions, both at an explicit and implicit level, the effects of maltreatment on children's facial mimicry and vagal regulation in response to facial expressions of emotions remain unknown. The purpose of the present study was to fill this gap, involving 24 street-children (maltreated group and 20 age-matched controls (control group. We recorded their spontaneous facial electromyographic activations of corrugator and zygomaticus muscles and RSA responses during the visualization of the facial expressions of anger, fear, joy and sadness. Results demonstrated a different impact of childhood maltreatment on facial mimicry and vagal regulation. Maltreated children did not show the typical positive-negative modulation of corrugator mimicry. Furthermore, when only negative facial expressions were considered, maltreated children demonstrated lower corrugator mimicry than controls. With respect to vagal regulation, whereas maltreated children manifested the expected and functional inverse correlation between RSA value at rest and RSA response to angry facial expressions, controls did not. These results describe an early and divergent functional adaptation to hostile environment of the two investigated physiological mechanisms. On the one side, maltreatment leads to the suppression of the spontaneous facial mimicry normally concurring to empathic understanding of
Katayama, Naomi; Space Agriculture Task Force; Nakata, Seiichi; Teranishi, Masaaki; Sone, Michihiko; Nakashima, Tsutomu; Hamajima, Nobuyuki; Ito, Yoshihiro
The sense of taste and smell come under some kind of influences in the space environment. In the space, the astronaut was changed their food habits from light taste and smell food to like strong taste and smells food. When an astronaut live in the space comes to have weak bone like osteoporosis. It may become the physiologic condition like the old man on the earth. Therefore this study performed fact-finding of the smell and the taste in the old man on the earth as test bed of astronaut in space. Based on this finding, it was intended to predict the taste and the olfactory change of the astronaut in the space. The study included 179 males and 251 females aged 30-90 years in Yakumo Town, Hokkaido, Japan. Odours were tested using a ``standard odours by odour stick identification''method of organoleptic testing. Taste were tested using a ``standard taste by taste disc identification'' method of chemical testing. Correct answers for identification odours consisted of average 6.0±3.0 in male subjects and average 6.9±2.8 in female subjects. Correct answers for identification of sweet taste consisted of 81% males and 87% females, salty taste consisted of 86% males and 91%, sour taste consisted of 75% males and 78% females, bitter taste consisted of 76% males and 88% females. It became clear that overall approximately 20% were in some kind of abnormality in sense of smell and taste. I want to perform the investigation that continued more in future.
Liang, Jie; Chen, Fuxue; Gu, Fu; Liu, Xin; Li, Feng; Du, Dongshu
The kidney is essential in the maintenance of in vivo homeostasis by body fluid and electrolyte conservation and metabolic waste removal. Previously, we reported the expression of a novel G protein family (Tas2rs), which includes bitter taste receptors, in the kidney tubule system, including the nephrons and the collecting duct system. Bitter taste receptors could affect kidney function via Ca(2+) intake. Alkaloids such as phenylthiocarbamide stimulate these receptors and cause an increase in Ca(2+) intake. In this study, we determined the expression of bitter taste receptors in the immature kidney and small intestine and in primary renal epithelial cells and M-1 (collecting tubule cell line) cells, by using QPCR and immunostaining. We found no expression of bitter taste receptors in the immature kidney and small intestine several days after birth; the relative abundance of Tas2rs transcripts varied depending on the developmental stage. Tas2rs were expressed in primary renal epithelial cells and M-1 cells. The traditional Chinese medicinal plant extracts phellodendrine and coptisine caused a rapid rise in intracellular Ca(2+) concentration, which was inhibited by the phospholipase C (PLC) inhibitor U-73122. Thus, phellodendrine and coptisine could change the physiological status of renal cells in vitro by mediation of bitter taste receptors in a PLC-dependent manner. Our results provide new insights on the expression and role of bitter taste receptors in renal development and function.
Full Text Available It is considered that memory consolidation is a progressive process that requires post-trial stabilization of the information. In this regard, it has been speculated that waves of receptors activation, expression of immediate early genes and replenishment of receptor subunit pools occur to induce functional or morphological changes to maintain the information for longer periods. In this paper, we will review data related to neuronal changes in the post-acquisition stage of taste aversion learning that could be involved in further stabilization of the memory trace. In order to achieve such stabilization, evidence suggests that the functional integrity of the insular cortex (IC and the amygdala (AMY is required. Particularly the increase of extracellular levels of glutamate and activation of N-methyl-D-aspartate (NMDA receptors within the IC shows a main role in the consolidation process. Additionally the modulatory actions of the dopaminergic system in the IC appear to be involved in the mechanisms that lead to taste aversion memory consolidation through the activation of pathways related to enhancement of protein synthesis such as the Protein Kinase A pathway. In summary, we suggest that post-acquisition molecular and neuronal changes underlying memory consolidation are dependent on the interactions between the AMY and the IC.
Full Text Available Popular science has emphasized the risks of high sodium intake and many studies have confirmed that salt intake is closely related to hypertension. The present mini-review summarizes experiments about salt taste sensitivity and its relationship with blood pressure (BP and other variables of clinical and familial relevance. Children and adolescents from control parents (N = 72 or with at least one essential hypertensive (EHT parent (N = 51 were investigated. Maternal questionnaires on eating habits and vomiting episodes were collected. Offspring, anthropometric, BP, and salt taste sensitivity values were recorded and blood samples analyzed. Most mothers declared that they added "little salt" when cooking. Salt taste sensitivity was inversely correlated with systolic BP (SBP in control youngsters (r = -0.33; P = 0.015. In the EHT group, SBP values were similar to control and a lower salt taste sensitivity threshold. Obese offspring of EHT parents showed higher SBP and C-reactive protein values but no differences in renin-angiotensin-aldosterone system activity. Salt taste sensitivity was correlated with SBP only in the non-obese EHT group (N = 41; r = 0.37; P = 0.02. Salt taste sensitivity was correlated with SBP in healthy, normotensive children and adolescents whose mothers reported significant vomiting during the first trimester (N = 18; r = -0.66; P < 0.005, but not in "non-vomiter offspring" (N = 54; r = -0.18; nonsignificant. There is evidence for a linkage between high blood pressure, salt intake and sensitivity, perinatal environment and obesity, with potential physiopathological implications in humans. This relationship has not been studied comprehensively using homogeneous methods and therefore more research is needed in this field.
Battjes-Fries, Marieke C E; Haveman-Nies, Annemien; Zeinstra, Gertrude G; van Dongen, Ellen J I; Meester, Hante J; van den Top-Pullen, Rinelle; Van't Veer, Pieter; de Graaf, Kees
This study assessed the effectiveness of the Dutch school programme Taste Lessons with and without additional experiential learning activities on children's willingness to taste unfamiliar vegetables. Thirty-three primary schools (877 children in grades 6-7 with a mean age of 10.3 years) participated in Taste Lessons Vegetable Menu (TLVM, lessons and extra activities), Taste Lessons (TL, lessons), or a control group. A baseline and follow-up measurement was used to assess for each child: number of four familiar and four unfamiliar vegetables tasted, quantity tasted, choice of vegetable of which to eat more, and number of vegetables willing to taste again later. Furthermore, children filled out a questionnaire on daily vegetable intake and food neophobia. Multilevel and Cox regression analyses were conducted to compare changes in the outcome measures between the three study groups. No significant intervention effects were found on willingness to taste unfamiliar vegetables. Neither were effects found on familiar vegetables, except for number of familiar vegetables tasted (p vegetable consumption and food neophobia. These results indicate that more intensive school-based nutrition education activities are needed to increase children's willingness to taste unfamiliar vegetables and increase their vegetable intake. Copyright © 2016. Published by Elsevier Ltd.
Wilson, Courtney E; Finger, Thomas E; Kinnamon, Sue C
Activation of Type III cells in mammalian taste buds is implicated in the transduction of acids (sour) and salty stimuli. Several lines of evidence suggest that function of Type III cells in the anterior taste fields may differ from that of Type III cells in posterior taste fields. Underlying anatomy to support this observation is, however, scant. Most existing immunohistochemical data characterizing this cell type focus on circumvallate taste buds in the posterior tongue. Equivalent data from anterior taste fields-fungiform papillae and soft palate-are lacking. Here, we compare Type III cells in four taste fields: fungiform, soft palate, circumvallate, and foliate in terms of reactivity to four canonical markers of Type III cells: polycystic kidney disease 2-like 1 (PKD2L1), synaptosomal associated protein 25 (SNAP25), serotonin (5-HT), and glutamate decarboxylase 67 (GAD67). Our findings indicate that while PKD2L1, 5-HT, and SNAP25 are highly coincident in posterior taste fields, they diverge in anterior taste fields. In particular, a subset of taste cells expresses PKD2L1 without the synaptic markers, and a subset of SNAP25 cells lacks expression of PKD2L1. In posterior taste fields, GAD67-positive cells are a subset of PKD2L1 expressing taste cells, but anterior taste fields also contain a significant population of GAD67-only expressing cells. These differences in expression patterns may underlie the observed functional differences between anterior and posterior taste fields. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: firstname.lastname@example.org.
Nicole L. Garneau
Full Text Available Understanding the influence of taste perception on food choice has captured the interest of academics, industry, and the general public. The latter as evidenced by the extent of popular media coverage and use of the term supertaster. Supertasters are highly sensitive to the bitter tastant propylthiouracil (PROP and its chemical relative phenylthiocarbamide. The well-researched differences in taste sensitivity to these bitter chemicals are partially controlled by variation in the TAS2R38 gene; however this variation alone does not explain the supertaster phenomenon. It has been suggested that density of papillae, which house taste buds, may explain supertasting. To address the unresolved role of papillae, we used crowdsourcing in the museum-based Genetics of Taste Lab. This community lab is uniquely situated to attract both a large population of human subjects and host a team of citizen scientists to research population-based questions about human genetics, taste, and health. Using this model, we find that PROP bitterness is not in any way predicted by papillae density. This result holds within the whole sample, when divided into major diplotypes, and when correcting for age, sex, and genotype. Furthermore, it holds when dividing participants into oft-used taster status groups. These data argue against the use of papillae density in predicting taste sensitivity and caution against imprecise use of the term supertaster. Furthermore, it supports a growing volume of evidence that sets the stage for hyperguesia, a reconceptualization of heightened oral sensitivity that is not based solely on PROP or papillae density. Finally, our model demonstrates how community-based research can serve as a unique venue for both study participation and citizen science that makes scientific research accessible and relevant to people’s everyday lives.
Garneau, Nicole L.; Nuessle, Tiffany M.; Sloan, Meghan M.; Santorico, Stephanie A.; Coughlin, Bridget C.; Hayes, John E.
Understanding the influence of taste perception on food choice has captured the interest of academics, industry, and the general public, the latter as evidenced by the extent of popular media coverage and use of the term supertaster. Supertasters are highly sensitive to the bitter tastant propylthiouracil (PROP) and its chemical relative phenylthiocarbamide. The well-researched differences in taste sensitivity to these bitter chemicals are partially controlled by variation in the TAS2R38 gene; however, this variation alone does not explain the supertaster phenomenon. It has been suggested that density of papillae, which house taste buds, may explain supertasting. To address the unresolved role of papillae, we used crowdsourcing in the museum-based Genetics of Taste Lab. This community lab is uniquely situated to attract both a large population of human subjects and host a team of citizen scientists to research population-based questions about human genetics, taste, and health. Using this model, we find that PROP bitterness is not in any way predicted by papillae density. This result holds within the whole sample, when divided into major diplotypes, and when correcting for age, sex, and genotype. Furthermore, it holds when dividing participants into oft-used taster status groups. These data argue against the use of papillae density in predicting taste sensitivity and caution against imprecise use of the term supertaster. Furthermore, it supports a growing volume of evidence that sets the stage for hypergeusia, a reconceptualization of heightened oral sensitivity that is not based solely on PROP or papillae density. Finally, our model demonstrates how community-based research can serve as a unique venue for both study participation and citizen science that makes scientific research accessible and relevant to people’s everyday lives. PMID:24904324
Full Text Available Paragangliomas are rare tumors and very few cases of malignant vagal paraganglioma with synchronous carotid body paraganglioma have been reported. We report a case of a 20-year old male who presented with slow growing bilateral neck masses of eight years duration. He had symptoms of dysphagia to solids, occasional mouth breathing and hoarseness of voice. Fine needle aspiration cytology (FNAC performed where he lived showed a sinus histiocytosis and he was administered anti-tubercular treatment for six months without any improvement in his symptoms. His physical examination revealed pulsatile, soft to firm, non-tender swellings over the anterolateral neck confined to the upper-mid jugulo-diagastric region on both sides. Direct laryngoscopy examination revealed a bulge on the posterior pharyngeal wall and another over the right lateral pharyngeal wall. Magnetic resonance imaging (MRI, 99mTc-labeled octreotide scan and angiography diagnosed the swellings as carotid body paraganglioma, stage III on the right side with left-sided vagal malignant paraganglioma. Surgery was ruled out as a high morbidity with additional risk to life was expected due to the highly vascular nature of the tumor. The patient was treated with radiation therapy by image guided radiation to a dose of 5040cGy in 28 fractions. At a follow-up at 16 months, the tumors have regressed bilaterally and the patient can take solids with ease.
de Lartigue, Guillaume; Ronveaux, Charlotte C; Raybould, Helen E
The vagal afferent pathway senses hormones released from the gut in response to nutritional cues and relays these signals to the brain. We tested the hypothesis that leptin resistance in vagal afferent neurons (VAN) is responsible for the onset of hyperphagia by developing a novel conditional knockout mouse to delete leptin receptor selectively in sensory neurons (Nav1.8/LepR (fl/fl) mice). Chow fed Nav1.8/LepR (fl/fl) mice weighed significantly more and had increased adiposity compared with wildtype mice. Cumulative food intake, meal size, and meal duration in the dark phase were increased in Nav1.8/LepR (fl/fl) mice; energy expenditure was unaltered. Reduced satiation in Nav1.8/LepR (fl/fl) mice is in part due to reduced sensitivity of VAN to CCK and the subsequent loss of VAN plasticity. Crucially Nav1.8/LepR (l/fl) mice did not gain further weight in response to a high fat diet. We conclude that disruption of leptin signaling in VAN is sufficient and necessary to promote hyperphagia and obesity.
Ghali, Michael George Zaki
Respiration consists of three phases--inspiration (I), post-inspiration (post-I), and late expiration (E2). Pre-I is a subphase occurring at the end of E2. Hypoglossal (XII) discharge contains I and occasionally pre-I activity. Functionally, XII pre-I underlies tongue muscle contraction and expansion of the upper airway, causing a decrease in airway resistance in anticipation of the succeeding inspiratory effort. It has been shown that vagotomy causes an increase in pre-I activity in XII in anesthetized animals. Also, in anesthetized artificially-ventilated animals, XII onset is synchronized with that of inspiratory phrenic nerve (PhN) activity. Therefore, we sought to systematically test the hypothesis that XII pre-I is present in vagus-intact unanesthetized decerebrate animals and vagal afferents negatively modulate XII pre-I discharge in decerebrate rats, in the absence of confounding anesthesia. Experiments were performed on seven Sprague-Dawley unanesthetized decerebrate adult male rats and bilateral PhN and XII recordings performed. In three animals, vagotomy was performed during PhN recordings and one animal was vagotomized during initial surgical preparation prior to recordings. In vagus-intact animals, XII pre-I duration averaged 12.4 ms. Vagotomy was associated with greater XII pre-I duration, expressed in absolute time (89.5 vs. 12.4 ms; pdecerebrate animals and is negatively modulated by vagal afferents. Copyright © 2015 Elsevier B.V. All rights reserved.
Diaz, V; Arsenault, J; Praud, J P
The aim of this study was to test the hypothesis that capsaicin treatment in lambs selectively inhibits bronchopulmonary C-fiber function but does not alter other vagal pulmonary receptor functions or peripheral and central chemoreceptor functions. Eleven lambs were randomized to receive a subcutaneous injection of either 25 mg/kg capsaicin (6 lambs) or solvent (5 lambs) under general anesthesia. Capsaicin-treated lambs did not demonstrate the classical ventilatory response consistently observed in response to capsaicin bolus intravenous injection in control lambs. Moreover, the ventilatory responses to stimulation of the rapidly adapting pulmonary stretch receptors (intratracheal water instillation) and slowly adapting pulmonary stretch receptors (Hering-Breuer inflation reflex) were similar in both groups of lambs. Finally, the ventilatory responses to various stimuli and depressants of carotid body activity and to central chemoreceptor stimulation (CO(2) rebreathing) were identical in control and capsaicin-treated lambs. We conclude that 25 mg/kg capsaicin treatment in lambs selectively inhibits bronchopulmonary C-fiber function without significantly affecting the other vagal pulmonary receptor functions or that of peripheral and central chemoreceptors.
Phillips, Robert J; Walter, Gary C; Powley, Terry L
Recent progress in understanding visceral afferents, some of it reviewed in the present issue, serves to underscore how little is known about the aging of the visceral afferents in the gastrointestinal (GI) tract. In spite of the clinical importance of the issue-with age, GI function often becomes severely compromised-only a few initial observations on age-related structural changes of visceral afferents are available. Primary afferent cell bodies in both the nodose ganglia and dorsal root ganglia lose Nissl material and accumulate lipofucsin, inclusions, aggregates, and tangles. Additionally, in changes that we focus on in the present review, vagal visceral afferent terminals in both the muscle wall and the mucosa of the GI tract exhibit age-related structural changes. In aged animals, both of the vagal terminal types examined, namely intraganglionic laminar endings and villus afferents, exhibit dystrophic or regressive morphological changes. These neuropathies are associated with age-related changes in the structural integrity of the target organs of the affected afferents, suggesting that local changes in trophic environment may give rise to the aging of GI innervation. Given the clinical relevance of GI tract aging, a more complete understanding both of how aging alters the innervation of the gut and of how such changes might be mitigated should be made research priorities. Copyright 2009 Elsevier B.V. All rights reserved.
Vissink, A; Jager-Wittenaar, H; Visser, A; Spijkervet, F K L; van Weissenbruch, R; van Nieuw Amerongen, A
Taste and smell perception are closely related. The taste perception is performed by taste buds which can distinguish salt, sour, sweet, bitter, and umami. Moreover, 2,000-4,000 smells can be recognized. Many taste disorders are in fact smell disorders. Saliva affects taste perception because it serves as a solvent for taste substances and as a protecting agent for the taste receptors. Therefore, hyposalivation leads to a reduction in taste perception, in which the concentration of zinc ions and specific proteins in saliva play an important role. In addition, zinc and iron deficiencies may cause diminished taste and smell perception.
Damon G. Lamb
Full Text Available Posttraumatic stress disorder (PTSD is a reaction to trauma that results in a chronic perception of threat, precipitating mobilization of the autonomic nervous system, and may be reflected by chronic disinhibition of limbic structures. A common injury preceding PTSD in veterans is mild traumatic brain injury (mTBI. This may be due to the vulnerability of white matter in these networks and such damage may affect treatment response. We evaluated transcutaneous vagal nerve stimulation (tVNS, a non-invasive, low-risk approach that may alter the functions of the limbo-cortical and peripheral networks underlying the hyperarousal component of PTSD and thus improve patient health and well-being. In this single visit pilot study evaluating the impact of tVNS in 22 combat veterans, we used a between-subjects design in people with either PTSD with preceding mTBI or healthy controls. Participants were randomized into stimulation or sham groups and completed a posturally modulated autonomic assessment and emotionally modulated startle paradigm. The primary measures used were respiratory sinus arrhythmia (high-frequency heart rate variability during a tilt-table procedure derived from an electrocardiogram, and skin conductance changes in response to acoustic startle while viewing emotional images (International Affective Picture System. The stimulation was well tolerated and resulted in improvements in vagal tone and moderation of autonomic response to startle, consistent with modulation of autonomic state and response to stress in this population. Our results suggest that tVNS affects systems underlying emotional dysregulation in this population and, therefore, should be further evaluated and developed as a potential treatment tool for these patients.
Takagi, Keisuke; Hirata, Takamichi; Akiya, Masahiro
A taste sensor consisting of a back-gate type field effect transistor(FET) chip based on carbon nanotube compound materials[poly(ethylene glycol)(PEG)-grafted single-walled carbon nanotubes(PEG-SWNTs)] was developed. The results of impedance measurements for five tastes (sourness, saltiness, bitterness, sweetness, and umami), are shown much difference for specific tastes which are difficult to identify by using Langmuir-Blodgett(LB)film. Moreover, the sensor is able to distinguish most of the experimental taste materials with a short response time. Characteristics of the sensor involve in taste material concentration , initial impedance and frequency characteristics. A clear difference is observed over five basic taste materials.
Murakami, Yuzuru; Sera, Koshi; Nagasawa, Hiroshi; Fukushima, Noriyuki; Yajin, Koji; Harada, Yasuo (Hiroshima Univ. (Japan). School of Medicine)
Qualitative gustometry (filter paper disc method) was performed in six patients who underwent radiation therapy. Following results were obtained. 1) Subjective taste disturbance appeared when irradiation dosage amounted to 1000-2000 rad. Whereas, it disappeared in 1 to 3 months after the termination of irradiation. 2) The longer the period of irradiation, the more slowly taste disturbance recovered. 3) Disgeusia was noticed in 44.3% of S, 66.7% of N, 70% of T and 36.2% of Q tests. 4) Taste thresholds in the apical tongue region improved almost parallel to subjective recovery of the taste. Occasionally taste disturbance was prolonged over a month. This is possibly due to delayed regeneration of the gustatory buds. Furthermore, conditions of the oral cavity, such as infection, or mechanical stimulation, may well influence degree of taste disturbance and the process of regeneration.
Chen, Qing-Ying; Alarcon, Suzanne; Tharp, Anilet; Ahmed, Osama M; Estrella, Nelsa L; Greene, Tiffani A; Rucker, Joseph; Breslin, Paul AS
Background: The TAS1R1 and TAS1R3 G protein–coupled receptors are believed to function in combination as a heteromeric glutamate taste receptor in humans. Objective: We hypothesized that variations in the umami perception of glutamate would correlate with variations in the sequence of these 2 genes, if they contribute directly to umami taste. Design: In this study, we first characterized the general sensitivity to glutamate in a sample population of 242 subjects. We performed these experiments by sequencing the coding regions of the genomic TAS1R1 and TAS1R3 genes in a separate set of 87 individuals who were tested repeatedly with monopotassium glutamate (MPG) solutions. Last, we tested the role of the candidate umami taste receptor hTAS1R1-hTAS1R3 in a functional expression assay. Results: A subset of subjects displays extremes of sensitivity, and a battery of different psychophysical tests validated this observation. Statistical analysis showed that the rare T allele of single nucleotide polymorphism (SNP) R757C in TAS1R3 led to a doubling of umami ratings of 25 mmol MPG/L. Other suggestive SNPs of TAS1R3 include the A allele of A5T and the A allele of R247H, which both resulted in an approximate doubling of umami ratings of 200 mmol MPG/L. We confirmed the potential role of the human TAS1R1-TAS1R3 heteromer receptor in umami taste by recording responses, specifically to l-glutamate and inosine 5′-monophosphate (IMP) mixtures in a heterologous expression assay in HEK (human embryonic kidney) T cells. Conclusions: There is a reliable and valid variation in human umami taste of l-glutamate. Variations in perception of umami taste correlated with variations in the human TAS1R3 gene. The putative human taste receptor TAS1R1-TAS1R3 responds specifically to l-glutamate mixed with the ribonucleotide IMP. Thus, this receptor likely contributes to human umami taste perception. PMID:19587085
Chen, Qing-Ying; Alarcon, Suzanne; Tharp, Anilet; Ahmed, Osama M; Estrella, Nelsa L; Greene, Tiffani A; Rucker, Joseph; Breslin, Paul A S
The TAS1R1 and TAS1R3 G protein-coupled receptors are believed to function in combination as a heteromeric glutamate taste receptor in humans. We hypothesized that variations in the umami perception of glutamate would correlate with variations in the sequence of these 2 genes, if they contribute directly to umami taste. In this study, we first characterized the general sensitivity to glutamate in a sample population of 242 subjects. We performed these experiments by sequencing the coding regions of the genomic TAS1R1 and TAS1R3 genes in a separate set of 87 individuals who were tested repeatedly with monopotassium glutamate (MPG) solutions. Last, we tested the role of the candidate umami taste receptor hTAS1R1-hTAS1R3 in a functional expression assay. A subset of subjects displays extremes of sensitivity, and a battery of different psychophysical tests validated this observation. Statistical analysis showed that the rare T allele of single nucleotide polymorphism (SNP) R757C in TAS1R3 led to a doubling of umami ratings of 25 mmol MPG/L. Other suggestive SNPs of TAS1R3 include the A allele of A5T and the A allele of R247H, which both resulted in an approximate doubling of umami ratings of 200 mmol MPG/L. We confirmed the potential role of the human TAS1R1-TAS1R3 heteromer receptor in umami taste by recording responses, specifically to l-glutamate and inosine 5'-monophosphate (IMP) mixtures in a heterologous expression assay in HEK (human embryonic kidney) T cells. There is a reliable and valid variation in human umami taste of l-glutamate. Variations in perception of umami taste correlated with variations in the human TAS1R3 gene. The putative human taste receptor TAS1R1-TAS1R3 responds specifically to l-glutamate mixed with the ribonucleotide IMP. Thus, this receptor likely contributes to human umami taste perception.
Kolkka-Palomaa, M; Jääskeläinen, S K; Laine, M A; Teerijoki-Oksa, T; Sandell, M; Forssell, H
Primary burning mouth syndrome (BMS) is a chronic oral condition characterized by burning pain often accompanied with taste dysfunction and xerostomia. The most compelling evidence concerning BMS pathophysiology comes from studies on the somatosensory system using neurophysiologic or psychophysical methods such as blink reflex, thermal quantitative sensory testing, as well as functional brain imaging. They have provided convincing evidence for neuropathic involvement at several levels of the somatosensory system in BMS pain pathophysiology. The number of taste function studies trying to substantiate the subjective taste disturbances or studies on salivary factors in BMS is much more limited, and most of them suffer from definitional and methodological problems. This review aims to critically evaluate the existing literature on the pathophysiology of BMS, paying special attention to the correctness of case selection and the methodology used in published studies, and to summarize the current state of knowledge. Based on the recognition of several gaps in the current understanding of the pathophysiology of BMS especially as regards taste and pain system interactions, the review ends with future scenarios for research in this area. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Sen, Tanusree; Cawthon, Carolina R; Ihde, Benjamin Thomas; Hajnal, Andras; DiLorenzo, Patricia M; de La Serre, Claire B; Czaja, Krzysztof
Obesity is one of the major health issues in the United States. Consumption of diets rich in energy, notably from fats and sugars (high-fat/high-sugar diet: HF/HSD) is linked to the development of obesity and a popular dietary approach for weight loss is to reduce fat intake. Obesity research traditionally uses low and high fat diets and there has been limited investigation of the potential detrimental effects of a low-fat/high-sugar diet (LF/HSD) on body fat accumulation and health. Therefore, in the present study, we investigated the effects of HF/HSD and LF/HSD on microbiota composition, gut inflammation, gut-brain vagal communication and body fat accumulation. Specifically, we tested the hypothesis that LF/HSD changes the gut microbiota, induces gut inflammation and alters vagal gut-brain communication, associated with increased body fat accumulation. Sprague-Dawley rats were fed an HF/HSD, LF/HSD or control low-fat/low-sugar diet (LF/LSD) for 4weeks. Body weight, caloric intake, and body composition were monitored daily and fecal samples were collected at baseline, 1, 6 and 27days after the dietary switch. After four weeks, blood and tissues (gut, brain, liver and nodose ganglia) were sampled. Both HF/HSD and LF/HSD-fed rats displayed significant increases in body weight and body fat compared to LF/LSD-fed rats. 16S rRNA sequencing showed that both HF/HSD and LF/HSD-fed animals exhibited gut microbiota dysbiosis characterized by an overall decrease in bacterial diversity and an increase in Firmicutes/Bacteriodetes ratio. Dysbiosis was typified by a bloom in Clostridia and Bacilli and a marked decrease in Lactobacillus spp. LF/HSD-fed animals showed a specific increase in Sutterella and Bilophila, both Proteobacteria, abundances of which have been associated with liver damage. Expression of pro-inflammatory cytokines, such as IL-6, IL-1β and TNFα, was upregulated in the cecum while levels of tight junction protein occludin were downregulated in both HF
Tauber, John M; Brown, Elizabeth B; Li, Yuanyuan; Yurgel, Maria E; Masek, Pavel; Keene, Alex C
Fat represents a calorically potent food source that yields approximately twice the amount of energy as carbohydrates or proteins per unit of mass. The highly palatable taste of free fatty acids (FAs), one of the building blocks of fat, promotes food consumption, activates reward circuitry, and is thought to contribute to hedonic feeding underlying many metabolism-related disorders. Despite a role in the etiology of metabolic diseases, little is known about how dietary fats are detected by the gustatory system to promote feeding. Previously, we showed that a broad population of sugar-sensing taste neurons expressing Gustatory Receptor 64f (Gr64f) is required for reflexive feeding responses to both FAs and sugars. Here, we report a genetic silencing screen to identify specific populations of taste neurons that mediate fatty acid (FA) taste. We find neurons identified by expression of Ionotropic Receptor 56d (IR56d) are necessary and sufficient for reflexive feeding response to FAs. Functional imaging reveals that IR56d-expressing neurons are responsive to short- and medium-chain FAs. Silencing IR56d neurons selectively abolishes FA taste, and their activation is sufficient to drive feeding responses. Analysis of co-expression with Gr64f identifies two subpopulations of IR56d-expressing neurons. While physiological imaging reveals that both populations are responsive to FAs, IR56d/Gr64f neurons are activated by medium-chain FAs and are sufficient for reflexive feeding response to FAs. Moreover, flies can discriminate between sugar and FAs in an aversive taste memory assay, indicating that FA taste is a unique modality in Drosophila. Taken together, these findings localize FA taste within the Drosophila gustatory center and provide an opportunity to investigate discrimination between different categories of appetitive tastants.
John M Tauber
Full Text Available Fat represents a calorically potent food source that yields approximately twice the amount of energy as carbohydrates or proteins per unit of mass. The highly palatable taste of free fatty acids (FAs, one of the building blocks of fat, promotes food consumption, activates reward circuitry, and is thought to contribute to hedonic feeding underlying many metabolism-related disorders. Despite a role in the etiology of metabolic diseases, little is known about how dietary fats are detected by the gustatory system to promote feeding. Previously, we showed that a broad population of sugar-sensing taste neurons expressing Gustatory Receptor 64f (Gr64f is required for reflexive feeding responses to both FAs and sugars. Here, we report a genetic silencing screen to identify specific populations of taste neurons that mediate fatty acid (FA taste. We find neurons identified by expression of Ionotropic Receptor 56d (IR56d are necessary and sufficient for reflexive feeding response to FAs. Functional imaging reveals that IR56d-expressing neurons are responsive to short- and medium-chain FAs. Silencing IR56d neurons selectively abolishes FA taste, and their activation is sufficient to drive feeding responses. Analysis of co-expression with Gr64f identifies two subpopulations of IR56d-expressing neurons. While physiological imaging reveals that both populations are responsive to FAs, IR56d/Gr64f neurons are activated by medium-chain FAs and are sufficient for reflexive feeding response to FAs. Moreover, flies can discriminate between sugar and FAs in an aversive taste memory assay, indicating that FA taste is a unique modality in Drosophila. Taken together, these findings localize FA taste within the Drosophila gustatory center and provide an opportunity to investigate discrimination between different categories of appetitive tastants.
Lossow, Kristina; Hübner, Sandra; Roudnitzky, Natacha; Slack, Jay P.; Pollastro, Federica; Behrens, Maik; Meyerhof, Wolfgang
One key to animal survival is the detection and avoidance of potentially harmful compounds by their bitter taste. Variable numbers of taste 2 receptor genes expressed in the gustatory end organs enable bony vertebrates (Euteleostomi) to recognize numerous bitter chemicals. It is believed that the receptive ranges of bitter taste receptor repertoires match the profiles of bitter chemicals that the species encounter in their diets. Human and mouse genomes contain pairs of orthologous bitter receptor genes that have been conserved throughout evolution. Moreover, expansions in both lineages generated species-specific sets of bitter taste receptor genes. It is assumed that the orthologous bitter taste receptor genes mediate the recognition of bitter toxins relevant for both species, whereas the lineage-specific receptors enable the detection of substances differently encountered by mice and humans. By challenging 34 mouse bitter taste receptors with 128 prototypical bitter substances in a heterologous expression system, we identified cognate compounds for 21 receptors, 19 of which were previously orphan receptors. We have demonstrated that mouse taste 2 receptors, like their human counterparts, vary greatly in their breadth of tuning, ranging from very broadly to extremely narrowly tuned receptors. However, when compared with humans, mice possess fewer broadly tuned receptors and an elevated number of narrowly tuned receptors, supporting the idea that a large receptor repertoire is the basis for the evolution of specialized receptors. Moreover, we have demonstrated that sequence-orthologous bitter taste receptors have distinct agonist profiles. Species-specific gene expansions have enabled further diversification of bitter substance recognition spectra. PMID:27226572
Wang, Qian Janice; Wang, Sheila; Spence, Charles
People intuitively match basic tastes to sounds of different pitches, and the matches that they make tend to be consistent across individuals. It is, though, not altogether clear what governs such crossmodal mappings between taste and auditory pitch. Here, we assess whether variations in taste intensity influence the matching of taste to pitch as well as the role of emotion in mediating such crossmodal correspondences. Participants were presented with 5 basic tastants at 3 concentrations. In Experiment 1, the participants rated the tastants in terms of their emotional arousal and valence/pleasantness, and selected a musical note (from 19 possible pitches ranging from C2 to C8) and loudness that best matched each tastant. In Experiment 2, the participants made emotion ratings and note matches in separate blocks of trials, then made emotion ratings for all 19 notes. Overall, the results of the 2 experiments revealed that both taste quality and concentration exerted a significant effect on participants' loudness selection, taste intensity rating, and valence and arousal ratings. Taste quality, not concentration levels, had a significant effect on participants' choice of pitch, but a significant positive correlation was observed between individual perceived taste intensity and pitch choice. A significant and strong correlation was also demonstrated between participants' valence assessments of tastants and their valence assessments of the best-matching musical notes. These results therefore provide evidence that: 1) pitch-taste correspondences are primarily influenced by taste quality, and to a lesser extent, by perceived intensity; and 2) such correspondences may be mediated by valence/pleasantness. © The Author 2016. Published by Oxford University Press.
Two generations of gustatory organs occur during amphibian ontogeny in frogs and salamanders (Anura and Caudata), and are classified as taste buds or taste discs. Taste buds are present in larval forms, whereas taste discs are typical for adults. The little research done on Gymnophiona suggests that only taste buds are ...
Perna Marla K
and tissue disruption seen in certain developing p27Kip1-null sensory organs, and may reflect a compensatory capability inherent in the regenerative taste system.
Harrison, Theresa A; Smith Adams, Lorraine B; Moore, Preston D; Perna, Marla K; Sword, Jarrod D; Defoe, Dennis M
-null sensory organs, and may reflect a compensatory capability inherent in the regenerative taste system.
Sodium appetite appears to be an excellent model to study the neural mechanisms of motivation. In this issue of Chemical Senses, experiments by St John (2016) challenge 2 hypotheses for how a systemic sodium deficit guides an animal to find and ingest more Na ions in the environment. Both hypotheses deal with modifications of the sensory neural code produced by Na(+) ions on the tongue. One envisions a change in the Na(+) signal amplitude. A reduction could make the strong Na(+) signals less aversive; an increase, weak signals more noticeable. The other hypothesis requires no changes in the identity or amplitude of the Na(+) signal, but a shift in its hedonic tone toward sweetness or reward. The results of the 3 behavioral experiments render both explanations unlikely but fail to suggest alternatives. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: email@example.com.
Chaudhari, Nirupa; Pereira, Elizabeth; Roper, Stephen D
Umami taste is elicited by many small molecules, including amino acids (glutamate and aspartate) and nucleotides (monophosphates of inosinate or guanylate, inosine 5′-monophosphate and guanosine-5′-monophosphate). Mammalian taste buds respond to these diverse compounds via membrane receptors that bind the umami tastants. Over the past 15 y, several receptors have been proposed to underlie umami detection in taste buds. These receptors include 2 glutamate-selective G protein–coupled receptors,...
森谷, 哲朗; 矢野, 博明; 岩田, 洋夫
This paper describes sensory integration using the Food Simulator. A taste of a food arises from mixture of auditory, chemical, and force sensation. The food simulator generates a food texture according to the force profile captured from a user's biting force of a real food. By development of the Food Simulator, we can extract only texture from taste. We experimented in sensory integration by displaying texture, sound, smell and taste. Our goal is to study integration among sensory modalities...
Lynch, Katherine E; Lynch, Rebecca; Curhan, Gary C; Brunelli, Steven M
The objective of this study was to examine the association between altered taste perception and nutritional status among hemodialysis patients. We performed a post hoc analysis of data from the Hemodialysis study (n = 1,745). Taste perception was assessed at baseline and then updated annually using an item from a quality of life survey that asked "During the past 4 weeks, to what extent were you bothered by loss of taste?" Responses were categorized as normal taste perception if subjects answered "not at all" or altered taste perception if they reported any degree of bother. Time-updated logistic regression models were used to evaluate predictors of altered taste perception. Time-updated linear regression models were used to examine the association between altered taste perception and indices of nutritional status. Multivariable proportional hazards and Poisson models were used to assess association between altered taste perception and mortality and hospitalization, respectively. At baseline, 34.6% reported altered taste perception, which was associated with poorer baseline nutritional status. On time-updated analysis, altered taste perception was associated with a persistently higher proportion of subjects requiring enteral nutritional supplements and lower serum albumin, serum creatinine, normalized protein catabolic rate, protein intake, sodium intake, and mid-arm muscle circumference. Altered taste perception at baseline was independently associated with increased all-cause mortality: adjusted hazard ratio (95% confidence interval) of 1.17 (1.01-1.37), although not with increased rate of hospitalization. Altered taste perception was common among prevalent hemodialysis patients and was independently associated with poorer indices of nutritional status and increased all-cause mortality. Copyright © 2013 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.
Reinoso Carvalho, Felipe; Velasco, Carlos; van Ee, Raymond; Leboeuf, Yves; Spence, Charles
The research presented here focuses on the influence of background music on the beer-tasting experience. An experiment is reported in which different groups of customers tasted a beer under three different conditions (N = 231). The control group was presented with an unlabeled beer, the second group with a labeled beer, and the third group with a labeled beer together with a customized sonic cue (a short clip from an existing song). In general, the beer-tasting experience was rated as more enjoyable with music than when the tasting was conducted in silence. In particular, those who were familiar with the band that had composed the song, liked the beer more after having tasted it while listening to the song, than those who knew the band, but only saw the label while tasting. These results support the idea that customized sound-tasting experiences can complement the process of developing novel beverage (and presumably also food) events. We suggest that involving musicians and researchers alongside brewers in the process of beer development, offers an interesting model for future development. Finally, we discuss the role of attention in sound-tasting experiences, and the importance that a positive hedonic reaction toward a song can have for the ensuing tasting experience.
Kaushik, Deepak; Dureja, Harish
Taste masking is an important factor in the development of oral dosage forms containing bitter active pharmaceutical ingredients. Currently numerous techniques are being applied to overcome this problem. Realizing this, several researchers and pharmaceutical companies are now engaged in developing novel techniques to address the problem of taste masking evident by numerous patents filed in this area in recent times. In this review the most recent patents for taste masking are discussed and how these patents overcome the limitations of conventional approaches of taste masking is also highlighted. Novel techniques based on some recent patents such as nanohybrid, melt extrusion, non-complex cyclodextrin compositions and off taste masking are providing new realms to taste masking of bitter drugs. The present article also provides an overview of various patented platform technologies based on different techniques/mechanisms employed for taste masking. The unique features and principles of taste-masking approaches used in various patented technologies are also discussed. A better understanding of these new patents and patented technologies will help researchers and pharmaceutical industries to select the appropriate platform, or to develop innovative products with improved taste masking properties.
Reinoso Carvalho, Felipe; Velasco, Carlos; van Ee, Raymond; Leboeuf, Yves; Spence, Charles
The research presented here focuses on the influence of background music on the beer-tasting experience. An experiment is reported in which different groups of customers tasted a beer under three different conditions (N = 231). The control group was presented with an unlabeled beer, the second group with a labeled beer, and the third group with a labeled beer together with a customized sonic cue (a short clip from an existing song). In general, the beer-tasting experience was rated as more enjoyable with music than when the tasting was conducted in silence. In particular, those who were familiar with the band that had composed the song, liked the beer more after having tasted it while listening to the song, than those who knew the band, but only saw the label while tasting. These results support the idea that customized sound-tasting experiences can complement the process of developing novel beverage (and presumably also food) events. We suggest that involving musicians and researchers alongside brewers in the process of beer development, offers an interesting model for future development. Finally, we discuss the role of attention in sound-tasting experiences, and the importance that a positive hedonic reaction toward a song can have for the ensuing tasting experience. PMID:27199862
Felipe eReinoso Carvalho
Full Text Available The research presented here focuses on the influence of background music on the beer-tasting experience. An experiment is reported in which different groups of customers tasted a beer under three different conditions (N = 231. The control group was presented with an unlabeled beer, the second group with a labeled beer, and the third group with a labeled beer together with a customized sonic cue (a short clip from an existing song.In general, the beer-tasting experience was rated as more enjoyable with music than when the tasting was conducted in silence. In particular, those who were familiar with the band that had composed the song, liked the beer more after having tasted it while listening to the song, than those who knew the band, but only saw the label while tasting.These results provide support for the idea that customized sound-tasting experiences can complement the process of developing novel beverage (and presumably also food events. Here we also suggest that involving musicians and researchers alongside brewers in the process of beer development, offers an interesting model for future development. Finally, we discuss the role of attention in sound-tasting experiences, and the importance that a positive hedonic reaction towards a song can have for the ensuing tasting experience.
Full Text Available Blood Pressure (BP, comprised of recurrent systoles and diastoles, is controlled by central mechanisms to maintain blood flow. Periodic behavior of BP was modeled to study how peak amplitudes and frequencies of the systoles are modulated by vestibular activation. The model was implemented as a relaxation oscillator, driven by a central signal related to Desired BP. Relaxation oscillations were maintained by a second order system comprising two integrators and a threshold element in the feedback loop. The output signal related to BP was generated as a nonlinear function of the derivative of the first state variable, which is a summation of an input related to desired BP, feedback from the states, and an input from the vestibular system into one of one of the feedback loops. This nonlinear function was structured to best simulate the shapes of systoles and diastoles, the relationship between BP and Heart Rate (HR as well as the amplitude modulations of BP and Pulse Pressure. Increases in threshold in one of the feedback loops produced lower frequencies of HR, but generated large pulse pressures to maintain orthostasis, without generating a VasoVagal Response (VVR. Pulse pressures were considerably smaller in the anesthetized rats than during the simulations, but simulated pulse pressures were lowered by including saturation in the feedback loop. Stochastic changes in Threshold maintained the compensatory Baroreflex Sensitivity. Sudden decreases in Desired BP elicited non-compensatory VVRs with smaller pulse pressures, consistent with experimental data. The model suggests that the Vestibular Sympathetic Reflex modulates BP and HR of an oscillating system by manipulating parameters of the baroreflex feedback and the signals that maintain the oscillations. It also shows that a VVR is generated when the vestibular input triggers a marked reduction in Desired BP.
Tibor Károly Fábián
Full Text Available The gustatory system plays a critical role in determining food preferences and food intake, in addition to nutritive, energy and electrolyte balance. Fine tuning of the gustatory system is also crucial in this respect. The exact mechanisms that fine tune taste sensitivity are as of yet poorly defined, but it is clear that various effects of saliva on taste recognition are also involved. Specifically those metabolic polypeptides present in the saliva that were classically considered to be gut and appetite hormones (i.e., leptin, ghrelin, insulin, neuropeptide Y, peptide YY were considered to play a pivotal role. Besides these, data clearly indicate the major role of several other salivary proteins, such as salivary carbonic anhydrase (gustin, proline-rich proteins, cystatins, alpha-amylases, histatins, salivary albumin and mucins. Other proteins like glucagon-like peptide-1, salivary immunoglobulin-A, zinc-α-2-glycoprotein, salivary lactoperoxidase, salivary prolactin-inducible protein and salivary molecular chaperone HSP70/HSPAs were also expected to play an important role. Furthermore, factors including salivary flow rate, buffer capacity and ionic composition of saliva should also be considered. In this paper, the current state of research related to the above and the overall emerging field of taste-related salivary research alongside basic principles of taste perception is reviewed.
TenBerge, REJ; Krikke, M; Teisman, ACH; Roffel, AF; Zaagsma, J
We studied the function of autoinhibitory muscarinic M(2) receptors on vagal nerve endings in the airways of conscious, unrestrained, ovalbumin-sensitized guinea pigs after the early and late allergic reaction. For this purpose, the effects of the selective muscarinic M(2) receptor antagonist
Wal, R.C. van der; Dillen, L.F. van
In recent years, people have tended to pay less attention to their meals, often consuming them while engaging in other activities. At the same time, foods have become increasingly sweet and salty. We therefore investigated how performing concurrent activities affects taste perception and how this
Full Text Available The current study examined the musical taste of musicology students as compared to a control student group. Participants (n=1003 completed an online survey regarding the frequency with which they listened to 22 musical styles. A factor analysis revealed six underlying dimensions of musical taste. A hierarchical cluster analysis then grouped all participants, regardless of their status, according to their similarity on these dimens