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Human taste cells are a heterogeneous population of specialized epithelial cells that are constantly generated from progenitor taste cells. Type I and type III taste cells express some neural markers, and studies have reported that direct innervation by neurons is not required for taste cell development. To our knowledge, no previous study has demonstrated that taste cells can differentiate into neuron-like cells or any other non-taste cell type. Here, for the first time, we describe a simple in vitro method that uses a serum-free neural induction medium to differentiate cultured physiologically functional primary human taste (HBO) cells into neuron-like cells in 2-3 wk with high efficiency. We verified neural attributes of these HBO-derived neuron-like with immunocytochemistry, single-cell calcium imaging, and DiI staining and examined cell morphology using transmission electron microscopy. Induced neuron-like cells demonstrated neuron-specific proteins, dendritic and axonal morphology, and networking behaviors. This technique will open new avenues for translational medicine, autologous cell therapy, regenerative medicine, therapy for neurodegenerative disorders, and drug screening.

Taste receptors are receptor proteins that detect ligands belonging to the 5 taste modalities: sweet, bitter, sour, salty, and umami. Taste receptors are not restricted to taste cells in taste buds; rather, they are distributed throughout the entire body. For example, solitary chemosensory cells (SCCs) and tuft cells express taste signal proteins and are present in several mucosae. In the airways, SCCs sense bacteria, allergens, viruses, and noxious stimuli and drive evasive behavior, neuroinflammation, and antibacterial responses. In the gut, tuft cells detect helminth infection and bacterial dysbiosis and initiate type II immune responses characterized by tissue remodeling. In the gingiva, SCCs detect oral pathogenic bacteria, evoke innate immune responses and release antimicrobial compounds in the epithelium, and regulate the microbiome composition. This review summarizes the most recent research on extragustatory taste receptors and their function in antibacterial defense. We also discuss how these findings have provided insights into the development of potential therapeutic strategies for mucosal bacterial infection and dental diseases.

Fat taste perception has long been concerned in the regulation of dietary fat intake. Substantial experimental evidence defends fat as a sixth taste modality, but its allied peripheral mechanisms are not yet well established. The present study aimed to analyse the diet-induced changes in fat taste perception and its associated physiological variations in Mus booduga. Four groups of animals were used for the present study and were fed any one of the following diet; normal diet (10% fat), low-fat diet (4% fat), high-fat diet (36% fat), or high-fat diet (HFD) (36% fat) + rapeseed oil (HFRDO) (14%) for 9 weeks. The animals were then subjected to metabolic tolerance, fat preference, and conditioned taste aversion studies. Diet-induced alterations in the expression of genes associated with lipogenesis, inflammation, and fat taste (CD36 and GPR120) were analysed. Capacitative calcium signalling induced by both linoleic acid and grifolic acid in taste bud cells (TBCs) was also analysed. In result, both the HFD and HFDRO groups revealed deterioration in glucose homoeostasis and displayed decreased preference scores for fatty acids, which are associated with lower CD36 expression and increased GPR120 expression in TBCs. Furthermore, change in [Ca

This study aimed to analyze the morphology of the tongue, which varies among fish species and has not been studied in turbot (Scophthalmus maximus), using macro-anatomical, light and scanning electron microscopy (SEM). As research materials, the tongues of eight adult turbot, which were used for consumption, were examined. The roughly triangular-shaped tongue of the turbot consisted of three parts: apex, body, and root. The thickness of the tongue continued to increase from the apex to the root. Although papillae were not observed in the macroscopic examination of the tongue, microscopic examination revealed the presence of cone-like shaped papillae on the submucosa. The tongue was composed of mucosa, submucosa, and hyaline cartilage. By SEM the presence of the taste buds (Types I and III), taste pores and papillae on the dorsal surface were demonstrated. Taste buds are the first descriptions in S. maximus. Therefore our results could add new data to the fish tongue anatomy. HIGHLIGHTS: Morphological and morphometric data of the turbot (Scophthalmus maximus) tongue were obtained in this study and compared with other species. In addition, the dorsal surface of the turbot tongue was described for the first time using SEM.

T1R3 is a class C G protein-coupled receptor family member that forms heterodimeric umami and sweet taste receptors with T1R1 and T1R2, respectively, in the taste cells of taste buds. T1R3 is expressed in 3T3-L1 cells in homomeric form and negatively regulates adipogenesis in a Gαs-dependent but cAMP-independent manner. Although T1R3 expression is markedly upregulated during adipogenesis, its physiological role in mature adipocytes remains obscure. Here, we show that stimulation of T1R3 with sucralose or saccharin induces microtubule disassembly in differentiated 3T3-L1 adipocytes. The effect was reproduced by treatment with cholera toxin or isoproterenol but not with forskolin. Treatment with sucralose or saccharin for 3 h inhibited insulin-stimulated glucose uptake by 32% and 45% in differentiated adipocytes, respectively, similar to the inhibitory effect of nocodazole (by 33%). Isoproterenol treatment inhibited insulin-stimulated glucose transport by 26%, whereas sucralose did not affect the intrinsic activity of the glucose transporter, indicating that it inhibited insulin-induced GLUT4 translocation to the plasma membrane. Immunostaining analysis showed that insulin-stimulated GLUT4 accumulation on the plasma membrane was abrogated in sucralose-treated cells, in association with depolymerization of microtubules. Sucralose-mediated inhibition of GLUT4 translocation was reversed by the overexpression of dominant-negative Gαs (Gαs-G226A) or knockdown of Gαs. Additionally, membrane fractionation analysis showed that sucralose treatment reduced GLUT4 levels in the plasma membrane fraction from insulin-stimulated adipocytes. We have identified a novel non-gustatory role for homomeric T1R3 in adipocytes, and activation of the T1R3 receptor negatively regulates insulin action of glucose transport via Gαs-dependent microtubule disassembly.

Tongue fungiform papillae contain taste buds crucial for taste and hormone-producing taste receptor cells; therefore, they may be considered as endocrine organs and have important age-associated physiological implications. We examine the cross-sectional and longitudinal trajectories of fungiform papillae density in 1084 participants from the Baltimore Longitudinal Study of Aging using linear regression models and mixed effects models. At baseline, the mean age was 67.86 ± 14.20 years, with a mean follow-up time among those with repeat visits of 4.24 ± 1.70 years. Women (53%) were younger (66.85 ± 13.78 vs. 69.04 ± 14.61 years, p < 0.001) and had a higher fungiform papillae density than men (16.14 ± 9.54 vs. 13.77 ± 8.61 papillae/cm2, p < 0.001). Whites (67%) had a lower fungiform papillae density than non-Whites after adjusting for age and sex. Factors cross-sectionally associated with a lower fungiform papillae density included a higher waist-hip ratio (β = −8.525, p = 0.029), current smoking status (β = −5.133, p = 0.014), and alcohol use within the past 12 months (β = −1.571, p = 0.025). Longitudinally, fungiform papillae density decreased linearly with follow-up time (β = −0.646, p < 0.001). The rate of decline was not affected by sex, race, BMI, waist-hip ratio, smoking, or alcohol use. The longitudinal decline of fungiform papillae density over time needs to be explored further in order to identify other possible age-associated physiological determinants.

Depression is associated with taste disorders; however, the mechanisms by which mental stress affects taste perception are not well understood. This study aimed to elucidate the effects of psychosocial stress on peripheral taste-sensing systems using a mouse depression model. Male mice were subjected to subchronic and mild social defeat stress (sCSDS). Results showed that sCSDS significantly increased body weight, food and water intake, and social avoidance behavior and that sCSDS did not change reward-seeking behavior on sucrose preference but tended to decrease pheromonal preference for female urine. Furthermore, sCSDS downregulated the mRNA levels of sweet and umami taste receptor subunits, i.e., sweet taste receptor type 1 members 2 and 3 (T1R2 and T1R3), but not the umami taste receptor subunit, i.e., taste receptor type 1 member 1 (T1R1), in the circumvallate papillae of mice. It is known that sucrose preference is mediated by the gut–brain axis without taste perception; thus, it was considered that sCSDS affected the peripheral taste-sensing systems, rather than the central reward systems, which mediate sucrose preference. This is the first study to report that psychosocial stress affects peripheral sweet and umami taste-sensing systems.

The current work is designed to give the first trial to characterize the ultrastructural lineaments of the oral cavity floor in juvenile and adult white grouper. The present work depends on 10 oral cavities floor from each age. The common features joined the oral cavities floor of the juvenile and adult fish summarized in; oral cavity floor had two teeth bands (lower incisive and lower molar), tongue with its two lateral spinated lines, lower velum, ridges, the lower lip divided into a single anterior part and two lateral part, and the absence of lower canine teeth. The oral surface of semilunar lower velum had round fungiform papillae that carried taste buds type I. The non-protrusible elongated tongue had a clear apex, body, and root with the absence of any taste buds. The dorsal lingual surface of the body had two lateral spinated lines, a single ridge and microtubercles. The smooth dorsal lingual surface of the root did not carry any ridges. The notched lower velum at the middle of the free border was observed in juveniles and adults. Meanwhile, there are some variations between juvenile and adult as; absence of lower incisive ridge only in juvenile, pointed tongue with sublingual ridge observed in juvenile while round without sublingual ridge in adult fish, moreover the presence of velvar ridges observed only in adult fish. The obtained findings provided essential data to aquaculture of this fish species in Egypt by determining the food particle types that are favorite to this fish. HIGHLIGHTS: The common features joined the oral cavities floor of the juvenile and adult fish summarized in; oral cavity floor had two teeth bands (lower incisive and lower molar), tongue with its two lateral spinated lines, lower velum, ridges, the lower lip divided into a single anterior part and two lateral part, and the absence of lower canine teeth. The oral surface of semilunar lower velum had round fungiform papillae that carried taste buds type I. The dorsal lingual surface of the body had two lateral spinated lines, a single ridge and microtubercles. The smooth dorsal lingual surface of the root did not carry any ridges. Meanwhile, there are some variations between juvenile and adult as; absence of lower incisive ridge only in juvenile, pointed tongue with sublingual ridge observed in juvenile while round without sublingual ridge in adult fish, moreover the presence of velvar ridges observed only in adult fish.

Taste and smell play a key role in our ability to perceive foods. Overconsumption of highly palatable energy-dense foods can lead to increased caloric intake and obesity. Thus there is growing interest in the study of the biological mediators of fat taste and associated olfaction as potential targets for pharmacologic and nutritional interventions in the context of obesity and health. The number of studies examining mechanisms underlying fat taste and smell has grown rapidly in the last 5 years. Therefore, the purpose of this systematic review is to summarize emerging evidence examining the biological mechanisms of fat taste and smell. A literature search was conducted of studies published in English between 2014 and 2021 in adult humans and animal models. Database searches were conducted using PubMed, EMBASE, Scopus, and Web of Science for key terms including fat/lipid, taste, and olfaction. Initially, 4,062 articles were identified through database searches, and a total of 84 relevant articles met inclusion and exclusion criteria and are included in this review. Existing literature suggests that there are several proteins integral to fat chemosensation, including cluster of differentiation 36 (CD36) and G protein-coupled receptor 120 (GPR120). This systematic review will discuss these proteins and the signal transduction pathways involved in fat detection. We also review neural circuits, key brain regions, ingestive cues, postingestive signals, and genetic polymorphism that play a role in fat perception and consumption. Finally, we discuss the role of fat taste and smell in the context of eating behavior and obesity.

Zinc is an essential trace element, and its deficiency causes taste dysfunction. Zinc accumulates in zinc transporter (ZnT)3-expressing presynaptic vesicles in hippocampal neurons and acts as a neurotransmitter in the central nervous system. However, the distribution of zinc and its role as a signal transmitter in taste buds remain unknown. Therefore, we examined the distribution of zinc and expression profiles of ZnT3 in taste cells and evaluated zinc release from isolated taste cells upon taste stimuli. Taste cells with a spindle or pyriform morphology were revealed by staining with the fluorescent zinc dye ZnAF-2DA and autometallography in the taste buds of rat circumvallate papillae. Znt3 mRNA levels were detected in isolated taste buds. ZnT3-immunoreactivity was found in phospholipase-β2-immunopositive type II taste cells and aromatic amino acid decarboxylase-immunopositive type III cells but not in nucleoside triphosphate diphosphohydrolase 2-immunopositive type I cells. Moreover, we examined zinc release from taste cells using human transient receptor potential A1-overexpressing HEK293 as zinc-sensor cells. These cells exhibited a clear response to isolated taste cells exposed to taste stimuli. However, pretreatment with magnesium-ethylenediaminetetraacetic acid, an extracellular zinc chelator - but not with zinc-ethylenediaminetetraacetic acid, used as a negative control - significantly decreased the response ratio of zinc-sensor cells. These findings suggest that taste cells release zinc to the intercellular area in response to taste stimuli and that zinc may affect signaling within taste buds.

Amino acids contribute to the taste of foods. Previous studies on the taste of amino acids focused mainly on α-amino acids, and therefore, the taste characteristics of amino acid derivatives remain unclear. In the present study, we targeted 6 different amino acid derivatives, β-alanine, citrulline, creatine, γ-aminobutyric acid, taurine, and ornithine, and evaluated their taste characteristics in a human sensory study. All tested amino acid derivatives showed multiple taste qualities; no derivatives had only a single taste quality. However, their taste intensities were relatively weak even at high concentrations. Given that the interactions between amino acid derivatives and nucleotide result in taste enhancements, we investigated the effect of inosine 5'-monophosphate (IMP) on the taste characteristics and found that the taste intensity of ornithine increased in the presence of IMP. This finding will be useful for understanding the role of amino acid derivatives as taste substances in daily foods.

Individual differences in sweet taste sensitivity can affect dietary preferences as well as nutritional status. Despite the lack of consensus, it is believed that sweet taste is impacted by genetic and environmental variables. Here we determined the effect of well-established factors influencing the general taste variability, such as gender and fungiform papillae density, specific genetic variants (SNPs of

The gustatory system detects and informs us about the nature of various chemicals we put in our mouth. Some of these have nutritive value (sugars, amino acids, salts, and fats) and are appetitive and avidly ingested, whereas others (atropine, quinine, nicotine) are aversive and rapidly rejected. However, the gustatory system is mainly responsible for evoking the perception of a limited number of qualities that humans taste as sweet, umami, bitter, sour, salty, and perhaps fat [free fatty acids (FFA)] and starch (malto-oligosaccharides). The complex flavors and mouthfeel that we experience while eating food result from the integration of taste, odor, texture, pungency, and temperature. The latter three arise primarily from the somatosensory (trigeminal) system. The sensory organs used for detecting and transducing many chemicals are found in taste buds (TBs) located throughout the tongue, soft palate esophagus, and epiglottis. In parallel with the taste system, the trigeminal nerve innervates the peri-gemmal epithelium to transmit temperature, mechanical stimuli, and painful or cooling sensations such as those produced by changes in temperature as well as from chemicals like capsaicin and menthol, respectively. This article gives an overview of the current knowledge about these TB cells' anatomy and physiology and their trigeminal induced sensations. We then discuss how taste is represented across gustatory cortices using an intermingled and spatially distributed population code. Finally, we review postingestion processing (interoception) and central integration of the tongue-gut-brain interaction, ultimately determining our sensations as well as preferences toward the wholesomeness of nutritious foods. © 2021 American Physiological Society. Compr Physiol 11:1-35, 2021.

Heterogeneous tissue models require the assembly and co-culture of multiple types of cells. Our recent work demonstrated taste signal transmission from gustatory cells to neurons by grafting single-stranded DNA into the cell membrane to construct multicellular assemblies. However, the weak DNA linkage and low grafting density allowed the formation of large gustatory cell self-aggregates that cannot communicate with neurons efficiently. This article presents the construction of artificial taste buds exhibiting active intercellular taste signal transmission through the hybridization of gustatory-neuronal multicellular interfaces using bioorthogonal click chemistry. Hybrid cell clusters were formed by the self-assembly of neonatal gustatory cells displaying tetrazine with a precultured embryonic hippocampal neuronal network displaying trans-cyclooctene. A bitter taste signal transduction was provoked in gustatory cells using denatonium benzoate and transmitted to neurons as monitored by intracellular calcium ion sensing. In the multicellular hybrids, the average number of signal transmissions was five to six peaks per cell, and the signal transmission lasted for ∼5 min with a signal-to-signal gap time of 10-40 s. The frequent and extended intercellular signal transmission suggests that the cell surface modification by the bioorthogonal click chemistry is a promising approach to fabricating functional multicellular hybrid clusters potentially useful for cell-based biosensors, toxicity assays, and tissue regeneration.

Recent literature has demonstrated only adult avian palate, albeit there has been only limited focus on the postnatal development of the avian oropharyngeal cavity roof. Hence, the current investigation was designed to obtain the full ultrastructure postnatal description of the oropharyngeal roof during the five developmental age-stages of Coturnix coturnix by employing assessments using gross morphometric analysis and stero and scanning electron microscopy. The elongated triangular oropharyngeal roof has a spoonful rounded beak tip. The palate region is subdivided into the rostral ridged area and the choanal area. The palate has eight longitudinal palatine ridges (seven nonpapillated and one papillated median) and four transverse papillary rows (one slightly oblique row and three transverse papillary crests). The median palatine ridge continuous caudally and is then divided into three ridges: one median and two paramedian ridges (forming the lateral boundaries of the choanal field). The choanal field had three regions (rostral, middle, and caudal). The finger-like projection papillary region has five papillae. The choanal cleft has two unequal parts (rostral and caudal). The rostral nonpapillated short choanal part is subdivided by transverse papillary row into rostral narrow straight and caudal diamond portions. The caudal wide papillated choanal part is further divided by a second transverse crest into rostral long (encircled by interdigitated papillae) and caudal short wider part (not encircled by interdigitated papillae). The infundibular cleft is not bordered by any papillae, while the pharyngeal region has numerous papillae and openings of the salivary glands. Moreover, the morphometric analysis revealed a higher value with increasing age for all dimensions. Our findings indicated a higher degree of functional adaptation between the five developmental age stages of quail. Our observations suggest that adaptations such as these may increase the efficiency of food prehension with increasing age.

The current investigation gave a full ultrastructural and histological description of the oropharyngeal cavity of the rock-pigeon Columba livia dakhlae. Our study carried on 10 heads of adult rock pigeons by gross, scanning, and light microscopic examination, in addition to the immunohistochemical analysis of the cytokeratin of the dorsal surface mucosa epithelium and the proliferating cell nuclear antigen expression (PCNA) immunoreactivity. The pointed apex of the elongated tongue covered rostrally and laterally with numerous caudally directed scales-like papillae. The dorsal surface of the apex and body was covered with numerous caudally directed scales-like filiform papillae. The U-shaped transverse papillary crest carried caudally directed pointed triangular conical papillae with two giant papillae. The elevated caudal area of the lingual body contains little numbers of the opening of the lingual gland. The laryngeal mound is divided into two symmetrical halves by rostral fissure and caudal laryngeal fissure into the right and left half. There were four palatine ridges: two lateral, middle, and median ridges. The choanal field bounded by the two lateral palatine ridges and containing the median choanae. The rostral part of the palatine cleft bounded laterally by a line of the small caudally directed conical papillae, while the caudal part was free from these papillae. There was a little number of taste buds in the palate. The high magnification of the rostral part of the beak is covered with directed rods-like projections. In conclusion, the obtained results described the adaptations of the tongue and its belonged structures with the feeding demand of the rock-pigeon.

The sense of taste is associated with the evaluation of food and other environmental parameters such as salinity. In aquatic mammals, anatomic and behavioral evidence of the use of taste varies by species and genomic analysis of taste receptors indicates an overall reduction and, in some cases, complete loss of intact bitter and sweet taste receptors. However, the receptors used by taste buds in the oral cavity are found on cells in other areas of the body and play an important role in immune responses. In the respiratory tract, an example of such cells is solitary chemosensory cells (SCCs) which have bitter and sweet taste receptors. The bitter receptors detect chemicals given off by pathogens and initiate an innate immune response. Although many aquatic mammals may not have a role for taste in the assessment of food, they likely would benefit from the added protection that SCCs provide, especially considering respiratory diseases are a problem for many aquatic mammals. While evidence indicates that some species do not possess functional bitter receptors for taste, many do have intact bitter receptor genes and it is important for researchers to be aware of all roles for these receptors in homeostasis. Through a better understanding of the anatomy and physiology of aquatic mammal's respiratory systems, better treatment and management is possible.

Although the technique for taste cell culture has been reported, cultured taste cells have remained poorly validated. This study systematically compared the cultured cells derived from both taste and non-taste tissues. Fourteen cell lines established from rat circumvallate papillae (RCVs* or RCVs), non-taste lingual epithelia (RVEs), and tail skins (RTLs) were analyzed by PCR, immunocytochemistry, proteomics, and calcium imaging. The cell lines were morphologically indistinguishable, and all expressed some taste-related molecules. Of the tested RCVs*, RCVs, RVEs, and RTLs (%), 84.7 ± 7.8, 63.9 ± 22.8, 46.8 ± 0.3, and 40.8 ± 15.1 of them were responsive to at least one tastant or ATP, respectively. However, the calcium signaling pathways in the responding cells differed from the canonical taste transduction pathways in the taste cells

Feeding is one of the most fundamental activities in the survival and reproduction of animals. During feeding, the gustatory system functions as a gatekeeper to evaluate food quality. Accumulated evidence in the field of taste research has shown that 5 basic tastes (sweet, umami, sour, bitter, and salty) are sensed by the corresponding taste receptors expressed in taste receptor cells on the tongue. In contrast, brain mechanisms that transduce or modify taste information have been less studied. In this review, I introduce our recent findings on the sweet taste transduction in the brainstem of mice and explain the hypothalamic neuronal network regulating hunger-induced taste modification. Finally, future perspectives are discussed.

Vismodegib is used in patients suffering from advanced basal cell carcinoma (BCC), but 100% of the patients taking it report dysgeusia and 50% discontinue the treatment. Treatment with neurotrophic factors can stimulate neuronal survival and functional improvement in injured organs. Here, we analysed novel transgenic mouse lines in which brain-derived neurotrophic factor (BDNF) is overexpressed in taste buds, to examine whether higher levels of BDNF would reduce or prevent negative side effects of vismodegib in the taste system. BDNF plays crucial roles for development, target innervation, and survival of gustatory neurons and taste buds. The behavioural test in this study showed that vehicle-treated wild-type mice prefered 10 mM sucrose over water, whereas vismodegib treatment in wild-type mice caused total taste loss. Gustducin-BDNF mice had a significantly increased preference for low concentration of sucrose solution over water compared to wild-type mice, and most importantly the transgenic mice were able to detect low concentrations of sucrose following vismodegib treatment. We evaluated taste cell morphology, identity, innervation and proliferation using immunohistochemistry. All drug-treated mice exhibited deficits, but because of a possible functional upcycled priming of the peripheral gustatory system, GB mice demonstrated better morphological preservation of the peripheral gustatory system. Our study indicates that overexpression of BDNF in taste buds plays a role in preventing degeneration of taste buds. Counteracting the negative side effects of vismodegib treatment might improve compliance and achieve better outcome in patients suffering from advanced BCC.

Taste is one of the essential senses in providing the organism a faithful representation of the external world. Taste perception is responsible for basic food and drink appraisal and bestows the organism with valuable discriminatory power. Umami and sweet are "good" tastes that promote consumption of nutritive food, whereas bitter and sour are "bad" tastes that alert the organism to toxins and low pH, promoting rejection of foods containing harmful substances. Not every animal has the same sense of taste as humans. Variation in the taste receptor genes contributes to inter and intra organism differences of taste (sweet/bitter) sensation and preferences. Therefore a deeper understanding was needed to comprehend taste perception by various vertebrates and accordingly elucidate a possible proximity among them. In this study, a total 20 Type-1 (sweet) and 189 Type-2 (bitter) taste receptor complete-amino acid sequences were taken from the 20 vertebrate organisms (18 mammalian, 1 Aves, and 1 amphibian). Among 10 primates, 8 including humans were very close based on genomics of taste receptors and rodent organisms viz. the rat and mouse were away from them. This investigation throws light on the similitude and dissimilitude of perception of sweet and bitter taste among 20 different organisms, steered by quantitative analysis of their genomic data. Furthermore, it enlightened that ligand binding affinity of sweet/bitter taste molecules in the taste receptors of any proximal pair of organisms would be similar.

Taste cells are a heterogeneous population of sensory receptors that undergo continuous turnover. Different chemo-sensitive cell lines rely on action potentials to release the neurotransmitter onto nerve endings. The electrical excitability is due to the presence of a tetrodotoxin-sensitive, voltage-gated sodium current (I

The present study aims to characterize the ultrastructural roof of the oral cavity roof in juvenile and adult Epinephelus aeneus using SEM. The investigation used 10 roofs of the oral cavity of juvenile and adult stages of age. The results in both age groups showed that the roof had five tooth bands, an upper valve, and a palatine region. The upper lip was divided into the anteriorly median and two lateral parts. The posterior margin of the anterior labial part is not attached to the incisive or canine teeth. The anterior surface of the canine teeth was attached to the transverse part of the upper incisive ridge that was separated from the posterior labial part by a deep groove. The semilunar upper velum showed two surfaces, two borders, and two parts. The median part of the oral surface of the velum carried the extension of the longitudinal part of the upper incisive ridge that had some variation among the two examined age stages. In addition, the median part of the oral surface of the upper velum had two rough areas located laterally on each side of the longitudinal part of the upper incisive ridge. The oral surface had several slightly elevated fungiform papillae with taste buds. The palatine region was divided into the peripheral semilunar part and the wide median part, by palatine teeth and the palatine groove laterally and by vomer teeth anteriorly. The results provided important data for the aquaculture in Egypt in relation to their diet.

Srichairat, N., Taksintum, W.,Chumnanpuen, P. (2022). Histological and histochemical characteristics of the oral, pharyngeal and accessory digestive organs in the water monitor lizard (Varanus salvator) from Thailand. Anatomia Histologia Embryologia, 51, https://doi.org/10.1111/ahe.12846. The water monitor lizard (Varanus salvator) is largely distributed in Southeast Asia, especially Thailand, which the microanatomical structure studies on this particular species have been limited. Therefore, the purpose of this study is to examine and describe the oral, pharyngeal and accessory digestive organs' histological and histochemical characteristics. Histological and histochemical examinations were performed on the two specimens (male and female). The majority of V. salvator oral, pharyngeal and accessory digestive organs are similar to those of other vertebrates, according to the results of the histological investigation. However, several unique characteristics have been observed, such as the dentine lamella (plicidentine fold) at the tooth root structure was discovered to be attached to the jaw bone, the absence of lingual papillae and taste buds on the tongue, and the absence of inner surface folding structures in the gallbladder. Regarding mucin histochemical investigation, acid and neutral mucins were discovered in the pharyngeal glands of V. salvator, whereas only acid mucin was found in the mandibular salivary glands. This study reveals the histological and histochemical characteristics of V. salvator oral, pharyngeal and accessory digestive organs, which could be employed to improve digestive tract function, as well as the necessity of understanding animal digestive processes.

Bitter taste receptors (T2Rs) are G protein-coupled receptors involved in the perception of bitter taste on the tongue. In humans, T2Rs have been found in several sites outside the oral cavity. Although T2R38 has been reported to be expressed on peripheral lymphocytes, it is poorly understood whether T2R38 plays immunological roles in inflammatory skin diseases such as atopic dermatitis (AD). Then, we first confirmed that T2R38 gene expression was higher in lesional skin of AD subjects than healthy controls. Furthermore, skin T2R38 expression levels were correlated with serum thymus and activation-regulated chemokine and IgE levels in AD patients. In lesional skin of AD, section staining revealed that CD3+ T cells in the dermis were T2R38 positive. In addition, flow cytometry analysis showed T2R38 expression in skin T cells. Migration assays using T2R38-transduced Jurkat T cell leukemia cells revealed that T2R38 agonists exerted a dose-dependent migration inhibitory effect. Moreover, skin tissue extracts, as well as supernatants of cultured HaCaT keratinocytes, caused T2R38-dependent migration inhibition, indicating that there should be an endogenous ligand for T2R38 in the skin epidermis. These findings implicate T2R38 as a migratory inhibitory receptor on the skin-infiltrating lymphocytes and as a therapeutic target for allergic/inflammatory skin diseases.

There are variations in the tongue papillae among species, including the size, number and type of papillae. There have been no studies describing the detailed tongue morphology of Javan mongoose (Herpestes javanicus). Therefore, we analysed the tongue and lingual structures of Javan mongoose (H. javanicus), using scanning electron microscopy and light microscopy. The tongue was covered by papillae and rough in appearance. We divided the tongue into three regions: the apex, corpus and radix of the tongue. The medioventral section of the tongue was characterized by the presence of a frenulum. We identified four types of papillae: filiform, fungiform, conical and vallate papillae. There were two subtypes of filiform papillae: leaf-like and conical. Both were seen on the apex, although leaf-like filiform papillae also extended to the corpus. Fungiform papillae had taste buds on their dorsal surfaces and were observed from the apex to the radix. Vallate papillae, three in numbers only occurred on the radix. Periodic acid-Schiff (PAS) staining showed minor lingual glands on the textus muscularis striatus syncytialis of the corpus and lateral radix, which we identified as Weber glands; we also observed von Ebner glands on this layer of the tongue. These anatomical features of the Javan mongoose tongue are broadly similar to those seen in other carnivores, with some specific differences, such as the number of vallate papillae.

Taste buds are complex sensory organs embedded in the epithelium of fungiform papillae (FP) and circumvallate papillae (CV). The sweet, bitter, and umami tastes are sensed by type II taste cells that express taste receptors (Tas1rs and Tas2rs) coupled with the taste G-protein α-gustducin. Recent studies revealed that the taste response profiles of α-gustducin-expressing cells are different between FP and CV, but which genes could generate such distinctive cell characteristics are still largely unknown. We performed a comprehensive transcriptome analysis on α-gustducin-expressing cells in mouse FP and CV by single-cell RNA sequencing combined with fluorescence-activated cell sorting. Transcriptome profiles of the α-gustducin-expressing cells showed various expression patterns of taste receptors. Our clustering analysis defined the specific cell populations derived from FP or CV based on their distinct gene expression. Immunohistochemistry confirmed the specific expression of galectin-3, encoded by Lgals3, which was recognized as a differentially expressed gene in the transcriptome analysis. Our work provides fundamental knowledge toward understanding the genetic heterogeneity of type II cells, potentially revealing differential characterization of FP and CV taste bud cells.

Purpose of Review From single cells to entire organisms, biological entities are in constant communication with their surroundings, deciding what to ‘allow’ in, and what to reject. In very different ways, the immune and taste systems both fulfill this function, with growing evidence suggesting a relationship between the two, through shared signaling pathways, receptors, and feedback loops. The purpose of this review was to explore recent reports on taste and immunity in model animals and in humans to explore our understanding of the interplay between these systems. Recent Findings Acute infections in the upper airway, as with SARS-CoV-2, are associated with a proinflammatory state, and blunted taste perception. Further, recent findings highlight taste receptors working as immune sentinels throughout the body. Work in humans and mice also points to inflammation from obesity impacting taste, altering taste bud abundance and composition. Summary There is accumulating evidence that taste cells, and particularly their receptors, play a role in airway and gut immunity, responsive to invading organisms. Inflammation itself may further act on taste buds and other taste receptor expressing cells throughout the body as a form of homeostatic control.

Background: Although duodenal diverticula are associated with less frequent pathology than the colonic diverticula in the large intestine, their periampullary position may have significant clinical implications. The aim of the study was to identify any possible correlation between the type of localisation of the major duodenal papilla, duodenal diverticula, and some particular clinical issues. Materials and methods: In total, 628 patients (408 females and 220 males; aged 21–91 years), who underwent endoscopic retrograde cholangiopancreatography were included in this study. The patients were divided into two groups: a study group comprising 66 (10.5%) patients with periampullary position of diverticula (group A), and a control group comprising 562 (89.5%) patients without diverticula (group B). Results: A duodenal diverticulum was diagnosed in the periampullary position in 66/628 (10.5%) patients: 41 women (aged 52–91 years) and 25 men (aged 54–83 years). Conclusions: Three types of localisation were observed for the major duodenal papilla with regard to the diverticula, with the most common type being next to each other (type III). In patients with diverticula, similar frequencies of gallstone occurrence are observed in men and women. Patients with papilla in the diverticulum who underwent cholecystectomy are more prone to develop lithiasis.

Sex as a biological variable has been the focus of increasing interest. Relatively few studies have focused, however, on differences in peripheral taste function between males and females. Nonetheless, there are reports of sex-dependent differences in chemosensitivity in the gustatory system. The involvement of endogenous changes in ovarian hormones has been suggested to account for taste discrepancies. Additionally, whether sex differences exist in taste receptor expression, activation, and subsequent signaling pathways that may contribute to different taste responsiveness is not well understood. In this study, we show the presence of both the nuclear and plasma membrane forms of estrogen receptor (ER) mRNA and protein in mouse taste cells. Furthermore, we provide evidence that estrogen increases taste cell activation during the application of fatty acids, the chemical cue for fat taste, in taste receptor cells. We found that genes important for the transduction pathway of fatty acids vary between males and females and that these differences also exist across the various taste papillae. In vivo support for the effect of estrogens in taste cells was provided by comparing the fatty acid responsiveness in male, intact female, and ovariectomized (OVX) female mice with and without hormone replacement. In general, females detected fatty acids at lower concentrations, and the presence of circulating estrogens increased this apparent fat taste sensitivity. Taken together, these data indicate that increased circulating estrogens in the taste system may play a significant role in physiology and chemosensory cellular activation and, in turn, may alter taste-driven behavior. NEW & NOTEWORTHY Using molecular, cellular, and behavioral analyses, this study shows that sex differences occur in fat taste in a mouse model. Female mice are more responsive to fatty acids, leading to an overall decrease in intake and fatty acid preference. These differences are linked to sex hormones, as estradiol enhances taste cell responsiveness to fatty acids during periods of low circulating estrogen following ovariectomy and in males. Estradiol is ineffective in altering fatty acid signaling during a high-estrogen period and in ovariectomized mice on hormone replacement. Thus, taste receptor cells are a direct target for actions of estrogen, and there are multiple receptors with differing patterns of expression in taste cells.

The current study was designed to describe the prenatal developmental stages of the rabbit tongue. Thirty-five embryos of prenatal ages (E16, E19, E23, E25, E28, and Postnatal) were obtained from New Zealand white (NZW) rabbit. The primordia of the tongue were observed on the foundation as early as day 16 prenatal age (E16). The first primordia of lingual papillae were observed that including the primordia of circumvallate papillae at day 19 prenatal (E19). Thickenings of lingual epithelium developed at 19 day prenatal of embryo. At day 23-25 pc, the presence of primordia of foliate papillae was shown in addition to primordia of the fungiform and filiform papillae were found. The development of the final shape of the tongue is a longstanding process that occurs during the prenatal and postnatal life. The first primordia of gustatory papillae appear, and only later primordia of mechanical papillae are formed. In conclusion, the morphogenesis of the tongue and its lingual papillae discussed its herbivorous nature of feeding.

Taste buds are receptor organs for gustation. Two types of taste receptor cells have been identified in taste buds: Type II and Type III cells. Type III cells connect with afferent fibers through conventional chemical synapses. In the present study, we used immunocytochemistry to examine the distribution pattern of Bassoon, a scaffolding protein of the cytomatrix at the active zones of conventional synapses in mouse taste buds. Bassoon was predominantly detected as small puncta in Type III cells. Bassoon-immunoreactive puncta were observed in proximity to or partially overlapping with intragemmal nerve fibers. The distribution pattern of Bassoon in taste buds was similar among circumvallate, fungiform, and foliate taste buds. Immunoelectron microscopy showed Bassoon at the active zones of the conventional synapses of Type III cells in circumvallate taste buds. The present results demonstrate that Bassoon is a marker for synapses between Type III cells and afferent fibers in mouse taste buds.

Mucociliary clearance is a primary defence mechanism of the airways consisting of two components, ciliary beating and transepithelial ion transport (I

Differences in the ability to identify and perceive tastes and smells might influence food consumption and, ultimately, chronic nutrition-related conditions such as overweightness and obesity. This study aimed to investigate the associations between taste sensitivity and odour function, anthropometry, and quantity of fungiform papillae in children at age 11–15. Taste strips (4 base tastes), U-Sniff sticks (12 selected smells), and a filter paper strip impregnated with 6-n-propylthiouracil (PROP) were used. The photographic method was used to estimate the number of fungiform papillae (FP) on the tongue. The results showed that the quantity of FP was not related to anthropometry or gender. The taste test total scores were higher for girls, for whom the median score was 14 (12.0–15.0), than for boys, for whom the median score was 12 (9.0–13.0). Of the children, 13.9% had some difficulty in identifying odours. The Mann–Whitney U test showed that children who were most sensitive to bitter taste had more FP (p = 0.0001). The median score for this group (score = 4) was 34.0 (27.0–37.0). For those who had some problems with correctly assessing all bitter taste strips (score = 0–3), the median score was 24.0 (20.0–31.0). Higher numbers of FP were also observed in tasters, that is, people sensitive to PROP, than in nontasters. Only some measures of the taste function correlated with each other, but not very significantly. We concluded that there are multiple perceptual phases of taste, with no single measure able to entirely represent the sense of taste.

Originally identified on the tongue for their chemosensory role, the receptors for sweet, umami, and bitter taste are expressed in some cancers where they regulate important cellular processes including apoptosis and proliferation. We examined DNA mutations (n = 5103), structural variation (n = 7545), and expression (n = 6224) of genes encoding sweet or umami receptors (TAS1Rs) and bitter receptors (TAS2Rs) in 45 solid tumors subtypes compared to corresponding normal tissue using The Cancer Genome Atlas and the Genotype Tissue Expression Project databases. Expression of TAS1R and TAS2R genes differed between normal and cancer tissue, and nonsilent mutations occurred in many solid tumor taste receptor genes (~ 1–7%). Expression levels of certain TAS1Rs/TAS2Rs were associated with survival differences in 12 solid tumor subtypes. Increased TAS1R1 expression was associated with improved survival in lung adenocarcinoma (mean survival difference + 1185 days, p = 0.0191). Increased TAS2R14 expression was associated with worse survival in adrenocortical carcinoma (−1757 days, p p = 0.0041), but improved survival in non-papillary bladder cancer (+ 343 days, p = 0.0436). Certain taste receptor genes may be associated with important oncologic pathways and could serve as biomarkers for disease outcomes.

The mouse bitter taste receptors (Tas2rs) that respond to resveratrol, a bitter-tasting polyphenolic compound, were identified. Among 35 members of the Tas2r family, Tas2r108, 109, 131, and 137 responded to resveratrol treatment. mRNA expression levels of Tas2r108 and Tas2r137 were higher than those of Tas2r109 and Tas2r131 in mouse circumvallate papillae, indicating that Tas2r108 and Tas2r137 may play important roles in detecting the bitterness of resveratrol in the oral cavity. The mRNA expression levels of Tas2r137 and Tas2r108 were also observed in several tissues, suggesting that Tas2r108 and Tas2r137 may also be involved in the physiological action of resveratrol.

The chapter presents an argument supporting the view that taste, defined as the receptor-mediated signaling of taste cells and consequent sensory events, is proper subject matter for the field of pharmacology. The argument develops through a consideration of how the field of pharmacology itself is to be defined. Though its application toward the discovery and development of therapeutics is of obvious value, pharmacology nevertheless is a basic science committed to examining biological phenomena controlled by the selective interactions between chemicals - regardless of their sources or uses - and receptors. The basic science of pharmacology is founded on the theory of receptor occupancy, detailed here in the context of taste. The discussion then will turn to consideration of the measurement of human taste and how well the results agree with the predictions of receptor theory.

Understanding taste is key for optimizing the palatability of seaweeds and other non-animal-based foods rich in protein. The lingual papillae in the mouth hold taste buds with taste receptors for the five gustatory taste qualities. Each taste bud contains three distinct cell types, of which Type II cells carry various G protein-coupled receptors that can detect sweet, bitter, or umami tastants, while type III cells detect sour, and likely salty stimuli. Upon ligand binding, receptor-linked intracellular heterotrimeric G proteins initiate a cascade of downstream events which activate the afferent nerve fibers for taste perception in the brain. The taste of amino acids depends on the hydrophobicity, size, charge, isoelectric point, chirality of the alpha carbon, and the functional groups on their side chains. The principal umami ingredient monosodium l-glutamate, broadly known as MSG, loses umami taste upon acetylation, esterification, or methylation, but is able to form flat configurations that bind well to the umami taste receptor. Ribonucleotides such as guanosine monophosphate and inosine monophosphate strongly enhance umami taste when l-glutamate is present. Ribonucleotides bind to the outer section of the venus flytrap domain of the receptor dimer and stabilize the closed conformation. Concentrations of glutamate, aspartate, arginate, and other compounds in food products may enhance saltiness and overall flavor. Umami ingredients may help to reduce the consumption of salts and fats in the general population and increase food consumption in the elderly.

The morphology of tongue in straw-coloured fruit bat from tropical forests was evaluated in relation to frugivorous diets and in comparison with other species that consumes other food types. Gross, stereomicroscopy, scanning electron microscope and histological methods were used. The tongue was relatively long with round tip, which closely fitted into oral cavity. Five types of mechanical papillae included crown-like and trifid filiform papillae. Also bulky, cone-shaped papillae and long conical papillae were identified. These mechanical types also showed variations in shape, size and number of processes of papillae. Transitional forms of these mechanical papillae were present. Fungiform papillae with taste pores were interposed amongst filiform types in apex and body; three ovoid-shaped vallate papillae were in triangular arrangement on root and displayed taste pores. Some bulky, cone-shaped papillae surrounded the vallate papillae. Histologically, mechanical filiform types showed highly keratinized stratified squamous epithelium and dense connective tissue core with secondary papillae. Taste buds appeared in fungiform and vallate papillae. Neutral and acidic secretions were identified in lingual glands of root. The presence of prominent filamentous processes of filiform papillae and conical papillae of the tongue in conjunction with gustatory papillae ensures adaptation to copious fruit diets. The gross morphometric and histometric parameters of the tongue did not differ remarkably from previous values obtained for some fruit bats with comparable weight. This investigation showed similarities with fruit bats such as large flying fox and Egyptian fruit bat and reflect common diet and feeding habits but varied from insectivorous and nectivorous bats.

New findings What is the central question of this study? Loss of taste or inability to distinguish between different tastes progresses with age. The purpose was to evaluate the age-dependent changes in taste by studying the electrophysiological properties of taste receptor cells. What is the main finding and its importance? Ageing decreased the voltage-gated Na+ and K+ current densities of type III cells (sour and/or salt receptor cells) but did not affect the current densities in type II cells. At the peripheral levels, the excitability of type III cells was reduced due to ageing, which may affect the signal transduction to taste nerves. Abstract The loss of taste due to normal ageing in mammals is assumed to be caused by the ageing of taste receptor cells. We examined the electrophysiological properties of taste receptor cells in the fungiform taste buds of ∼20-month-old mice in situ and subsequently identified their cell types with immunological markers: the inositol 1,4,5-trisphosphate (IP3 ) receptor (IP3 R3) for type II cells and a SNARE protein, synaptosomal-associated protein 25 (SNAP-25), for type III cells. Other cells are referred to as non-immunoreactive cells (non-IRCs). Cell types of some cells that could not be identified using cell-type markers were identified based on the electrophysiological feature of the respective cell types. All cell types generated action potentials and a variety of voltage-gated currents. The type II cells mainly expressed tetraethylammonium (TEA)-insensitive and slowly activating outwardly rectifying currents and generated tail currents in repolarization. In contrast, the type III cells expressed TEA-sensitive and faster activating K+ currents and did not generate tail currents. These cell type-specific characteristics of voltage-gated currents in ∼20-month-old mice were similar to their respective cell types in ∼2-month-old mice. Also, we showed an age-dependent decrease in Na+ and K+ current densities in type III cells and an age-dependent increase in outwardly rectifying current density in non-IRCs. Ageing did not affect the voltage-gated current densities in type II cells. The decreased Na+ and K+ current densities, i.e. the decreased excitability of type III cells, due to ageing may affect the signal transduction to taste nerves.

The morphology of different lingual papillae of the Egyptian goats was studied by gross observation, scanning electron microscopy, and light microscopy. According to function, two types of papillae were present; mechanical (filiform, conical and lenticular papillae) and gustatory papillae (fungiform and vallate papillae). Two types of filiform papillae were detected with different shape and position. Moreover, two types of conical and lenticular papillae could be recognized on the lingual torus. Abundant fungiform papillae were found on the dorsal and ventral surfaces of the tip of the tongue. The vallate papillae had also different shapes. Taste buds were demonstrated within the epithelium of the dorsal surfaces of the fungiform papillae and the lateral surfaces of the vallate papillae. In addition, a longitudinal row of large papillae was located on the lateral aspect of the tongue in relation to the filiform papillae. These papillae were suggested to be called elongated conical papillae and may be considered as ones of the lingual papillae. In conclusion, the current study provides a detailed description of the different lingual papillae of the Egyptian goat's tongue. Presence of different types and shapes of mechanical and gustatory lingual papillae in goats' tongue suggests a high degree of functional adaptation to their diet.

Mammalian taste bud cells have a limited lifespan and differentiate into type I, II, and III cells from basal cells (type IV cells) (postmitotic precursor cells). However, little is known regarding the cell lineage within taste buds. In this study, we investigated the cell fate of Mash1-positive precursor cells utilizing the Cre-loxP system to explore the differentiation of taste bud cells. We found that Mash1-expressing cells in Ascl1CreERT2::CAG-floxed tdTomato mice differentiated into taste bud cells that expressed aromatic L-amino acid decarboxylase (AADC) and carbonic anhydrase IV (CA4) (type III cell markers), but did not differentiate into most of gustducin (type II cell marker)-positive cells. Additionally, we found that Mash1-expressing cells could differentiate into phospholipase C β2 (PLCβ2)-positive cells, which have a shorter lifespan compared with AADC- and CA4-positive cells. These results suggest that Mash1-positive precursor cells could differentiate into type III cells, but not into most of type II cells, in the taste buds.

Taste preferences influence not only the formation of human health, but also many areas of his life. That is why the problem of understanding the nature and regularities of taste formation has been a concern for scientists since ancient times and remains relevant nowadays. The article presents generalized data on the history of studying taste from the times of Ancient Greece to our time. Notions about the system of taste sensations in works of Aristotle, Galen, Avicenna, Vesaliy, other medieval scientists and researchers of New time are described. The authors also present an overview of current studies on the evolutionary appropriateness of taste sensations using the expression of sweet taste receptors in animals with different diets. It has been shown that obligate carnivorous animals have lost the function of sweet taste receptors, and in hummingbirds eating sweet floral nectar, on the contrary, another sweet taste receptor has acquired the function of a sweet taste receptor to detect sugars. The authors pay special attention to the available ways of forming correct taste preferences and overcoming eating disorders in infants, which is important from the point of view of the child’s future health. In particular, strategies for repeated taste effects of new foods as well as multisensory interactions with food, including sound, visual, olfactory, tactile and tasting effects are presented. It is particularly important to develop correct taste habits in children with eating disorders such as neophobia and food selectivity. Understanding the multifactorial nature of taste preferences and their impact on human health allows finding new strategies to «teach» taste from early childhood.

INTRODUCTION: South African adolescents consume relatively low fruit and vegetables in spite of the development of food-based dietary guidelines for South Africa. AIMS AND OBJECTIVES:The aims and objectives of the present study were to investigate parents' perception of their role in the prevention of the health compromising behaviour of inadequate consumption of fruit and vegetables among adolescents in South Africa. DESIGN: The study design was qualitative and exploratory and the research strategy used was inductive, deductive and abductive. METHODS: Using a guiding question schedule data were collected from Ave focus group interviews. A non-probability purposive theoretical sampling method was utilized and the sample size of 37 determined by theoretical saturation. Data analysis was performed using the grounded theory approach. RESULTS: The findings of the study suggest that children should be introduced to fruit and vegetables as early as possible. CONCLUSION: The study recommends that infants should be exposed to the taste of locally available fruit and vegetables followed by the gradual introduction of fruit and vegetables into their diet together with a variety of other nutrient-dense foods when solid foods are being introduced.

Bitter taste receptors (hTAS2R) are expressed ectopically in various tissues, raising the possibility of a pharmacological exploitation. This seems of particular relevance in airways, since hTAS2Rs are involved in the protection of the aerial tissues from infections and in bronchodilation. The bis-guaianolide absinthin (1), one of the most bitter compounds known, targets the hTAS2R46 bitter receptor. Absinthin (1), an unstable compound, readily turns into anabsinthin (2) with substantial retention of the bitter properties, and this compound was used as a starting material to explore the chemical space around the bis-guaianolide bitter pharmacophore. Capitalizing on the chemoselective opening of the allylic lactone ring, the esters 3 and 4, and the nor-azide 6 were prepared and assayed on human bronchoepithelial (BEAS-2B) cells expressing hTAS2R46. Anti-inflammatory activity was evaluated by measuring the expression of MUC5AC, iNOS, and cytokines, as well as the production of superoxide anion, qualifying the methyl ester 3 as the best candidate for additional studies.

The aim of this study was to examine taste function in patients who reported improvement in their pain level after treatment to determine if pain reduction is associated with change in taste function in patients with burning mouth syndrome (BMS).This retrospective study of patients with BMS was conducted at a private oral medicine clinic.Thirty-nine patients with BMS (31 females and 8 males; mean age 56.1 ± 9.4 years) reported improvement in their pain in 1 to 22 months after the initial visit (mean 5.13 ± 4.18). The most commonly used medication was clonazepam 0.25 to 0.5 mg/day. Twenty-eight patients were treated with a combination of medications. "Salt" and "bitter" responses at the fungiform papillae were increased after treatment (P = .026 and P = .044, respectively). "Salt" responses at the circumvallate papillae also increased (P.001). Pain reduction was significant after treatment in the morning (P = .002) and in the evening (P.001).Treatment of BMS can significantly decrease pain symptoms, resulting in improvement in taste function. Pain reduction often requires a combination of medications.

This study aimed to investigate the postnatal morphological features of rabbit's lingual gustatory papillae using histological, histochemical, morphometrical and scanning electron microscopical studies. A total of 48 New Zealand rabbits (1, 7, 15, 23, 30, 60 days postnatal) were used as the material. Tongue consisted of an apex, body and root with three types of gustatory papillae fungiform, vallate and foliate. Rounded to oval fungiform papillae were distributed on lingual apex among filiform papillae. Two foliate papillae on lateroposterior side have parallel folia increased progressively in number (14-20) with age advancement. Two oval vallate papillae on lingual root surrounded by annular grooves. Histologically, the gustatory papillary epithelium was thin at birth then increased in stratification and cornification from third to fourth week. Vallate and foliate grooves were shallow in newborns then grew deeply by desquamation of their lining epithelium which completely opened and connected with lingual excretory ducts at 23 days. Developing serous von Ebner's glands appeared at 23 days and became lobulated form 1-2 months. They gave a negative reaction with Periodic Acid Schiff-Alcian blue stain, while mucous Weber's glands showed Alcian blue positive reaction. Taste buds were firstly seen at 15 days old, increased in number and size and became mature with taste pores from third to fourth week. They distributed dorsally on fungiform and on lateral sides of vallate and foliate. This structural adaptation and maturity of gustatory papillae to meet the functional demands of food ingestion during the transition from suckling to dry matter feeding.

The current study was done to provide comprehensive information on the anatomical features of the lips and cheeks of the goat by gross examination and morphometric analysis in addition to scanning electron microscope (SEM). Samples from 12 normal healthy adult goat's heads of both sexes were collected directly after slaughtering. The lips and cheeks were dissected, and specimens were collected for both light and SEM. The lips of goat were soft and mobile. The free border of both lips was characterized rostrally by the presence of labial projections. The number, size, and arrangement of labial projections differed in the upper and lower lips. On the other hand, the buccal papillae were arranged into 6-8 longitudinal rows parallel to the cheek teeth. The length of these papillae decreased caudally while they were absent on the most caudal part of the cheek. Presence of several types and shapes of labial projections and papillae, and buccal papillae suggest a high degree of mechanical adaptation of the lips and cheeks of the goat. This study provides baseline data for clinical studies. This study is the first report to shed light on the morphology of the lips and cheeks of the goat by gross and scanning electron microscopy.

Inborn genetic differences in chemosensory receptors can lead to differences in perception and preference for foods and beverages. These differences can drive market segmentation for food products as well as contribute to nutritional status. This knowledge may be essential in the development of foods and beverages because the sensory profiles may not be experienced in the same way across individuals. Rather, distinct consumer groups may exist with different underlying genetic variations. Identifying genetic factors associated with individual variability can help better meet consumer needs through an enhanced understanding of perception and preferences. This review provides an overview of taste and chemesthetic sensations and their receptors, highlighting recent advances linking genetic variations in chemosensory genes to perception, food preference and intake, and health. With growing interest in personalized foods, this information is useful for both food product developers and nutrition health professionals alike.

A mouse single taste bud contains 10–100 taste bud cells (TBCs) in which the elongated TBCs are classified into 3 cell types (types I–III) equipped with different taste receptors. Accordingly, differences in the cell numbers and ratios of respective cell types per taste bud may affect taste-nerve responsiveness. Here, we examined the numbers of each immunoreactive cell for the type II (sweet, bitter, or umami receptor cells) and type III (sour and/or salt receptor cells) markers per taste bud in the circumvallate and foliate papillae and compared these numerical features of TBCs per taste bud to those in fungiform papilla and soft palate, which we previously reported. In circumvallate and foliate taste buds, the numbers of TBCs and immunoreactive cells per taste bud increased as a linear function of the maximal cross-sectional taste bud area. Type II cells made up approximately 25% of TBCs irrespective of the regions from which the TBCs arose. In contrast, type III cells in circumvallate and foliate taste buds made up approximately 11% of TBCs, which represented almost 2 times higher than what was observed in the fungiform and soft palate taste buds. The densities (number of immunoreactive cells per taste bud divided by the maximal cross-sectional area of the taste bud) of types II and III cells per taste bud are significantly higher in the circumvallate papillae than in the other regions. The effects of these region-dependent differences on the taste response of the taste bud are discussed.