Search Results (88)

Background: Taste disorders in patients with type 2 diabetes mellitus (T2DM) have a negative impact on their quality of life and glycemic control, and treatment options are limited. Buzhong yiqi formula (BZYQF) improves T2DM symptoms but its effects on T2DM-induced taste disorders have not been sufficiently studied. Methods: Molecular docking was utilized to evaluate binding activity between the compounds in BZYQF and the sweet taste receptors (STRs). T2DM was induced in rats through the administration of high-fat diet and streptozotocin, and the rats were then treated with BZYQF for 8 weeks. Daily indicators and serum biochemical factors were monitored. Taste preferences for sweet, bitter, salty, and sour solutions were assessed using a two-bottle test. The morphology of lingual papillae and the numbers of taste buds were examined using HE staining. A high-glucose (HG) model of taste bud organoids was established to measure sucrose-evoked ATP release. The expression of signaling molecules in the sweet taste receptors (STRs) pathway was determined via RT-qPCR, Western blot, and immunofluorescence in lingual papillae and organoids. Results: A total of 508 compounds in BZYQF indicated good binding activity to T1R2, T1R3 or heterodimers of T1R2/T1R3, and 60 compounds had good binding activity to all three forms of STRs. BZYQF alleviated T2DM symptoms and improved taste perception for maltose (10 mM, 50 mM), quinine (0.03 mM, 0.1 mM), and citric acid (1 mM) solutions. BZYQF improved the morphological structure of lingual papillae and increased taste bud numbers in T2DM rats. BZYQF enhanced ATP release responses to sucrose solution in the taste bud organoids of the HG model. Gene expression determination showed that BZYQF upregulated the expression of signaling molecules in the STRs pathway (T1R2, T1R3, IP3R, α-gustducin, TRPM5) in the lingual papillae of the T2DM rats and in the taste bud organoids of the HG model. Conclusions: BZYQF alleviates T2DM-induced taste disorders by increasing the numbers of taste buds and upregulating STR signaling molecules, in which various compounds, especially flavonoids, exhibit a synergistic effect. Full article

Umami taste compounds are perceived in broilers through taste buds that detect peptides and amino acids, which can positively or negatively affect their feeding behavior. In this study, we evaluated the intake behavior for four essential amino acids (Lysine, Methionine, Threonine, and Tryptophan) in chickens. Sixty-four one-day-old male birds (Ross 308) were used. For 16 days during the early stage of the birds, two-choice preference tests were performed, in which 16 combinations composed of four amino acids in four concentrations (0.1 to 1.5%) diluted in water were evaluated, which were supplied in contrast to the delivery of water (a neutral compound) to a pair of birds in a pen for 4 h of administration after a prior 1 h fast. Amino acid solutions such as Threonine and Tryptophan tended to show less preference at the highest exposed concentrations (1.5%) concerning drinking water, which was confirmed in the case of Threonine when performing a sensory-motivated intake analysis (SMI). The opposite occurred with Lysine (1.5%), which numerically showed a higher preference ratified by SMI and acceptability analysis concerning water and other concentrations of the same amino acid, respectively. When palatability was measured with pecking cluster size, no significant differences across amino acid concentrations were observed, which is probably attributed to short recording periods and differences in solution intake behavior between chickens and previous experimental models such as rats. The results reinforce the notion that it is necessary to standardize feeding behavior tests in birds according to their feeding patterns and nutritional needs. Full article

Capparis spinosa is an edible plant with a long history in the Mediterranean region since antiquity. Its flower buds and leaves are mostly consumed salted or fermented (in vinegar) and are rarely eaten raw or dried. For the first time, caper samples subjected to different preservation processes (dried, salted, and desalted) were studied, foraged from the most producing Cycladic islands in Greece (Sifnos, Serifos, and Tinos). The quantitative determination of the flavonoids rutin and quercetin was carried out using high performance thin-layer chromatography (HPTLC), revealing the abundance of rutin in the buds and leaves (9.26–76.85 mg/g dry extract). Only one sample of desalted buds from Serifos showed a sufficient amount of quercetin (2.88 mg/g dry extract). The determination of total phenolic content (TPC) showed a decrease during brine (salted) preservation (11.7–37.7 mg GAE/g extract) compared to air-dried samples (50.9–62.4 mg GAE/g extract). The DPPH evaluation (8.0–35.2% inhibition at 200 μg/mL) was in agreement with the TPC results. All extracts showed stronger activity against Gram positive bacteria and the human pathogenic fungi C. glabrata. The samples from Sifnos exerted better bioactivities, with air-drying being the most effective preservation process in terms of antioxidant properties and phenolic content, although it resulted in a more bitter taste. Due to its high economic value, the caper holds great potential for further exploitation through better established and optimized processes in the food industry. Full article

Background: Obesity is associated with the altered gustatory perception of dietary fatty acids. Celastrol, a triterpene, has been demonstrated to exert anti-obesity effects in rodents. We assessed the role of Celastrol in the modulation of the oro-sensory perception of lipids in control and high-fat diet (HFD)-induced obese mice. Methods: Male mice of the C57B/6J strain were fed a HFD for 11 weeks and then were administered or not with Celastrol further for 4 weeks. The body weight was recorded weekly. Before the sacrifice, the animals were subjected to oro-sensory detection of a dietary long-chain fatty acid in a two-bottle choice paradigm. After the sacrifice, the fungiform taste buds were isolated and analyzed for mRNA expression, encoding fat sensors (CD36 and GPR120) and pro-inflammatory cytokines (IL-1β, IL-6 and TNF-α). Circulating concentrations of IL-6 and TNF-α were also determined, and liver was used to analyze the mRNA expression of lipogenic genes. Results: Celastrol administration in obese mice decreased body weight and also re-established the loss of oro-sensory perception for a dietary fatty acid, and this phenomenon was, in part, due to the upregulation of mRNA, encoding fat taste receptors (CD36 and GPR120) in tongue taste bud cells. Furthermore, Celastrol decreased inflammation both in taste buds and blood circulation. Conclusions: Our findings suggest that Celastrol decreases body weight gain, ameliorates the gustatory perception of lipids, and downregulates inflammation in obese mice. Full article

Background/Objectives: Taste guides the consumption of food and alcohol for both humans and rodents. Given that chronic dietary exposure to bitter and sweet foods are purported to alter the perception of bitter and sweet tastes respectively, we hypothesized that dietary habits may shape how the taste properties of ethanol are perceived and thus how it is consumed. Methods: Using C57BL/6 mice as a model, we contrasted taste behavior, morphology, and expression after a 4-week diet featuring consistent bitter, sweet, or neutral (water) stimuli. Results: Our results demonstrated that a 4-week bitter diet containing a quinine solution increased preference for ethanol, while a 4-week sweet diet consisting of a sucralose solution did not alter ethanol preference nor intake. The quinine diet also reduced the number of sweet- or umami-sensing T1R3-positive cells in the circumvallate papillae taste buds of the mice. Conclusions: Based on the behavioral changes observed with the bitter diet, it is possible that either bitter or sweet taste, or both together, drive the increase in ethanol preference. The implications of these findings for alcohol consumption are that dietary habits that do not necessarily concern alcohol may be capable of altering alcohol preference via taste habituation. Habitual intake of bitter and/or sweet foods can shift the perception of taste over time. Changes to how the taste components of alcohol are perceived may also alter how acceptable the taste of alcohol is when experienced as a whole, thereby having the unintended consequence of shifting alcohol consumption levels. Our study demonstrates another side to bitter habituation, which, thus far, has been studied in the more positive context of developing a set of dietary tactics for promoting bitter vegetable intake. Full article

Flavonoids are secondary metabolites that are beneficial to life activities and are mainly concentrated in buds and leaves in the form of glycosides. Flavonoid glycosides have important effects on the properties and quality of tea plants. Research has shown that the abundance of flavonoid glycosides varies greatly among different cultivars, but research on the regulatory mechanisms that cause their differential accumulation among tea plant cultivars with different leaf colors is lacking. In this study, an integrated analysis of metabolomics and transcriptomics was conducted to determine the regulatory networks regulating astringency and color-related flavonoids in tea plant cultivars with diverse leaf colors. A total of five anthocyanidins, four catechins, and nine flavonol glycosides were found to partially contribute to the differences in taste and leaf color among tea plant cultivars with diverse leaf colors. Furthermore, 15 MYB genes and 5 Dof genes were identified as potential regulators controlling the expression of eight key structural genes, resulting in differences in the accumulation of specific compounds, including epicatechin (EC), catechin (C), cyanidin, cyanidin 3-O-glucoside, pelargonidin 3-O-glucoside, and quercetin 3-O-glucoside, in tea plant cultivars with diverse leaf colors. These findings provide insights into the development and utilization of resources from tea plants with diverse leaf colors. Full article

Vertebrates’ tongues reflect part of their adaptations to diverse feeding strategies, the types of food items they eat, and the environments where they live. Our contribution was to analyze the macro- and microscopic morphology of the tongues of two porpoise species (Phocoena dioptrica and Phocoena spinipinnis; juveniles and adults), whose biology is little known. Macroscopic and microscopic studies (conventional histology, scanning electron microscopy, immunohistochemistry, and morphometry) were performed. Differences between juvenile and adult individuals of the same species, as well as between juveniles and adults of both species, were found, probably related to their feeding and/or geographical distribution. In addition, novel aspects related to ontogenetic morphological differences, thermoregulation, and immune system components were described. We found a lingual countercurrent vascular system (periarterial venous retia), only mentioned for mysticetes and Physeter macrocephalus (never for smaller odontocetes). In addition, we identified mechanoreceptors (lamellar corpuscles). Both species showed marginal papillae, but only in P. spinipinnis were small (probably vestigial) taste buds observed. Finally, lingual lymphoid aggregates were found. Full article

Bitter taste perception is crucial for animal survival. By detecting potentially harmful substances, such as plant secondary metabolites, as bitter, animals can avoid ingesting toxic compounds. In vertebrates, this function is mediated by taste receptors type 2 (T2Rs), a family of G protein-coupled receptors (GPCRs) expressed on taste buds. Given their vital roles, T2Rs have undergone significant selective pressures throughout vertebrate evolution, leading to frequent gene duplications and deletions, functional changes, and intrapopulation differentiation across various lineages. Recent advancements in genomic and functional research have uncovered the repertoires and functions of bitter taste receptors in a wide range of vertebrate species, shedding light on their evolution in relation to dietary habits and other ecological factors. This review summarizes recent research on bitter taste receptors and explores the mechanisms driving the diversity of these receptors from the perspective of vertebrate ecology and evolution. Full article

Background/Objectives: Taste dysfunction is a frequent symptom of acute coronavirus disease (COVID)-19 caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). While the majority of those affected reported recovery over time, emerging data suggest that 20–25% of individuals experience persistent taste dysfunction, constituting a common symptom of long COVID. Gustation is mediated by continuously renewing taste bud cells. A balance between the counteracting processes of cell generation and cell death maintains the homeostatic turnover. Sonic hedgehog (SHH) is a morphogenic protein that promotes taste cell proliferation and differentiation. Enzymatic proteins such as gustin modulate the environment around the taste receptors and influence taste perception. Hence, we hypothesized that increased taste cell turnover and reduced taste-related salivary proteins contribute to the taste dysfunction in long COVID. Methods: Unstimulated whole saliva (UWS) was collected from individuals with long COVID experiencing taste dysfunction after obtaining informed consent. The normal control included archived saliva samples catalogued prior to 2019. Taste perception was objectively determined by the waterless empirical taste test. The SHH, gustin, and inflammatory cytokines in UWS were determined with ELISA. The expressions of epithelial and taste-cell-specific markers in cellular saliva were assessed by immunoflurorescence. Results: Impaired bitter taste was the most common dysfunction in the long-COVID cohort. Salivary gustin was significantly lower in those with long COVID and correlated with lower bitter taste score. Cellular saliva showed keratin-10- and small-proline-rich protein-positive epithelial cells as well as SHH-, occluding- and KCNQ1-positive taste cells. Conclusions: Salivary gustin could be a marker for impaired bitter taste in long COVID. Full article

Grass carp (Ctenopharyngodon idella) is a Cyprinid fish of aquacultural and research importance. The buccal cavity represents the gateway of the digestive tract. The present study investigated the adaptational changes involving various components of the buccal cavity of fingerling (three months posthatching, mph), yearling (12 mph), and adult (48 mph) C. idella using scanning electron microscopy, histology, and morphometry. The upper and lower lips appeared uninterrupted at the three studied stages and were limited caudally by the upper and lower jaws. The jaw epithelium was the thickest part of the buccal epithelium; ultrastructurally, it appeared smooth with ridge-like borders in fingerlings that transformed into microgrooves in yearlings. In adult C. idella, the jaw mucosa was organized into dome-shaped masses separated from each other by tight furrows. Each mass was formed from several keratinocytes with corrugated surfaces that featured numerous microdepressions. Except for the jaws, taste buds, mainly of type I, and acidic and neutral goblet cells were observed throughout the mucosa of the buccal cavity, and their densities were highest along the mucosal folds of the palate and oral floor, suggesting a principal role for these parts in both gustation and food lubrication. This study is the first to report age-associated spatiotemporal changes in the buccal cavity of grass carp and will serve as a fundamental reference during the interpretation of various types of oral pathologies in teleost. Full article

Background/Objectives: Adiponectin, the most abundant peptide hormone secreted by adipocytes, is a well-known homeostatic factor regulating lipid metabolism and insulin sensitivity. It has been shown that the adiponectin receptor agonist AdipoRon selectively enhances cellular responses to fatty acids in human taste cells, and adiponectin selectively increases taste behavioral responses to intralipid in mice. However, the molecular mechanism underlying the physiological effects of adiponectin on fat taste in mice remains unclear. Conclusions: Here we define AdipoR1 as the mediator responsible for the enhancement role of adiponectin/AdipoRon on fatty acid-induced responses in mouse taste bud cells. Methods and Results: Calcium imaging data demonstrate that AdipoRon enhances linoleic acid-induced calcium responses in a dose-dependent fashion in mouse taste cells isolated from circumvallate and fungiform papillae. Similar to human taste cells, the enhancement role of AdipoRon on fatty acid-induced responses was impaired by co-administration of an AMPK inhibitor (Compound C) or a CD36 inhibitor (SSO). Utilizing Adipor1-deficient animals, we determined that the enhancement role of AdipoRon/adiponectin is dependent on AdipoR1, since AdipoRon/adiponectin failed to increase fatty acid-induced calcium responses in taste bud cells isolated from these mice. Brief-access taste tests were performed to determine whether AdipoRon’s enhancement role was correlated with any differences in taste behavioral responses to fat. Although AdipoRon enhances the cellular responses of taste bud cells to fatty acids, it does not appear to alter fat taste behavior in mice. However, fat-naïve Adipor1^−/− animals were indifferent to increasing concentrations of intralipid, suggesting that adiponectin signaling may have profound effects on the ability of mice to detect fatty acids in the absence of previous exposure to fatty acids and fat-containing diets. Full article

Sprinkle formulations represent an interesting genre of medicinal products. A frequent problem, however, is the need to mask the unpleasant taste of these drug substances. In the present work, we propose the use of a novel sensor array based on solid-state ion-selective electrodes to evaluate the taste-masking efficiency of rosuvastatin (ROS) sprinkle formulations. Eight Multiple Unit Pellet Systems (MUPSs) were analyzed at two different doses (API_50) and (API_10), as well as pure Active Pharmaceutical Ingredient (API) as a bitter standard. Calcium phosphate-based starter pellets were coated with the mixture containing rosuvastatin. Some of them were additionally coated with hydroxypropyl methylcellulose, which was intended to separate the bitter substance and prevent it from coming into contact with the taste buds. The sensor array consisted of 16 prepared sensors with a polymer membrane that had a different selectivity towards rosuvastatin calcium. The main analytical parameters (sensitivity, selectivity, response time, pH dependence of potential, drift of potential, lifetime) of the constructed ion-selective electrodes sensitive for rosuvastatin were determined. The signals from the sensors array recorded during the experiments were processed using Principal Component Analysis (PCA). The results obtained, i.e., the chemical images of the pharmaceutical samples, indicated that the electronic tongue composed of the developed solid-state electrodes provided respective attributes as sensor signals, enabling both of various kinds of ROS pellets to be distinguished and their similarity to ROS bitterness standards to be tested. Full article

The gustatory system is responsible for detecting and evaluating the palatability of the various chemicals present in food and beverages. Taste bud cells, located primarily on the tongue, communicate with the gustatory sensory neurons by means of neurochemical signals, transmitting taste information to the brain. It has also been found that the endocannabinoid system (ECS) may modulate food intake and palatability, and that taste bud cells express cannabinoid receptors. The purpose of this study was to investigate the expression of cannabinoid and cannabinoid-related receptors in the gustatory cells of the papillae vallatae and foliatae of ten piglets. Specific antibodies against the cannabinoid receptors (CB1R and CB2R), G protein-coupled receptor 55 (GPR55), transient receptor potential vanilloid 1 (TRPV1) and ankyrin 1 (TRPA1) were applied on cryosections of lingual tissue; the lingual tissue was also processed using Western blot analysis. Cannabinoid and cannabinoid-related receptors were found to be expressed in the taste bud cells and the surrounding epithelial cells. The extra-papillary epithelium also showed strong immunolabeling for these receptors. The results showed that these receptors were present in both the taste bud cells and the extra-gustatory epithelial cells, indicating their potential role in taste perception and chemesthesis. These findings contributed to understanding the complex interactions between cannabinoids and the gustatory system, highlighting the role of the ECS within taste perception and its potential use in animal production in order to enhance food intake. Full article

Yellow tea (YT), a slightly fermented tea with a unique yellowing process and mellow taste, is becoming widely popular. Currently, the YT includes bud yellow tea (BYT), small-leaf yellow tea (SYT), and large-leaf yellow tea (LYT) based on maturity of raw materials. Previous studies have shown that YT has outstanding potential in preventing metabolic syndrome. However, the distinct effects and mechanisms of different types of YT on ulcerative colitis (UC) are still unclear. This study investigated the effects and mechanisms of continuous or intermittent intervention of three yellow tea water extracts (YTEs) on dextran sulfate sodium (DSS)-induced ulcerative colitis in CD-1 mice. The results showed that YTE intervention significantly improves the syndrome of DSS-induced UC in mice. Mechanistic studies reveal that YTEs increase the expression levels of tight junction (TJ) proteins and reduce the levels of pro-inflammatory cytokines in the colon by inactivating TLR4/NF-κB/NLRP3. YTE treatment protected intestinal barrier integrity and reduced serum lipopolysaccharide (LPS) levels. Interestingly, our results indicate that large-leaf yellow tea (LYT) has a better alleviating effect than BYT and SYT. YTE intervention before DSS administration has a certain degree of preventive effect on ulcerative colitis, while continuous YTE intervention after DSS induction has a significant reversing effect on the damage caused by DSS. Our results indicated that drinking YT may have preventive and therapeutic effect on UC, especially drinking LYT. Full article

Sweet and salty tastes are highly palatable and drive food consumption and potentially uncontrolled eating, but it remains unresolved whether the ability to recognize sweet and salty affects food reward and uncontrolled eating. We investigate the association of sweet and salty taste recognition with liking and wanting and uncontrolled eating. Thirty-eight, mainly female (68%) participants of the Obese Taste Bud study, between 22 and 67 years old, with a median BMI of 25.74 kg/m² (interquartile range: 9.78 kg/m²) completed a taste test, the Leeds Food Preference Questionnaire to assess food reward, the Power of Food Scale (PFS) and the Three-Factor Eating Questionnaire to assess different aspects of uncontrolled eating. Better salty taste recognition predicted greater implicit wanting for high-fat savory foods (β = 0.428, p = 0.008) and higher PFS total (β = 0.315; p = 0.004) and PFS present subscale scores (β = 0.494, p = 0.002). While neither sweet nor salty taste recognition differed between lean individuals and individuals with obesity, those with greater trait uncontrolled eating showed significantly better salty taste recognition (U = 249.0; p = 0.009). Sweet taste recognition did not associate with food reward or uncontrolled eating. Better salty but not sweet taste recognition associates with a greater motivation for, but not liking of, particularly savory high-fat foods and further relates to greater loss of control over eating. Salty taste perception, with taste recognition in particular, may comprise a target to modulate food reward and uncontrolled eating. Full article