Gastrointestinal Tract
Pritam S. Sahota, James A. Popp, Jerry F. Hardisty, Chirukandath Gopinath, Page R. Bouchard in Toxicologic Pathology, 2018
The taste buds are composed of epithelial cells that are specialized gustatory sensory cells and are organized into filiform, conical, fungiform, foliate, and circumvallate papillae (Boughter et al. 1997; Abayomi et al. 2009). A wide range of medications impact taste sensation; with significant impact on health as well as potential efficacy of drugs; but until recently, little was known about the biology of taste or how to study its changes in a preclinical setting. Recent advances include molecular insights in renewal of taste buds (Barlow 2015) and suggestions on systematic evaluation of potential changes in-life as well as morphologically (Wang et al. 2017). Figure 11.1 provides an outline of taste bud distribution in rodents. Exposing tongues to either methylene blue, toluidine blue, or food dyes facilitate the recognition of taste bud distribution in small as well as large animal species. Figure 11.2 provides a systematic approach for sampling of tongue targeting a large population of taste buds. The architecture of a prototype taste bud is schematically represented in Figure 11.3. Components of the taste buds could be further interrogated by using molecular markers for cytokeratins as a pan-taste bud marker, GNAT3 for Type II cells, and PGP9.5 for nerve components (Wang et al. 2017). Decision, when a detailed evaluation of taste buds is warranted, may be based on literature review of similar compounds and/or the specific targets of drug candidates.
Management of residual physical deficits
Mark J. Ashley, David A. Hovda in Traumatic Brain Injury, 2017
Taste is detected by taste cells in the mouth involving the tongue, palate, pharynx, epiglottis, and upper third of the esophagus. Taste buds on the tongue detect molecules on the anterior two thirds of the tongue through the taste fibers of cranial nerve VII (facial nerve). The afferent portion of cranial nerve IX (glossopharyngeal nerve) controls the sense of taste for the posterior one third of the tongue. The palate taste buds are innervated by a branch of cranial nerve VII and the epiglottis and esophagus by branches of cranial nerve X (vagus nerve). Taste sensory fibers enter the medulla of the brain stem and transmit into the thalamus. Gustatory functions detect four basic stimuli: bitter, salty, sour, and sweet. Taste buds responding to each of the four basic stimuli are found in all regions of the tongue. Most food flavors are derived from information coming through the olfactory system. Molecules are sent into the back of the nasal cavity by cheeks, tongue, and throat movements.
Physiology of Swallowing
John C Watkinson, Raymond W Clarke, Terry M Jones, Vinidh Paleri, Nicholas White, Tim Woolford in Head & Neck Surgery Plastic Surgery, 2018
Taste buds are the receptors for taste and are located on the surface of the tongue, soft palate and epiglottis. Each taste bud contains approximately 50–100 cells and has a life span of 10–14 days, and they are under constant regeneration.61 They mature into one of three types of taste cell: type I detects salt; type II sweet, bitter and umami; and type III sour.62 Saliva facilitates the movement of taste molecules to the taste bud and its composition is important for taste perception. Taste-related impulses are transmitted via the facial, glossopharyngeal and vagus nerves to the olfactory area of the cortex. The biomechanical swallowing response can alter with different taste flavours. For example, a sour bolus (e.g. lemon juice) may increase oral tongue pressures and tongue-to-palate contact times, although some dispute this.63, 64 Furthermore, a sour bolus seems to have a longer transit and clearance duration in the distal oesophagus.65, 66
Single nucleotide polymorphisms of taste genes and caries: a systematic review and meta-analysis
Published in Acta Odontologica Scandinavica, 2021
Luiz Alexandre Chisini, Mariana Gonzalez Cademartori, Marcus Cristian Muniz Conde, Francine dos Santos Costa, Luana Carla Salvi, Luciana Tovo-Rodrigues, Marcos Britto Correa
Dental caries is a complex disease strongly linked to biological, socioeconomic, behavioural and cultural components. In this way, treatments not addressing this multifactorial and amplified approach tend to fail [5–7]. Biological components are mainly linked with low hygiene habits, low exposure to fluoride and high consumption of fermentable carbohydrates [5,6]. In this way, some studies have directed efforts to understand possible factors that may influence dietary preferences among individuals [8,9]. They have indicated a biological plausibility to a predisposition of genetic and non-genetic eating behaviours, which determine a different taste perception for each individual [10–12]. Authors suggest the existence of some taste genes that influence the gustative perception as well as some factors (such as life stage, physical activity, and gum microbiota) which can co-exist for the determination of gustatory perception.
Individual Differences in Chemosensory Perception Amongst Cancer Patients Undergoing Chemotherapy: A Narrative Review
Published in Nutrition and Cancer, 2022
Alba Ruiz-Ceamanos, Charles Spence, Jordi Navarra
Smell can be experienced in one of two importantly different ways: orthonasal and retronasal (23, 24). Orthonasal olfaction occurs when we smell external aromas from the environment, while retronasal olfaction occurs when volatile aromatic odor molecules are pulsed out of from the back of the nose, especially when we swallow (e.g., when we eat or drink; see 25, 26). In the latter case, one may note that smell and taste are activated at more or less the same time, thus hindering people’s ability to distinguish between the respective inputs that are attributable to each of the senses. On the other hand, taste (gustation) refers exclusively to what can be distinguished from the stimulation of sensory receptors in the oral cavity that code for basic tastes including bitter, sour, sweet, salt, and umami. These sensations appear when a substance activates certain receptors located in the mouth (though see also 27). Finally, flavor refers to a multisensory perception of food or drink involving not only taste, but also retronasal smell (see 28) and, on occasion, the trigeminal nerve (the nerve responsible for the face and motor functions that provides sensations such as temperature, astringency, or pungency; 29) as well.
Amoxicillin chewable tablets intended for pediatric use: formulation development, stability evaluation and taste assessment
Published in Pharmaceutical Development and Technology, 2021
Maria S. Synaridou, Paraskevi Kyriaki Monou, Constantinos K. Zacharis, Dimitrios G. Fatouros, Irene Panderi, Catherine K. Markopoulou
Taste, smell and texture are important factors for any medicine administered orally while, their dissolution rate and the ability to keep drug at the site of absorption are important for peroral administration. Taste sensations arise from stimulation of specialized cells grouped in small clusters called taste buds which exist on the front of the tongue, in folds on the side and in circular grooves on the back of the tongue surface. Undesirable flavor is one of the primary factors determining patients’ non-compliance. Children represent a special group of the population exhibiting difficulties in swallowing medication in tablet form (Gala and Chauhan 2014). Nowadays, the new perception of pharmaceutical technology is that the flavor of an orally administered formulation should be sufficiently pleasant, especially when it is intended for pediatric use. Thus, regulatory authorities, such as the European Formulation Initiative (EuPFI), have recognized the importance of masking the unpleasant flavor of the active pharmaceutical ingredient (API), whereas the European Medicines Agency (EMEA) (EC 2008; EMEA 2006) acknowledge that medicinal products should be made available in age-related formulations (Davies and Tuleu 2008). Pediatric patients with long-term illness requiring continuing medication may be persuaded and trained to take solid dosage forms from a relatively early age of 4–5 years.
Related Knowledge Centers
- Biochemistry
- Mouth
- Perception
- Taste Bud
- Taste Receptor
- Trigeminal Nerve
- Sensory Nervous System
- Tongue
- Sense of Smell
- Flavoring