Gusto dulce: Percepción, fuentes alimentarias y preferencias

El dulzor es un atributo característico de alimentos y bebidas que contienen azúcares u otros edulcorantes. El uso de azú-cares ha sido reemplazado por otros edulcorantes, a fin de disminuir los efectos nocivos de éstos en diferentes resultados de salud. Sin embargo, se ha sugerido que el gusto dulce, independiente de su origen, podría tener efectos indeseados en la salud. En este artículo se revisan diversos aspectos relacionados con el gusto dulce, desde su percepción, su presencia en alimentos y líquidos, las preferencias innatas y adquiridas por este gusto y los productos que lo aportan. Se analiza además la importancia de estudiar el rol del gusto dulce en la dieta y salud.

Sweetness is a characteristic of foods and beverages that contain sugars or other sweeteners. Sugars have been replaced by other sweeteners to reduce their harmful effects on different health outcomes. However, it has been suggested that the sweet taste, regardless of its origin, could have unwanted effects on health. This article reviews various aspects of sweet taste, from its perception, presence in foods and liquids, innate and acquired preferences for this taste, and the products that provide it. We also analyzed the importance of studying the role of sweet taste in diet and health.

Regulation effect of lipopolysaccharide on the alternative splicing and function of sweet taste receptor T1R2 / 华西口腔医学杂志

OBJECTIVES@#To identify the alternative splicing isoform of mouse sweet taste receptor T1R2, and investigate the effect of lipopolysaccharide (LPS) local injection on T1R2 alternative splicing and the function of sweet taste receptor as one of the bacterial virulence factors.@*METHODS@#After mouse taste bud tissue isolation was conducted, RNA extraction and reverse transcription polymerase chain reaction (PCR) were performed to identify the splicing isoform of T1R2. Heterologous expression experiments @*RESULTS@#T1R2 splicing isoform T1R2_Δe3p formed sweet taste receptors with T1R3, which could not be activated by sweet taste stimuli and significantly downregulated the function of canonical T1R2/T1R3. Local LPS injection significantly increased the expression ratio of T1R2_Δe3p in mouse taste buds.@*CONCLUSIONS@#LPS stimulation affects the alternative splicing of mouse sweet taste receptor T1R2 and significantly upregulates the expression of non-functional isoform T1R2_Δe3p, suggesting that T1R2 alternative splicing regulation may be one of the mechanisms by which microbial infection affects host taste perception.

Estado nutricional y preferencia del sabor dulce en adultos chilenos / Nutritional status and sweet taste preference in Chilean adults

El dramático aumento de la prevalencia e incidencia de la obesidad sugiere que factores ambientales y cambios en el estilo de vida contribuyen de forma importante a su tendencia epidémica. En humanos, se han reportado diferencias interindividuales en los umbrales de detección y preferencia del sabor dulce, lo que podría afectar la ingesta habitual de azúcares, y por ende al estado nutricional. Objetivo: El presente estudio busca determinar la relación entre el estado nutricional y la preferencia al sabor dulce en la comunidad de un establecimiento de educación superior. Método: Muestra fue constituida por estudiantes, funcionarios y docentes, entre 18 y 60 años, pertenecientes a la Universidad Mayor, Sede Temuco. Para determinar preferencia al sabor dulce se empleó prueba organoléptica que mide grado de satisfacción frente a solución dulce, junto a ello se realizaron mediciones de peso y talla para determinar el Índice de Masa Corporal. Resultados: Muestra final comprendió de 319 personas, de las cuales un 30,1% fueron hombres y 69,9% mujeres. No se observaron diferencias significativas en la preferencia hacia las soluciones con mayor concentración de sacarosa según el estado nutricional. Sin embargo, el modelo predictivo desarrollado arrojó que hombres prefieren las soluciones con mayor concentración de azúcar independiente de la edad y estado nutricional. Conclusiones: Es necesario desarrollar nuevos estudios que permitan aclarar si la preferencia al sabor dulce favorece el desarrollo de obesidad y sobrepeso, o si es la composición nutricional de los alimentos procesados o ultraprocesados, lo que está teniendo un mayor impacto negativo en el estado nutricional de la población(AU)

The dramatic increase in the prevalence and incidence of obesity seems to suggest that environmental factors and lifestyle changes are contributing significantly to the epidemic trend of this pathology. In humans, inter-individual differences in the thresholds of preference of sweet taste have been reported, which could affect habitual sugar intake, and therefore the nutritional status. Objective: The present study seeks to determine the relationship between nutritional status and the preference of sweet taste in the population of a higher education establishment. Method: Sample was constituted by students, officials and teachers between 18 and 60 years, belonging to the Universidad Mayor, Temuco. To determine the perception of the sweet taste, an organoleptic test was used that measures the degree of satisfaction with the sweet solution, along with this, weight and height measurements were made to determine the Body Mass Index. Results: Final sample comprised 319 people, of which 30.1% were men and 69.9% women. No significant differences were observed in the preference for solutions with a higher concentration of sucrose according to nutritional status. However, a predictive model developed showed that men prefer the solutions with the highest concentration of sugar regardless of age and nutritional status. Conclusions: It is necessary to develop new studies to clarify whether the preference for sweet taste favors the development of obesity and overweight, or if it is the nutritional composition of processed or ultraprocessed foods, which is having a greater negative impact on the nutritional status of the population.(AU)

La amarga realidad de los edulcorantes no nutritivos: desde una perspectiva global al contexto chileno / The bitter reality of non-nutritive sweeteners: a global perspective applied to the Chilean context

Actualmente los edulcorantes no nutritivos (ENN) son ampliamente usados para endulzar los alimentos en reemplazo de los azúcares simples, con la ventaja de no aportar energía. A pesar de que en general no presentan efectos tóxicos, los estudios epidemiológicos no han podido evidenciar que su uso contribuya a mejorar la pérdida de peso, sino por el contrario, han revelado que los ENN pueden inducir alteraciones metabólicas como intolerancia a la glucosa. Estudios in vivo e in vitro han mostrado que muchos ENN activan a receptores del sabor dulce no sólo en los botones gustativos, sino que también en los receptores presentes en tejidos como el adiposo y pancreático, interfiriendo con su función normal. Además, el consumo ENN se ha asociado a alteraciones de la composición de la microbiota intestinal que conducen a una respuesta inflamatoria de bajo grado. La nueva evidencia disponible sobre los ENN hace necesario evaluar el uso cada vez más intenso de los ENN en Chile. Debido a que el gusto exacerbado por el sabor dulce que cultivamos desde la infancia es un potente catalizador del uso de ENN, proponemos que una oportuna educación del sentido del gusto puede contribuir a mejorar las elecciones alimentarias.

Currently, non-nutritive sweeteners (NNS) are widely used to sweeten foods instead of simple sugars, as they possess the advantage of not contributing to energy intake. Although they do not present toxic effects in general, epidemiological studies have not been able to show benefits when they are used in weight loss programs. However, they could induce metabolic alterations such as glucose intolerance. In vivo and in vitro studies have shown that many NNSs activate sweet taste receptors not only in the taste buds, but also in receptors present in adipose and pancreatic tissues, interfering with their normal function. In addition, NNS consumption has been associated with an alteration in the composition of the gut microbiota that leads to a low-grade inflammatory response. Due to the wide use of NNS in Chile, it is necessary to evaluate the potential health effects of using NNS in the Chilean population. We propose that a timely education of the sense of taste can contribute to moderating the preference for higher levels of sweet taste that humans develop in childhood, which could help to improve food choices.

Presence of carbohydrate binding modules in extracellular region of class C G-protein coupled receptors (C GPCR): An in silico investigation on sweet taste receptor

Sweet taste receptor (STR) is a C GPCR family member and a suggested drug target for metabolic disorders such asdiabetes. Detailed characteristics of the molecule as well as its ligand interactions mode are yet considerably unclear due toexperimental study limitations of transmembrane proteins. An in silico study was designed to find the putative carbohydratebinding sites on STR. To this end, a-D-glucose and its a-1,4-oligomers (degree of polymerization up to 14) were chosen asprobes and docked into an ensemble of different conformations of the extracellular region of STR monomers (T1R2 andT1R3), using AutoDock Vina. Ensembles had been sampled from an MD simulation experiment. Best poses were furtherenergy-minimized in the presence of water molecules with Amber14 forcefield. For each monomer, four distinct bindingregions consisting of one or two binding pockets could be distinguished. These regions were further investigated withregard to hydrophobicity and hydrophilicity of the residues, as well as residue compositions and non-covalent interactionswith ligands. Popular binding regions showed similar characteristics to carbohydrate binding modules (CBM). Observationof several conserved or semi-conserved residues in these binding regions suggests a possibility to extrapolate the results toother C GPCR family members. In conclusion, presence of CBM in STR and, by extrapolation, in other C GPCR familymembers is suggested, similar to previously proposed sites in gut fungal C GPCRs, through transcriptome analyses. STRmodes of interaction with carbohydrates are also discussed and characteristics of non-covalent interactions in C GPCRfamily are highlighted.

Effect of Astragalus Polysaccharide on Sweet Taste Receptor Pathway in Intestine of Rat Model Induced by High-sugar and High-fat Diet / 中国实验方剂学杂志

Objective:To observe the effect of astragalus polysaccharide (APS) on taste receptor 1 member 2 (T1R2)/taste receptor 1 member 3 (T1R3) sweet taste receptor pathway in intestine of rat model induced by high-sugar and high-fat diet. Method:SD rats were randomly divided into normal group, high-sugar and high-fat group and astragalus polysaccharide group. Rats in high-sugar and high-fat group and astragalus polysaccharide groups were fed with high-sugar and high-fat diet for 16 weeks, while rats in astragalus polysaccharide group were fed with APS (0.7 g·kg-1, per day) for 8 weeks during this period. Serum samples were collected to determine the levels of fasting blood glucose, total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C). Intestinum tenue was collected to determine mRNA expressions of T1R2/T1R3, α-gustducin (Gα gust), transient receptor potential cation channel subfamily member 5 (TRPM5) and proglucagon (PG) gene by Real-time PCR, and protein expressions of T1R2, Gα gust and glucagon-like peptide-1 (GLP-1) protein by Western blot. Result:Rats in high-sugar and high-fat group had significantly higher levels of TC, TG and LDL-C, and lower HDL-C level in serum than those in normal group (Pα gust and PG genes in intestine, were significantly down-regulated in high-sugar and high-fat group (PPα gust, TRPM5 and PG genes in intestine were significantly up-regulated in astragalus polysaccharide group (Pα gust and GLP-1 protein expressions was consistent with that of T1R2, Gα gust and GLP-1 mRNA expressions. Protein expressions of T1R2, Gα gust and GLP-1 and mRNA expression of T1R3 were significantly lower in astragalus polysaccharide group than those of control group (PConclusion:APS could improve disturbance of lipid metabolism and impairment of intestinal sweet taste receptor pathway for rat model induced by high-sugar and high-fat diet.

Role of sweet taste receptors in the activation of NLRP3 inflammasome signaling in diabetic kidney disease / 中华内分泌代谢杂志

Objective@#To investigate the role of sweet taste receptors(STRs)in the activation of reactive oxygen species (ROS)-NLRP3 inflammasome signaling in diabetic kidney disease(DKD).@*Methods@#DKD mouse were established by high-fat diet and streptozotocin. After mouse glomerular mesangial cells(GMCs)were exposed to high glucose, STRs(T1R2/T1R3)and associated signaling components and NLRP3 inflammasome signaling components expressions were detected. After GMCs were treated with STRs inhibitor lactisole, the production of ROS was detected and the role of STRs in the activation of NLRP3 signaling was investigated.@*Results@#Under high glucose condition, the expressions of T1R2, T1R3, Gα-gustducin, phospholipase C-β2, and TRPM5 were significantly decreased in vivo and in vitro(all P<0.05)and ROS-NLRP3 signaling was activated(all P<0.05). Lactisole significantly mitigated the production of ROS and the activation of NLRP3 inflammasome signaling stimulated by high glucose in GMCs(all P<0.05).@*Conclusion@#The STRs(T1R2/T1R3)-mediated signaling pathway may be involved in the regulation of ROS-NLRP3 inflammatory signaling, suggesting that STRs may act as new therapeutic targets of DKD. (Chin J Endocrinol Metab, 2018, 34: 587-593)

Expression of sweet-taste of Chinese materia medica and its application in clinical compatibility / 中草药

The connotation of traditional Chinese medicine and base resource of sweet-taste herbs were summarized. At the same time, the distribution between sweet-taste herbs and four properties, meridian entry, and other herb property theory was analyzed. Then, the gustatory receptor, taste representation, and research on material basis of sweet-taste herbs were elaborated. Finally, the clinical applications of compatibility methods of sweet herbs were described, which will provide the references to guide clinical applications of the theory of bitter-taste herbs better.

Seleção de aptâmeros que se ligam ao receptor humano para o gosto doce / Screening for aptamers that bind to the human sweet taste receptor (hT1R2/hT1R3)

Foi demonstrado que o gosto doce é transduzido por receptores acoplados a proteína G classe III (GPCRs), T1R2 e T1R3. Essas proteínas exibem longas extremidades amino-terminais que formam um domínio de ligação globular extracelular. Elas são expressas em células associadas ao gosto (células epiteliais que constituem os botões gustativos nas papilas gustativas), que respondem a moléculas associadas ao gosto doce. Quando T1R2 e T1R3 são co-expressas em células heterólogas, elas respondem, como heterômeros, a uma série de açúcares, alguns D-aminoácidos, edulcorantes artificiais e proteínas doces. Foi também demonstrado que o receptor humano T1R2/T1R3 para o gosto doce apresenta múltiplos sítios de ligação. Para melhor compreender a estrutura desse receptor e responder à pergunta de como um único quimiorreceptor pode ser responsivo a uma variedade de ligantes, foi utilizada a abordagem denominada evolução sistemática de ligantes por enriquecimento exponencial (SELEX) para isolar, a partir de uma biblioteca combinatória de oligonucleotídeos, aptâmeros de RNA resistentes a nuclease que se ligam ao receptor humano para o gosto doce com alta afinidade. Após um enriquecimento de doze ciclos do pool original de RNA contendo em torno de 1013 sequências diferentes (contra preparações de membrana de células HEK293T que expressam hT1R2/hT1R3) e outros ciclos de contrasseleção negativa (para eliminar moléculas de RNA que se ligam de forma inespecífica à membrana de nitrocelulose e a outras proteínas diferentes do alvo, ou seja, proteínas de membrana de células HEK293T selvagem), realizou-se a transcrição reversa do RNA seguida de amplificação por PCR e sequenciamento. Aptâmeros do ciclo 12 com sequências consenso foram selecionados, e a ligação de alguns deles com hT1R2/hT1R3 foi então avaliada. Cinco desses aptâmeros mostram claramente uma maior afinidade por células HEK293T que expressam hT1R2/hT1R3. Como segunda parte desta tese, estudamos outro receptor, denominado CD36, que, como o receptor T1R2/T1R3, é expresso na língua. Estudos indicam que ele age como receptor gustativo de gordura. Neste trabalho, verificamos que essa proteína é expressa em uma subpopulação de neurônios olfatórios presentes no epitélio olfatório, indicando que ela pode ter também uma função olfatória, ainda não caracterizada

It has been shown that sweet taste is transduced by the Class III G Protein-Coupled Receptors (GPCRs) T1R2 and T1R3, which show long N-termini that form a globular extracellular ligand-binding domain. These receptors are expressed in the taste cells (epithelial cells that constitute the taste buds in taste papillae) that respond to sweet tastants, and when T1R2 and T1R3 are coexpressed in heterologous cells, they respond, as heteromers, to a series of sugars, some D-amino acids, artificial sweeteners and sweet proteins. It has also been demonstrated that the sweet taste receptor has multiple binding sites. In order to better understand the structure of this receptor and answer the question of how a single chemoreceptor can respond to a variety of ligands, we used the combinatorial oligonucleotide library screening approach, denominated Systematic Evolution of Ligands by Exponential Enrichment (SELEX), to isolate nuclease-resistant RNA aptamers that bind to the human sweet taste receptor with high affinity. Following a twelve round enrichment of the previous random RNA pool containing around 1013 different sequences (against membrane preparations of hT1R2/hT1R3-expressing HEK293T cells) and negative counterselection cycles (to eliminate RNA molecules that bind nonspecifically to the nitrocellulose membrane and to proteins other than the target, that is, HEK293T cells membrane proteins), the RNA was reverse-transcribed for DNA sequencing. Aptamers from cycle 12 with consensus sequences were selected, and the binding of some of them to the human sweet taste receptor was then evaluated. Five out of the aptamers clearly show greater affinity for hT1R2/hT1R3-expressing HEK293T cells than for hT1R2/hT1R3-non-expressing HEK293T cells. In this thesis we have also analyzed another receptor, denominated CD36, which is also expressed in the tongue. Studies indicate that it acts as a receptor for fat. In this work, we found that CD36 is expressed in a subset of the olfactory neurons localized in the olfactory epithelium, indicating that it may also have an as yet uncharacterized olfactory function

Sweet Taste-Sensing Receptors Expressed in Pancreatic beta-Cells: Sweet Molecules Act as Biased Agonists

The sweet taste receptors present in the taste buds are heterodimers comprised of T1R2 and T1R3. This receptor is also expressed in pancreatic beta-cells. When the expression of receptor subunits is determined in beta-cells by quantitative reverse transcription polymerase chain reaction, the mRNA expression level of T1R2 is extremely low compared to that of T1R3. In fact, the expression of T1R2 is undetectable at the protein level. Furthermore, knockdown of T1R2 does not affect the effect of sweet molecules, whereas knockdown of T1R3 markedly attenuates the effect of sweet molecules. Consequently, a homodimer of T1R3 functions as a receptor sensing sweet molecules in beta-cells, which we designate as sweet taste-sensing receptors (STSRs). Various sweet molecules activate STSR in beta-cells and augment insulin secretion. With regard to intracellular signals, sweet molecules act on STSRs and increase cytoplasmic Ca2+ and/or cyclic AMP (cAMP). Specifically, when an STSR is stimulated by one of four different sweet molecules (sucralose, acesulfame potassium, sodium saccharin, or glycyrrhizin), distinct signaling pathways are activated. Patterns of changes in cytoplasmic Ca2+ and/or cAMP induced by these sweet molecules are all different from each other. Hence, sweet molecules activate STSRs by acting as biased agonists.

Lifestyle, dietary habits and consumption pattern of male university students according to the frequency of commercial beverage consumptions

Because excessive consumption of sugar-sweetened beverages may reduce the quality of nutritional intake, this study examined the consumption patterns of commercial beverages, lifestyle, dietary habits, and perception of sweet taste. Participants were 407 male university students in Kyeonggido, Korea, and information was collected by self-administered questionnaire. Among them, 58 nonsmokers volunteered to participate in the taste test. Participants were divided into three groups according to the frequency of commercial beverage consumptions: 120 rare ( 3 servings/week) consumption groups. More subjects from the rare consumption group chose water, tea, and soy milk, and more from the frequent consumption group chose carbonated soft drinks and coffee (P = 0.031) as their favorite drinks. Frequent consumption group consumed fruit juice, coffee, and sports and carbonated soft drinks significantly more often (P = 0.002, P = 0.000, P = 0.000, respectively), but not milk and tea. Frequent consumption group consumed beverages casually without a specific occasion (P = 0.000) than rare consumption group. Frequent drinking of commercial beverages was associated with frequent snacking (P = 0.002), meal skipping (P = 0.006), eating out (P = 0.003), eating delivered foods (P = 0.000), processed foods (P = 0.001), and sweets (P = 0.002), and drinking alcoholic beverages (P = 0.029). Frequent consumption group tended to have a higher threshold of sweet taste without reaching statistical significance. The results provide information for developing strategies for evidence-based nutrition education program focusing on reducing consumption of unnecessary sugar-sweetened commercial beverages.

The Role of the Sweet Taste Receptor in Enteroendocrine Cells and Pancreatic beta-Cells

The sweet taste receptor is expressed in taste cells located in taste buds of the tongue. This receptor senses sweet substances in the oral cavity, activates taste cells, and transmits the taste signals to adjacent neurons. The sweet taste receptor is a heterodimer of two G protein-coupled receptors, T1R2 and T1R3. Recent studies have shown that this receptor is also expressed in the extragustatory system, including the gastrointestinal tract, pancreatic beta-cells, and glucose-responsive neurons in the brain. In the intestine, the sweet taste receptor regulates secretion of incretin hormones and glucose uptake from the lumen. In beta-cells, activation of the sweet taste receptor leads to stimulation of insulin secretion. Collectively, the sweet taste receptor plays an important role in recognition and metabolism of energy sources in the body.

The Effect of Lifestyle, Dietary Habit, Food Preference and Eating Frequency on Sweet Taste Sensitivity and Preference of the Middle School Students

This study was conducted to determine factors affecting detection threshold and the optimally-preferred concentration for sweet taste, since investigation into factors decreasing sensitivity or increasing preference for sweet taste is important to prevent overconsumption of simple sugar. Subjects were 70 first-grade middle school students in the Gyeonggi- Do. The detection threshold concentration of sucrose solution and the optimally-preferred sucrose concentration of omija jelly were determined by sensory evaluation. A self-administered questionnaire was used to obtain the information regarding health-related lifestyle practices, dietary habits, preference for and eating frequency of Westernized foods and frequencies of eating foods other than home-made. The detection threshold concentration of sucrose solution and the optimally-preferred sucrose concentration of omija jelly of the subjects were 0.204% and 14.44%, respectively. Subjects who exercise less ( or = 3/week), type of breakfast rather than traditional Korean meal and frequent eating out and buying foods from school tuck-shop tended to have higher sweet taste threshold. There was significant positive correlation between the sucrose threshold concentration and fried chicken preference or eating frequency of hamburger. Those who exercise less ( or = 4 out of 10) behavioral or psychological stress symptoms and who had early getting-up time (before 7 am). There was significant positive correlations between the optimally-preferred sweetness of omija jelly and pizza preference, instant noodle eating frequency or sum of eating frequencies of five fast foods. From the results of this study, it was suggested that middle school students should make efforts to stop skipping meals, exercise more, eat Korean traditional breakfast and reduce the frequencies of eating out and using instant/fast foods in order to prevent overconsumption simple sugar.