Sensibilité orale au gras chez l'homme : liens avec la composition salivaire

La perception du gras chez l’homme est un phénomène complexe du fait de sa nature multi-sensorielle impliquant la perception de la texture, la perception aromatique mais également la perception gustative. Cette dernière a été suggérée après l’identification de récepteurs aux acides gras au niveau des bourgeons gustatifs. Par ailleurs, des études récentes ont montré que la sensibilité au gras est variable entre individus. Des facteurs génétiques ou environnementaux pourraient expliquer en partie cette variation interindividuelle. Cependant, la salive pourrait aussi jouer un rôle dans cette perception. En effet, elle contient des molécules capables d’interagir avec le gras comme la lipase et les lipocalines. C’est aussi un fluide complexe qui contient une large diversité de protéines et de métabolites. De plus, sa régulation est complexe et peut varier à la suite d’une stimulation. En effet, des études récentes ont montré que le protéome salivaire est modifié à la suite d’une stimulation par des molécules correspondant aux saveurs primaires. Dans ce contexte, l’objectif de ce travail était de déterminer dans un premier temps s’il existe des liens entre la composition salivaire et la sensibilité gustative à un acide gras libre: l’acide oléique. Le deuxième objectif était d’étudier les modifications de la composition salivaire à la suite d’une stimulation gustative par l’acide oléique. Pour ceci deux approches ont été utilisées: des approches ciblées (activité enzymatique, capacité antioxydante etc) et des approches non-ciblées (protéomique et métabolomique). Deux groupes de treize sujets (hyper et hyposensible au goût de l’acide oléique) ont été sélectionnés à partir d’un panel de 73 participants. Leur salive a été collectée au repos et après stimulation par l’acide oléique. Les résultats montrent que la composition de la salive au repos est liée à la sensibilité à l’acide oléique. En effet, des marqueurs liés à la perception du goût ont été identifiés au sein du groupe des hypersensibles (anhydrase carbonique, cystatines et zinc alpha 2 glycoprotéine), alors que des marqueurs pouvant indiquer une activité bactérienne élevée (acides organiques) ont été identifiés au sein du groupe des hyposensibles. Par ailleurs, la composition de la salive collectée après stimulation par l’acide oléique est également modifiée et ces modifications sont différentes pour les sujets hyper et hyposensibles à cette stimulation.Human fat perception has recently triggered particular interest as it was shown that it does not only involve aroma and texture perception but also taste perception. The latter was supported by the presence of free fatty acids (FFA) taste receptors on the tongue. Recent studies have shown that fat taste sensitivity is variable among individuals. This inter-individual variation could be linked to genetic or environmental factors. However, saliva could also play a role in this perception. The role of saliva in taste perception is increasingly recognized. Saliva contains molecules able of interacting with fat such as lipase and lipocalin. It is also a complex fluid which contains a large diversity of proteins and metabolites. Its regulation is also complex and its composition may vary after a sensory stimulation. Indeed, studies have shown that when giving primary taste stimulations, the whole salivary proteome is modified. Thus, the first aim of the present work was to use both targeted (enzymatic activity, antioxidant capacity etc) and untargeted approaches (proteomics and metabolomics) to identify links between taste sensitivity to a fatty acid, oleic acid, and the salivary composition. The second aim was to investigate whether the salivary composition is modified after an oral stimulation by oleic acid.Two groups of thirteen male subjects (highly and weakly sensitive to the taste of oleic acid) were selected from an initial panel of 73 healthy participants. Their whole saliva was collected in two ways; the first without stimulation in order to study the links between oral sensitivity to oleic acid and saliva composition and the second using a stimulation by the same fatty acid in order to study potential modifications of saliva composition depending on sensitivity. Results show that salivary composition is linked to oral fatty acid perception. Markers previously reported as associated to taste perception were determined in the highly sensitive group (carbonic anhydrase, Zinc Alpha 2 glycoprotein and cystatins) while markers (organic acids) indicating a higher bacterial load were identified in weakly sensitive group. Furthermore, results obtained after stimulation by oleic acid suggest that saliva composition is modified, which confirms its dynamic nature. As different modifications were observed for the highly and weakly sensitive group, our results suggest that saliva is not only modified after a stimulation but also depending on the sensitivity to that particular stimulation

Oral fat sensitivity in humans: links to saliva composition before and after stimulation by oleic acid

WOS:000324267300002 ; ISSN = 1936-5802International audienceFat perception is a complex sensation dependent on different sensory cues, such as texture and olfaction, and also potentially taste. In addition, saliva can interact with dietary fat during its consumption and influence the perception of fatty acids. Because previous studies had identified subjects who were hyper- and hyposensitive to the perception of free fatty acids, the first aim of this work was to study whether saliva composition is different in groups of subjects having low and high oral sensitivity to a free fatty acid, oleic acid (C18:1). The second aim was to determine whether oral stimulation with C18:1 could modify the composition of saliva. To verify these hypotheses, two groups of individuals were selected from a panel of 73 subjects: one group sensitive + to C18:1 (n = 12) and one sensitive - to C18:1 (n = 13). Overall, no differences were found in the saliva characteristics between the two groups. However, significant differences after C18:1 stimulation when comparing to a control stimulation were observed in the sensitive + group: in this group, the increase in antioxidant capacity and the decrease in lipolytic activity were significant, while it was not in the sensitive - group although the median values were similar for this last variable in the two groups. This would suggest that the response given by the salivary system to fatty acid stimulation is different in groups of subjects having low and high oral sensitivity to C18:1

Is saliva composition linked to fat taste sensitivity in human?

Is saliva composition linked to fat taste sensitivity in human?. 10. european symposium on Saliv

(L14) Effect of fat on saliva composition: Relation with human fat sensitivity

Abstract of oral presentationFat consumption is described as one of the major reasons for the obesity epidemic. Fat sensitivity may. be one of the causes as a recent study shows that subjects hyposensitive to fat perception have a higher. Body Mass Index value than hypersensitive ones1. Moreover interest on fat perception in the mouth has. grown especially after the discovery of fat taste receptors on the tongue and their possible implications in. fat metabolism. This gives another dimension for fat perception as it was always thought to have only. olfactory and textural characteristics. However, this perception is still unclear and other factors could play. a role in it. During consumption, the first fluid that is in contact with food is saliva. Saliva has many roles in the. oral cavity including food perception. Moreover, studies showed that saliva composition can be modified. specifically by different sensory stimulus. In addition, recent works showed a relationship between human. fat perception and saliva composition2. Consequently, the main purpose of this study is to establish. whether salivary biochemical composition is modified by a fat stimulus and whether or not this. composition is different for subjects hyper and hypo sensitive to this stimulus. In order to study the fat sensitivity relation with saliva composition, 2 groups of male subjects. (hypersensitive and hyposensitive) were selected from an initial group of 73 healthy participants. The. selection was done using a modified 3 Alternative Forced Choice sensory test on 2 types of emulsion: the. first one containing a low concentration of oleic acid (OA) for the selection of the hypersensitive group. and the second one with a high OA concentration for the hyposensitive group. Following this recruitment,. subjects from both groups came on 6 occasions, and their saliva was collected at rest, after stimulation by. a control and after stimulation by OA. The samples were analyzed for their biochemical composition (lipolytic, amylolitic, proteolysis activities,. antioxidant capacity, and protein concentration). The results show no significant difference between the 2. groups for their saliva at rest. As for the stimulated saliva, the hypersensitive group presents a higher. antioxidant capacity and a lower lipolytic activity after stimulation by OA compared to control when. there is no significant change in the hyposensitive group. This suggests that there is a specific response of. saliva to a fat stimulus depending on the sensitivity of the person

Are metabolomics and proteomic salivary profiles related to human taste sensitivity to oleic acid?

Are metabolomics and proteomic salivary profiles related to human taste sensitivity to oleic acid?. 2. International congress of translational research in human nutrition "Integrative Approaches in Nutrition Research

Markers of oral fat sensitivity; a combined proteomics and metabolomics approach

Markers of oral fat sensitivity; a combined proteomics and metabolomics approach. 1. International symposium on profilin

Is saliva composition related to oral fat sensitivity or exposure?

To characterize the taste of drinking waters, Teillet et al. (2010) used first a free sorting task and then defined the Polarized Sensory Positioning (PSP) technique as a substitute better suited to industrial constraints. They conclude that Total Dissolved Solids (TDS) is the main driver of water taste. Puget et al. (2010) found, based on triangular tests, that differences in mineral profiles can also generate taste differences. The research reported in this paper aims at assessing relative importance of TDS and mineral profile in water taste and at the same time comparing free sorting task, PSP and triangular test suitability for addressing this issue. Three levels of TDS (low, medium and high) were chosen to match the 3 commercial waters used as poles in Teillet (2010). Then each of these 3 waters were enriched in either Na+, Ca2+, Mg2+ or Cl- producing 4 different mineral profiles at a given TDS level. The set of the 3 commercial and 12 experimental waters can be seen as a 3x5 factorial design crossing 3 levels of TDS with 5 mineral profiles. A panel of 100 consumers did free sorting task, PSP and 45 triangular tests on these 15 waters in 6 sessions. Results confirmed that TDS is definitely a more important driver of water taste than mineral profile even though some differences between mineral profiles were found, especially for medium and high TDS levels. Free sorting task, contrarily to triangular tests, was the method which showed a stronger TDS effect to the expense of a weaker mineral profile effect. The latter was better found with triangular test, whereas PSP behaved in between free sorting task and triangular tests. Although results of the three methods were never discordant, free sorting task seems to overlook the most subtle mineral profile differences found by triangular test, whereas PSP appears as a sort of compromise with an experimental cost 4 times smaller than the triangular test one

Are metabolomics and proteomic salivary profiles related to human taste sensitivity to oleic acid?

Are metabolomics and proteomic salivary profiles related to human taste sensitivity to oleic acid?. 2. International congress of translational research in human nutrition "Integrative Approaches in Nutrition Research

Salivary markers of taste sensitivity to oleic acid: a combined proteomics and metabolomics approach

International audienceSaliva is a biological fluid playing numerous roles in the oral cavity and increasingly considered as a source of markers. The role of saliva in sensory perception has been known for years but it is only recently that its potential role in oral fatty acids (FA) perception has been suggested. The aim of the present work was to study the relationships between taste sensitivity to oleic acid and the salivary proteome (2D electrophoresis) and metabolome (H-1 NMR). This was achieved by comparing saliva from two groups of subjects, highly (sensitive+) and weakly sensitive (sensitive-) to the taste of oleic acid. Partial least squares-discriminant analyses (PLS-DA) were used to model the relationship between sensitivity to C18:1, and the proteome and metabolome data. The two groups could be discriminated by ten spots. In particular, cystatin SN, cystatin D, zinc-alpha-2-glycoprotein and carbonic anhydrase 6 were overexpressed in the sensitive+ group. The latter result was confirmed by ELISA. The overexpression of these proteins, which have been associated to taste perception, supports the argument that C18: 1 is perceived by the taste system. The two groups could also be discriminated on the basis of eight metabolites, with FA, FA/proline, lysine and FA/pyruvate overexpressed in the sensitive+ group and acetate, leucine/isoleucine and butyrate overexpressed in the sensitive-group. The overexpression of these metabolites suggests a higher bacterial load in this group which could be implicated in perception of FAs

Nutri-metabolomics applied to taste perception phenotype: Human subjects with high and low sensitivity to taste of fat differ in salivary response to oleic acid

Saliva has different functions in the mouth and is involved, for example, in taste perception. Saliva composition can also be modified rapidly by taste stimulation. It remains unclear, however, whether the perceived intensity of a tastant may modulate this response. Based on increasing evidence that fat can be perceived by the taste system and that fat taste perception may be associated with fat intake, the aim of this work was to study if stimulation by a fatty acid (oleic acid) modifies saliva composition differently in subjects highly (sensitive+) or weakly (sensitive−) sensitive to that taste. For that purpose, saliva of two groups of subjects was collected after stimulation by either a control emulsion or an emulsion containing 5.61 mM oleic acid. Saliva was analyzed by 2D electrophoresis and 1H NMR spectroscopy. The results show that sensitive+ and sensitive− subjects differ in their salivary response in terms of proteome and metabolome composition. Oppositely to sensitive− subjects, sensitive+ subjects responded to oleic acid by increased abundance of polymeric immunoglobulin receptor, rab GDP dissociation inhibitor beta, and organic acids, and decreased abundance of metabolites characteristic of mucins. The results highlight that modification of saliva composition by taste stimulation may be modulated by taste perception