7 research outputs found
Comparison of salivary proteome of children with different sensitivities for bitter and sweet tastes: association with body mass index
Background/objectives: Oral sensorial perception is a key aspect in food choices and knowing the mechanisms modulating such perception is of major importance in the context of child obesity, which is reaching high rates in Mediterranean countries. Salivary proteome has been linked to taste sensitivity in adults. The aim of this study was to search for differences in salivary proteomes of children with different bitter or sweet taste sensitivities and to assess if these potential differences are associated with their body mass index percentile (BMI percentile).
Subjects/methods: 387 children aged 8-9 years old were assessed for BMI percentile and classified according to their sensitivity to bitter and sweet tastes, according to their caffeine and sucrose detection thresholds, respectively. Saliva protein composition was compared among taste sensitivity groups, taking into account BMI percentile and gender, using gel-based proteomics approaches, coupled to mass spectrometry for protein identification.
Results: Among the salivary proteins related to bitter taste sensitivity, higher levels of cystatins were observed in bitter-sensitive children, in the case of those of normal weight, and in bitter low-sensitive, in the case of overweight children. For sweetness, the relationship between saliva and taste perception was also dependent on BMI percentile, with several proteins (including salivary cystatins) differing between taste sensitivity groups, with disparities arising between normal-weight and overweight children. Cystatin isoforms A, B and SA were observed to be considerably increased in saliva from obese children.
Conclusions: Salivary proteome is related with sensitivities to bitter and sweet tastes in children, but the association is dependent on BMI percentile and gender
Chemosensate-Induced Modulation of the Salivary Proteome and Metabolome Alters the Sensory Perception of Salt Taste and Odor-Active Thiols
Oral
stimulation with chemosensates was found to trigger changes
in the composition of the salivary proteome and metabolome, which
translate into a functional modulation of odor and taste perception.
Orosensory intervention with 6-gingerol induced a significant increase
in the abundance of salivary sulfhydryl oxidase 1, which was found
to catalyze the oxidative decline of odor-active 2-furfurylthiol,
thus resulting in a decrease in the odorant levels in exhaled breath,
as shown by PTRâMS, and a reduction of the perceived sulfury
after-smell. Therefore, sulfhydryl oxidase 1 may be considered as
a component of a molecular network triggering oral cleansing mechanisms
after food ingestion. Moreover, oral stimulation with citric acid,
followed by targeted metabolomics, was found to induce a strong increase
in salivary concentrations of minerals and, in particular, sodium
ions, whereas the other metabolites were rather unaffected. Because
of the elevated basal levels of salivary sodium after citric acid
stimulation, NaCl test stimuli were perceived as significantly less
salty, most likely due to the decreased sensory contrast. This indicates
the modulation of the salivary proteome and metabolome to be a major
perireceptor event in fine-tuning odor and taste sensitivity
Salivary Proteome Patterns Affecting Human Salt Taste Sensitivity
To
investigate the role of perireceptor events in inter-individual
variability in salt taste sensitivity, 31 volunteers were monitored
in their detection functions for sodium chloride (NaCl) and classified
into sensitive (0.6â1.7 mmol/L), medium-sensitive (1.8â6.9
mmol/L), and nonsensitive (7.0â11.2 mmol/L) subjects. Chemosensory
intervention of NaCl-sensitive (S<sup>+</sup>) and nonsensitive (S<sup>â</sup>) panellists with potassium chloride, ammonium chloride,
and sodium gluconate showed the salt taste sensitivity to be specific
for NaCl. As no significant differences were found between S<sup>+</sup> and S<sup>â</sup> subjects in salivary sodium and protein
content, salivary proteome differences and their stimulus-induced
dynamic changes were analyzed by tryptic digestion, iTRAQ labeling,
and liquid chromatographyâtandem mass spectrometry analysis.
Differences in the salivary proteome between S<sup>+</sup> and S<sup>â</sup> subjects were found primarily in resting saliva and
were largely independent of the dynamic alterations observed upon
salt stimulation. Gene ontology enrichment analysis of key proteins,
i.e., immunoglobulin heavy constant y1, myeloblastin, cathepsin G,
and kallikrein, revealed significantly increased serine-type endopeptidase
activity for the S<sup>+</sup> group, while the S<sup>â</sup> group exhibited augmented cysteine-type endopeptidase inhibitor
activity by increased abundances in lipocalin-1 and cystatin-D, -S,
and -SN, respectively. As proteases have been suggested to facilitate
transepithelial sodium transport by cleaving the y-subunit of the
epithelial sodium channel (ENaC) and protease inhibitors have been
shown to reduce ENaC-mediated sodium transport, the differentially
modulated proteolytic activity patterns observed <i>in vivo</i> for S<sup>+</sup> and S<sup>â</sup> subjects show evidence
of them playing a crucial role in affecting human NaCl sensitivity