Midori Sakai

Bio: Midori Sakai is an academic researcher. The author has contributed to research in topics: TAS2R38 & Taste. The author has an hindex of 1, co-authored 1 publications receiving 2 citations.

Normal taste acuity and preference in female adolescents with impaired 6-n-propylthiouracil sensitivity.

Abstract: This study was conducted to determine the relationship between 6-n-propylthiouracil sensitivity and taste characteristics in female students at Nara Women's University. Participants (n=135) were screened for 6-npropylthiouracil sensitivity using a taste test with 0.56 mM 6-n-propylthiouracil solution, and the sensitivity was confirmed by an assay for the bitter-taste receptor gene, TAS2R38. Based on the screening results, 33 6-npropylthiouracil tasters and 21 non-tasters were enrolled. The basic characteristics that are thought to influence taste acuity, including body mass index, saliva volume and serum micronutrient concentrations (iron, zinc and copper), were similar between the two groups. In an analysis using a filter-paper disc method, there were no differences in the acuity for four basic tastes (sweet, salty, sour and bitter) between 6-n-propylthiouracil tasters and non-tasters. In addition, the taste preference for the four basic tastes as measured by a visual analogue scale was also comparable between the two groups. This is the first study to demonstrate that 6-n-propylthiouracil nontasters have taste sensitivity for the four basic tastes similar to that in 6-n-propylthiouracil tasters, at least in female adolescents, as measured by the gustatory test using a filter-paper disc method.

Salivary proteome and glucose levels are related with sweet taste sensitivity in young adults.

Abstract: Sweet taste plays a critical role in determining food preferences and choices. Similar to what happens for other oral sensations, individuals differ in their sensitivity for sweet taste and these inter-individual differences may be responsible for variations in food acceptance. Despite evidence that saliva plays a role in taste perception, this fluid has been mainly studied in the context of bitterness or astringency. We investigated the possible relationship between sweet taste sensitivity and salivary composition in subjects with different sucrose detection thresholds. Saliva collected from 159 young adults was evaluated for pH, total protein concentration and glucose. One- and bi-dimensional electrophoresis (2-DE) were performed and protein profiles compared between sweet sensitivity groups, with proteins that were differently expressed being identified by MALDI-FTICR-MS. Moreover, Western blotting was performed for salivary carbonic anhydrase VI (CA-VI) and cystatins and salivary amylase enzymatic activity was assessed in order to compare groups. Females with low sensitivity to sweet taste had higher salivary concentrations of glucose compared to those with sensitivity. For protein profiles, some differences were sex-dependent, with higher levels of α-amylase and CA-VI in low-sensitivity individuals and higher levels of cystatins in sensitive ones for both sexes. Body mass index was not observed to affect the association between salivary proteome and taste sensitivity. To our knowledge, these are the first data showing an association between sweet taste and saliva proteome.