Salivary Interactions With Chemosensations

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

TERMINATED

Clinical Phase

NA

Total Enrollment

32 participants

Study Classification

INTERVENTIONAL

Study Start Date

2019-01-05

Study Completion Date

2021-12-01

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

A counterbalanced, crossover design will be used to evaluate whether exposure to flavors vs. a control over time alters the perception of the flavor by changing an individual's salivary protein profile. Participants will complete 3 acute tasting protocols (baseline, after intervention 1, after intervention 2). The interventions will be with the flavor (epigallocatechin gallate, linolenic acid, capsaicin) or a control, in counterbalanced order, and will involve swishing and swallowing a solution of that sample 5 times per day for two weeks. Each of these flavors will be a separate sub-study.

Related Clinical Trials

Explore similar clinical trials based on study characteristics and research focus.

Interaction of Salivary Proteins and Polyphenols

NCT03501238

Diet Habit Diet Modification Taste, Altered +1 more

COMPLETED NA

Taste Perception, Salivary Proteins & the Oral Microbiome

NCT04107688

Saliva Altered Taste, Altered

COMPLETED NA

Effect of Flavored, Carbonated Drinks on Salivary Flow, Salivary Composition, and Taste Perceptions

NCT06933290

Taste Perception Saliva Production

RECRUITING NA

Salivary Proteome and Sensitivity to Bitterness

NCT01079338

Healthy

COMPLETED NA

Stimulation of Sensation and Improvement in Swallowing Using Oral Capsaicin

NCT01053286

Dysphagia Gastroesophageal Reflux

COMPLETED

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

This study is designed to test the relationship between salivary proteins, flavor sensation, and flavor exposure. For this study, we will test the bitterness/astringency of epigallocatechin gallate (EGCG, a polyphenol), the oleogustus (fatty acid taste) of linolenic acid, and the spiciness of capsaicin in conjunction with the concentration of specific salivary proteins (initially: salivary proline rich proteins for EGCG intervention, lipocalin-1 for the other two, but other proteins may be identified in the post-hoc analysis of the salivary proteome). We will test whether higher expression of these specific salivary proteins correlates with lower intensity of these flavors. We will further attempt to confirm the role of these salivary proteins using food-sourced functional analogs for these proteins. We would expect the food-sourced protein to have the same effect on flavor as the salivary protein if our hypotheses about salivary proteins' influence on flavor are correct. Finally, we will also use denatured versions of the food-sourced proteins to again confirm that effects are due to the function of these proteins binding the flavor.

Additionally, we will repeatedly expose individuals to the flavors by having them rinse and swallow solutions of the flavor compounds multiple times per day for two weeks. We will then re-evaluate the sensory ratings and salivary protein profiles. Two weeks of rinsing and swallowing a control solution will be used as a control during this intervention (for each of the flavors of interest).

To collect saliva and establish bitterness/astringency perception, we will use an acute tasting protocol. Participants will rinse with water, then taste and swallow, then taste and expectorate a solution of the flavor of interest. Saliva will be frozen for later proteomic analysis. Next participants will taste solutions of: flavor, flavor with food analog, the flavor with denatured food analog, water, water with the food analog, and water with denatured food analog. The participants will rank these solutions in order from least intense to most intense for the flavor quality of interest (bitterness/astringency for EGCG). After this, participants will taste all 6 samples again, and rate each individually for the intensity of the bitterness/astringency. After a short wait, this tasting and intensity rating will be repeated. All tastings will be done in counterbalanced order, and solutions will be labeled with randomized 3-digit codes.

This acute tasting protocol will be done: at baseline, after 2 weeks on one intervention (repeated tasting of flavor or control), after 2 weeks on the other intervention.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Diet, Food Choice, Taste

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Allocation Method

RANDOMIZED

Intervention Model

CROSSOVER

Primary Study Purpose

BASIC_SCIENCE

Blinding Strategy

SINGLE

Participants

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

Epigallocatechin gallate

Epigallocatechin gallate solutions will be provided to participants to rinse with daily for two weeks. A control solution will be provided for two weeks as well. Order will be counterbalanced across participants and groups.

Group Type EXPERIMENTAL

Epigallocatechin gallate

Intervention Type OTHER

Colored solution prepared with epigallocatechin gallate to be consumed daily for two weeks during the epigallocatechin gallate intervention.

Epigallocatechin gallate control

Intervention Type OTHER

Colored control solution to be consumed daily for two weeks during the epigallocatechin gallate intervention.

Linoleic acid

Linoleic acid emulsion will be provided to participants to rinse with daily for two weeks. A control solution will be provided for two weeks as well. Order will be counterbalanced across participants and groups.

Group Type EXPERIMENTAL

Linoleic acid

Intervention Type OTHER

Colored emulsion prepared with linoleic acid to be consumed daily for two weeks during the linoleic acid intervention.

Linoleic acid control

Intervention Type OTHER

Colored control solution to be consumed daily for two weeks during the linoleic acid intervention.

Capsaicin

Capsaicin solutions will be provided to participants to rinse with daily for two weeks. A control solution will be provided for two weeks as well. Order will be counterbalanced across participants and groups.

Group Type EXPERIMENTAL

Capsaicin solution

Intervention Type OTHER

Colored solution prepared with capsaicin to be consumed daily for two weeks during the capsaicin intervention.

Capsaicin control

Intervention Type OTHER

Colored control solution to be consumed daily for two weeks during the capsaicin intervention.

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

Epigallocatechin gallate

Colored solution prepared with epigallocatechin gallate to be consumed daily for two weeks during the epigallocatechin gallate intervention.

Intervention Type OTHER

Epigallocatechin gallate control

Colored control solution to be consumed daily for two weeks during the epigallocatechin gallate intervention.

Intervention Type OTHER

Linoleic acid

Colored emulsion prepared with linoleic acid to be consumed daily for two weeks during the linoleic acid intervention.

Intervention Type OTHER

Linoleic acid control

Colored control solution to be consumed daily for two weeks during the linoleic acid intervention.

Intervention Type OTHER

Capsaicin solution

Colored solution prepared with capsaicin to be consumed daily for two weeks during the capsaicin intervention.

Intervention Type OTHER

Capsaicin control

Colored control solution to be consumed daily for two weeks during the capsaicin intervention.

Intervention Type OTHER

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

* Agree to maintain current diet throughout intervention
* Agree to inform us if medication use changes during study.
* Willing and able to taste and consume samples, as well as take pictures to document use of the flavor during intervention.

Exclusion Criteria

* Known issues with salivation, taste, or smell
* Taking medications other than birth control
* User of tobacco products or electronic cigarettes within the last 30 days

Minimum Eligible Age

18 Years

Maximum Eligible Age

45 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

Yes