Astringency and Oral Health

Astringency Perception and Oral Health

The perception of astringency is thought to involve the interaction between tannins and salivary proteins. However, the mechanisms underlying this interaction are poorly understood. The tannins' subclass known as type A proanthocyanidins seems to have a positive effect on human health. Despite that, humans show large individual differences in the sensory perception and acceptance of astringent foods such as tea, wine and chocolate suggesting that this variation may have a genetic basis. Salivary proteins play an essential role both in affecting oral taste perception and in maintaining a healthy oral environment. Diverse microorganisms inhabit the oral cavity. The interactions between oral microbiota, host and environmental factors influence microbial homeostasis and ultimately human oral health. Understanding individual differences in salivary proteins, oral microbiome and the mechanisms by which tannins evoke the perception of astringency could provide important insights into the role of these compounds in human nutrition and health.

Study Overview

• Status: Completed
• Conditions: Taste, Altered; Saliva Altered
• Intervention / Treatment: Other: CPE; Other: Plain water

Detailed Description

This study examines the effects of a daily Cranberry Polyphenol Extract (CPE) oral rinse on salivary protein responses and the oral microbiome (as a proxy measure of oral health). The study will be conducted in healthy adults who are presumably at high-risk or low-risk of oral disease. High risk individuals include non-tasters of PROP (6-n-propylthiouracil) and homozygous recessive for TAS2R38 (Taste 2 Receptor Member 38) gene, while low-risk individuals include super-tasters of PROP and homozygous dominant for TAS2R38 gene.

The specific aims are to determine if the use of cranberry polyphenol extract rinse will:

1. alter the oral microbial profile
2. induce changes in the salivary protein response
3. be associated with changes in taste and flavor perception

Participants will be screened for good overall and oral health. Each subject's period of participation will be 2 weeks. Days 1-3 of the study is a run-in period. Subjects will rinse with spring water 2-times/day (after brushing their teeth in the morning and evening). During days 4-14, subjects will rinse in a similar manner with a solution of CPE in spring water. Saliva will be collected from subjects in a brief session (10 min) on day 1, day 3, and day 14. Saliva samples will be analyzed for gene, salivary proteins and microbial profile analysis. The purpose of this analysis is to measure the relative ratios of beneficial vs. disease-causing microbes in the mouth using microbial whole-genome sequencing (WGS). On each of the testing days, subjects will also evaluate food samples for standard taste and flavor attributes.

• Study Type: Interventional
• Enrollment (Actual): 49
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • New Jersey
    • New Brunswick, New Jersey, United States, 08901
      • Rutgers University, Department of Food Science

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• PROP insensitive individuals (PROP non-tasters; homozygous recessive for TAS2R38 gene)
• PROP high-sensitive individuals (PROP super-tasters; homozygous dominant for TAS2R38 gene)
• Overall healthy; good oral health and hygiene routine
• Current on a routine checkup by a oral/dental health professional
• Recently underwent dental/cleaning by a oral/dental health professional
• No ongoing oral health problems
• Agree to use intervention material as prescribed
• Agree to refrain from using any other oral rinse material during the term of the study

Exclusion Criteria:

• PROP medium-taster individuals (heterozygous for TAS2R38 gene)
• Taste or smell dysfunction
• Pregnant or nursing
• Oral piercings
• Smoking
• Use of medications other than birth control

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: PROP non-taster subjects; This arm will comprise of PROP non-taster subjects. Subjects will use a cranberry-derived oral rinse twice a day for 11 days following a 3-day plain water-rinse period.	Other: CPE; Subjects will use a cranberry-derived oral rinse twice a day for 11 days.; Other: Plain water; Subjects will use plain water as an oral rinse twice a day for 3 days.
Experimental: PROP super-taster subjects; This arm will comprise of PROP super-taster subjects. Subjects will use a cranberry-derived oral rinse twice a day for 11 days following a 3-day plain water-rinse period.	Other: CPE; Subjects will use a cranberry-derived oral rinse twice a day for 11 days.; Other: Plain water; Subjects will use plain water as an oral rinse twice a day for 3 days.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from Baseline Taste and Flavor Intensity Ratings after 11 days	Taste and flavor intensity ratings of cranberry juice and aronia juice samples will be collected 3 days after control intervention and then at the end of the experimental intervention. An end-anchored (None, Very Strong) 15 cm line scale will be used with taste and key flavor attributes.	Baseline measure 3 days after control intervention; Post intervention measure 11 days after experimental intervention
Change from Baseline Levels of Salivary Proteins after 11 days	Saliva will be collected 3 days after control intervention and then at the end of the experimental intervention. Samples will be analyzed via dot blot analysis and LC-MS (liquid chromatography-mass spectrometry) to establish proteomic composition before and after the intervention. Specifically, area of the ion current peaks (XIC peaks) generated will be used as a relative quantity of the salivary protein levels. The XIC peaks are proportional to the concentration of salivary proteins under constant conditions and will be used to understand the effect of the intervention on salivary protein levels.	Baseline measure 3 days after control intervention; Post intervention measure 11 days after experimental intervention
Change from Baseline Composition of Oral Microbiome after 11 days	Salivary samples will be collected 3 days after control intervention and then at the end of the experimental intervention. Samples will be analyzed for microbial composition via Whole Genome Sequencing and data used to understand changes in microbial diversity before and after the intervention. Specifically operational taxonomic units will be identified and classified at the species level.	Baseline measure 3 days after control intervention; Post intervention measure 11 days after experimental intervention

Collaborators and Investigators

• Sponsor: Rutgers, The State University of New Jersey
• Investigators: Principal Investigator: Beverly J Tepper, Ph.D., Rutgers University

Study record dates

Study Major Dates

• Study Start (Actual): November 1, 2022
• Primary Completion (Actual): November 14, 2023
• Study Completion (Actual): November 14, 2023

Study Registration Dates

• First Submitted: October 28, 2022
• First Submitted That Met QC Criteria: April 5, 2023
• First Posted (Actual): April 19, 2023

Study Record Updates

• Last Update Posted (Actual): March 28, 2025
• Last Update Submitted That Met QC Criteria: March 27, 2025
• Last Verified: March 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Sensation Disorders; Taste Disorders; Dysgeusia
• Other Study ID Numbers: Pro2022000271

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Individual participant data that underlie the results reported in this article after de-identification.
• IPD Sharing Time Frame: Beginning three months and ending 5 years after publication.
• IPD Sharing Access Criteria: Anyone who wishes to access the data. For any purpose.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No