A Study of the Function of Hormones Present In Taste Buds

Completed

• Conditions: Diabetes; Obesity; Pre-Diabetes; Metabolic Syndrome

• Registration Number: NCT00233298
• Lead Sponsor: National Institute on Aging (NIA)

Brief Summary

The purpose of this study is to find out whether the hormones in the taste buds are affected by tasting and eating food, and also whether these hormone levels are affected by an increase in body weight or type 2 diabetes.

Detailed Description

Cephalic phase of insulin secretion is regulated by autonomic and endocrine responses to food-related sensory stimulation such as sight, smell, and taste. Human taste perception comprises of at least five distinct qualities: bitterness, saltiness, sourness, sweetness, and umami, the sensation elicited by glutamate, commonly found in protein (meat, fish, and legumes) and flavor enhancer such as monosodium glutamate (MSG).

Both the sweet and umami taste stimuli had been shown to illicit cephalic-phase insulin release in rats. Oral sensory stimulation in human with modified sham feeding (MSF where food is smelled, chewed, but not swallowed) had been shown to enhance insulin release during the cephalic phase, lower postprandial glucose level, and improve glucose tolerance in healthy subjects. The loss of pre-absorptive insulin response has been shown to impair glucose tolerance. Furthermore, patients with type 2 diabetes and their first degree relatives had been shown to have impairment of sweet taste.

Recently, glucagon-like peptide-1 (GLP-1) and peptide YY (PYY) have been found in the taste cells located in the taste buds of mice (unpublished data). These new findings raise several interesting questions of whether strict tasting of food without ingestion may stimulate secretion of GLP-1 and PYY from the taste cells, whether their secretion is involved in the afferent input of the cranial nerves, and whether this secretion is impaired in obesity and in patients with pre-diabetes or type 2 diabetes. We also want to investigate whether different tastants, such as sweet versus umami, and different food contents such as percent fat versus carbohydrate compositions, would elicit different hormonal responses.

Study Timeline

• Study Start: 2005-05-26
• Study First Submitted: 2005-10-03
• Study First Submitted QC: 2005-10-03
• Study First Posted: 2005-10-05
• Status Verified: 2015-01-02
• Study Completion: 2015-01-02
• Last Update Submitted: 2018-04-04
• Last Update Posted: 2018-04-05

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 225

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Whether CLP-1 and PYY are involved in the cephalic phase response during feeding	12 months
Differences in response among healthy, healthy obese, pre-diabetic or 3 diabetes	12 months

Trial Locations

Locations (1)

National Institute of Aging, Clinical Research Unit; 🇺🇸 Baltimore, Maryland, United States