Sweet Taste Receptors and the Secretion of Glucagon-like Peptide-1 and Peptide YY

Study Overview
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Brief Summary
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The purpose of this study is to determine the functional significance of sweet taste receptors in the secretion of GI satiety peptides by using a specific sweet taste receptor antagonist to block sweet taste perception in the gut.

Detailed Description
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There is strong evidence that taste signaling mechanisms identified in the oral epithelium also operate in the gut. It is suggested that open-type enteroendocrine cells directly sense nutrient via alpha-gustducin coupled taste receptors to modulate the secretion of glucagon like peptide-1 (GLP-1) and peptide YY (PYY). Several nutrient responsive G-protein coupled receptors have been identified in the human gut, including the sweet taste responsive T1R2/T1R3 heterodimer, the amino acid/umami responsive T1R1/T1R3 as well as GPR120 for unsaturated long-chain free fatty acids.The functional significance of sweet taste receptors in glucose stimulated secretion of GLP-1 and PYY will be determined by intragastric infusion of 75 g glucose with different concentrations of lactisole (150 ppm, 300 ppm and 450 ppm)in a double blind, 4-way crossover trial including 16 healthy subjects.

Official Title
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The Functional Significance of Gut-expressed Taste Receptors in the Secretion of Glucagon-like Peptide-1 and Peptide YY

Conditions
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Appetite and General Nutritional Disorders, Hormone Replacement

Intervention / Treatment
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* Dietary Supplement: lactisole


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy subjects BMI of 19.0-24.5 Age 18-40 stable body weight for at least 3 month Exclusion Criteria: smoking substance abuse regular intake of medication medical or psychiatric illness gastrointestinal disorders or food allergies

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: 75 g glucose + 150 ppm lactisole<br> | Dietary Supplement: lactisole<br>* lactisole (flavoring agent/sweet taste antagonist) dissolved with 75 g glucose in 300 mL tap water; administered via intragastric tube<br>* Other names: water;|
| Active Comparator: 75 g glucose + 300 ppm lactisole<br> | Dietary Supplement: lactisole<br>* lactisole (flavoring agent/sweet taste antagonist) dissolved with 75 g glucose in 300 mL tap water; administered via intragastric tube<br>* Other names: water;|
| Active Comparator: 75 g glucose + 450 ppm lactisole<br> | Dietary Supplement: lactisole<br>* lactisole (flavoring agent/sweet taste antagonist) dissolved with 75 g glucose in 300 mL tap water; administered via intragastric tube<br>* Other names: water;|
| Placebo Comparator: 75 g glucose<br> | Dietary Supplement: lactisole<br>* lactisole (flavoring agent/sweet taste antagonist) dissolved with 75 g glucose in 300 mL tap water; administered via intragastric tube<br>* Other names: water;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Gastrointestinal peptide secretion |  | 2 hours blood sampling |