Fat Perception in Humans (09-0873) (OT)

The Washington University

Status: Completed

Conditions: Obesity

Study type: Observational

Funder types: Other; Industry

Identifiers

NCT01128400

09-0873

Details and patient eligibility

About

There are many substances naturally present in the mouth that may help us taste fat in food. Two of these substances (lipases and CD36) will be examined in this study.

The presence of fat in food increases food tastiness, therefore people often over-eat high-fat foods and gain weight. The purpose of this study is to determine if blocking lipases and some genetic variations in the CD36 gene will make fatty food less tasty so that people eat less. Our hypothesis is that Orlistat and a particular gene will increase one's ability to detect fat.

Full description

1. Determine the effect of lipolysis inhibition in oral cavity on orosensory detection of fat in humans.

   Hypothesis: Orally applied Orlistat will increase detection thresholds of TAGs but not FFA in humans.

   To test this hypothesis we will measure triolein (a TAG) and oleic acid (a FFA) taste detection thresholds with a three-alternative forced-choice (3-AFC) ascending concentration method under two conditions (Orlistat day vs. Control day). To control for olfactory input, subjects will be assessed wearing noseclips.

2. Determine the effect of CD36 variants on fat taste perception in humans. Hypothesis: SNPs that associate with reduced CD36 expression will be associated with higher FFA and TAG detection thresholds

To test this hypothesis we will measure triolein and oleic acid taste detection thresholds in subjects who carry of the common CD36 e-SNP rs1761667 (i.e. a SNP that significantly reduces CD36 level and has a minor allele frequency of 38-48%). We expect subjects who are at least heterozygous for the expression reducing allele to have higher triolein and oleic acid taste detection thresholds compared to non-carrier subjects.

Enrollment: 40 patients

Sex: All

Ages: 21 to 50 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Body Mass Index greater than 30 kg/m²

Exclusion criteria

• smokers or who quit smoking less than six months ago
• pregnancy
• breastfeeding
• diabetes
• taking medications that might affect taste perception
• previous malabsorptive or restrictive intestinal surgery

Trial design

40 participants in 3 patient groups

rs1761667- AA genotype

Description:

subjects carrying the CD36 genotype rs1761667, i.e. a Single Nucleotide Polymorphism that significantly reduces CD36 level and has a minor allele frequency of 38-48%.

rs1761667-GG genotype

Description:

subjects who are homozygous of CD36 genotype rs1761667-G allele.

rs1761667-AG genotype

Description:

Heterozygous of CD36 gene rs1761667-A genotype.