The Obese Taste Bud Study

• Conditions: Obesity
• Interventions: Procedure: taste bud biopsy; Diagnostic Test: oral glucose tolerance test; Diagnostic Test: Taste sensitivity; Diagnostic Test: olfactory function; Diagnostic Test: taste bud density; Diagnostic Test: anthropometry; Other: biospecimen collection; Other: questionnaires

• Registration Number: NCT04633109
• Lead Sponsor: University of Leipzig

Brief Summary

The sense of taste is essential for priming food preferences and is therefore important for caloric uptake and body weight regulation. Recent studies show that obesity is linked to changes in taste sensation but also to a loss of taste buds on the tongue. This study aims to evaluate underlying mechanisms within the taste buds to potentially influence the sense of taste on the level of these sensory cells and in order to develop new treatment strategies to fight obesity.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2020-11-06
• Study Start: 2020-11-09
• Study First Submitted QC: 2020-11-16
• Study First Posted: 2020-11-18
• Status Verified: 2021-01
• Last Update Submitted: 2021-01-13
• Last Update Posted: 2021-01-14
• Primary Completion: 2022-07-15
• Study Completion: 2022-07-30

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 210

Inclusion Criteria

• normal weight (BMI 18.5-24.9)
• obesity (BMI >=30)
• overall healthy (no severe sickness, no cancer)
• written informed consent

Exclusion Criteria

• current pregnancy or currently breastfeeding
• cancer or tumors
• state after radiotherapy at head-neck area
• state after or current chemotherapy
• severe psychiatric-, cardiac-, kidney- or neurological illness
• diagnosed diabetes mellitus
• known dysfunction of smelling or tasting
• drug or alcohol abuse
• permanent medication with antidepressants, anticonvulsants, steroids and/or immunosuppressants

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
normal weight	olfactory function	Normal weight adults with BMI ranging from 18.5-24.9; men and women; age range 18-69years; written informed consent
normal weight	taste bud biopsy	Normal weight adults with BMI ranging from 18.5-24.9; men and women; age range 18-69years; written informed consent
normal weight	oral glucose tolerance test	Normal weight adults with BMI ranging from 18.5-24.9; men and women; age range 18-69years; written informed consent
normal weight	Taste sensitivity	Normal weight adults with BMI ranging from 18.5-24.9; men and women; age range 18-69years; written informed consent
normal weight	taste bud density	Normal weight adults with BMI ranging from 18.5-24.9; men and women; age range 18-69years; written informed consent
normal weight	anthropometry	Normal weight adults with BMI ranging from 18.5-24.9; men and women; age range 18-69years; written informed consent
normal weight	biospecimen collection	Normal weight adults with BMI ranging from 18.5-24.9; men and women; age range 18-69years; written informed consent
normal weight	questionnaires	Normal weight adults with BMI ranging from 18.5-24.9; men and women; age range 18-69years; written informed consent
obese	taste bud biopsy	Subjects with obesity as defined by BMI \>= 30; men and women; age range 18-69 years; written informed consent
obese	Taste sensitivity	Subjects with obesity as defined by BMI \>= 30; men and women; age range 18-69 years; written informed consent
obese	questionnaires	Subjects with obesity as defined by BMI \>= 30; men and women; age range 18-69 years; written informed consent
obese	oral glucose tolerance test	Subjects with obesity as defined by BMI \>= 30; men and women; age range 18-69 years; written informed consent
obese	olfactory function	Subjects with obesity as defined by BMI \>= 30; men and women; age range 18-69 years; written informed consent
obese	biospecimen collection	Subjects with obesity as defined by BMI \>= 30; men and women; age range 18-69 years; written informed consent
obese	taste bud density	Subjects with obesity as defined by BMI \>= 30; men and women; age range 18-69 years; written informed consent
obese	anthropometry	Subjects with obesity as defined by BMI \>= 30; men and women; age range 18-69 years; written informed consent

Primary Outcome Measures

Name	Time	Method
Identification of differential gene and protein regulation in isolated human taste cells between lean and obese subjects	through study completion, an average of 2 years	Transcriptomics (RNAsequencing (seq), single cell seq) and epigenomics (open chromatin mapping (ATACseq), Infinium MethylationEPIC Array) will be performed in isolated papillae fungiformes. Validation analyses by in vitro primary cell cultures of taste cell biopsy
Identification of correlations between taste cell biology with parameters of intervention	1 year	corrleation analyses will include factors of eating behavior, food preferences, life style factors, data from taste and smell screenings, anthropometric data, blood and saliva parameters

Secondary Outcome Measures

Name	Time	Method
Differences of salivary and tongue microbiome on taste cells in obesity in contrast to lean	2 years	whole mouth saliva as well as local tongue microbiome diversity will be analysed by 16S ribosomal RNA seq and related to further parameters of this study.
extracellular vesicle analyses of saliva in lean and obese subjects	2 years	The content of extracellular vesicles from saliva samples will be analysed and compared between the study groups as well as related to other parameters of this study.

Trial Locations

Locations (1)

Medical Clinic III, Division of Endocrinology, University Clinic of Leipzig; 🇩🇪 Leipzig, Saxony, Germany