The Obese Taste Bud Study

Obesity Clinical Trial

— OTB  

Official title:

The Obese Taste Bud Study

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT04633109
• Other study ID #: OTB-2020
• Secondary ID: DRKS00022950
• Status: Recruiting
• Start date: November 9, 2020
• Est. completion date: July 30, 2022

Study information

• Verified date: January 2021
• Source: University of Leipzig
• Contact: Imke Schamarek, Dr.
• Phone: +493419713803
• Email: Imke.Schamarek[@]medizin.uni-leipzig.de
• Is FDA regulated: No
• Study type: Observational

Clinical Trial 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.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 210
• Est. completion date: July 30, 2022
• Est. primary completion date: July 15, 2022
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 69 Years

Eligibility

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

Related Conditions & MeSH terms

• Obesity

Intervention

Procedure:
• taste bud biopsy
Taste buds will be surgically removed a) during a planned and medically induced elective surgery under full anesthesia; b) by local anesthesia in subjects without a medically induced surgery

Diagnostic Test:
• oral glucose tolerance test
75g glucose will be applied in drinking water following blood sample collection to evaluate glucose, insulin and C-peptide level.
• Taste sensitivity
Subjects are given taste strips with 4 concentrations per each taste quality of sweet, sour, salty, bitter and umami in a pseudo-randomized manner. Subjects are asked to identify the taste quality, state the intensity, preference and certainty.
• olfactory function
Subjects will be presented 16 different sniffing sticks in a randomized order, each for about 4seconds. People are then asked to identify the smell by choosing one out of 4 options (forced choice).
• taste bud density
The number of taste buds on the anterior tongue will be determined by colouring the tongue surface with food colour. Taste buds will apply more reddish as compared to non-taste tissue. Based on a digital photography the number of taste buds per subjects is counted manually.
• anthropometry
Anthropometric data collection will include measures of body height, body weight, arm-, upper- and lower leg circumferences, waist- and hip circumferences and a bioimpedance analysis to obtain data about body composition.

Other:
• biospecimen collection
Blood and saliva samples will be taken as well as a tongue swab.
• questionnaires
Through the use of several questionnaires, data about eating behavior, food preferences, life style factors and other will be obtained.

Locations

Country	Name	City	State
Germany	Medical Clinic III, Division of Endocrinology, University Clinic of Leipzig	Leipzig	Saxony

Sponsors (5)

Lead Sponsor	Collaborator
University of Leipzig	Helmholtz Institut für Metabolismus-, Adipositas- und Gefäßforschung, Klinik und Poliklinik für Hals-, Nasen- und Ohrenheilkunde, Klinik und Poliklinik für Mund-, Kiefer- und Plastische Gesichtschirurgie, Poliklinik für Zahnärztliche Prothetik und Werkstoffkunde

Country where clinical trial is conducted

Germany, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Identification of differential gene and protein regulation in isolated human taste cells between lean and obese subjects	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	through study completion, an average of 2 years
Primary	Identification of correlations between taste cell biology with parameters of intervention	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	1 year
Secondary	Differences of salivary and tongue microbiome on taste cells in obesity in contrast to lean	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.	2 years
Secondary	extracellular vesicle analyses of saliva in lean and obese subjects	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.	2 years