Obesity
Conditions
Keywords
Obesity, food preferences, taste disorder, taste bud, metabolic disease, feeding behavior
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.
Interventions
PROCEDUREtaste 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_TESToral glucose tolerance test
75g glucose will be applied in drinking water following blood sample collection to evaluate glucose, insulin and C-peptide level.
DIAGNOSTIC_TESTTaste 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.
DIAGNOSTIC_TESTolfactory 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).
DIAGNOSTIC_TESTtaste 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.
DIAGNOSTIC_TESTanthropometry
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.
OTHERbiospecimen collection
Blood and saliva samples will be taken as well as a tongue swab.
OTHERquestionnaires
Through the use of several questionnaires, data about eating behavior, food preferences, life style factors and other will be obtained.
Sponsors
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
University of Leipzig
Study design
Observational model
CASE_CONTROL
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to 69 Years
Healthy volunteers
Yes
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 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
| Measure | Time frame | Description |
|---|---|---|
| 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. |
Countries
Germany
Contacts
Primary ContactImke Schamarek, Dr.
Backup ContactKerstin Rohde-Zimmermann, Dr.
Outcome results
None listed