Bariatric Surgery, Obesity
Conditions
Keywords
fMRI, hormonal satiety signaling, hypothalamus, weight loss
Brief summary
The overall aim of the proposed project is to investigate the contribution of changes in neuronal food processing, hypothalamic reactivity and hormonal factors to weight loss after bariatric surgery.
Interventions
PROCEDUREbariatric surgery
bariatric surgery
DIETARY_SUPPLEMENTconservative diet
conservative diet
Sponsors
University of Heidelberg Medical Center
Study design
Observational model
CASE_CONTROL
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Inclusion criteria
* planning to undergo bariatric surgery * planning to take part in a conservative diet
Exclusion criteria
* inability to undergo fMRI * psychiatric disorders * metabolic disorders
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Functional magnetic resonance imaging following intravenous glucose infusion. | 2 weeks before surgery or start of dietary intervention and 2 weeks after surgery or start of dietary intervention. | Change in responsivity of the hypothalamus (extracted as percent signal change) as the core region of homeostatic control will be assessed after an intravenous glucose infusion (by calculating the area under the curve of hypothalamic responsivity) before and after bariatric surgery or dietary intervention. |
| Experimental functional magnetic resonance imaging task (gustatory stimulation). | 2 weeks before surgery or start of dietary intervention and 2 weeks after surgery or start of dietary intervention. | Neuronal gustatory processing of food stimuli will be assessed (ingestion of sweet liquids using a gustometer) using a general linear model (comparing brain activation during ingestion of sweet liquids with brain activation during the ingestion of water) and within as well as between groups analyses. Changes in neural gustatory processing of food stimuli will be assessed before and after bariatric surgery or dietary intervention. |
| Assessment of glucose-induced changes in peripheral ghrelin using blood samples. | 15 minutes before and 15 minutes after functional magnetic resonance imaging | Blood is collected to measure the concentration of peripheral ghrelin as an indicator of hormonal satiety signaling. Blood samples are collected at the beginning and end of each experimental session to assess the influence of intravenuous infusion of glucose on ghrelin signaling. Blood samples will be analysed using using commercially available kits (enzyme-linked immunosorbent assay). |
Other
| Measure | Time frame | Description |
|---|---|---|
| Weight change | 12 months | Change in weight following bariatric surgery or dietary intervention |
Countries
Germany
Contacts
Primary ContactJoe J Simon, PD
Outcome results
None listed