fMRI of Hypothalamic Responses to Glucose, Fructose, Sucrose and Sucralose

Study Overview
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Brief Summary
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The study will consist of five occasions with one week in between. BOLD signal intensity of the hypothalamus will be measured using fMRI. Measurements will be done before and after drinking 300 ml plain water (reference) or water to which different sweeteners will be added.

Detailed Description
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The hypothalamus is known to be important for control of feeding behaviour as well as the regulation of temperature. Functional magnetic resonance imaging (fMRI) is a non-invasive method, which detects transient haemodynamic changes in the brain, using blood oxygen level dependent (BOLD) signal differences. In order to investigate the role of hypothalamic neural activity in response to different sweeteners, fMRI will be performed before, during and after ingestion of 300 ml plain water or 300 ml water containing 50 g glucose, 50 g fructose, 50 g sucrose or 0.33 g sucralose (high intensity sweetener not providing energy). All beverages will be consumed at 22 °C. The study uses a randomized cross-over design in 16 healthy male subjects with a normal body weight. There will be an interval of at least one week between the five occasions. Blood Oxygen Level Dependent signal intensity of the hypothalamus will be continuously measured for 21 minutes (5 minutes baseline, 4 minutes during drinking and 12 minutes after drinking).

Official Title
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Functional Magnetic Resonance Imaging of Human Hypothalamic Responses to Glucose, Fructose, Sucrose and Sucralose

Conditions
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Healthy

Intervention / Treatment
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* Other: Water
* Other: Glucose
* Other: Fructose
* Other: Sucrose
* Other: Sucralose


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Signed informed consent Age between 18 and 25 years BMI between 20 and 24 kg/m2 Length between 170 and 190 centimetres Exclusion Criteria: Diabetes or history of other disturbances of glucose metabolism (eg impaired glucose tolerance, hypoglycaemia). Any genetic or psychiatric disease (e.g. fragile X syndrome, major depression) affecting brain Any significant chronic disease Renal or hepatic disease Recent weight changes or attempts to lose weight (> 3 kg weight gain or loss, within the last 3 months) Smoking (current or last 6 months) Alcohol consumption of more than 21 units per week or use of recreational drugs at present or in the last year Recent blood donation (within the last 2 months) Recent participation in other biomedical research projects (within the last 3 months), participation in 3 or more biomedical research projects in one year Contra-indication to MRI scanning: Claustrophobia Pacemakers and defibrillators Nerve stimulators Intracranial clips Intraorbital or intraocular metallic fragments Cochlear implants Ferromagnetic implants

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 25 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Water-glucose-sucralose-fructose-sucrose<br>First plain water, then glucose, then sucralose, then fructose and then sucrose | Other: Water<br>* Water, 300 ml at room temperature<br>Other: Glucose<br>* Glucose, 50 grams in 300 ml water at room temperature<br>Other: Fructose<br>* Fructose, 50 grams in 300 ml water at room temperature<br>Other: Sucrose<br>* Sucrose, 50 grams in 300 ml water at room temperature<br>Other: Sucralose<br>* Sucralose, 0.33 grams in 300 ml water at room temperature<br>|
| Experimental: water-sucralose-glucose-sucrose-fructose<br>First plain water, then sucralose, then glucose, then sucrose and then fructose | Other: Water<br>* Water, 300 ml at room temperature<br>Other: Glucose<br>* Glucose, 50 grams in 300 ml water at room temperature<br>Other: Fructose<br>* Fructose, 50 grams in 300 ml water at room temperature<br>Other: Sucrose<br>* Sucrose, 50 grams in 300 ml water at room temperature<br>Other: Sucralose<br>* Sucralose, 0.33 grams in 300 ml water at room temperature<br>|
| Experimental: Glucose-water-fructose-sucralose-sucrose<br>First glucose, then plain water, then fructose, then sucralose and then sucrose | Other: Water<br>* Water, 300 ml at room temperature<br>Other: Glucose<br>* Glucose, 50 grams in 300 ml water at room temperature<br>Other: Fructose<br>* Fructose, 50 grams in 300 ml water at room temperature<br>Other: Sucrose<br>* Sucrose, 50 grams in 300 ml water at room temperature<br>Other: Sucralose<br>* Sucralose, 0.33 grams in 300 ml water at room temperature<br>|
| Experimental: Glucose-fructose-water-sucrose-sucralose<br>First glucose, then fructose, then plain water, then sucrose and then sucralose | Other: Water<br>* Water, 300 ml at room temperature<br>Other: Glucose<br>* Glucose, 50 grams in 300 ml water at room temperature<br>Other: Fructose<br>* Fructose, 50 grams in 300 ml water at room temperature<br>Other: Sucrose<br>* Sucrose, 50 grams in 300 ml water at room temperature<br>Other: Sucralose<br>* Sucralose, 0.33 grams in 300 ml water at room temperature<br>|
| Experimental: Fructose-glucose-sucrose-water-sucralose<br>First fructose, then glucose, then sucrose, then plain water and then sucralose | Other: Water<br>* Water, 300 ml at room temperature<br>Other: Glucose<br>* Glucose, 50 grams in 300 ml water at room temperature<br>Other: Fructose<br>* Fructose, 50 grams in 300 ml water at room temperature<br>Other: Sucrose<br>* Sucrose, 50 grams in 300 ml water at room temperature<br>Other: Sucralose<br>* Sucralose, 0.33 grams in 300 ml water at room temperature<br>|
| Experimental: Fructose-sucrose-glucose-sucralose-water<br>First fructose, then sucrose, then glucose, then sucralose and then plain water | Other: Water<br>* Water, 300 ml at room temperature<br>Other: Glucose<br>* Glucose, 50 grams in 300 ml water at room temperature<br>Other: Fructose<br>* Fructose, 50 grams in 300 ml water at room temperature<br>Other: Sucrose<br>* Sucrose, 50 grams in 300 ml water at room temperature<br>Other: Sucralose<br>* Sucralose, 0.33 grams in 300 ml water at room temperature<br>|
| Experimental: Sucrose-fructose-sucralose-glucose-water<br>First sucrose, then fructose, then sucralose, then glucose and then plain water | Other: Water<br>* Water, 300 ml at room temperature<br>Other: Glucose<br>* Glucose, 50 grams in 300 ml water at room temperature<br>Other: Fructose<br>* Fructose, 50 grams in 300 ml water at room temperature<br>Other: Sucrose<br>* Sucrose, 50 grams in 300 ml water at room temperature<br>Other: Sucralose<br>* Sucralose, 0.33 grams in 300 ml water at room temperature<br>|
| Experimental: Sucrose-sucralose-fructose-water-glucose<br>First sucrose, then sucralose, then fructose, then plain water and then glucose | Other: Water<br>* Water, 300 ml at room temperature<br>Other: Glucose<br>* Glucose, 50 grams in 300 ml water at room temperature<br>Other: Fructose<br>* Fructose, 50 grams in 300 ml water at room temperature<br>Other: Sucrose<br>* Sucrose, 50 grams in 300 ml water at room temperature<br>Other: Sucralose<br>* Sucralose, 0.33 grams in 300 ml water at room temperature<br>|
| Experimental: Sucralose-water-sucrose-glucose-fructose<br>First sucralose, then plain water, then sucrose, then glucose and then fructose | Other: Water<br>* Water, 300 ml at room temperature<br>Other: Glucose<br>* Glucose, 50 grams in 300 ml water at room temperature<br>Other: Fructose<br>* Fructose, 50 grams in 300 ml water at room temperature<br>Other: Sucrose<br>* Sucrose, 50 grams in 300 ml water at room temperature<br>Other: Sucralose<br>* Sucralose, 0.33 grams in 300 ml water at room temperature<br>|
| Experimental: Sucralose-sucrose-water-fructose-glucose<br>First sucralose, then sucrose, then plain water, then fructose and then glucose | Other: Water<br>* Water, 300 ml at room temperature<br>Other: Glucose<br>* Glucose, 50 grams in 300 ml water at room temperature<br>Other: Fructose<br>* Fructose, 50 grams in 300 ml water at room temperature<br>Other: Sucrose<br>* Sucrose, 50 grams in 300 ml water at room temperature<br>Other: Sucralose<br>* Sucralose, 0.33 grams in 300 ml water at room temperature<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Hypothalamic function in response to glucose, fructose, sucrose, and sucralose | fMRI will be performed before and after ingestion | Change from baseline (measured during 5 minutes before start of dinking) to post consumption (measured during 12 minutes after drinking). Drinking took 4 minutes. |