Obesity
Conditions
Keywords
D-limonene, lavender oil (SLVO), Olfactory stimulation, Obesity, glucose metabolism
Brief summary
In this preliminary short-term study it is investigated, whether a short olfactory stimulation with D-Limonene leads to an acute improvement of glucose metabolism in patients with obesity.
Interventions
OTHERD-Limonene
Patient will put the aspUraclip®, a commercially available mini-inhalator filled for our study purpose filled with 1% D-Limonene in the nose for 15 minutes
OTHERSLVO
Patient will put the aspUraclip®, a commercially available mini-inhalator filled for our study purpose filled with 1% SLVO in the nose for 15 minutes
Sponsors
University Hospital, Basel, Switzerland
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
OTHER
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
18 Years to 70 Years
Healthy volunteers
No
Inclusion criteria
* Age 18-70 years * Obesity (BMI ≥35 kg/m2) * Written informed consent * Normosmia (defined by sniffin Sticks test)
Exclusion criteria
* Known allergy to D-Limonene, citrus fruits, citrus flavours, SLVO * Regular smoking * Current illicit drug abuse including daily marijuana and cannabidiol (CBD) consumption (alcohol ≤2 drinks per day allowed) * Diabetes mellitus * Pre-Treatment with insulin sensitizing drugs including GLP-1 analogues * History of neurodegenerative diseases, severe head trauma * Severe renal impairment (e.g. estimated glomerular filtration rate \<30 ml/min/m2) * Known liver cirrhosis or other severe liver impairment * Acute upper respiratory tract infection * Uncontrolled dysthyroidism * Uncontrolled hypertension * Regular use of psychopharmaceutic drugs * Patient aims to start a new diet or exercise program during the study * Bariatric surgery * Pregnancy/Lactation * Symptoms of menopause * Inability to follow the procedures of the study, e.g. due to language problems, psychological disorders, dementia, etc. * Participation in an interventional study within the last 3 months
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change of area under blood glucose curve (AUBGC) | Time Frame: baseline blood exam (timepoint 0) and further blood collections: 5, 15, 30, 60, 90 and 120 minutes after drinking a standardized mixed-meal solution | area under the blood glucose curve (AUBGC) during a mixed-meal test after stimulation with D-Limonene compared to baseline |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| AUBGC | Time Frame: baseline blood exam (timepoint 0) and further blood collections: 5, 15, 30, 60, 90 and 120 minutes after drinking a standardized mixed-meal solution | AUBGC during a mixed-meal test after stimulation with SLVO compared to baseline |
| Visual Analogue Scale (VAS score) | Time Frame: baseline VAS score (timepoint 0) and VAS scores will be evaluated after 15, 30, 60, 90 and 120 minutes after drinking a standardized mixed-meal solution | VAS scores on hunger, appetite, nausea, mood, and hedonics of odour and/or taste of the mixed-meal shake, where 0 equals none, and 10 the maximum of each category |
| Change in plasma insulin levels | Time Frame: baseline blood exam (timepoint 0) and further blood collections: 5, 15, 30, 60, 90 and 120 minutes after drinking a standardized mixed-meal solution | Plasma insulin levels (mIU/L) |
| Change in plasma peak glucose levels | Time Frame: baseline blood exam (timepoint 0) and further blood collections: 5, 15, 30, 60, 90 and 120 minutes after drinking a standardized mixed-meal solution | Plasma peak glucose levels (mmol/L) |
| Change in plasma levels of glucagon-like peptide 1 (GLP-1) | Time Frame: baseline blood exam (timepoint 0) and further blood collections after 5, 15, 30, 60, 90 and 120 minutes after drinking a standardized mixed-meal solution | Plasma levels of GLP-1 (pmol/L) |
| Change in plasma levels of gastric inhibitory polypeptide (GIP) | Time Frame: baseline blood exam (timepoint 0) and further blood collections after 5, 15, 30, 60, 90 and 120 minutes after drinking a standardized mixed-meal solution | Plasma levels of GIP (pmol/L) |
| Change in plasma levels of Ghrelin | Time Frame: baseline blood exam (timepoint 0) and further blood collections after 5, 15, 30, 60, 90 and 120 minutes after drinking a standardized mixed-meal solution | Plasma levels of Ghrelin (pg/ml) |
| Change in plasma levels of Leptin | Time Frame: baseline blood exam (timepoint 0) and further blood collections after 5, 15, 30, 60, 90 and 120 minutes after drinking a standardized mixed-meal solution | Plasma levels of Leptin (ng/ml) |
| Change in plasma levels of Glucagon | Time Frame: baseline blood exam (timepoint 0) and further blood collections after 5, 15, 30, 60, 90 and 120 minutes after drinking a standardized mixed-meal solution | Plasma levels of Glucagon (pmol/L) |
| Change in plasma Levels of Interleukin-6 | Time Frame: baseline blood exam (timepoint 0) and further blood collections after 5, 15, 30, 60, 90 and 120 minutes after drinking a standardized mixed-meal solution | Plasma Levels of Interleukin-6 (pg/ml) |
| Change in plasma Levels of C-reactive protein | Time Frame: baseline blood exam (timepoint 0) and further blood collections after 5, 15, 30, 60, 90 and 120 minutes after drinking a standardized mixed-meal solution | Plasma Levels of C-reactive protein (μg/ml) |
| Change in plasma levels of lipids like LDL-cholesterine, total cholesterine, triglycerides | Time Frame: baseline blood exam (timepoint 0) and further blood collections: 5, 15, 30, 60, 90 and 120 minutes after drinking a standardized mixed-meal solution | Plasma levels of lipids (mmol/L) like LDL-cholesterine, total cholesterine, triglycerides |
| Change in heart rate | Blood pressure and heart rate will be measured at the following times: baseline (timepoint 0) and 30, 60, 120 minutes drinking a standardized mixed-meal solution | Heart rate (heart beats per minute) |
| Change in blood pressure | Blood pressure and heart rate will be measured at the following times: baseline (timepoint 0) and 30, 60, 120 minutes drinking a standardized mixed-meal solution | blood pressure (mm Hg) |
| Change in plasma levels of Peptide YY (PYY) | Time Frame: baseline blood exam (timepoint 0) and further blood collections after 5, 15, 30, 60, 90 and 120 minutes after drinking a standardized mixed-meal solution | Plasma levels of PYY (pg/ml) |
Countries
Switzerland
Outcome results
None listed