Diabetes Mellitus
Conditions
Keywords
Smoking, Diabetes, Incretin hormones, Glucose tolerance
Brief summary
The study aims to evaluate the effect of smoking on postprandial responses such as plasma glucose, secretion of gut - and pancreatic hormones and gastric emptying in healthy, heavy smoking men.
Detailed description
Epidemiological studies show that active smoking increases the risk of type 2 diabetes in a dose-dependent fashion. Smokers seem to be characterized by central obesity, increased inflammatory markers and oxidative stress, which may lead to insulin resistance and irregularities in glucose metabolism. The current study is a meal test study, in which the aim is to examine a number of variables during a liquid mixed meal test (including gastric emptying, glucose tolerance, gut and pancreatic hormone responses, gall bladder emptying, appetite and food intake) performed in healthy non-smoking subjects and in healthy smokers with or without concomitant cigarette smoking. The investigators hypothesize that smoking-induced increases in circulating nicotine levels and simultaneous activation of nicotinic receptors in the gastrointestinal tract and in the autonomic nervous system would have detrimental effect on postprandial glucose metabolism and, thus, constitute an important link between smoking and the risk of type 2 diabetes. The current study will help to clarify this hypothesis and improve our general understanding of the association between smoking and gut hormone secretion, gastric emptying and glucose metabolism.
Interventions
DIETARY_SUPPLEMENTLiquid mixed meal
The subjects will ingest a 400 ml chocolate drink, rich on carbohydrates, fat and lipids. In the following 4 hours, blood samples will be drawn from a PVC for the measurement of plasma glucose, gut- and pancreatic hormones, acetaminophen etc. After the 4 hours, the subjects will be offered an ad libitum meal.
OTHERSkin Biopsy
All subjects will undergo a skin biopsy procedure. Two small (3 mm) biopsies will be taken from the hip area under local anaesthesia. Standard wound treatment will follow.
Sponsors
University of Copenhagen
European Foundation for the Study of Diabetes
University Hospital, Gentofte, Copenhagen
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
MALE
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* Both groups * Caucasian ethnicity * Healthy males * Normal haemoglobin * Age above 18 years * Informed and written consent * BMI \>20 kg/m2 Smokers • Minimum 20 cigarettes pr. day for at least 1 year Non-smokers • No smoking on a regular basis
Exclusion criteria
* Both groups * Diabetes or prediabetes (fasting plasma glucose levels \>6.5 mM or HbA1c \>6.0%) * First- or second-degree relatives with diabetes * Liver disease (alanine aminotransferase (ALAT) and/or serum aspartate aminotransferase (ASAT) \>2 times normal values) or history of hepatobiliary disorder * Gastrointestinal disease, previous intestinal resection, cholecystectomy or any major intra-abdominal surgery * Hypo- or hyperphosphataemia * Nephropathy (serum creatinine \>150 µM and/or albuminuria * Treatment with medicine that cannot be paused for 12 hours * Hypo- or hypercalcaemia * Hypo- and hyperthyroidism * Treatment with oral anticoagulants * Active or recent malignant disease * Any treatment or condition requiring acute or sub-acute medical or surgical intervention * Any condition considered incompatible with participation by the investigators
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Postprandial response of glucagon-like peptide-1 (GLP-1) | -30, -20, -10, 0, 10, 20, 30, 50, 70, 90, 120, 150, 180, 240 minutes (meal tests start at 0 min) | Incremental and total area under the Concentration-Time Curve (AUC 0-240 min) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Postprandial response of Glukagon | -30, -20, -10, 0, 10, 20, 30, 50, 70, 90, 120, 150, 180, 240 minutes (meal tests start at 0 min) | Incremental and total area under the Concentration-Time Curve (AUC 0-240 min) |
| Postprandial response of CCK | -30, -20, -10, 0, 10, 20, 30, 50, 70, 90, 120, 150, 180, 240 minutes (meal tests start at 0 min) | Incremental and total area under the Concentration-Time Curve (AUC 0-240 min) |
| Postprandial response of Gastrin | -30, -20, -10, 0, 10, 20, 30, 50, 70, 90, 120, 150, 180, 240 minutes (meal tests start at 0 min) | Incremental and total area under the Concentration-Time Curve (AUC 0-240 min) |
| Postprandial response of GIP | -30, -20, -10, 0, 10, 20, 30, 50, 70, 90, 120, 150, 180, 240 minutes (meal tests start at 0 min) | Incremental and total area under the Concentration-Time Curve (AUC 0-240 min) |
| Postprandial response of insulin | -30, -20, -10, 0, 10, 20, 30, 50, 70, 90, 120, 150, 180, 240 minutes (meal tests start at 0 min) | Incremental and total area under the Concentration-Time Curve (AUC 0-240 min) |
| Blood Inflammatory and metabolic markers (composite) | -30, -20, -10, 0, 10, 20, 30, 50, 70, 90, 120, 150, 180, 240 minutes (meal tests start at 0 min) | — |
| Gall bladder volume | -30, 20, 40, 80, 240 minutes (meal tests start at 0 min) | Assessment of gall bladder volume will be mediated by ultrasound |
| Gastric emptying | -30, -20, -10, 0, 10, 20, 30, 50, 70, 90, 120, 150, 180, 240 minutes (meal tests start at 0 min | Measurement of acetaminophen is taken as a measure of gastric emptying |
| GLP-1 receptor expression in the skin | After the 240 minutes | Analysis of the skin cells from the biopsies. |
| Postprandial increment in plasma glucose | -30, -20, -10, 0, 10, 20, 30, 50, 70, 90, 120, 150, 180, 240 minutes (meal tests start at 0 min) | Incremental and total area under the Concentration-Time Curve (AUC 0-240 min) |
Countries
Denmark
Outcome results
None listed