Shivering and Glucose Homeostasis
Study Details
Study Description
Brief Summary
The purpose of this study is to investigate the effect of prolonged shivering thermogenesis on glucose homeostasis in overweight/obese humans.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
N/A |
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Experimental: Cold acclimation arm An oral glucose tolerance test will be performed on day 1 of the study. The next day (day 2), subjects will be exposed to shivering thermogenesis for at least 1 hour. The day after, an oral glucose tolerance test will be performed (day 3). The following 9 days, subjects will be exposed daily to shivering thermogenesis for at least 1 hour (day 4-12). On the last day (day 13), an oral glucose tolerance test will be performed. |
Other: Cold exposure
Subjects will be exposed to shivering thermogenesis for at least 1 hour for 10 days
|
Outcome Measures
Primary Outcome Measures
- area under the curve (AUC) of the glucose tolerance test [1 day following cold exposure and following 9 consecutive days of cold exposure]
area under the curve (AUC) of the glucose tolerance test before cold exposure, 1 day after cold exposure and after 9 consecutive days of cold exposure.
Secondary Outcome Measures
- skeletal muscle GLUT4 translocation [1 day following cold exposure and following 9 consecutive days of cold exposure]
Comparison between skeletal muscle GLUT4 translocation, as assessed by wide-field microscopy both before and after cold acclimation
Other Outcome Measures
- Insulin sensitivity [1 day following cold exposure and following 9 consecutive days of cold exposure]
Comparison between insulin sensitivity as estimated from the insulin and glucose concentrations during the OGTT both before and after cold acclimation.
- Heart rate [1 day following cold exposure and following 9 consecutive days of cold exposure]
Comparison between heart rate during cold exposure both before and after cold acclimation
- Blood pressure [1 day following cold exposure and following 9 consecutive days of cold exposure]
Comparison between blood pressure during cold exposure both before and after cold acclimation
- Energy expenditure [1 day following cold exposure and following 9 consecutive days of cold exposure]
Comparison between energy expenditure as assessed by indirect calorimetry both before and after cold acclimation
- Substrate oxidation [1 day following cold exposure and following 9 consecutive days of cold exposure]
Comparison between substrate oxidation as assessed by indirect calorimetry both before and after cold acclimation
- Plasma substrates [1 day following cold exposure and following 9 consecutive days of cold exposure]
Comparison between plasma substrates change during cold acclimation (including insulin, FFA, glucose) both before and after cold acclimation
- Plasma hormones [1 day following cold exposure and following 9 consecutive days of cold exposure]
Comparison between plasma hormones change during cold acclimation (including insulin, FFA, glucose) both before and after cold acclimation
- Skeletal muscle intramyocellular substrate content [1 day following cold exposure and following 9 consecutive days of cold exposure]
Comparison between skeletal muscle intramyocellular substrate content both before and after cold acclimation
- Protein expression in skeletal muscle [1 day following cold exposure and following 9 consecutive days of cold exposure]
Comparison between protein expression in skeletal muscle both before and after cold acclimation of specific pathways as determined by western blot
- Gene expression in skeletal muscle [1 day following cold exposure and following 9 consecutive days of cold exposure]
Comparison between gene expression in skeletal muscle both before and after cold acclimation of specific pathways as determined by RT-qPCR
- Body temperatures [1 day following cold exposure and following 9 consecutive days of cold exposure]
Change in both skin and core temperature upon cold acclimation as assessed by means of temperatures sensors and a core temperature pill
- Shivering activity [1 day following cold exposure and following 9 consecutive days of cold exposure]
Muscle shivering activity as determined by EMG. Comparison between shivering activity before and after cold acclimation
Eligibility Criteria
Criteria
Inclusion Criteria:
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Signed informed consent
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Caucasian
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Healthy (as determined by dependent physician based on medical questionnaire)
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Man, or postmenopausal (defined as at least 1year post cessation of menses) woman
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Aged 40 - 75 years at the start of the study
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BMI 27 and 35 kg/m2
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Stable dietary habits (no weight loss or gain >3kg in the past 3 months)
Exclusion Criteria:
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- Not meeting all inclusion criteria
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Medication use known to hamper subject's safety during study procedures
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Co-morbidities to which the intervention or program that may pose as a complicating factor
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Subjects diagnosed with cardiovascular diseases or cancer
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Fasting plasma glucose ≥ 7.0 mmol/l
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Haemoglobin < 7.8 mmol/l for women, or < 8.4 mmol/l for men
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Previously diagnosed with type 2 diabetes
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Abuse alcohol/drug abuse
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Subjects who do not want to be informed about unexpected medical findings during the screening/study or do not wish that their physician is informed.
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Engagement in structured exercise > 2h per week
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Participation in another biomedical study within 1 month before the first study
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Smoking
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Cold-acclimated, such as takes daily extended cold baths, works in a refrigerated environment, or regular cold-water swimming within 1 month of starting the study
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Maastricht University | Maastricht | Limburg | Netherlands | 6229ER |
Sponsors and Collaborators
- Maastricht University
Investigators
- Principal Investigator: Wouter van Marken Lichtenbelt, Prof., Maastricht University
Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- NL73487.068.20