Insulin Sensitivity
Conditions
Keywords
insulin sensitivity, high-fat diet
Brief summary
The aim of the intervention is to gain insight into the long term effect of dietary fatty acid quality on insulin sensitivity and health parameters in healthy men. Whole body and peripheral insulin sensitivity were measured, together with analyses of plasma hormones and metabolites. The plasma proteome was also analyzed. Molecular adaptations in skeletal muscle and adipose tissue were subject for investigation. Furthermore, gut microbiota population number and diversity will be analyzed from faeces samples obtained before and after the intervention.
Detailed description
Two experimental diets with a high fat content (65 E% fat), enriched in either saturated or polyunsaturated fatty acids, were provided for 6 weeks to healthy men, in a randomized controlled intervention study with two arms. Healthy, untrained, non-obese male subjects (27-45 years) were included in the study. The experimental diets are eucaloric, and thus provided so the subjects remains weight stable. Before and after the intervention, two experimental days was conducted (2 experiments before and 2 experiments after the intervention). At pre-intervention, subjects completed a high-fat meal test and insulin sensitivity was measured by the hyperinsulinemic-euglycemic clamp. On both days, blood and tissue biopsies were obtained. These two experimental days were repeated at the end of the 6 weeks intervention. The hyperinsulinemic-euglycemic clamp was combined with stable isotope infusion (deuterium labelled glucose) in order to measure hepatic glucose production. Before the clamp, a catheter is inserted into the femoral vein, to enable measurement of insulin stimulated glucose uptake across the leg. Biopsies are obtained by the needle biopsy method from the vastus lateralis muscle and peri-umbilical subcutaneous adipose tissue. Blood samples were analyzed for glucose, insulin, inflammatory markers, gut hormones, adipokines, plasma fatty acid composition, and lipoprotein profile. Indirect calorimetric was also applied to measure substrate oxidation during the experimental days.
Interventions
BEHAVIORALHigh-fat diet
The aim of the intervention is to evaluate whether insulin sensitivity and selected Health parameters is affected, when the intake of saturated fatty acids or polyunsaturated fatty acids are highly increased, even when subjects are in energy balance.
Sponsors
University of Copenhagen
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
MALE
Age
27 Years to 45 Years
Healthy volunteers
Yes
Inclusion criteria
* healthy male subjects * 27-45 years * BMI 22-31 * maximal oxygen uptake \<48 ml/kg/min
Exclusion criteria
* smokers * use of medication * parents with type-2 diabetes
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in whole body and peripheral insulin sensitivity | Each subject completes a hyperinsulinemic-euglycemic clamp at pre-intervention (week 0) and again after 6 weeks of intervention. | This outcome will be evaluated with the hyperinsulinemic-euglycemic clamp, combined with the femoral arterio-venous balance technique |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in gut microbiota population number and diversity | Faeces samples are obtained from each subject at pre-intervention (week 0), and after the intervention (week 6). Analyses will be performed when the last faeces sample is obtained. | Gut microbiota will be analyzed in faeces samples obtained from the subjects before and after the intervention (using 18s-RNA sequencing) |
Other
| Measure | Time frame | Description |
|---|---|---|
| Change in molecular adaptations in skeletal muscle and adipose tissue induced by saturated and polyunsaturated fatty acids | Biopsies are obtained at pre-intervention (week 0) and at week 6 after the intervention. Analyses will be performed when the last tissue biopsies are obtained. | Skeletal muscle and subcutaneous adipose tissue biopsies are obtained from each subject. Specific molecular analyses (western blotting and real time-PCR) are applied to tissue samples to assess changes in relevant genes and proteins. |
Outcome results
None listed