Prediabetes, Insulin Resistance
Conditions
Brief summary
The overall goal of this study is to investigate the effects and the mechanisms of action of a fish peptide and vitamin D on glucose metabolism, insulin secretion, and cardiometabolic risk profile in overweight men. Transcriptomic and metabolomic approaches will be used to study the acute physiological effects of fish nutrients and to discover gene/metabolite networks that underlie these effects.
Detailed description
Sedentary lifestyle and excess calorie intake have contributed to a dramatic increase in the occurrence of obesity, metabolic syndrome (MetS), type 2 diabetes (T2D) and cardiovascular disease (CVD) The first step in reducing the excessive CVD risk associated with the presence of the MetS is the adoption of a healthier lifestyle. A balanced diet, including high-nutritive and low-energy foods such as fish, is an important component of a healthy diet. Fish is a major source of n-3 PUFA, high-quality protein, and other essential nutrients such as vitamin D. Fish consumption may therefore improve the components of the MetS and reduce the incidence of T2D and CVD in obese subjects.The foundation of this project stems from the well-recognized fact that few Canadians meet the weekly dietary recommendation for fish consumption (i.e. 2 servings/week) and thus intakes of both n-3 polyunsaturated fatty acid (PUFA) and fish protein are low in the general population, and even lower in obese subjects. Since some people simply dislike fish and because certain types of fish contain toxic contaminants, including heavy metals and environmental pollutants, fish consumption remains low. Therefore, dietary choices limit intake of its key nutrients, thus increasing risk for MetS, T2D and CVD. Also, fish is one of the richest food sources of dietary vitamin D which may also contribute to the health benefits of fish consumption. Indeed, it is currently estimated that ∼40% of Canadians have low serum 25-hydroxyvitamin D \[25(OH)D\] concentrations (≤50 nM) and that ∼70% are below 75 nM. In addition, obesity is an important risk factor for low serum 25(OH)D.The main objective of this study is to investigate the acute effects and mechanisms of action of fish peptide and vitamin D on glucose metabolism, parameters of insulin sensibility and secretion, and cardiometabolic risk profile in overweight men. A four-arm randomized crossover design will be used to test the metabolic effects of consuming prior to a 3h-oral glucose tolerance test (OGTT), supplements containing either fish peptide (3 grams), vitamin D3 (1000 IU), a combination of fish peptide + vitamin D3 or a placebo.
Interventions
DIETARY_SUPPLEMENTFish peptide supplement
6 capsules of fish peptide supplement (3g/each) administered prior to one of the OGTT
DIETARY_SUPPLEMENTVitamin D supplement
1 tablet of vitamin D3 (1000 UI) administered prior to one of the OGTT
DIETARY_SUPPLEMENTFish peptide + Vitamin D3 supplements
6 capsules of fish peptide (3g/each) + 1 tablet of vitamin D3 (1000 UI) administered prior to one of the OGTT
DIETARY_SUPPLEMENTPlacebo
7 tablets of placebos administered prior to one the OGTT
Sponsors
Canadian Institutes of Health Research (CIHR)
Laval University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
PREVENTION
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
MALE
Age
18 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
* overweight (BMI 25-40 kg/m2) * fasting triglycerides ≥ 1.5 mmol/L * fasting insulin ≥ 60 pmol/L * non-smoking * stable weight in the past 3 months
Exclusion criteria
* diabetes * chronic diseases * taking drugs that could affect glucose or lipid metabolism * taking dietary supplements or natural health products * major surgery 3 months prior to the study * fish or seafood allergy * lactose intolerance
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Serum glucose area under the curve (Glucose AUC) | 0-180 min | The area under the curve for serum glucose concentration is calculated from 0-180min after 75g glucose is ingested |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Serum insulin area under the curve (Insulin AUC) | 0-180 min | Area under the curve for serum insulin |
| Serum C-peptide area under the curve (C-peptide AUC) | 0-180 min | Area under the curve for serum C-peptide |
| Serum triglycerides concentrations | -15, 0, 15, 30, 60, 120, 180 min post 75g glucose | changes in the triglycerides concentration at each time point of the OGTT |
| Serum 25(OH)D concentrations | 4 weeks | Changes in the 25(OH)D concentration measured before each OGTT |
| Cardiometabolic risk profile in serum | 4 weeks | Changes in cardiometabolic profile measured in serum before each OGTT |
| Gene expression profile | 4 weeks | peripheral blood mononuclear cells (PBMCs) gene expression |
Countries
Canada
Outcome results
None listed