Overweight
Conditions
Keywords
Methionine, Cysteine, Energy metabolism, Sulfur amino acids
Brief summary
The aim of this study is to examine the effect of methionine and cysteine restriction on energy and macronutrient metabolism in overweight human subjects
Detailed description
The sulfur-containing amino acid methionine and its downstream metabolite cysteine has been associated with fat mass in animal studies and human observational studies. Some of the proposed mechanisms include an association with lipogenesis, insulin sensitivity and disrupted energy metabolism. The overall aim of this project is to evaluate the effects of a diet low in methionine and cysteine on markers of lipids, amino acids, glucose and other biomarkers related to energy metabolism, including transcriptomic and protein expression data from adipose tissue and lymphocytes. Overweight and obese but otherwise healthy volunteers will be randomized to receive a diet either low, moderate or high in methionine and cysteine concentrations for 1 week. This is a pilot study that may be considered an extension of NCT02647970. In addition to the primary and secondary outcomes we will evaluate the feasibility of the intervention and procedures.
Interventions
BEHAVIORALLow met/cys diet
Dietary intervention with low contents of methionine and cysteine
BEHAVIORALModerate met/cys diet
Dietary intervention with moderate contents of methionine and cysteine
BEHAVIORALHigh met/cys diet
Dietary intervention with high contents of methionine and cysteine
Sponsors
The Research Council of Norway
University of Oxford
University of Oslo
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
DOUBLE (Subject, Investigator)
Masking description
Participant: The diets are similar except for methionine and cysteine, and it is thought that the participants will not be able to identify their treatment allocation by taste. Investigator: Randomization will be carried out by an investigator that is not related to the study. All foods will be pre-packaged and delivered to the participants by an unrelated company.
Eligibility
Sex/Gender
FEMALE
Age
20 Years to 40 Years
Healthy volunteers
Yes
Inclusion criteria
* Body mass index of 25-35 kg/m2
Exclusion criteria
* High physical activity * Smoking * Drugs * Chronic disease * Pregnancy or breastfeeding
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in plasma concentrations of amino acids | Baseline, Day 1, Day 3 and Day 7 (final visit) | Measurement of biomarkers of amino acid metabolism, including plasma concentrations of methionine, cysteine and related metabolites |
| Change in protein expression activity in tissues | Baseline and day 7 (final visit for adipose tissue, Baseline and day 1, 3 and 7 (final visit) for lymphocytes. | Measurement of protein expression and activity related to methionine and cysteine metabolism in adipose tissue and lymphocytes. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in protein expression of steaoryl CoA-desaturase in adipose tissue | Baseline and Day 7 (final visit) | Measurement of protein expression of steaoryl CoA-desaturase in adipose tissue |
| Change in protein expression of steaoryl CoA-desaturase in lymphocytes | Baseline, Day 1, Day 3 and Day 7 (final visit) | Measurement of protein expression of steaoryl CoA-desaturase in lymphocytes |
| Change in steaoryl CoA-desaturase activity in adipose tissue | Baseline and Day 7 (final visit) | Measurement of enzyme activity of steaoryl CoA-desaturase in adipose tissue |
| Change in plasma concentrations of fatty acids | Baseline, Day 1, Day 3 and Day 7 (final visit) | Measurement of fatty acid content in plasma |
| Diet compliance | Baseline, Day 1, Day 3 and Day 7 (final visit) | Compliance with the diet will be measured by a self-administered questionnaire |
| Body composition | Baseline and day 7 (final visit) | Measurement of body composition by bioimpedance and dual X-ray absorptometry |
| Diet feasibility | Baseline, Day 1, Day 3 and Day 7 (final visit) | Diet feasibility will be measured by a self-administered questionnaire |
| Change in plasma activity indices of steaoryl-CoA desaturase | Baseline, Day 1, Day 3 and Day 7 (final visit) | Calculated based onthe ratio of plasma concentrations of products and precursors |
Countries
Norway
Outcome results
None listed