Fatty Acid Desaturase Gene Locus Interactions With Diet (FADSDIET2)

Genetics Clinical Trial

— FADSDIET2  

Official title:

Fatty Acid Desaturase Gene Locus Interactions With Diet (FADSDIET2)

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03572205
• Other study ID #: FADSDIET2
• Status: Completed
• Phase: N/A
• Start date: August 13, 2018
• Est. completion date: December 19, 2018

Study information

• Verified date: April 2019
• Source: University of Eastern Finland
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Interactions between genes and environment, are likely to be crucial in the development of the common diseases such as type 2 diabetes. Recently, the investigators have obtained data that genotypes of genes encoding for fatty acid desaturases 1 and 2 (FADS1 and FADS2) are the strongest genes in a genome-wide analysis regulating serum fatty acid profile.The aim of this study is to test if subjects with different genotypes of the FADS2 gene respond differently to a diet supplemented with linoleic acid or alpha-linolenic acid (substrates for FADS2). The study hypothesizes that subjects will be more sensitive to the dietary modifications according to their genotype leading to more robust differences in serum FA profile, tissue inflammation and serum lipids.

Description:

Lean and overweight subjects (Body mass index: BMI >20kg/m2 <32kg/m2 ) with CC and TT genotypes of FADS1 single nucleotide polymorphism (SNP) from the METabolic Syndrome in Men (METSIM) study, in which currently >10000 men are included from the population living in Kuopio, will be recruited. Seventy subjects with CC genotype will be selected after matching with the 70 subjects with the TT genotype for age and BMI.

After a 4-week run-in period, the subjects within each genotype group will be randomly assigned into two study groups according to medians of BMI, age and fasting plasma glucose concentration: in one group the diet will be enriched with linoleic acid (LA, sunflower oil) and in the other group with alpha-linolenic acid (ALA, camelina oil). The intervention will last for 8 weeks.

The sample size calculation is based on the observed change in arachidonic acid (AA) in the cholesterol esthers fraction between CC and TT genotypes (12.14 vs. 4.20 mol%, respectively) after the diet enriched in LA from preliminary data. Considering a β=0.80 and an α=0.025 instead of only 0.05 to account for the fact that we now have two dietary interventions instead of one, 31 participants in each study group would need to be included. Assuming around 15% of dropouts in this trial, a final sample size of 35 for each group is required.

The study diet will be isocaloric following the habitual diet of the participants with a supplement of 30-50 ml (25-45 g) sunflower or camelina oil daily depending on body weight. The dose of each oil is not known to cause any side effects or adverse events and even higher doses have been safe.

Participants will record their daily oil consumption and 4-day food records will be collected at the beginning and two times during the intervention period to measure daily intake of macronutrients and specifically different fatty acids.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 140
• Est. completion date: December 19, 2018
• Est. primary completion date: December 19, 2018
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Male
• Age group: 50 Years to 65 Years

Eligibility

Inclusion Criteria:

• Participants of METSIM study cohort with CC/TT FADS1 rs174547 SNP genotype.

• BMI 20-32 kg/m2.

• Healthy .

Exclusion Criteria:

• Diagnosis of type 2 diabetes.

• Diagnosis of chronic diseases and conditions, that may hamper the ability to follow the dietary intervention protocol

• Chronic liver, thyroid and kidney diseases

• Alcohol abuse (> 40 g/d)

• BMI >32 kg/m2.

Related Conditions & MeSH terms

• Fatty Acids
• Genetics

Intervention

Dietary Supplement:
• LA
The source of linoleic acid (LA) will be sunflower oil (62-63 % LA). The study diets will be isocaloric. The allowed weight change during the study is ± 2-3 %. The amount of supplementary oil will be calculated individually based on the calculated energy expenditure and adjusted, if necessary, during the study based on body weight measurements.
• ALA
The source of alpha-linolenic acid (ALA) will be camelina sativa oil (30-35 % ALA). The study diets will be isocaloric. The allowed weight change during the study is ± 2-3 %. The amount of supplementary oil will be calculated individually based on the calculated energy expenditure and adjusted, if necessary, during the study based on body weight measurements.

Locations

Country	Name	City	State
Finland	University of Eastern Finland	Kuopio

Sponsors (1)

Lead Sponsor	Collaborator
University of Eastern Finland

Country where clinical trial is conducted

Finland, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Change in fatty acid composition of serum lipid fractions	Fatty acid composition of serum lipid fractions	8 weeks
Secondary	Glucose and insulin metabolism response	Oral glucose tolerance test (OGTT) variables: fasting, 30 min and 120 min glucose and insulin measurements	8 weeks
Secondary	Inflammatory markers response	Serum circulating levels of high-sensitivity C-reactive protein	8 weeks
Secondary	Adipose tissue biopsies	Subcutaneous adipose tissue taken by open biopsy to collect 1-5 g of adipose tissue.	8 weeks