Clinical trial NCT01351324: A Study of Different Types of Fatty Acid on Risk Factors for Heart Disease
Official title: Acute Elevation of Non-esterified Fatty Acids on Endothelial Function and Insulin Sensitivity: A Comparison of Saturated and Long Chain n-3 Polyunsaturated Fatty Acids During the Postprandial Phase
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Cardiovascular Risk Factors
Keywords: Endothelial function
Non-esterified fatty acids
Insulin sensitivity
Lead sponsor: University of Reading
Sponsor class: OTHER
Collaborators: name: Biotechnology and Biological Sciences Research Council
name: Unilever R&D
name: Foundation for Research Science and Technology (New Zealand)
First posted: 2011-05-10
Enrollment: 59
Sex: ALL
Minimum age (years): 18
Maximum age (years): 60
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: BASIC_SCIENCE

Brief summary: Experimental elevation of non-esterified fatty acids (NEFA) impairs endothelial function and insulin sensitivity but the impact of NEFA composition is unknown.

The objective was to test the effect of acute elevation of NEFA enriched with either saturated fatty acids (SFA) or SFA with long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA) on postprandial vascular function measured via flow-mediated dilatation (FMD), laser Doppler iontophoresis (LDI) and digital volume pulse (DVP), followed by a hyperinsulinaemic-euglycaemic clamp as a measure of whole body insulin sensitivity.

Detailed description: To investigate potential diet-gene interactions, potential subjects (n=370) were prospectively genotyped for the eNOS Glu298Asp polymorphism, of which 35 were Asp298 and 150 were Glu298 homozygotes. Three subjects in the Asp298 group were unable to participate, two were unsuitable according to selection criteria and one subject subsequently withdrew from the study. Subjects homozygous for Asp298 (n=29) and Glu298 (n=30) were therefore selected, balanced for gender, age and BMI.

Eligibility criteria: Inclusion Criteria:

* Healthy
* Either homozygous for eNOS Glu298 (wildtype)or eNOS Asp298 (variant)

Exclusion Criteria:

* Smokers
* Raised fasting blood lipids
* Taking excessive fish oil supplements (\>1g EPA/DHA per day)
* Taking medication known to influence blood lipids, blood pressure or blood clotting

Primary outcomes:
measure: Flow-mediated dilatation
timeFrame: Change from baseline to 240 min
measure: Flow-mediated dilatation
timeFrame: Change from 240 min to 390 min
Secondary outcomes:
measure: Digital volume pulse
timeFrame: Change from baseline to 240 min
measure: Laser Doppler iontophoresis
timeFrame: Change from baseline to 240 min
measure: Insulin sensitivity
timeFrame: 390 min
measure: NEFA composition
timeFrame: Change from baseline to 240 min
measure: Circulating endothelial function markers
timeFrame: Change from baseline to 240 min
measure: Digital volume pulse
timeFrame: Change from 240 min to 390 min
measure: Laser Doppler iontophoresis
timeFrame: Change from 240 min to 390 min
measure: Circulating endothelial markers
timeFrame: Change from 240 min to 390 min
Other outcomes:
Locations:
city: Reading
country: United Kingdom
facility: University of Reading
Study officials:
affiliation: University of Reading
name: Christine M Williams
role: PRINCIPAL_INVESTIGATOR
References:
citation: Newens KJ, Thompson AK, Jackson KG, Williams CM. Endothelial function and insulin sensitivity during acute non-esterified fatty acid elevation: Effects of fat composition and gender. Nutr Metab Cardiovasc Dis. 2015 Jun;25(6):575-81. doi: 10.1016/j.numecd.2015.03.004. Epub 2015 Mar 14.
citation: Newens KJ, Thompson AK, Jackson KG, Wright J, Williams CM. DHA-rich fish oil reverses the detrimental effects of saturated fatty acids on postprandial vascular reactivity. Am J Clin Nutr. 2011 Sep;94(3):742-8. doi: 10.3945/ajcn.110.009233. Epub 2011 Aug 10.