Clinical trial NCT02952638: Dietary Sources of Lysophospholipids
Official title: Dietary Sources of Lysophospholipids
Study type: OBSERVATIONAL
Overall status: TERMINATED
Conditions: Obesity
Cardiovascular Risk Factor
Hyperlipidemia
Keywords: Lipids
lysophosphatidic acid
Lysophospholipids
phosphatidylcholine
lysophosphatidylcholine
autotaxin
dietary
Lead sponsor: University of Kentucky
Sponsor class: OTHER
First posted: 2016-11-02
Enrollment: 44
Sex: ALL
Minimum age (years): 18
Maximum age (years): 60
Standard ages: ADULT
Accepts healthy volunteers: yes
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Subjects 18 years of age or older with no major health issues

Brief summary: This study aims to test the hypothesis that dietary intake of phosphatidylcholine (PC) and lysophosphatidylcholine (LPC) acutely alters plasma lysophosphatidic acid (LPA) levels and autotaxin activity in normal weight and obese subjects.

Detailed description: Lysophosphatidic acid (LPA) is a simple glycerophospholipid that is found at biologically-relevant levels in plasma and has important effects on isolated or cultured blood, vascular and fat cells. The main enzyme responsible for generation of plasma LPA is the secreted lysophospholipase D, autotaxin (ATX). Adipocytes contribute substantially to plasma ATX levels. The investigators have demonstrated rapid production and metabolism of plasma LPA in animals. More recently, the investigators have observed that plasma LPA levels increase in mice fed a high fat ("Western") diet in comparison to levels found in mice fed normal chow. The investigators have also found that diet-induced obesity increased circulating ATX levels in mice. The investigators hypothesize that diet, and in particular dietary phosphatidylcholine (PC), may regulate the autotaxin substrate lysophosphatidylcholine (LPC), from which LPA is derived. Obesity may amplify the response by increasing plasma ATX levels and/or activity. The current study will test whether dietary PC in normal weight and obese subjects acutely alters LPA levels and autotaxin activity.

Eligibility criteria: Inclusion Criteria:

* Age 18 to 60 years old
* Body Mass Index of 20 and above
* Must be able to consume a low fat meal, unlimited fruits and vegetables and not eating after midnight the night before the lipid tolerance test
* Report to the clinical research unit fasting (no food since the meal the night before)
* Able to consume a liquid meal consisting of a commercial nutritional product supplemented with fat
* Able to have an indwelling catheter placed on one arm and have hourly blood draws for 8 hours

Exclusion Criteria:

* Unstable medical condition (recent or unstable cardiovascular disease)
* Active cancer
* Renal insufficiency Glomerular Filtration Rate \<30
* Use of steroids
* Chronic inflammatory conditions
* Use of anticoagulants, anti-inflammatory, or lipid-lowering medications
* Lipodystrophy
* GI conditions that result in lipid intolerance
* Pregnant women have a tendency to be anemic and therefore will be excluded.

Primary outcomes:
measure: Plasma Autotaxin-dependent formation of Lysophosphatidic acid, and Levels of Phosphatidylcholine and its metabolites - Lysophosphatidylcholine, Lysophosphatidic acid, Choline, Trimethylamine and Trimethylamine oxide measured by Tandem Mass Spectrometry
timeFrame: 8 hours
Secondary outcomes:
Other outcomes:
Locations:
city: Lexington
country: United States
facility: University of Kentucky Dept of Cardiology
state: Kentucky
Study officials:
affiliation: University of Kentucky
name: Susan S Smyth, MD, PhD
role: PRINCIPAL_INVESTIGATOR
References: