Retinoic Acid Supplementation and Subjects With Hypercholesterolemia

Study Overview
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Brief Summary
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The aim of the study is to investigate the effects of retinoic acid on the HDL-PON1 activity and cholesterol efflux capacity in hypercholesterolemic subjects.

Detailed Description
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Paraoxonase 1 (PON1), an enzyme associated with high-density lipoprotein, is reported to have antioxidant and cardioprotective properties. And all-trans-retinoic acid revealed the ameliorating atherosclerosis effects in many reports.There maybe some correlations between retinoic acid and PON1 activity and the study aim to prove it.

Official Title
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Effect of Retinoic Acid Supplementation on the HDL-Associated Paraoxonase 1 Activity in Subjects With Hypercholesterolemia: A Randomized, Double-Blinded, Placebo-Controlled Trial

Conditions
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Hypercholesterolemia

Intervention / Treatment
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* Dietary Supplement: retinoic acid
* Other: placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: subject has a fasting total cholesterol concentration between 200 and 310mg/dl. subject is between 25 and 65 years of age, inclusive. subjects' BMI is between 18.5 kg/m2 and 35 kg/m2. Exclusion Criteria: subject that is pregnant. subject that has coronafy artery desease, diabetes mellitus, thyroid disorders, mental disorder, cancer, cirrhosis, renal disease and hepatic desease. subject that has had operation less than six months prior to screening visit. subject that is smoking. subject uses any drugs that could influence the measurement of lipid paramerters or inflammatiory makers.

Ages Eligible for Study
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Minimum Age: 25 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: control<br>the participants in this arm are instruted to consume placebo capsules | Other: placebo<br>* During the trial period, the participants are instructed to consume placebo capsules twice daily (30 min after breakfast and supper).The placebo capsules are composed of starch and pigment.<br>|
| Experimental: treatment<br>the participants in this arm are instruted to consume retinoic acid capsules | Dietary Supplement: retinoic acid<br>* During the trial period, the participants are instructed to consume retinoic acid capsules twice daily (30 min after breakfast and supper).The retinoic acid capsules provided a total daily intake of 10 mg of retinoic acid.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| PON1 activity | PON1 activity is assayed in HDL isolated from plasma of subjects from the placebo and retinoic acid groups by using UV spectrophotometry in a 96-well plate format using phenyl acetate or paraoxon as substrates. | changes from baseline in PON1 activity at 12 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Lp-PLA2 activity | Lp-PLA2 activity in apoB-depleted plasma after the sedimentation of all apoB-containing lipoproteins with dextran sulfate-magnesium chloride is determined using the trichloroacetic acid precipitation procedure using 2-thio platelet-activation factor as a substrate. | changes from baseline in Lp-PLA2 activity at 12 weeks |