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The Study of the Effects of Vitamin A on Immune System in Patients With Atherosclerosis

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ClinicalTrials.gov Identifier: NCT00963222
Recruitment Status : Unknown
Verified June 2012 by Tehran University of Medical Sciences.
Recruitment status was:  Enrolling by invitation
First Posted : August 21, 2009
Last Update Posted : June 5, 2012
Sponsor:
Information provided by (Responsible Party):
Tehran University of Medical Sciences

Brief Summary:
The aim of this study is the comparison between the effects of supplementation with 25000 IU preformed vitamin A (retinyl palmitate) or placebo for 3 months on immune system and Th1/Th2 balance in patients with and without atherosclerosis (documented with angiography).

Condition or disease Intervention/treatment Phase
Atherosclerosis Drug: vitamin A Drug: placebo Phase 4

Detailed Description:
Atherosclerosis, the leading cause of death and disability in the world, is considered an inflammatory disease with a complex etiology. The immune system has a prominent role in the formation, development and destabilization of atherosclerotic plaques. A whole range of identified cytokines have been shown to play a part in atherogenesis, some with proatherogenic properties while others having antiatherogenic properties. With increasing evidence for the significant role of inflammation and the cytokines involved together with the Th1/Th2 imbalance in atherosclerosis and its progression to Coronary artery diseases (CADs), the control of cytokine production may become potential therapeutic targets and modulation of the Th1/Th2 balance may provide a new pharmacological tool to treat this disease. Vitamin A (VA) or VA-like analogs known as retinoids, are potent hormonal modifiers of type 1 or type 2 responses but a definitive description of their mechanism(s) of action is lacking. high level dietary vitamin A enhances Th2 cytokine production and IgA responses, and is likely to decrease Th1 cytokine production. Retinoic acid inhibits IL 12 production in activated macrophages, and RA pretreatment of macrophages reduces IFNγ production and increases IL4 production in antigen primed CD4 T cells. Supplemental treatment with vitamin A or retinoic acid (RA) decreases IFNγ and increases IL5, IL10, and IL4 production. Thus, vitamin A deficiency biases the immune response in a Th1 direction, whereas high level dietary vitamin A may bias the response in a Th2 direction.

Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 60 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Prevention
Official Title: The Study of the Effects of Vitamin A Supplementation on Immune System and Th1/Th2 Balance in Patients With Atherosclerosis
Study Start Date : September 2009
Primary Completion Date : September 2011
Estimated Study Completion Date : March 2013

Resource links provided by the National Library of Medicine

U.S. FDA Resources

Arm Intervention/treatment
Active Comparator: with atherosclerosis/ vitamin A
patients with angiographically confirmed CAD (defined as luminal stenosis ≥50% in at least one major coronary artery branch)who receive 25000 IU/day vitamin A
Drug: vitamin A
1 cap vitamin A 25000 IU/day for 3 month
Placebo Comparator: with atherosclerosis/ placebo
patients with angiographically confirmed CAD (defined as luminal stenosis ≥50% in at least one major coronary artery branch)who receive placebo
Drug: placebo
1 cap placebo/day for 3 month
Active Comparator: without atherosclerosis/ vitamin A
patients in whom significant (e.g. stenosis ≥ 50%) CAD is ruled out by coronary angiography, who receive 2500 Iu/day vitamin A
Drug: vitamin A
1 cap vitamin A 25000 IU/day for 3 month
Placebo Comparator: without athrosclerosis/ placebo
patients in whom significant (e.g. stenosis ≥ 50%) CAD is ruled out by coronary angiography, who receive placebo
Drug: placebo
1 cap placebo/day for 3 month



Primary Outcome Measures :
  1. Serum levels of IL4, IL10, IFN γ, IL2, IL12 [ Time Frame: first day and after 3 month ]
  2. PBMC supernatant levels of IL4, IL10, IFN γ, IL2, IL12 [ Time Frame: first day and after 3 month ]

Secondary Outcome Measures :
  1. serum Total cholesterol [ Time Frame: first day and after 3 month ]
  2. serum HDL cholesterol [ Time Frame: first day and after 3 month ]
  3. serum triglycerides level [ Time Frame: first day and after 3 month ]
  4. serum Apo A, Apo B and CRP levels [ Time Frame: first day and after 3 month ]
  5. serum oxLDL [ Time Frame: first day and after 3 month ]
  6. RBP/ TTR ratio [ Time Frame: first day and after 3 month ]
  7. lymphocyte proliferation assay (MTT) [ Time Frame: first day and after 3 month ]


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Ages Eligible for Study:   35 Years to 60 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • The criteria for enrollment of the patients and control subjects is consecutive patients of both sexes referred to the Division of Cardiology of the one of the Hospitals of Tehran University of Medical Sciences for coronary angiography for investigation of chest pain and/or suspected CAD.

Exclusion Criteria:

  • Patients who have diseases which affect on Th1/Th2 balance such as asthma, active viral infections, and autoimmune diseases, OR
  • Patients who have allergy to vitamin A compounds, OR
  • Patients who have used vitamin supplements in last 3 months.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00963222


Locations
Iran, Islamic Republic of
Tehran University of Medical Sciences, School of Public Health
Tehran, Iran, Islamic Republic of
Sponsors and Collaborators
Tehran University of Medical Sciences
Investigators
Study Chair: Ali Akbar saboor Yaraghi, PhD Tehran University of Medical Sciences
Principal Investigator: Maryam Mahmoudi, MD, PhD student Tehran University of Medical Siences
Study Chair: Fereidon Siassi, PhD Tehran University of Medical Sciences

Responsible Party: Tehran University of Medical Sciences
ClinicalTrials.gov Identifier: NCT00963222     History of Changes
Other Study ID Numbers: 86-04-27-6617
First Posted: August 21, 2009    Key Record Dates
Last Update Posted: June 5, 2012
Last Verified: June 2012

Keywords provided by Tehran University of Medical Sciences:
Atherosclerosis
Coronary Artery Disease
Vitamin A
CD4-Positive T-Lymphocytes
Th1 Cells
Th2 Cells

Additional relevant MeSH terms:
Atherosclerosis
Arteriosclerosis
Arterial Occlusive Diseases
Vascular Diseases
Cardiovascular Diseases
Vitamins
Vitamin A
Retinol palmitate
Micronutrients
Growth Substances
Physiological Effects of Drugs
Antioxidants
Molecular Mechanisms of Pharmacological Action
Protective Agents
Anticarcinogenic Agents
Antineoplastic Agents