A Phase 4 interventional study of vitamin A and placebo in Atherosclerosis, sponsored by Tehran University of Medical Sciences. Status unknown at 1 site in Iran, Islamic Republic of. Open to participants aged 35 Years to 60 Years. Per ClinicalTrials.gov, last updated 2012-06-05.
Sponsored by Tehran University of Medical Sciences · Phase 4, Interventional, and Prevention
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).
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.
1,567 studies on the registry are indexed under Atherosclerosis; 264 are open to participants now.
This study's planned enrollment of 60 is below the median of 106 across 882 interventional studies indexed under Atherosclerosis.
Browse Atherosclerosis studies →Tehran University of Medical Sciences is the lead sponsor of 227 studies on the registry; 12 are open to participants now.
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Exclusion Criteria:
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
patients with angiographically confirmed CAD (defined as luminal stenosis ≥50% in at least one major coronary artery branch)who receive placebo
Drug: placebo
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
patients in whom significant (e.g. stenosis ≥ 50%) CAD is ruled out by coronary angiography, who receive placebo
Drug: placebo
1 cap vitamin A 25000 IU/day for 3 month
1 cap placebo/day for 3 month
Serum levels of IL4, IL10, IFN γ, IL2, IL12
Time frame: first day and after 3 month
PBMC supernatant levels of IL4, IL10, IFN γ, IL2, IL12
Time frame: first day and after 3 month
serum Total cholesterol
Time frame: first day and after 3 month
serum HDL cholesterol
Time frame: first day and after 3 month
serum triglycerides level
Time frame: first day and after 3 month
serum Apo A, Apo B and CRP levels
Time frame: first day and after 3 month
serum oxLDL
Time frame: first day and after 3 month
RBP/ TTR ratio
Time frame: first day and after 3 month
lymphocyte proliferation assay (MTT)
Time frame: first day and after 3 month
This study is status unknown, as verified in Jun 2012. You cannot join it, but the record below documents what was studied.
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Tehran University of Medical Sciences