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

The Study of the Effects of Vitamin A Supplementation on Immune System and Th1/Th2 Balance in Patients With Atherosclerosis

Status
UNKNOWN
Phases
Phase 4
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00963222
Enrollment
60
Registered
2009-08-21
Start date
2009-09-30
Completion date
2013-03-31
Last updated
2012-06-05

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Atherosclerosis

Keywords

Atherosclerosis, Coronary Artery Disease, Vitamin A, CD4-Positive T-Lymphocytes, Th1 Cells, Th2 Cells

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).

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.

Interventions

DRUGvitamin A

1 cap vitamin A 25000 IU/day for 3 month

DRUGplacebo

1 cap placebo/day for 3 month

Sponsors

Tehran University of Medical Sciences
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
35 Years to 60 Years
Healthy volunteers
No

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.

Design outcomes

Primary

MeasureTime frame
PBMC supernatant levels of IL4, IL10, IFN γ, IL2, IL12first day and after 3 month
Serum levels of IL4, IL10, IFN γ, IL2, IL12first day and after 3 month

Secondary

MeasureTime frame
serum triglycerides levelfirst day and after 3 month
serum Apo A, Apo B and CRP levelsfirst day and after 3 month
serum Total cholesterolfirst day and after 3 month
RBP/ TTR ratiofirst day and after 3 month
lymphocyte proliferation assay (MTT)first day and after 3 month
serum oxLDLfirst day and after 3 month
serum HDL cholesterolfirst day and after 3 month

Countries

Iran

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026