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

Atherosclerosis Clinical Trial

Official title:

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

Clinical Trial Details — Status: Enrolling by invitation

Administrative data

• NCT number: NCT00963222
• Other study ID #: 86-04-27-6617
• Status: Enrolling by invitation
• Phase: Phase 4
• First received: August 20, 2009
• Last updated: June 2, 2012
• Start date: September 2009
• Est. completion date: March 2013

Study information

• Verified date: June 2012
• Source: Tehran University of Medical Sciences
• Contact: n/a
• Is FDA regulated: No
• Health authority: Iran: Ministry of Health
• Study type: Interventional

Clinical Trial 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).

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.

Recruitment information / eligibility

• Status: Enrolling by invitation
• Enrollment: 60
• Est. completion date: March 2013
• Est. primary completion date: September 2011
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 35 Years to 60 Years

Eligibility

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.

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Primary Purpose: Prevention

Related Conditions & MeSH terms

• Atherosclerosis

Intervention

Drug:
• vitamin A
1 cap vitamin A 25000 IU/day for 3 month
• placebo
1 cap placebo/day for 3 month

Locations

Country	Name	City	State
Iran, Islamic Republic of	Tehran University of Medical Sciences, School of Public Health	Tehran

Sponsors (1)

Lead Sponsor	Collaborator
Tehran University of Medical Sciences

Country where clinical trial is conducted

Iran, Islamic Republic of, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Serum levels of IL4, IL10, IFN ?, IL2, IL12		first day and after 3 month	No
Primary	PBMC supernatant levels of IL4, IL10, IFN ?, IL2, IL12		first day and after 3 month	No
Secondary	serum Total cholesterol		first day and after 3 month	No
Secondary	serum HDL cholesterol		first day and after 3 month	No
Secondary	serum triglycerides level		first day and after 3 month	No
Secondary	serum Apo A, Apo B and CRP levels		first day and after 3 month	No
Secondary	serum oxLDL		first day and after 3 month	No
Secondary	RBP/ TTR ratio		first day and after 3 month	No
Secondary	lymphocyte proliferation assay (MTT)		first day and after 3 month	No