This study was carried out to evaluate the status of some antioxidant vitamin in patient with acute myocardial infarction. A total of 45 subjects aged between 30 to 65 years were recruited for the study and they were divided into two (2) Group, group 1 comprises of 15 subjects with AMI and group 2 comprises of 30 subjects without AMI. The subject were recruited from the cardiology unit of the F.M.C, Owerri after due ethical procedures and clearance. Blood sample were collected from them for the analysis of vitamin A, C, E and D using Elisa kits based on modified enzyme linked immunoassay method. The result obtained showed a significant decrease (P< 0.05) in vitamin E (0.44±0.09mg/dl) in test when compared with vitamin E (1.46±0.22mg/dl) in the control. There was also a significant decrease (P<0.05) vitamin C (0.74±0.15mg/dl) in test when compared with the vitamin C (1.31±0.27mg/dl) in the control. The test also showed significant decrease (P<0.05) in vitamin D (14.86±1.86mg/dl) in test when compared with vitamin C (32.04±2.50mg/dl) in the control. Also there is a significant decrease (P<0.05) in vitamin A (18.38±4.65 mg/dl) in test when compared with vitamin A (43.48±8.15mg/dl) in the control. Therefore there is cardioprotective effect of antioxidant vitamin due to its reduction in acute myocardial infarction. However, supplementation of the antioxidant vitamin can scavenge free radicals preventing cardiac oxidative stress which increases the risk of acute myocardial infarction.



  • Introduction

An antioxidant is a molecule that inhibits the oxidation of other molecules. Oxidation is a chemical reaction that can produce free radicals, leading to chain reactions that may damage cells. Antioxidants such as thiols or ascorbic acid (vitamin C) terminate these chain reactions. The term “antioxidant” is mainly used for two different groups of substances: industrial chemicals which are added to products to prevent oxidation, and natural chemicals found in foods and body tissue which are said to have beneficial health effects.

To balance the oxidative state, plants and animals maintain complex systems of overlapping antioxidants, such as glutathione and enzymes (e.g., catalase and superoxide dismutase) produced internally or the dietary antioxidants: vitamin A, vitamin C, and vitamin E.

Ascorbic acid or “vitamin C” is a monosaccharide oxidation-reduction (redox) catalyst found in both animals and plants. As one of the enzymes needed to make ascorbic acid has been lost by mutation during primateevolution, humans must obtain it from the diet; it is therefore a vitamin (Smirnoff, 2001). Most other animals are able to produce this compound in their bodies and do not require it in their diets (Linster et al., 2007). Ascorbic acid is required for the conversion of the procollagen to collagen by oxidizing proline residues to hydroxyproline. In other cells, it is maintained in its reduced form by reaction with glutathione, which can be catalysed by protein disulfide isomerase and glutaredoxins (Meister, 1994; Wells et al., 1990). Ascorbic acid is a redox catalyst which can reduce, and thereby neutralize, reactive oxygen species such as hydrogen peroxide (Padayatty et al., 2003). In addition to its direct antioxidant effects, ascorbic acid is also a substrate for the redox enzyme ascorbate peroxidase, a function that is particularly important in stress resistance in plants (Shigeoka et al., 2002). Ascorbic acid is present at high levels in all parts of plants and can reach concentrations of 20 millimolar in chloroplasts (Smirnoff and Wheeler, 2000).

Vitamin E is the collective name for a set of eight related tocopherols and tocotrienols, which are fat-soluble vitamins with antioxidant properties (Herrera and Barbas, 2001; Packer et al., 2001). Of these, α-tocopherol has been most studied as it has the highest bioavailability, with the body preferentially absorbing and metabolising this form (Brigelius and Traber, 1999).

It has been claimed that the α-tocopherol form is the most important lipid-soluble antioxidant, and that it protects membranes from oxidation by reacting with lipid radicals produced in the lipid perioxidation chain reaction (Herrera and Barbas, 2001; Traber and Atkinson, 2007). This removes the free radical intermediates and prevents the propagation reaction from continuing. This reaction produces oxidised α-tocopheroxyl radicals that can be recycled back to the active reduced form through reduction by other antioxidants, such as ascorbate, retinol or ubiquinol (Wang and Quinn, 1999). This is in line with findings showing that α-tocopherol, but not water-soluble antioxidants, efficiently protects glutathione peroxidase 4 (GPX4)-deficient cells from cell death (Seiler et al., 2008). GPx4 is the only known enzyme that efficiently reduces lipid-hydroperoxides within biological membranes.

However, the roles and importance of the various forms of vitamin E are presently unclear, (Brigelius and Davies, 2007; Atkinson et al., 2008), and it has even been suggested that the most important function of α-tocopherol is as a signaling molecule, with this molecule having no significant role in antioxidant metabolism (Azzi, 2007; Zingg and Azzi, 2004). The functions of the other forms of vitamin E are even less well understood, although γ-tocopherol is a nucleophile that may react with electrophilic mutagens, (Brigelius and Traber, 1999) and tocotrienols may be important in protecting neurons from damage (Sen et al., 2006).

Vitamin A is a group of unsaturated nutritional organic compounds that includes retinol, retinal, retinoic acid, and several provitamin A carotenoids (most notably beta-carotene), (Fennema and Owen, 2008). Vitamin A has multiple functions: it is important for growth and development, for the maintenance of the immune systemand good vision (Tanumihardjo, 2011). Vitamin A is needed by the retina of the eye in the form of retinal, which combines with protein opsin to form rhodopsin, the light-absorbing molecule (Wolf, 2001) necessary for both low-light (scotopic vision) and color vision. Vitamin A also functions in a very different role as retinoic acid (an irreversibly oxidized form of retinol), which is an important hormone-like growth factor for epithelial and other cells (Tanumihardjo, 2011).

Vitamin D refers to a group of fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, and multiple other biological effects. In humans, the most important compounds in this group are vitamin D3 (also known as cholecalciferol) and vitamin D2 (ergocalciferol), (Holick, 2006). Cholecalciferol and ergocalciferol can be ingested from the diet and from supplements (Holick, 2006; Calvo et al., 2005; Norman et al., 2008). Only a few foods contain vitamin D. The major natural source of the vitamin is synthesis of cholecalciferol in the skin from cholesterol through a chemical reaction that is dependent on sun exposure (specifically UVB radiation).



1.1 Justification

Antioxidants are presently of interest for their potential role in inhibiting atherosclerosis, thus preventing some major clinical complications of atherosclerosis such as myocardial infarction. α-Tocopherol and several carotenoids have been shown to act as antioxidants (Burton et al., 1983). They have been suggested to trap free radicals by breaking the chain reaction of lipid peroxidation. Having seen little or non of such studies being conducted here, especially now that heart disease is  becomingrampant, this study is timely.  This study will show the relationship between the levels of some antioxidant vitamins in the subject with myocardial infarction.

1.2 Research Question

Does the level of antioxidant vitamins have any relationship with Myocardial Infarction?

1.3 Aim                                                                                                     

The aim of this study is to investigate the levels of vitamin A, vitamin C, vitamin D and vitamin E in patients with myocardial infarction.


1.4 Objectives

The objectives of the study are:

  1. To determine the blood levels of the trio antioxidants vitamins, A, C, and E in subjects with myocardial infarction.
  2. To determine the blood levels of vitamin D in subjects with myocardial infarction.

3. To determine the blood level of the trio antioxidant vitamins A, C, E and vitamin D in apparently healthy subject, without acute myocardial infarction