VITAMIN E

• Vitamin E has been shown to be essential for integrity and optimum function of reproductive, muscular, circulatory, nervous and immune systems .
• It is well established that some functions of vitamin E, however, can be fulfilled in part or entirely by traces of selenium .
• It is well established that some functions of vitamin E, however, can be fulfilled in part or entirely by traces of selenium .

FUNCTIONS OF VITAMIN E:

1. Vitamin E as a Biological Antioxidant
2. Membrane Structure and Prostaglandin Synthesis
3. Disease Resistance

1.Vitamin E as a Biological Antioxidant.

• The most important functions is its role as an intercellular and intracellular antioxidant.
• Therefore, antioxidants are very important to immune defense and health of humans and animals.
• Vitamin E is part of the body’s intracellular defense against the adverse effects of reactive oxygen and free radicals that initiate oxidation of unsaturated phospholipids.
• Vitamin E functions as a membrane-bound antioxidant, trapping lipid peroxyl free radicals produced from unsaturated fatty acids under conditions of “oxidative stress.”

Mechanism of action:

• Vitamin E reacts or functions as a chain-breaking antioxidant thereby neutralizing free radicals and preventing oxidation of lipids within membranes. So, interrupt production of free radicals at the initial stage.

2.Membrane Structure and Prostaglandin Synthesis

• Alpha-tocopherol may be involved in the formation of structural components of biological membranes, thus exerting a unique influence on architecture of membrane phospholipids .
• It is reported that alpha-tocopherol stimulated the incorporation of 14C from linoleic acid into arachidonic acid in fibroblast phospholipids.
• Also, it was found that alpha-tocopherol exerted a pronounced stimulatory influence on formation of prostaglandin E from arachidonic acid.
• vitamin E supplementation of diets increased intracellular kill of  Staphylococcus aureus and Escherichia coli by neutrophils.

3.Disease Resistance

• vitamin E is an essential nutrient for the normal function of the immune system.
• vitamin E and selenium play role in protecting leukocytes and macrophages during phagocytosis, the mechanism whereby animals immunologically kill invading bacteria.
• Both vitamin E and selenium may help these cells survive the toxic products that are produced in order to effectively kill ingested bacteria.
• Macrophages and neutrophils from vitamin E-deficient animals have decreased phagocytic activity.
• The protective effects of vitamin E on animal health may be involved with its role in reduction of glucocorticoids, which are known to be immunosuppressive

Selenium 

Selenium (Se) is an essential trace element in animal nutrition, and exerts multiple actions related to animal production, fertility and disease prevention. Glutathione peroxidase (GSH-PX) enzyme was the first proven selenoenzyme that can prevent oxidative damage of the cellular membrane.

Selenium deficiency

In poultry:
Exudative diathesis (ED):

• • ED occurs as a result of selenium deficiency in chickens, and it primarily affects the capillary walls.
  • Clinical signs observed include :
    greenish-blue discoloration of the skin in localized areas of the chick’s body, along with edema and hemorrhages, often resulting in bow-legged posture and pendulous (loosely hanging) crop in the throat latch area.

Combination between vitamin E and selenium??

• There is a close working relationship between vitamin E and selenium within tissues.
• Selenium has a sparing effect on vitamin E and delays onset of deficiency signs. Likewise, vitamin E and sulfur amino acids partially protect against or delay onset of several forms of selenium deficiency syndromes.
• Tissue breakdown occurs in most species receiving diets deficient in both vitamin E and selenium, mainly through peroxidation.
• Peroxides and hydroperoxides are highly destructive to tissue integrity and lead to disease development.

It now appears that vitamin E in cellular and subcellular membranes is the first line of defense against peroxidation of vital phospholipids ,but even with adequate vitamin E, some peroxides are formed.

• Selenium, as part of the enzyme GSH-Px, is a second line of defense that destroys these peroxides before they have an opportunity to cause damage to membranes.
• Therefore, selenium, vitamin E and sulfur-containing amino acids, through different biochemical mechanisms, are capable of preventing some of the same nutritional diseases.
• Vitamin E prevents fatty acid hydroperoxide formation, sulfur amino acids are precursors of GSH-Px, and selenium is a component of GSH-Px.
• Semen quality improved with selenium and vitamin E supplementation, in which vitamin E helped maintain sperm integrity in combination with selenium .
• Vitamin E and selenium appear to enhance host defenses against infections by improving phagocytic cell function.
• Both vitamin E and GSH-Px are antioxidants that protect phagocytic cells and surrounding tissues from oxidative attack by free radicals produced by the respiratory burst of neutrophils and macrophages during phagocytosis.

Zinc sulphate monohydrate

• The mineral zinc plays an important role in many substances in the body including enzymes, proteins, and hormones.
• Zinc is also important for immune system function and thyroid function.
•  is involved in the production of numerous hormones (thyroid hormone, insulin, sex hormones, growth hormone, cortisone).
• plays an integral role in DNA synthesis, and therefore cellular reproduction.
• Zinc also plays a major role in brain function, learning and memory, as well as maintaining good eyesight.
• In the skin, zinc plays a role in maintaining healthy skin and is involved in hair growth and regulation.
• It is also vital to normal skeletal development and collagen synthesis.
• Zinc is also one of the more powerful anti-oxidants in the body.

Combination of zinc and selenium as antioxidants?????????
Zinc, selenium and the combination significantly:

1. reduce blood glucose concentration.
2. restorehepatic functions.
3. increase the antioxidant status and reduced lipid peroxidation in both the hepatic and renal tissues.