Vitamin E (alpha-tocopherol)

What sample is needed for Vitamin E (α-Tocopherol)?

1. The patient’s plasma is needed. For plasma, take a sample in heparin.
2. A fasting sample is preferred.
3. The sample is stable at 4 °C for 4 weeks and at -20 or -70 °C for one year.
4. Protect from light.

What are the precautions for Vitamin E?

1. Avoid the use of alcohol at least 24 hours before taking the blood sample.
2. Protect the sample from light.

How will you define Vitamin E?

1. Vitamin E is an antioxidant and free radical scavenger, especially in the cell membranes.
2. It is a fat-soluble vitamin.
3. It protects cells from oxidative stress.
4. α-Tocopherol is only used by humans.

What is the history of Vitamin E?

1. In 1920, vegetable oil was the factor that caused deficient resorption in deficient rats.
2. Later on, the name tocopherol was given.
3. Vitamin E has several biologically active isomers.
4. The word tocopherol is a Greek-derived name.
5. Its fertility role is still questionable.
6. α-tocopherol is the most common biologically active isomer in the blood.

How will you discuss the pathophysiology of Vitamin E?

1. This is a powerful antioxidant vitamin.
   1. Oxidants’ role is to cause disease, aging, and cleavage of fatty acids.
2. Vitamin E is soluble in fat solvents and insoluble in water.
3. Its generic name is tocopherol, and it includes several biologically active isomers.
4. α-tocopherol is the predominant isomer and is the biologically active form.
   1. It is viscous oil at room temperature.
   2. Stable to heat in the absence of oxygen.
5. It plays a role in cellular respiration.
6. Vitamin E contains 8 related natural compounds that are biosynthesized in plants and are abundant in vegetables.
   1. Eight Vitamin E subtypes are tocopherols and tocotrienols.
   2. Its most active unit is α-tocopherol.
7. Its main function is antioxidants.

What are the isomers of Vitamin E?

1. α-Tocopherol (Alpha-Tocopherol).
2. β-Tocopherol (Beta-Tocopherol).
3. γ-Tocopherol (Gamma-Tocopherol).
4. δ-Tocopherol (Delta-Tocopherol).
5. ζ-Tocopherol (Zeta-Tocopherol).
6. ε-Tocopherol (Epsilon-Tocopherol).
7. η-Tocopherol (Eta-Tocopherol).
8. 8-Methyl-tocotrienol.

What is the mechanism of the absorption of vitamin E?

1. Its absorption takes place in the presence of bile in the small intestine.
   1. Most of the tocopherol enters the bloodstream via lymph.
2. So, it is associated with chylomicron and very low-density lipoprotein.
3. About 40% of the ingested tocopherol is absorbed.
4. The physiological requirements of vitamin E (Tocopherol) increase with increasing polyunsaturated fatty acids in the diet.
5. Absorbed vitamin E (tocopherol) is first associated with circulating chylomicron and VLDL.
6. Some vitamin E (Tocopherol) is transferred to adipose tissue during triglyceride hydrolysis.

What are the sources of vitamin E?

1. Vegetable oils.
2. Fresh leafy vegetables.
3. Eggs and yolk.
4. Legumes.
5. Peanuts and seeds.
6. Margarine.
7. Most of it is stored in the adipose tissue.

What is the metabolism of Vitamin E?

1. Vitamin E (Tocopherol) absorption, transportation, and storage are partially understood.
2. Vitamin E (Tocopherol) is absorbed along with chylomicron and VLDL.
3. Bile salt is needed for its absorption.

4. When the normal dose of Vitamin E is given, a very small amount appears in the urine.

What are the functions of  Vitamin E?

1. Vitamin E (tocopherol) is an Antioxidant.
2. The specific role of humans is unclear.
3. It protects unsaturated fatty acids from peroxidation (it is the cleavage of fatty acids).
   1. Cleavage of fatty acids at their unsaturated sites by oxygen addition across the double bond and formation of free radicals.
4. Protect from free radicals.
5. Prevent the oxidation of the cell membrane’s vitamin A, DNA, and phospholipids.
6. Acts with selenium for the maintenance of cell membranes. This effect may be more neuronal.
7. Vitamin E plays a role in protecting the RBC membranes from oxidant stress.
8. There is evidence to prevent retrolental fibroplasia,  intraventricular hemorrhage, and mortality of premature infants.
9. Vitamin E may have a preventive role in cardiovascular disease.
10. Vitamin E also plays a role in neurological diseases.
11. It maintains healthy skin by preventing oxidative stress.

What is the presentation of  Vitamin E deficiency?

1. There is irritability and edema.
2. There is peripheral neuropathy and ataxia.
3. There is a degeneration of the spinal cord.
4. Vitamin E protects the RBC’s cell membrane from oxidants.
   1. The anemia is due to the fragile RBC membrane, and there is no response to iron therapy.
5. Mild Hemolytic anemia in infants.
6. These symptoms due to its deficiency are rare except for malabsorption.
7. There is a loss of tendon reflexes.
8. There may be pigmentary retinopathy.

What are the signs and symptoms of vitamin E deficiency?

1. The major symptom is mild hemolytic anemia.
2. A relationship exists between vitamin E  deficiency and progressive loss of neurological function in infants and children with chronic cholestasis.
3. Premature infants are supplemented with vitamin E to stabilize the RBC membranes and prevent hemolytic anemia.
4. It has been found that there is a relationship between vitamin E deficiency and the progressive loss of neurological signs in infants and children with chronic cholestasis.
5. The nervous system is very sensitive to vitamin E deficiency.
   1. Some signs of Vitamin E deficiency include axonal deterioration in the spinal cord, which is associated with gait disturbance and stability.
6. Sterility is found in animal models.
7. There is macrocytic megaloblastic anemia in α-Tocopherol deficiency.
8. How will you diagnose vitamin E deficiency?
   1. α-Tocopherol concentration is <5 mg/L.

What are the signs and symptoms of  Vitamin E toxicity?

1. There is decreased platelet aggregation.
2. There may be impaired wound healing.
3. There is impaired fibrinolysis.
4. There may be hepatomegaly.
5. There is creatinuria.
6. How will you Diagnose vitamin E toxicity?
   1. Infants receiving sufficient amounts of α-Tocopherol where serum level is >30 mg/L have an increased incidence of sepsis and necrotizing enterocolitis.
   2. The patients receiving a synthetic diet should be monitored to avoid Vitamin E toxicity.

What is the normal Vitamin E?

Source 1

1.  Some recommend > 0.5 mg / 100 ml.
2. Premature neonates  = 0.31 to ± 0.06 mg/dL.
3. 1 to 12 years = 0.3 to 0.9 mg/dL
4. 13 to 19 years = 0.6 to 1.0 mg/dL
5. Adult  = 0.5 to 1.8 mg/dL
6. Deficiency =  <0.3 mg/dL
7. Excess level  =  >4 mg/dL

Another source

• Recommended daily dose for adult males = 10 mg/day.
  • For females = 8 mg/day.

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