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Folate deficiency anemia

Folate deficiency anemia

- Folic acid is present in all food staffs but readily destroyed by 10-15 minutes of cooking. Thus fresh fruits and vegetables are good source of folates. Food folates are mostly in polyglutamate form and must be split into monoglutamate for absorption. Acidic foods and beans and other legumes block the intestinal absorption by inhibiting the enzyme that catalase the polyglutamate into monoglutamate. Pheytoin also inhibit folate absorption.

- The absorption of the folate occurs in the upper third of the intestine. thus malabsorption affecting this site produces folate deficiency.

- The folate is transported in the blood as monoglutamate form and within the cells it is mainly reduced into tetrahydrofolate by an enzyme, a reductase. This reductase is sensitive to inhibition by folate analogues such as methotrexate. The action of this enzyme deprives the cells of folates and hence the capacity to rapidly divide, a property that is the basis for the use of folate antigonists as anticancer agents.

- The tetrahydrofolate acts as an acceptor and donor of one-carbon unit in a variety of steps involved in the synthesis of purines and thymidylate, the DNA building blocks.

- The clinical picture is characterized by fatigue, weakness and symptoms referable to disturbance rapid cell turnover tissues like GI tract and hematopoietic system. There is no neurological abnormalities as in vitamin B12 deficiency.

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