Biochemistry-Vitamin B6 and its most important deficiency manifestations

Neurological, Dermatological and Hematological manifestations of B6 deficiency

Free online lectures especially for medical and dental students by the Biochemistry Club

• In Vitamin B₆ deficiency, the PLP dependent enzymes cannot function. 
• As a result there may the deficiency manifestations in the body.
• These manifestations may be :

1. Neurological
2. Dermatological
3. Hematological

1. Neurological manifestations

• Neurological symptoms are quite common in Vitamin B₆ deficiency.
• This is due to poor function of PLP dependent enzymes.
• As a result, serotonin, epinephrine, norepinephrine and GABA are not produced.
• In children Vitamin B₆ deficiency leads to convulsions die to decreased formation of GABA.
• PLP is also involved in the synthesis of sphingolipids; so deficiency of Vitamin B₆ leads to the demyelination of nerves resulting in peripheral neuritis.
• This can be reversed with high doses of Vitamin B₆.

2. Dermatological manifestions

• Tryptophan metabolism is also affected by Vitamin B₆ deficiency.
• As niacin is produced from tryptophan, the deficiency of Vitamin B₆ leads to niacin deficiency, manifested as Pellagra.

3. Hematological manifestations

• In Vitamin B₆ deficiency hypochromic microcytic anemia may occur due the inhibition of heme biosynthesis.
• Impaired antibody formation may also occur.
• Some metabolic disorders that respond to the Vitamin B₆ therapy are xanthurenic aciduria and homocystinuria.

For complete lesson on Vitamin B6, please click the Vitamins tab on home page in Biochemistry “I” tab or drop down menu. In Vitamins click the curriculum tab to view the whole list of lessons.