Vitamin B6 Depletion in Man: Blood Vitamin B6, Plasma Pyridoxal-phosphate, Serum Cholesterol, Serum Transaminases and Urinary Vitamin B6 and 4-Pyridoxic Acid

Abstract
The effect of vitamin B6 depletion in man on several biochemical parameters was studied. Feeding a partially purified diet containing 0.16 mg vitamin B6 resulted in significant decreases in excretion of vitamin B6 and 4-pyridoxic acid, blood vitamin B6, plasma pyridoxal-phosphate and serum transaminase activities. After 5 days of depletion, blood vitamin B6 values were approximately 20% of pre-depletion values, and after 25 days of depletion there was a disappearance of blood vitamin B6 and of urinary 4-pyridoxic acid. Serum glutamic-pyruvic transaminase appeared to be affected more than serum glutamic-oxalacetic transaminase. Supplementation with 0.6 or 0.9 mg pyridoxine caused significant increases in most of the parameters which were affected by vitamin B6 depletion. Serum cholesterol concentration was not affected by the vitamin B6 intake.