Plasma
vitamin E levels were found to be decreased (less than 0.5 mg) in
thalassemia and in 17 out of 20 patients with
Gaucher's disease, where the levels were two standard deviations below the normal mean value. In the latter, the decrease in
vitamin E levels correlated with the severity of the clinical expression of the disease and correlated inversely with the degree of hepatosplenomegaly and serum
tartrate-resistant acid phosphatase activity. In both diseases, there was no evidence for intestinal malabsorption of the
lipid-soluble
vitamin. In spite of the different etiology, pathophysiology, and clinical expression, severe
vitamin E deficiency could result in both diseases by a common mechanism. In
thalassemia, rapid consumption of
vitamin E occurs while neutralizing oxidative damage in the pathological erythrocyte membranes and in other tissues. In
Gaucher's disease, lysosomal accumulation of
glucocerebroside may stimulate phagocytes into a maintained "respiratory burst" with excessive production of
oxygen free radicals, resulting in increased utilization and eventual deficiency of
vitamin E. Efficacy of
antioxidant therapy was evaluated by administration of
vitamin E with and without
canthaxanthin, which has similar
antioxidant properties to
beta-carotene, to patients with
beta-thalassemia. The results showed increased serum
vitamin E levels and a decrease in the extent of erythrocyte
lipid membrane peroxidation, while no significant changes occurred in
hemoglobin levels and in transfusion requirements.