[Riboflavin metabolism in diabetes mellitus]

Riboflavin excretion with urine in children suffering from diabetes mellitus is found to be significantly higher in comparison with healthy adults, the riboflavin content in the serum being normal. The total riboflavin concentration in erythrocytes is substantially lower and administration of daily-required riboflavin doses does not increase this parameter. FAD-dependent glutathione reductase in erythrocyte hemolysates is approximately 1.5 times higher than that of healthy children and does not depend on the additional intake of polyvitamins. The seeming affinity of the enzyme with exogenous FAD in sick children is almost 40 times lower in comparison with this value in healthy children, that is why the FAD-effect value in diabetes mellitus children does not exceed 1.2. Peculiarities of the riboflavin metabolism at diabetes mellitus and possibility to use the investigated parameters as criteria of vitamin B2 supply are discussed.