Abstract
In order to investigate the influence of vitamin B_2 deficiency on the lipid metabolism in skin and the effect of FAD, pyridoxal 5'-phosphate (PLP) and FAD+PLP supplementation during recovery in rats, skin surface lipids and composition of fatty acids in epidermis and liver of rats were estimated. Following results were obtained. 1. The total amounts of skin surface lipids were decreased in deficient rats. In the ratio of' each lipid fraction to the total lipids, neutral lipids were decreased, while total cholesterol was increased and squalene was increased remarkably. By supplying FAD or FAD+PLP to deficient rats, squalene ways decreased remarkably, but on neutral lipids and total cholesterol, these effects were not clear. 2. Vitamin B_2 deficiency decreased the percentage of C_<16:0>, C_<16:1> and C_<18:1>, and increased the percentage of C_<18:0>, C_<18:2> and C_<20:4> in fatty acid of epidermal lipids. Administration of FAD or FAD+PLP to viamin B_2 deficiency brought about improvement of the abnormal fatty acid composition. The administration of FAD+ PLP was more effective than it of FAD alone on the improvement of C_<20:4> Proportion. PLP was ineffective. 3. The ratio of C_<20:4> to C<18:2> in phospholipids elevated according to deficiency, which was not improved by FAD or PLP alone but was recovered by FAD+PLP.
