臨床栄養と代謝ジャーナル

Effects of Biotin Deficiency on the Urinary Excretion of B-Group Vitamins in Mice

Ai Tsuji* and Katsumi Shibata

Introduction: The eight kinds of B-group vitamins are involved with numerous metabolisms in harmony. Therefore, deprivation of one vitamin is likely to affect the pharmacokinetics and requirements of the other vitamins. Biotin has important roles, such as fatty acid synthesis, branched-chain amino acid catabolism, odd-chain fatty acid catabolism, and gluconeogenesis. We previously revealed that the urinary excretion rates of B-group vitamins decline when demand in the body increases. In the present study, we investigated the effects of biotin deficiency on the urinary excretion rates ((urinary excretion amount/intake amount) × 100) of other B-group vitamins.

Methods: ICR female mice were fed a 30% egg white diet with or without biotin. After feeding for 21 days, 24h urine samples were collected, and B-group vitamins were measured.

Results and conclusion: The urinary excretion rate of vitamin B₁ was markedly lower in the biotin-deficient mice than in the control mice. These results suggest that biotin deficiency increased the requirement of vitamin B₁ but did not affect the other six B-group vitamins.