Effects of Mild and Severe Vitamin B Deficiencies on the Meiotic Maturation of Mice Oocytes

Abstract

We investigated the effects of vitamin B 1 deficiency on the meiosis maturation of oocytes. Female Crl:CD1 (ICR) mice were fed a 20% casein diet (control group) or a vitamin B 1 –free diet (test group). The vitamin B 1 concentration in ovary was approximately 30% lower in the test group than in the control group. Oocyte meiosis was not affected by vitamin B 1 deficiency when the deficiency was not accompanied by body weight loss. On the contrary, frequency of abnormal oocyte was increased by vitamin B 1 deficiency when deficiency was accompanied by body weight loss (referred to as severe vitamin B 1 deficiency; frequency of abnormal oocyte, 13.8% vs 43.7%, P = .0071). The frequency of abnormal oocytes was decreased by refeeding of a vitamin B 1 –containing diet (13.9% vs 22.9%, P = .503). These results suggest that severe vitamin B 1 deficiency inhibited meiotic maturation of oocytes but did not damage immature oocytes.