Maternal Vitamin B-12 In Mice Positively Regulates Bone, But Not Muscle Mass And Strength In Post-Weaning And Mature Offspring

Vitamin B-12 deficiency has been shown to affect bone mass in rodents and negatively impact bone formation in humans. In this study using mouse models, we define the effect of B-12 supplementation in the wild-type mother and B-12 deficiency in a mouse genetic model (Gif-/- mice) during gestation on bone and muscle architecture and mechanical properties in the offspring. Analysis of bones from 4-wk-old offspring of the wild-type mother following vehicle or B-12 supplementation during gestation (from embryonic day 0.5 to 20.5) showed an increase in bone mass caused by an isolated increase in bone formation in the B-12-supplemented group compared with vehicle controls. Analysis of the effect of B-12 deficiency in the mother in a mouse genetic model (Gif(-/-) mice) on the long bone architecture of the offspring showed a compromised cortical and trabecular bone mass, which was completely prevented by a single injection of B-12 in the B-12-deficient Gif(-/-) mothers. Biomechanical analysis of long bones of the offspring born from B-12-supplemented wild-type mothers showed an increase in bone strength, and conversely, offspring born from B-12-deficient Gif(-/-) mothers revealed a compromised bone strength, which could be rescued by a single injection of B-12 in the B-12-deficient Gif(-/-) mother. Muscle structure and function analysis however revealed no significant effect on muscle mass, structure, and grip strength of B-12 deficiency or supplementation in Gif(-/-) mice compared with littermate controls. Together, these results demonstrate the beneficial effect of maternally derived B-12 in the regulation of bone structure and function in the offspring.