INTRODUCTION: It has been demonstrated that single nucleotide polymorphism (SNP) (R325Q, 974G>A) in the gamma-glutamyl carboxylase (GGCX) gene is associated with the bone mineral density (BMD). In the present study, we investigated the effect of GGCX polymorphism (974G>A) on the correlations among the vitamin K in-take, level of serum vitamin K, and ratio of undercarboxylated osteocalcin (ucOC) to intact osteocalcin (OC) in healthy young Japanese subjects. METHODS: Healthy young adult subjects (n=189) were genotyped for the poly-morphism, and we measured the levels of serum vitamin K, intact OC, ucOC, and dietary nutrient intakes. RESULTS: Dietary vitamin K intake from vegetables was significantly correlated with the level of serum phylloquinone (PK), and vitamin K intake from fermented beans, natto, was also significantly correlated with the level of serum menaquinone-7 (MK-7). Moreover, the total dietary vitamin K intake showed a significant negative correlation with the ratio of ucOC to intact OC. Interestingly, on grouping by the GGCX genotype, there was a significant interaction between the ratio of ucOC to intact OC with vitamin K intake in homozygotes (GG-type) and heterozygotes (GA-type) (p<0.001). These results suggest that an adequate nutritional strategy is necessary for people with high-risk genotypes (GG- or GA-type). CONCLUSIONS: We demonstrated the effects of SNP (974G>A) in the GGCX gene on the correlation between dietary vitamin K intake and gamma-carboxylation of serum OC. Our data may be useful for planning strategies to prevent osteoporosis.
INTRODUCTION: It has been demonstrated that single nucleotide polymorphism (SNP) (R325Q, 974G>A) in the gamma-glutamyl carboxylase (GGCX) gene is associated with the bone mineral density (BMD). In the present study, we investigated the effect of GGCX polymorphism (974G>A) on the correlations among the vitamin K in-take, level of serum vitamin K, and ratio of undercarboxylated osteocalcin (ucOC) to intact osteocalcin (OC) in healthy young Japanese subjects. METHODS: Healthy young adult subjects (n=189) were genotyped for the poly-morphism, and we measured the levels of serum vitamin K, intact OC, ucOC, and dietary nutrient intakes. RESULTS: Dietary vitamin K intake from vegetables was significantly correlated with the level of serum phylloquinone (PK), and vitamin K intake from fermented beans, natto, was also significantly correlated with the level of serum menaquinone-7 (MK-7). Moreover, the total dietary vitamin K intake showed a significant negative correlation with the ratio of ucOC to intact OC. Interestingly, on grouping by the GGCX genotype, there was a significant interaction between the ratio of ucOC to intact OC with vitamin K intake in homozygotes (GG-type) and heterozygotes (GA-type) (p<0.001). These results suggest that an adequate nutritional strategy is necessary for people with high-risk genotypes (GG- or GA-type). CONCLUSIONS: We demonstrated the effects of SNP (974G>A) in the GGCX gene on the correlation between dietary vitamin K intake and gamma-carboxylation of serum OC. Our data may be useful for planning strategies to prevent osteoporosis.
Authors: Elizabeth Rendina-Ruedy; Kelsey D Hembree; Angela Sasaki; McKale R Davis; Stan A Lightfoot; Stephen L Clarke; Edralin A Lucas; Brenda J Smith Journal: J Nutr Metab Date: 2015-06-03
Authors: Sabine R Zwakenberg; Caren M Gundberg; Annemieke M W Spijkerman; Daphne L van der A; Yvonne T van der Schouw; Joline W J Beulens Journal: PLoS One Date: 2015-09-29 Impact factor: 3.240