Effects of Gamma-Glutamyl Carboxylase Gene Polymorphism (R325Q) on the Association between Dietary Vitamin K Intake and Gamma-Carboxylation of Osteocalcin in Young Adults

γ－麩胺醯羧化酶基因多型性（R325Q）對於年輕成人飲食中維生素K攝取和骨鈣素γ－羧化相關性之影響

Mayu Haraikawa ； Naoko Tsugawa ； Natsuko Sogabe ； Rieko Tanabe ； Yuka Kawamura ； Toshio Okano ； Takayuki Hosoi ； Masae Goseki-Sone

《Asia Pacific Journal of Clinical Nutrition》 22卷4期 (2013/11) Pp. 646-654

https://doi.org/10.6133/apjcn.2013.22.4.01

摘要

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 intake, 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 polymorphism, 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.

關鍵字

維生素K攝取 ； 維生素K1（PK） ； 維生素K2（MK-7） ； 單核苷酸多型性（SNP） ； γ－麩胺醯羧化酶（GGCX）

並列摘要

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 intake, 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 polymorphism, 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.

並列關鍵字

vitamin K intake ； phylloquinone (PK) ； menaquinone-7 (MK-7) ； single nucleotide polymorphisms (SNP) ； gamma-glutamyl carboxylase (GGCX)

參考文獻

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