Bone health of adult hemodialysis patients is related to vitamin K status

Kohlmeier, Martin; Saupe, Jörg; Shearer, Martin J.; Schaefer, K.; Asmus, G.

doi:10.1038/ki.1997.166

Cited by 95 publications

(59 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The physiological role of OC in bone metabolism has not yet been elucidated, but the level of ucOC is considered a sensitive measure of the vitamin K status of bone, and a high concentration of ucOC has been associated with a risk of hip fracture (16)(17)(18)(19). In this study, we examined the correlation between dietary vitamin K intake and vitamin K metabolism in healthy young males.…”

Section: Discussionmentioning

confidence: 99%

“…The amount of OC which is not carboxylated (undercarboxylated OC: ucOC) is considered a sensitive index of the vitamin K status of bone, and an elevated ratio of ucOC to intact OC is thought to be associated with low dietary intakes of vitamin K (12)(13)(14)(15). In previous studies, elevated ucOC has been associated with an increased risk of hip fracture in elderly people (16)(17)(18)(19) . In nature, vitamin K is found in two forms.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Nutritional Effects of .GAMMA.-Glutamyl Carboxylase Gene Polymorphism on the Correlation between the Vitamin K Status and .GAMMA.-Carboxylation of Osteocalcin in Young Males

Sogabe

Tsugawa

Maruyama

et al. 2007

J Nutr Sci Vitaminol

View full text Add to dashboard Cite

Summary Vitamin K is a cofactor for ␥ -glutamyl carboxylase (GGCX), which is an essential enzyme for the ␥ -carboxylation of vitamin K-dependent proteins such as osteocalcin (OC). Associations among dietary vitamin K intake, vitamin K status, and bone metabolism have not been thoroughly investigated. Recently, it has been reported that single nucleotide polymorphisms of GGCX (R325Q, 974G Ͼ A) were associated with age-related bone loss and the kinetic affinity for the substrate. In the present study, we investigated the associations among dietary vitamin K intake, the level of serum vitamin K, and the ratio of undercarboxylated OC (ucOC) to intact OC. The subjects were 60 healthy young male volunteers (mean age, 22.6 y; standard deviation, 1.6). Dietary nutrient intake was assessed by consecutive individual 3-d food records taken before the day of blood examinations. Serum concentrations of vitamin K (phylloquinone: PK, menaquinone 4: MK-4, and menaquinone 7: MK-7), ucOC, and intact OC were measured. All subjects were genotyped for polymorphism (R325Q) presence. Dietary vitamin K intake from vegetables was significantly correlated with the level of serum PK, and vitamin K intake from fermented beans, natto, was also significantly correlated with the level of serum MK-7. The ratio of ucOC to intact OC showed a negative association with the total vitamin K intake ( r ϭϪ 0.331, p ϭ 0.010) and serum MK-7 ( r ϭϪ 0.394, p ϭ 0.002). Interestingly, grouped by the GGCX genotype, a significant interaction between the ratio of ucOC to intact OC with serum MK-7 was observed in 325R homozygotes ( r ϭϪ 0.572, p ϭ 0.003), but not in heterozygotes, nor in 325Q homozygotes. This is the first report to suggest the effects of the single nucleotide polymorphism R325Q in the GGCX gene on the correlation between the level of serum MK-7 and ␥ -carboxylation of serum OC.

show abstract

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

Nutritional Effects of .GAMMA.-Glutamyl Carboxylase Gene Polymorphism on the Correlation between the Vitamin K Status and .GAMMA.-Carboxylation of Osteocalcin in Young Males

Sogabe

Tsugawa

Maruyama

et al. 2007

J Nutr Sci Vitaminol

View full text Add to dashboard Cite

show abstract

“…The apoE gene is polymorphic, with three common alleles resulting in six genotypes (E2/2, E2/3, E2/4, E3/3, E3/4 and E4/4) (Davignon et al, 1988). ApoE genotype has been linked to the TRL-mediated transport of phylloquinone to bone (Saupe et al, 1993;Kohlmeier et al, 1997) and to osteoporotic fracture risk (Kohlmeier et al, 1998;Cauley et al, 1999) and low BMD (Shiraki et al, 1997), although not all studies find associations between apoE genotype and BMD or fracture risk (Booth et al, 2000, Heikkinen et al, 2000.…”

Section: Introductionmentioning

confidence: 99%

Ethnic differences in osteocalcin γ-carboxylation, plasma phylloquinone (vitamin K1) and apolipoprotein E genotype

et al. 2004

View full text Add to dashboard Cite

Objective: To investigate plasma osteocalcin g-carboxylation and its relationship to plasma phylloquinone concentration and apolipoprotein E (apoE) genotype in women from three ethnic groups with differing osteoporotic fracture risk. Design and subjects: Fasted blood samples were collected from postmenopausal Gambian (n ¼ 50), British (n ¼ 31) and Chinese women (n ¼ 23), and 11 premenopausal women in each group from three cross-sectional studies. Results: After adjustment for total osteocalcin, plasma undercarboxylated osteocalcin (adjusted ucOC) was lowest in Chinese and highest in British women postmenopause (British vs Chinese 103% higher, Po0.0001; Gambian vs Chinese 66% higher, Po0.01). No differences were observed premenopause. Within each ethnic group, adjusted ucOC was similar pre-and postmenopause. Postmenopause, plasma phylloquinone was higher in Chinese women (1.0 ng/ml) than in British (0.31 ng/ml) and Gambian women (0.36 ng/ml) (Po0.0001). Premenopause, plasma phylloquinone was higher in Gambian and Chinese women (0.6 ng/ml) than in British women (0.3 ng/ml; P ¼ 0.01). Plasma phylloquinone and adjusted ucOC were inversely related in postmenopausal British women (R 2 ¼ 32.4%; P ¼ 0.0008). ApoE4 frequency was Gambian 32.6%, British 13.8% and Chinese 6%. A lower adjusted ucOC was associated with apoE2 genotype in British and Chinese women. Ethnic differences in adjusted ucOC persisted after adjustment for phylloquinone and apoE genotype. Conclusion: These preliminary data indicate suboptimal vitamin K status in postmenopausal British compared to Chinese and Gambian women. Ethnic differences in apoE genotype may also influence osteocalcin g-carboxylation status. The study highlights the need for larger epidemiological investigations of ethnic differences in vitamin K status and the possible implications to bone health. Sponsorship: This work was funded by the MRC.

show abstract

“…Vitamin K status may also be determined by variations in the genes involved in the transport or uptake of vitamin K into liver and bone (apolipoprotein E (apoE)) or those involved in the tissue-specific recycling of vitamin K (Vitamin K Epoxide Reductase (VKOR)). There are few studies evaluating the effect of variations within these two genes and vitamin K status in either the general population or in those with CKD (6,(11)(12)(13).…”

mentioning

confidence: 99%