QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Harrington, D. J. Articles by Shearer, M. J. Search for Related Content PubMed PubMed Citation Articles by Harrington, D. J. Articles by Shearer, M. J.

---

Nutrient Physiology, Metabolism, and Nutrient-Nutrient Interactions

Excretion of the Urinary 5C- and 7C-Aglycone Metabolites of Vitamin K by Young Adults Responds to Changes in Dietary Phylloquinone and Dihydrophylloquinone Intakes^1,2

³ The Centre for Haemostasis and Thrombosis, St. Thomas' Hospital, London SE1 7EH, UK and ⁴ Jean Mayer US Department of Agriculture, Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111

^* To whom correspondence should be addressed. E-mail: domonic.harrington{at}gstt.nhs.uk.

The physiological function and putative health roles of vitamin K-dependent proteins now extend beyond their classical role in hemostasis and include bone mineralization, arterial calcification, apoptosis, phagocytosis, growth control, chemotaxis, and signal transduction. Current assessments of vitamin K status do not reflect the variety of molecular forms of vitamin K. We assessed whether urinary excretion of 2-methyl-3-(5'-carboxy-3'-methyl-2'-pentenyl)-1,4-naphthoquinone (7C-aglycone) and 2-methyl-3-(3'-3'-carboxymethylpropyl)-1,4-naphthoquinone (5C-aglycone), vitamin K metabolites common to both phylloquinone and the menaquinone series, reflect dietary vitamin K intake. In a randomized crossover study, 9 adults resided in a metabolic unit for two 30-d periods separated by a free-living period of 4 wk. During each residency, subjects consumed 3 sequential diets: a control diet (93 µg phylloquinone/d) for 5 d, a phylloquinone-restricted diet (11 µg/d) for 15 d, followed by a randomly assigned repletion diet for 10 d with either phylloquinone (206 µg/d) or dihydrophylloquinone (240 µg/d). During the second residency, the alternative repletion diet was assigned. Urinary excretion of the 5C- and 7C-aglycones was measured in sequential 24-h collections. The 5C-aglycone accounted for 75% of total excretion and declined in response to phylloquinone restriction (P = 0.001) to 30% of that during the control diet period. Repletion with phylloquinone and dihydrophylloquinone doubled the excretion rate of the major 5C-aglycone by 24 h (P < 0.001), and tripled excretion by 4 d. There was a linear relationship between the logarithm of total urinary excretion and dietary vitamin K intake (r = 0.699, P < 0.001). We conclude that the urinary excretion of vitamin K metabolites reflects dietary phylloquinone intake and offers the first candidate marker of global vitamin K status.

This article has been cited by other articles:

				S. L. Booth, J. W. Peterson, D. Smith, M. K. Shea, J. Chamberland, and N. Crivello Age and Dietary Form of Vitamin K Affect Menaquinone-4 Concentrations in Male Fischer 344 Rats J. Nutr., March 1, 2008; 138(3): 492 - 496. [Abstract] [Full Text] [PDF]