1. Multiple Dietary Vitamin K Forms Are Converted to Tissue Menaquinone-4 in Mice
- Author
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Joel B. Mason, Jessie L Ellis, Russell A. DeBose-Boyd, Xueyan Fu, Sarah L. Booth, Christopher J. Hernandez, and J. Philip Karl
- Subjects
Male ,medicine.medical_specialty ,Vitamin K ,Nutritional Status ,Medicine (miscellaneous) ,Adipose tissue ,Absorption (skin) ,High-performance liquid chromatography ,Dietary vitamin ,Mice ,chemistry.chemical_compound ,Internal medicine ,medicine ,Animals ,Kidney ,Nutrition and Dietetics ,Vitamin K 2 ,Vitamin K 1 ,Metabolism ,Naphthoquinone ,Diet ,Mice, Inbred C57BL ,medicine.anatomical_structure ,Endocrinology ,chemistry ,Female ,Nutrient Physiology, Metabolism, and Nutrient-Nutrient Interactions ,Analysis of variance - Abstract
BACKGROUND: Vitamin K is a term that comprises a family of structurally related quinones, phylloquinone (PK) and the menaquinones (MKn), that share a common naphthoquinone ring but vary in sidechain length (n) and saturation. Dietary PK is a biosynthetic precursor to tissue menaquinone-4 (MK4), but little is known about the absorption and metabolism of dietary MKn. OBJECTIVE: To characterize the absorption and metabolism of dietary MKn relative to PK. METHODS: In the 4-week diet study, 10-week-old male and female C57BL/6 mice were pair-fed a vitamin K deficient diet (control) or a diet supplemented with 5.0 μmol/kg total PK, MK4, and/or MK9 (separately and in combination). In the 1-week stable isotope study, 12-week-old mice were pair-fed diets containing 2.2 μmol/kg PK (unlabeled control), (2)H(7)PK, (13)C(11)MK4, (2)H(7)MK7, or (2)H(7)MK9. Vitamin K tissue content was quantified by HPLC and/or LC-MS, and concentrations were compared by sex and diet group using 2-factor ANOVA. RESULTS: Regardless of the form(s) of vitamin K provided in the diet, tissue MK4 concentrations did not differ across equimolar supplemented groups in the kidney, adipose, reproductive organ, bone, or pancreas in either males or females in the diet study (all P values > 0.05). Isotopic labeling confirmed the naphthoquinone ring of MK4 in tissues originated from the administered dietary PK or MKn. Despite equimolar supplementation, accumulation of the administered dietary form differed across diet groups in small intestinal segments (all P values
- Published
- 2022