title: Lifelong low-phylloquinone intake is associated with cognitive impairments in old rats.
abstract: In a previous report, we showed vitamin K to preferentially accumulate in brain regions rich in white matter and to positively correlate with certain sphingolipids. In rodents, pharmacological vitamin K deficiency has resulted in behavioral perturbations. To gain insight on the role of vitamin K status on brain function, we investigated learning abilities (Morris water maze), motor activity (open field), and anxiety (elevated plus maze) in distinct groups of 6-, 12-, and 20-mo-old female Sprague-Dawley rats that had been fed diets containing low (L; ~80 μg/kg diet), adequate (A; ~500 μg/kg diet), or high (H; ~2000 μg/kg diet) levels of phylloquinone (μg/kg diet; n = 9-12/diet) since weaning. In 20-mo-old rats, sphingolipids (cerebroside, sulfatide, sphingomyelin, ceramide, and gangliosides), phylloquinone, and menaquinone-4 were also assessed in cerebellum, midbrain, pons medulla, striatum, and hippocampus. Lifetime consumption of a low-vitamin K diet resulted in cognitive deficits in the 20-mo-old rats, with those in the L group having longer latencies than those in the H group (P < 0.05); this was associated with higher concentrations of ceramides in the hippocampus (P < 0.05) and lower gangliosides in the pons medulla and midbrain (P < 0.05). The low-vitamin K diet did not affect cognition at 6 and 12 mo of age, nor did it affect motor activity or anxiety at any age. Although much remains to be elucidated about the mechanism of action of vitamin K in cognition, this report points to vitamin K as an important nutritional factor contributing to cognitive health during aging.
authors.affiliation: Département de Nutrition, Université de Montréal, Montréal H3C 3J7, QC, Canada.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Carrié
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Bélanger
authors.forename: Jacques
authors.initials: J
authors.lastname: Portoukalian
authors.forename: Joseph
authors.initials: J
authors.lastname: Rochford
authors.forename: Guylaine
authors.initials: G
authors.lastname: Ferland
mesh_terms: D000818:Animals; D003072:Cognition Disorders / Q000378:metabolism* / Q000503:physiopathology; D005260:Female; D018782:Maze Learning; D051381:Rats; D017207:Rats, Sprague-Dawley; D013109:Sphingomyelins / Q000378:metabolism; D010837:Vitamin K 1 / Q000008:administration & dosage* / Q000378:metabolism
chemical_list: D013109:Sphingomyelins; D010837:Vitamin K 1