title: Vertebrae of developing fat-1 mice have greater strength and lower n-6/n-3 fatty acid ratio.
abstract: Incorporation of dietary n-3 polyunsaturated fatty acids (PUFA) into bone may optimize bone development. The study objective was to use the fat-1 mouse, a transgenic model that synthesizes n-3 PUFA from n-6 PUFA, to determine if bone mineral density (BMD) and biomechanical bone strength were favourably modulated by lowering the n-6/n-3 PUFA ratio in vertebrae. Male and female wild-type and fat-1 mice were fed an AIN93-G diet containing 10% safflower oil from weaning through 12 weeks of age. Vertebrae BMD was determined by dual energy x-ray absorptiometry and peak load, a surrogate measure of fracture risk, was measured by a materials testing system. Vertebrae fatty acid composition was measured by gas liquid chromatography. At 12 weeks of age, vertebrae peak load was higher in fat-1 mice compared to wild-type (P = 0.026). Fat-1 mice also had lower n-6/n-3 PUFA ratio in vertebrae than wild-type (P < 0.001) and this ratio was negatively correlated with BMD and peak load (P = 0.005). Moreover, n-3 PUFA including alpha-linolenic acid, eicosapentaenoic acid and docosahexaenoic acid were positively correlated (P < 0.05) with BMD and peak load. Therefore, a lower vertebrae n-6/n-3 PUFA ratio is associated with stronger vertebrae and suggests a positive role for n-3 PUFA in bone development.
authors.affiliation: Department Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada N1G 2W1.
authors.forename: Beatrice Y Y
authors.initials: BY
authors.lastname: Lau
authors.forename: Wendy E
authors.initials: WE
authors.lastname: Ward
authors.forename: Jing X
authors.initials: JX
authors.lastname: Kang
authors.forename: David W L
authors.initials: DW
authors.lastname: Ma
mesh_terms: D000818:Animals; D015519:Bone Density; D001846:Bone Development; D004032:Diet; D015525:Fatty Acids, Omega-3 / Q000235:genetics / Q000378:metabolism*; D043371:Fatty Acids, Omega-6 / Q000235:genetics / Q000378:metabolism*; D005260:Female; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D011859:Radiography; D013131:Spine / Q000000981:diagnostic imaging / Q000378:metabolism*
chemical_list: D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6