Dietaryn-6:n-3 fatty acid ratio in the perinatal period affects bone parameters in adult female rats

Abstract

PUFA and their metabolites are important regulators of bone formation and resorption. The effect of PUFA on bone growth may be especially striking during the perinatal period. The aim of the present study was to investigate the effect of diets with differentn-6:n-3 fatty acid (FA) ratios during the perinatal period on bone parameters in the adult offspring. During late gestation and throughout lactation, rat dams were fed an isoenergetic diet containing 70 g linseed oil (n-3 diet), soyabean oil (n-6+n-3 diet) or sunflower-seed oil (n-6 diet) per kg withn-6:n-3 FA ratios of 0·4, 9 and 216, respectively. The offspring were weaned onto an ordinary chow and followed until 30 weeks of age. Bone parameters were analysed using peripheral quantitative computerised tomography and dual-energy X-ray absorptiometry. Femur length and cortical cross-sectional bone area and bone mineral content were significantly higher in then-6+n-3 group than in the other groups. Cortical bone thickness in then-6+n-3 group was increased compared with then-3 group, but most cortical bone parameters did not differ between then-3 andn-6 groups. The results suggest that regulatory mechanisms were influenced by then-6:n-3 FA ratio early in life and not compensated for by the introduction of an ordinary diet after weaning.