Effects of pre- and postnatal iron and n-3 fatty acid depletion, alone and in combination, on bone development in rats

Abstract

A third of women and a fifth of men over the age of 50 worldwide are estimated to endure an osteoporotic fracture (Svedbom et al., 2013), and 75% of hip fractures are predicted to occur in developing countries by 2050 (Genant et al., 1999). It is also believed that the prevalence is increasing as a result of an aging population in developed and developing countries (Woolf and Pfleger, 2005, Handa et al., 2008, Mushtaq et al., 2014). Iron and omega-3 (n-3) polyunsaturated fatty acids (PUFAs) are vital nutrients during early development and may also play an important role in bone development (Palacios, 2006, Claassen et al., 1995, Haag et al., 2003, Kruger and Schollum, 2005, Lau et al., 2013). The aim of this study was therefore to investigate the effects of pre- and postnatal iron and n-3 PUFA depletion, alone and in combination, on bone development in rats, and to determine whether effects are sex-specific. Female Wistar rats were randomly allocated to one of four diets: 1) Control, 2) iron deficiency (ID), 3) n-3 fatty acid deficiency (FAD) or 4) ID and n-3 FAD, and were maintained on the respective diets throughout pregnancy and lactation. Offspring continued on the respective diets after weaning until post-natal day 42-45, when bone mineral density (BMD) and bone strength were determined using dual X-ray absorptiometry and three-point bending tests, respectively. Results from this study showed that a pre- and post-natal ID has negative effects on the BMD and bone strength of offspring in early adolescence. A pre- and post-natal n-3 FAD might have an additive effect by further decreasing BMD and bone strength. Further research is needed to determine whether the effects of a pre- and post-natal ID on bone development in the offspring can be reversed if offspring is switched to a control diet after weaning, or if dams receive iron supplementation during pregnancy and lactation