Abstract:

BACKGROUND: High fat diet (HFD) can induce overweight and obesity, which have been considered to positively affect bone mineral density (BMD) in adults. However, it is unclear how HFD affects the bone development during childhood.
OBJECTIVE: To determine the effect of HFD on bone development in young female mice.
METHODS: Twelve female CD1 mice were fed with either HFD or normal fat diet (NFD) starting at 4-week of age for 10 weeks. The bone mineral content (BMC), BMD, fat and lean mass were examined in 14-week old mice using dual-energy X-ray absorptiometry, and bone biomechanical properties were also evaluated using three-point bending test. Serum concentration of bone metabolic markers was measured using enzyme immunoassay. Femora were sectioned in the transverse plane and stained with hematoxylin and eosin for observing the adiposity of bone marrow and changes in trabecular bone area.
RESULTS AND CONCLUSION: The body weight and fat mass in HFD-treated mice were increased compared with those in NFD-treated mice, respectively. There were no significant differences between HFD-treated and NFD-treated mice in whole body BMD, BMC, bone area and lean mass. However, the spine BMC and bone area in HFD mice were significantly lower than that in NFD mice, while femoral BMD, BMC and bone area in HFD mice were significantly greater than that in NFD mice. But, there was no statistically different in bone biomechanical values between the two groups. Bone metabolic markers were lower in HFD mice than NFD mice, indicating the less active of bone metabolism in HFD mice. It is suggested that HFD can produce deleterious effect on bone during the active growing phase of young mice. Vertebral bone is more sensitive to this negative effect than cortical bone due to the decreased vertebral mineralization. Weight-bearing bone does not response sufficiently to compensate for the excessive weight gaining.