The Effects of Isoflavones Intake Level on Bone Markers and Bone Related Hormones in Growing Female Rats

ABSTRACT

The overall purpose of this study was to investigate the effects of level of isoflavones supplementation on bone metabolism in growing female rats. Forty-five rats divided into three groups; Control, 1/2IF, and 1IF. Serum osteocalcin and alkaline phosphatase (ALP) activity, urinary deoxypyridinoline (DPD) crosslinks value were measured to monitor bone formation and resorption at the ninth week after feeding. Hormones related to bone metabolism were determined, included parathyroid hormone (PTH), calcitonin, estradiol, growth hormone and insulin-like growth factor I (IGF-I). The results of this study were as follows: the isoflavones intake level did not affect weight gain, mean food intake and food efficiency ratio. The serum concentration of osteocalcin and the activity of ALP were not significantly different by different levels of isoflavones supplementation. The urinary DPD crosslinks value was not significantly different by different levels of isoflavones supplementation. There were no significant differences in serum PTH, estradiol and IGFI among all groups. However, calcitonin was shown significantly higher in the groups of 1IF and 1/2IF than control group. And growth hormone was shown significantly higher in the groups of 1IF than control group.