Effect of daidzein, a soy isoflavone, on bone metabolism in Cd-treated ovariectomized rats.
This study compared the ability of daidzein, a soy isoflavone, with that of 17beta-estradiol to prevent bone loss in cadmium (Cd)-exposed ovariectomized (OVX) rats during growth. Four week-old female Wistar rats were randomly assigned to five treatment groups of 9 rats each, either (1) sham-operated (SH); (2) OVX and placed on experimental diets (OVX); (3) OVX fed 50 ppm of CdCl2 (OVX-Cd); (4) OVX fed 50 ppm of CdCl2 and 10 microg of daidzein per kg of body mass (OVX-CD-D); or (5) OVX fed 50 ppm of CdCl2 and 10 microg of estrogen per kg of body mass (OVX-CD-E). All rats were given free access to AIN-76 modified diet and drinking water, with or without Cd, for 8 weeks. The OVX groups gained more (P < 0.05) body mass than the SH group. Femoral mass was increased by feeding daidzein and estradiol, whereas femoral length was not (P > 0.05) significantly different among groups. Femoral breaking force was not significantly different among groups, however, femoral BMD was significantly lower in OVX-Cd than in the SH and OVX groups. Morphologically proliferative cartilage and hypertrophic cells in femur showed normal distribution in OVX-Cd-D and OVX-Cd-E groups unlike those in OVX-Cd group. These findings suggest that Cd-OVX-induced osteopenia or osteoporosis probably results from an increase in bone turnover.
Om
Ae-Son
AS
Department of Food and Nutrition, College of Human Ecology, Hanyang University, Seoul, South Korea. aesonom@hanyang.ac.kr
Shim
Jae-Young
JY
D000818:Animals; D015519:Bone Density / Q000187:drug effects; D001842:Bone and Bones / Q000187:drug effects* / Q000378:metabolism; D002104:Cadmium / Q000633:toxicity; D002118:Calcium / Q000378:metabolism; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D005269:Femur / Q000187:drug effects / Q000378:metabolism; D007529:Isoflavones / Q000494:pharmacology*; D010052:Ovariectomy; D051381:Rats; D017208:Rats, Wistar; D013025:Glycine max / Q000737:chemistry*
D007529:Isoflavones; D002104:Cadmium; D004958:Estradiol; C004742:daidzein; D002118:Calcium