Effect of 1alpha-hydroxyvitamin D3 and egg-shell calcium on bone metabolism in ovariectomized osteoporotic model rats.
Egg-shell calcium (Ca) is one of the effective Ca sources for bone metabolism. In the present study, we investigated whether egg-shell Ca had similar effects compared with calcium carbonate (CaCO3) when vitamin D3 (1alpha(OH)D3) treatment was given to an osteoporotic rat model. In both 1alpha(OH)D3-supplemented and -unsupplemented rats, the bone mineral density (BMD) of the lumber spine in the vitamin-supplemented group increased significantly compared with the unsupplemented group. In a Ca balance study, there were also significant differences in intestinal Ca absorption, urinary Ca and fecal Ca between the vitamin-supplemented and -unsupplemented groups. These results show that egg-shell Ca could have similar effects to CaCO3 on bone metabolism. In contrast with CaCO3, vitamin D3 supplementation did not significantly increase serum Ca levels in the egg-shell Ca group; however, the mechanism of Ca absorption is still unclear. Our results suggest that egg-shell Ca may be an effective nutrient in Ca metabolism for people treated with vitamin D3.
Department of Food and Nutrition, School of Home Economics, Japan Women's University, Tokyo.
T
T
Hirasawa
N
N
Omi
I
I
Ezawa
D000818:Animals; D015519:Bone Density; D001842:Bone and Bones / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism*; D019587:Dietary Supplements; D004195:Disease Models, Animal; D005260:Female; D005269:Femur / Q000378:metabolism; D006887:Hydroxycholecalciferols / Q000378:metabolism*; D008159:Lumbar Vertebrae / Q000378:metabolism; D010024:Osteoporosis / Q000378:metabolism*; D010052:Ovariectomy; D051381:Rats; D013977:Tibia / Q000378:metabolism
D006887:Hydroxycholecalciferols; D002118:Calcium; C008088:alfacalcidol