Submitted to: Federation of American Societies for Experimental Biology Conference
Publication Type: Abstract Only
Publication Acceptance Date: 4/6/1997
Publication Date: N/A
Technical Abstract: Because perturbations in vitamin D and magnesium metabolism sometimes manifest concurrently with various types of osteoporosis, and because dietary boron modulates vitamin D and magnesium metabolism, the influence of boron on trabecular bone morphology during vitamin D and magnesium deficiency was examined. Weanling male rats (12 per group) were fed a ground corn, high protein casein, and corn oil based diet (~0.1 g B/kg; vitamin D-deficient) supplemented with boron at 0 or 2.0 mg/kg for 35 d, magnesium at 100 or 400 (adequate) mg/kg for 35 d, and 1000 IU vitamin D3/kg (NRC recommendation) for d 0 to 35 or d 16 to 35 (rehabilitation). In the proximal tibia, cut longitudinally in the midline and treated to remove all cellular material, an interaction among vitamin D rehabilitation, boron, and magnesium affected trabecular bone spicule surface area (p < 0.04) and the total trabecular bone area (spicules plus adjacent bone marrow spaces) (p <0.002). For example, over-abundance of trabecular bone induced by vitamin D rehabilitation (during adequate Mg intake) was corrected by boron. Under-development of trabecular bone induced by magnesium deficiency (during continuous vitamin D intake) was substantially improved by boron. The dietary treatments did not affect the width of trabecular bone spicules because the ratio between spicule surface area and total trabecular bone area did not differ among dietary groups. The findings suggest that boron is important in maintaining the normal architecture of trabecular bone when dietary vitamin D or magnesium are inadequate.