Ingestion of difructose anhydride III, a non-digestible disaccharide, improves postgastrectomy osteopenia in rats

Abstract

Objective. Total gastrectomy produces osteopenia with calcium malabsorption. We previously demonstrated that difructose anhydride III (DFAIII), a non-digestible disaccharide, stimulates intestinal calcium absorption in normal and ovariectomized rats. In the present study, we examined the effects of feeding DFAIII on gastrectomy-induced calcium malabsorption and osteopenia in rats. The potential of DFAIII to promote large intestinal calcium absorption was also evaluated through comparison with that of fructooligosaccharides (FOS). Material and methods. Male Sprague-Dawley rats were divided into two groups: totally gastrectomized and sham-operated rats. After a postoperative recovery period, rats from each group were divided into three subgroups and fed the control, DFAIII (30 g/kg), or FOS (30 g/kg) diet for 28 days. Results. Total gastrectomy severely reduced net calcium absorption, femoral calcium content and bone mineral density, resulting in fragility of the femur. DFAIII or FOS feeding partly and similarly restored the lowered calcium absorption and femoral variables, with an increase in the total short-chain fatty acid pool in the cecum. In gastrectomized rats, net calcium absorption was correlated with several cecal parameters, suggesting that cecal fermentation of DFAIII is associated with the improvement in gastrectomy-induced calcium malabsorption. Urinary excretion of deoxypyridinoline (D-Pyr) as a marker of bone resorption was increased by gastrectomy, and the elevated D-Pyr excretion was suppressed by feeding DFAIII. Conclusions. Supplemental feeding of DFAIII partly prevents postgastrectomy osteopenia as a result of an improvement in calcium absorption. Our results suggest that the promotive effects of DFAIII on calcium absorption in the large intestine are comparable to those of FOS.