Author:
Habauzit Véronique,Nielsen Inge-Lise,Gil-Izquierdo Angel,Trzeciakiewicz Anna,Morand Christine,Chee Winnie,Barron Denis,Lebecque Patrice,Davicco Marie-Jeanne,Williamson Gary,Offord Elizabeth,Coxam Véronique,Horcajada Marie-Noëlle
Abstract
Hesperidin (Hp), a citrus flavonoid predominantly found in oranges, shows bone-sparing effects in ovariectomised (OVX) animals. In human subjects, the bioavailability of Hp can be improved by the removal of the rhamnose group to yield hesperetin-7-glucoside (H-7-glc). The aim of the present work was to test whether H-7-glc was more bioavailable and therefore more effective than Hp in the prevention of bone loss in the OVX rat. Adult 6-month-old female Wistar rats were sham operated or OVX, then pair fed for 90 d a casein-based diet supplemented or not with freeze-dried orange juice enriched with Hp or H-7-glc at two dose equivalents of the hesperetin aglycone (0·25 and 0·5 %). In the rats fed 0·5 %, a reduction in OVX-induced bone loss was observed regarding total bone mineral density (BMD):+7·0 % in OVX rats treated with Hp (HpOVX) and +6·6 % in OVX rats treated with H-7-glc (H-7-glcOVX)v.OVX controls (P < 0·05). In the rats fed 0·25 % hesperetin equivalents, the H-7-glcOVX group showed a 6·6 % improvement in total femoral BMDv.the OVX controls (P < 0·05), whereas the Hp diet had no effect at this dose. The BMD of rats fed 0·25 % H-7-glc was equal to that of those given 0·5 % Hp, but was not further increased at 0·5 % H-7-glc. Plasma hesperetin levels and relative urinary excretion were significantly enhanced in the H-7-glcv.Hp groups, and the metabolite profile showed the absence of eriodictyol metabolites and increased levels of hesperetin sulphates. Taken together, improved bioavailability of H-7-glc may explain the more efficient bone protection of this compound.
Publisher
Cambridge University Press (CUP)
Subject
Nutrition and Dietetics,Medicine (miscellaneous)