Mechanical assessment of effects of grape seed proanthocyanidins extract on tibial bone diaphysis in rats

Abstract We studied the effects of grape seed proanthocyanidins extract (GSPE) given as a ratio of 3 mg in 100 g in a standard diet,on the tibial bone diaphysis in low-calcium fed rats. Measurements of bone density, mineral content, geometry, and bonestrength using peripheral quantitative computed tomography (pQCT). Further, the whole tibia bones were tested for mechan-ical resistance using a material-testing machine, and mineral elements were also determined. Forty male Wistar rats, 5 weeksold, were divided into control (Co), low-calcium diet (LC), low-calcium diet O standard diet (LCS), and low-calcium diet O stan-dard diet with supplementary GSPE (LCSG) groups. We found no significant differences in body weight among the 4 groups,whereas all of the bone parameters in LC were significantly lower than those in Co (p<0.01, except in periosteal perimeter(Peri) p<0.05). The cortical bone mineral content (CtBMC), cortical bone density (CtvBMD) and Peri in LCSG were signif-icantly higher than those in LCS (p<0.01; p<0.01; p<0.05, respectively). All bone parameters in LCSG were significantlyhigher than those in LC (p<0.01, except in Peri, and stress strain index to reference axis x (xSSI) p<0.05). In addition, Ca, P,and Zn contents in LCSG were significantly higher than those in LCS (p<0.01; p<0.01; p<0.05, respectively). Our results sug-gest that GSPE included in a diet mixture with calcium has a beneficial effect on bone formation and bone strength for thetreatment of bone debility caused by a low level of calcium.