The effects of 5, 10, and 20% dietary xylitol supplementations on the biome
chanical properties, histological architecture, and the contents of collage
n, pyridinoline, and deoxypyridinoline in long bones of rats were studied.
Tibiae were used for the three-point bending test, and femurs were used for
the torsion and loading test of the femoral neck. The 10 and 20% oral xyli
tol administrations caused a significant increase of tibial stress, femoral
shear stress, and stress of the femoral neck as compared with the controls
. Parallel, but not significant, effects were also seen in the 5% xylitol s
upplementation group. No significant differences in strain or Young's modul
us of the tibiae were detected between the groups. An increased shear modul
us of elasticity in femurs was detected in the 20% supplementation group as
compared with the controls. The histomorphometrical data for the secondary
spongiosa of the proximal tibia revealed that trabecular bone volume was s
ignificantly greater in all dietary xylitol supplementation groups as compa
red with the controls. The bone volume increased along with increasing xyli
tol content. No significant differences between the groups were detected co
ncerning the amount of collagen per dry weight of organic matrix, the conce
ntrations of pyridinoline or deoxypyridinoline in collagen, or the ratio of
these crosslinks. This suggests no xylitol-dependent selective changes in
these structures of bone collagen. In conclusion, dietary xylitol supplemen
tation in rats improves the biomechanical properties of bone and increases
the trabecular bone volume dose dependently.