Effects of [beta]-cryptoxanthin on bone-formation parameters in the distal femoral epiphysis of ovariectomized mice

To compare the effects of [beta]-cryptoxanthin ([beta]-cry) from citrus fruit on bone-formation parameters in the distal femoral epiphysis of ovariectomized (OVX) mice with the effects of osteoporosis therapeutic agents. Ten-week-old OVX ICR mice were used. The mice were divided into five experimental groups: [beta]-cry; bisphosphonate (treatment with the bone resorption inhibitor risedronate); vitamin K^sub 2^ [treatment with the bone formation stimulator and bone resorption inhibitor menaquinone 4 (MK4)]; OVX control; and sham (no OVX). Risedronate was used as the bisphosphonate (risedronate group), and menaquinone 4 was used as vitamin K^sub 2^ (MK4 group). Risedronate was administered orally, and [beta]-cry and MK4 were mixed with the regular feed. The mice were fed the diets for 2 months. Femurs were resected, and blood samples were collected. Bone mineral density (BMD) was analyzed by peripheral quantitative computed tomography. Microcomputed tomography was also performed to evaluate the three-dimensional structure of the trabecular bone. In contrast to the risedronate and MK4 groups, there was no improvement in the trabecular BMD, cortical thickness, or periosteal perimeter in the [beta]-cry group. Trabecular structural parameters including the morphometric indices, continuity index, and connectivity index were significantly improved in the [beta]-cry group compared with the OVX control group. In particular, there was a marked improvement in morphometric indices. [beta]-Cry improved the trabecular structure. This suggests that [beta]-cry might be useful as a dietary supplement to prevent bone degeneration and osteoporosis associated with aging.[PUBLICATION ABSTRACT]