Effect of carotenoid on calcium content and alkaline phosphatase activity in rat femoral tissues in vitro: The unique anabolic effect of β-cryptoxanthin

Abstract

The effects of various carotenoids and rutin on calcium content and alkaline phosphatase activity in the femoral-diaphyseal and femoral-metaphyseal tissues of young rats in vitro were investigated. Bone tissues were cultured for 48 h in serum-free Dulbecco's modified Eagle's medium containing either vehicle or a compound (10-8-10-6 M). The presence of β-cryptoxanthin (10-7 or 10-6 M) caused a significant increase in calcium content and alkaline phosphatase activity in the femoral-diaphyseal and femoral-metaphyseal tissues. Also, the lowest concentration (10-8 M) of β-cryptoxanthin used caused a significant increase in diaphyseal and metaphyseal calcium content. Lutein (10-8-10-6 M) had no effect on diaphyseal and metaphyseal calcium contents and diaphyseal alkaline phosphatase activity, while 10 -7 and 10-6 M lutein significantly decreased metaphyseal alkaline phosphatase activity. Lycopene (10-8-10-6 M) or rutin (10-8-10-6 M) did not have a significant effect on bone calcium content and alkaline phosphatase activity. The present study suggests that the carotenoid β-cryptoxanthin has a unique anabolic effect on bone calcification in vitro.