Relationship between Serum β-Cryptoxanthin and Circulating Bone Metabolic Markers in Healthy Individuals with the Intake of Juice (Citrus unshiu) Containing β-Cryptoxanthin

The relationship between the serum β-cryptoxanthin concentration and circulating biochemical markers of bone metabolism in healthy individuals with the intake of juice prepared from Satsuma mandarin (Citrus unshiu MARC.) containing β-cryptoxanthin was investigated. Twenty volunteers (10 men and ten women) were divided into two groups of 10 volunteers (5 men and 5 women) each, and each group was sequentially given juice (192 ml) containing two different amounts of β-cryptoxanthin once a day for 56 days as follows: either regular juice with naturally occurring β-cryptoxanthin 802 μg/100 ml or reinforced juice containing β-cryptoxanthin 1500 μg/100 ml. γ-Carboxylated osteocalcin, which is a marker of bone formation, and bone tartrate-resistant acid phosphatase (TRAP), which is a marker of bone resorption, were assayed. The serum β-cryptoxanthin concentration was significantly increased with the intake of regular juice for 56 days. This increase was significantly enhanced by the intake of β-cryptoxanthin-reinforced juice. The intake of regular juice or of β-cryptoxanthin-reinforced juice for 56 days caused a significant increase in serum γ-carboxylated osteocalcin and a significant decrease in serum bone TRAP activity. A positive relationship between serum β-cryptoxanthin and circulating γ-carboxylated osteocalcin concentrations was found using the value obtained from all groups for before intake and with the intake of regular juice and β-cryptoxanthin-reinforced juice. A negative relationship between serum β-cryptoxanthin concentration and circulating TRAP activity was observed. This study shows that a relationship between serum β-cryptoxanthin and circulating bone metabolic markers is found in healthy individuals with the intake of juice containing β-cryptoxanthin.