Effect of β-Crytoxanthin on Circulating Bone Metabolic Markers : Intake of Juice (Citrus Unshiu) Supplemented with β-Cryptoxanthin Has an Effect in Menopausal Women

The effects of prolonged intake of juice prepared from Satsuma mandarin (Citrus unshiu MARC.) containing β-cryptoxanthin on circulating biochemical markers of bone metabolism in subjects, including menopausal woman, were investigated. Ninety volunteers, aged 27-65 years (19 men and 71 women), were enrolled in this study. The 71 females included 35 premenopausal women (ages, 27-50 years) and 36 postmenopausal women (ages, 46-65 years). Volunteers were divided into four groups; placebo juice without β-cyptoxanthin (5 men and 19 women), juice containing β-cyptoxanthin at 1.5mg/200ml of juice/day (4 men and 17 women), 3.0mg/day (5 men and 17 women), and 6.0mg/day (5 men and 18 women). Placebo orjuice (200ml) was ingested once a day for 28 or 56 days. Serum β-cryptoxanthin concentrations were significantly increased after the intake of juice containing β-cryptoxanthin (1.5, 3.0, or 6.0mg/day) for 28 or 56 days, and the increases were dose-dependent. Bone-specific alkaline phosphatase and γ-carboxylated osteocalcin are serum bone markers of bone formation, and bone tartrate-resistant acid phosphatase (TRACP) and N-telopeptides of type I collagen are markers of bone resorption. Bone-specific alkaline phosphatase activity was significantly increased after the intake of juice containing β-cryptoxanthin (3.0 or 6.0mg/day) for 56 days as compared with the value obtained before intake. γ-Carboxylated osteocalcin concentration was significantly increased after the intake of juice containing β-cryptoxanthin (3.0 or 6.0mg/day) for 28 or 56 days as compared with the value obtained before intake or after the intake of placebo juice. Serum TRACP activity and type I collagen N-telopeptide concentration were significantly decreased after the intake of juice containing β-cryptoxanthin (3.0 or 6.0mg/day) for 28 or 56 days as compared with the value obtained before intake or after intake of placebo juice, and significant decreases were also seen after the intake of 1.5mg/day β-cryptoxanthin as compared with the value obtained before intake. In menopausal women, bone-specific alkaline phosphatase activity and γ-carboxylated osteocalcin concentration were significantly increased after the intake of juice containing β-cryptoxanthin (3.0 or 6.0mg/day) for 56 days as compared with the value obtained after placebo intake. Also, this intake caused a significant decrease in bone TRACP activity. Meanwhile, serum calcium, inorganic phosphorous, and parathyroid hormone (intact) were not changed after the intake of β-cryptoxanthin-containing juice for 28 or 56 days. This study demonstrates that the prolonged intake of juice fortified with β-cryptoxanthin has stimulatory effects on bone formation and inhibitory effects on bone resorption in humans, and that the intake has an effect in menopausal women.