Oral Administration of .BETA.-Cryptoxanthin Induces Anabolic Effects on Bone Components in the Femoral Tissues of Rats in Vivo

Abstract

Bone loss with aging induces osteoporosis, which is widely recognized as a major public health problem.1-3) A decrease in bone mass leads to bone fracture. Bone loss may be due to decreased bone formation and increased bone resorption. Pharmacologic and nutritional factors are needed to prevent bone loss with increasing age. Chemical factors in food may help to prevent bone loss with aging.4) The chemical compounds in food which act on bone metabolism, however, are poorly understood.Recent studies have shown that isoflavones (increasing genistein and daidzein), which are contained in soybean, have a stimulatory effect on bone formation, [5][6][7][8] thereby increasing bone mass. 9) Also, menaquinone-7, an analogue of vitamin K 2 which is essential for the g-carboxylation of osteocalcin of bone matrix protein, is abundant in fermented soybean.10) Menaquinone-7 has been demonstrated to stimulate osteoblastic bone formation 11) and to inhibit osteoclastic bone resorption 12) in vitro. The supplementation of isoflavones and vitamin K 2 has a preventive effect on bone loss induced by ovariectomy in rats, which is an animal model of osteoporosis. [13][14][15][16] Food chemical factors thus play a role in bone health and may be important in the prevention of bone loss with increasing age.Carotenoids are present in fruit and vegetables. The effects of carotenoids on bone metabolism, however, have not yet been clarified. Recently, it has been shown that b-cryptoxanthin has a unique anabolic effect on bone calcification in vitro.17) Lutein, lycopene, and b-carotene do not have an effect on bone calcification in vitro. 17,18) b-Cryptoxanthin has a direct stimulatory effect on bone formation and an inhibitory effect on bone resorption in cultured in vitro. 18)The present study was undertaken to determine the effect of the administration of b-cryptoxanthin on bone components in growing rats in vivo. The oral administration of bcryptoxanthin, which was isolated from Satsuma mandarin, was found to induce anabolic effects on bone components in vivo. MATERIALS AND METHODSChemicals Dulbecco's modified Eagle's medium (DMEM) (high glucose, 4.5 g/dl) and a penicillin-streptomycin solution (5000 units/mg penicillin and 5000 mg/ml streptomycin) were obtained from Gibco Laboratories (Grand Island, NY, U.S.A.). Bovine serum albumin (BSA), cycloheximide, and corn oil were obtained from Sigma Chemical (St. Louis, MO, U.S.A.). b-Cryptoxanthin (100% purity) was supplied from Ehime Beverage Inc. (Matsuyama, Japan). All other chemicals were reagent grade from Wako Pure Chemical Industries (Osaka, Japan). All water used was glassdistilled.Animals Male Wistar rats (4 weeks old) were obtained from Japan SLC (Hamamatsu, Japan). The animals were fed commercial laboratory chow (solid) containing 57.4% Ca and 1.1% P for 7 d at room temperature of 25°C and had free access to distilled water.Bone Culture The femurs were removed aseptically after exsanguination and soaked in ice-cold 0.25 M sucrose solution. The femur was cleaned of soft tissue and mar...

.BETA.-Cryptoxanthin and Bone Metabolism: The Preventive Role in Osteoporosis

“…39) β-Cryptoxanthin (10, 25 or 50 µg/100 g body weight) was orally administered once daily for 7 days to young male rats. 39) The administration of β-cryptoxanthin (25 or 50 µg/100 g body weight) caused a significant increase in calcium content, alkaline phosphatase activity, and DNA contents in the femoral-diaphyseal and -metaphyseal tissues. Such an effect is also observed in the femoral tissues of aged (50-week-old) female rats.…”

The bone anabolic carotenoid β-cryptoxanthin enhances transforming growth factor-β1-induced SMAD activation in MC3T3 preosteoblasts

“…4B). Discussion ß-cryptoxanthin has been shown to have a stimulatory effect on osteoblastic bone formation in vitro (6,7) and in vivo (10)(11)(12) by stimulating osteoblastic cell proliferation and differentiation and by regulating osteoblastic gene expression, including Runx2 a master regulator of osteoblast differentiation (26,28), the matrix protein of ·1 (I) collagen (6,29), and alkaline phosphatase which participates in the mineralization process (6,30). The molecular mechanism by which ß-cryptoxanthin promotes osteoblast differentiation is, however, poorly defined.…”

“…), has anabolic effects on osteoblastic bone formation (4-7) and suppressive effects on osteoclastic bone resorption in vitro (5,8,9), leading to an increase in bone mass. Furthermore, oral administration of ß-cryptoxanthin was shown to have anabolic effects on bone turnover in young and aged rats (10), and prevents bone loss in streptozotocin-diabetic rats (11), and ovariectomized rats (12) in vivo.…”

Oral administration of β-cryptoxanthin prevents bone loss in ovariectomized rats

“…The oral administration of ß-cryptoxanthin has been shown to induce an anabolic effect on bone components in the femoral-diaphyseal (cortical bone) and -metaphyseal (trabecular bone) tissues in young and aged rats in vivo (13,14). Moreover, it has been found that streptozotocin-induced bone loss in rats with a diabetic state is prevented by the oral administration of ß-cryptoxanthin in vivo (15).…”