Oral administration of beta-cryptoxanthin prevents bone loss in streptozotocin-diabetic rats in vivo.

The effects of beta-cryptoxanthin, a carotenoid, on bone components in the femoral-diaphyseal and -metaphyseal tissues of streptozotocin (STZ)-diabetic rats was investigated. Rats received a single subcutaneous administration of STZ (6.0 mg/100 g body weight), and then the animal were orally administered beta-cryptoxanthin (5 or 10 microg/100 g body weight) once daily for 7 or 14 d. The administration of STZ caused a significant decrease in body weight and a significant increase in serum glucose, triglyceride, and calcium levels, indicating a diabetic state. These alterations were significantly prevented by the administration of beta-cryptoxanthin (5 or 10 microg/100 g) for 14 d. The administration of beta-cryptoxanthin (5 or 10 microg/100 g) to normal rats for 14 d did not have a significant effect on body weight or on serum glucose, triglyceride, and calcium levels. Calcium content, alkaline phosphatase activity, and DNA content in the femoral-diaphyseal and -metaphyseal tissues were significantly decreased in STZ-diabetic rats. These decreases were significantly prevented by the administration of beta-cryptoxanthin (5 or 10 microg/100 g) for 14 d. The administration of beta-cryptoxanthin to normal rats for 14 d caused a significant increase in calcium content, alkaline phosphatase activity, and DNA content in the femoral-diaphyseal and -metaphyseal tissues. This study demonstrates that the intake of beta-cryptoxanthin has a preventive effect on bone loss in STZ-diabetic rats.