The importance of vitamin C for hydroxylation of vitamin D3 to 1,25(OH)2D3 in man.

The effects of vitamin C on 1,25(OH)2D3 synthesis in humans were evaluated; the study included 20 females. They were divided into 2 groups. The first of the 10 subjects (age range 55-71) received ascorbic acid at a dose of 150 mg/die i.

Mononuclear cells are not involved in BGP synthesis and secretion.

Osteocalcin or bone GLA protein (BGP) is found at high levels in only two tissues, the extracellular matrix of bone and dentine. Tissue culture experiments have demonstrated that BGP is synthesized by two osteoblastic osteosarcoma cell lines (ROS 2/3 and 17/2) and by normal osteoblastic cells in primary culture. BGP was not found in rat cartilage nor in liver, kidney, lung, spleen, brain, heart, thymus, skeletal muscle.

Evaluation of mineral metabolism and bone turnover in osteoporotic females treated with phosphorus and salmon calcitonin.

Twenty-five patients with radiological and clinical evidence of osteoporosis were studied. Nineteen patients received oral phosphorus at a dose of 1,000 mg/die for 10 days followed by salmon calcitonin (100 U MRC/die) for 20 days. Six patients received only oral calcium at a dose of 1,000 mg/die).