Bone, metabolism mineralization

Studies in rats have shown effects of lead on bone mineralization and bone growth. The effects observed in rats may be relevant to our understanding of the mechanisms for the growth deficits that have been associated with low-level in utero and childhood lead exposures. Additional studies of the effects of lead on bone metabolism in humans and in animal models would improve our understanding of the toxicological significance of lead in bone. 

Liu J, Zhu H, Huang Q, Zhang Z, Li H, Qin Y, Zhang Y, Wei D, Lu J, Liu H, Xen X, Liu Y, Ekangaki A, Zheng Y, Diez-Perez A, Harper K (2004) Effects of raloxifene hydrochloride on bone mineral density, bone metabolism and serum lipids in Chinese postmenopausal women with osteoporosis a multi-center, randomized, placebo-controlled clinical trial. Chin Med J 117 1029-1035 (in English)... 

Dawson-Hughes, B. (2006a). Calcium and vitamin D. In "Primer on the Metabolic Bone Diseases and Disorders of Mineral Metabolism" (M. J. Favus, ed.), pp. 257-259. The American Society for Bone and Mineral Research, Washington DC. 

Studies of the effects of inhaled glucocorticoids have used biochemical markers of bone function and imaging techniques to assess bone mineral density. Some of the biochemical markers are summarized in Table 1. Initial, short-term studies caused concern about the effect of inhaled glucocorticoids on bone metabolism. 

While biochemical markers of bone metabolism may be sensitive to the effects of glucocorticoids in the short term, the relation between changes in these markers and intermediate measures, such as bone mineral density, and the more important clinical outcomes of fractures, is unknown. In a random stratified sample of 3222 women in the perimenopausal age range (47-56 years), including 119 women with asthma, bone mineral density was measured to determine whether asthma was a risk factor of osteoporosis and to investigate the effect of inhaled glucocorticoids (102). The subjects had predominantly adult-onset asthma, as the age at diagnosis was over 40 years. There were 26 patients who were treated mainly with... 

The use of gonadorelin analogues is commonly associated with reduced bone mineral density. In 50 premenopausal women with uterine leiomyomas who received leuprolide acetate depot 3.75 mg every 28 days for 18 cycles with raloxifene 60 mg/day, there was a reduction in leiomyoma size with no significant change in bone mineral density or markers of bone metabolism [86],... 

Ten patients who had taken lithium for less than 1 year and 13 who had taken it for more than 3 years were assessed for alterations in bone metabolism and parathyroid function (654). There were no differences in bone mineral density, serum calcium concentration, or PTH concentration, but both groups had increased bone turnover and the longterm group had nonsignificantly higher calcium and PTH concentrations (including one hyperparathyroid patient who had an adenoma excised). The authors conclusion that lithium therapy is not a risk factor for osteoporosis needs to be tempered by the small sample size, the case of adenoma, and the blood concentration trends. 

Hillman, L.S., Chow, W., Salmons, S.S., Weaver, E., Erickson, M., Hansen, J. 1988. Vitamin D metabolism, mineral homeostasis, and bone mineralization in term infants fed human milk, cow milk-based formula, or soy-based formula. J. Fed. 112, 864-874. 

Jergas M, Genant HK Radiologic imaging of metabolic bone disease, in Coe FL, Favus MJ (eds) Disorders of Bone and Mineral Metabolism. Lippincott Williams and Williams, Philadelphia, 2002, pp. 428-447. 

Calcitonin is a 32-amino-acid polypeptide hormone that was hrst purihed in 1962 by Copp and Cheney (121). It was originally thought as a product from parathyroid glands, but later it was discovered to be made by the C cells of the thyroid gland. Calcitonin participates in calcium and phosphorus metabolism, lowers plasma calcium and phosphate levels, and it has been used as a drug for bone and mineral disorders for a long time. 

While biochemical markers of bone metabolism may be sensitive to the effects of glucocorticoids in the short term, the relation between changes in these markers and intermediate measures, such as bone mineral density, and... 

Cole DEC, Carpenter TO, Goltzman D. Calcium homeostasis and disorders of bone and mineral metabolism. In CoUu R, Ducharna JR, Guyda HJ, editors. Pediatric Endocrinology. 2nd ed. New York Raven Press, 1989 509-80. 

Aoshima K, Iwata K, Kasuya M. Environmental exposure to cadmium and effects on human health. Part 2. Bone and mineral metabolism In inhabitants of the cadmium-polluted JInzu River basin In Toyama Prefecture. Jpn J Hyg (In Japanese) 1988 43 864-871. 

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