Osteoporosis has become a major health problem as the life expectancy of the general population has risen rapidly in recent years. Post-menopausal women are at greater risk because of accelerated bone loss induced by estrogen deficiency superimposed on age related bone loss. One of the important etiological factors in postmenopausal osteoporosis is the interaction between estrogen and PTH. PTH is known to be an important initiator of bone remodeling and persistent elevation of PTH, such as in hyperparathyroidism, presents as a risk factor for the development of osteoporosis. However, intermittent administration of PTH has been shown to be a promising regimen for improve bone mass in both the animals and humans. The dichotomy of this issue is not fully understood, especially in the estrogen deficient population. This project attempts to understand further the dualistic role of PTH as a catabolic and anabolic hormone in animal models of estrogen deficiency. The proposed study will have the following specific aims.
Specific Aim 1. To differentiate the anabolic action of continuous elevation of PTH from its catabolic action.
Specific Aim 2. To demonstrate the interactions of dietary calcium intakes with continuous and intermittent PTH administration under estrogen deficiency state, and Specific Aim 3. To study the interactions of PTH, cytokines and anti-resorptive agents at both tissue and subcellular levels in a mouse model of estrogen deficiency.

Project Start
1998-09-23
Project End
1999-08-31
Budget Start
1997-10-01
Budget End
1998-09-30
Support Year
11
Fiscal Year
1998
Total Cost
Indirect Cost
Name
Helen Hayes Hospital
Department
Type
DUNS #
157119244
City
Menands
State
NY
Country
United States
Zip Code
12204
Ascenzi, Maria-Grazia; Liao, Vivian P; Lee, Brittany M et al. (2012) Parathyroid hormone treatment improves the cortical bone microstructure by improving the distribution of type I collagen in postmenopausal women with osteoporosis. J Bone Miner Res 27:702-12
Zhang, Hao; Doty, Stephen B; Hughes, Christine et al. (2007) Increased resorptive activity and accompanying morphological alterations in osteoclasts derived from the oim/oim mouse model of osteogenesis imperfecta. J Cell Biochem 102:1011-20
Dempster, David W; Hughes-Begos, Christine E; Plavetic-Chee, Katarina et al. (2005) Normal human osteoclasts formed from peripheral blood monocytes express PTH type 1 receptors and are stimulated by PTH in the absence of osteoblasts. J Cell Biochem 95:139-48
Cosman, Felicia; Nieves, Jeri; Zion, Marsha et al. (2005) Daily and cyclic parathyroid hormone in women receiving alendronate. N Engl J Med 353:566-75
Iida-Klein, A; Lu, S Shou; Kapadia, R et al. (2005) Short-term continuous infusion of human parathyroid hormone 1-34 fragment is catabolic with decreased trabecular connectivity density accompanied by hypercalcemia in C57BL/J6 mice. J Endocrinol 186:549-57
Kurland, Etah S; Heller, Samantha L; Diamond, Beverly et al. (2004) The importance of bisphosphonate therapy in maintaining bone mass in men after therapy with teriparatide [human parathyroid hormone(1-34)]. Osteoporos Int 15:992-7
Kim, Chi Hyun; Takai, Erica; Zhou, Hua et al. (2003) Trabecular bone response to mechanical and parathyroid hormone stimulation: the role of mechanical microenvironment. J Bone Miner Res 18:2116-25
Rubin, Mishaela R; Bilezikian, John P (2003) New anabolic therapies in osteoporosis. Endocrinol Metab Clin North Am 32:285-307
Zhou, H; Iida-Klein, A; Lu, S S et al. (2003) Anabolic action of parathyroid hormone on cortical and cancellous bone differs between axial and appendicular skeletal sites in mice. Bone 32:513-20
Dempster, David W (2003) The pathophysiology of bone loss. Clin Geriatr Med 19:259-70, v-vi

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