The Role of Hormones in the Regulation of Bone Turnover and Eggshell Calcification

The effect of calcium deprivation on the various calcium fluxes was studied in growing rats either sham-operated (SHAM), thyroparathyroidectomized (TPTX), or thyroparathyroidectomized and supplemented with parathyroid hormone (PTH) (TPTX + PTH). In SHAM rats a decrease in the net absorption of calcium (Vna) has no influence on calcemia or on bone formation (Vo+), but leads to an increase in bone resorption (Vo-). In TPTX rats a decrease in Vna induces a decrease in calcemia and in Vo+ but still causes an increase in Vo-. The same is true in TPTX + PTH rats although all the variables measured are increased. In TPTX rats, both without and with PTH, a linear correlation exists between calcemia and Vo+ suggesting that calcemia influences bone formation. Furthermore, it appears that PTH is important in regulating bone turnover, but that the adaptation of Vo- to a change in Vna can occur in the absence or in the presence of a constant amount of this hormone. The mechanism of regulating this adaptation of bone resorption is still unknown.

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The role of the osteocyte in bone turnover

Bone ◽

10.1016/j.bone.2008.07.258 ◽

2008 ◽

Vol 43 ◽

pp. S22

Author(s):

Brendon Noble

Keyword(s):

Bone Turnover

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Serumβ-Catenin Levels Associated with the Ratio of RANKL/OPG in Patients with Postmenopausal Osteoporosis

International Journal of Endocrinology ◽

10.1155/2013/534352 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7 ◽

Cited By ~ 5

Author(s):

Xiao-Juan Xu ◽

Lin Shen ◽

Yan-Ping Yang ◽

Rui Zhu ◽

Bo Shuai ◽

...

Keyword(s):

Bone Turnover ◽

Postmenopausal Women ◽

Postmenopausal Osteoporosis ◽

Bone Turnover Markers ◽

Enzyme Linked Immunosorbent Assay ◽

Functional Communication ◽

Mineral Density ◽

Wnt Pathways ◽

Turnover Markers

Objective. To demonstrate the role of Wnt/β-catenin canonical pathway in postmenopausal osteoporosis by evaluating serumβ-catenin levels in patients with postmenopausal osteoporosis and analyzing their possible relationship with serum OPG, RANKL, the ratio of RANKL/OPG, sclerostin, and bone turnover markers.Methods. 480 patients with postmenopausal osteoporosis and 170 healthy postmenopausal women were enrolled in the study. Serumβ-catenin, OPG, RANKL, and sclerostin levels were measured by enzyme-linked immunosorbent assay. Bone status was assessed by measuring bone mineral density and bone turnover markers. Estradiol levels were also detected.Results. Serumβ-catenin levels were lower in postmenopausal osteoporotic women compared to nonosteoporotic postmenopausal women (26.26±14.81versus39.33±5.47 pg/mL,P<0.001). Serumβ-catenin was positively correlated with osteoprotegerin (r=0.232,P<0.001) and negatively correlated with the ratio of RANKL/OPG, body mass index, and sclerostin (r=-0.128,P=0.005;r=-0.117,P=0.010;r=-0.400,P<0.001, resp.) in patients with postmenopausal osteoporosis.Conclusion. The results indicate that lower serumβ-catenin and concomitantly higher ratio of RANKL/OPG may be involved in the pathogenesis of postmenopausal osteoporosis. Functional communication between RANKL/RANK/OPG system and Wnt pathways plays an important role in postmenopausal osteoporosis.

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The complex role of bone turnover biomarkers in cardiovascular diseases

European Journal of Heart Failure ◽

10.1093/eurjhf/hft047 ◽

2013 ◽

Vol 15 (6) ◽

pp. 709-710

Author(s):

Juan A. Vílchez ◽

Diana Hernández-Romero ◽

Francisco Marín

Keyword(s):

Cardiovascular Diseases ◽

Bone Turnover ◽

Bone Turnover Biomarkers

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A Dual Role of Upper Zone of Growth Plate and Cartilage Matrix–Associated Protein in Human and Mouse Osteoarthritic Cartilage: Inhibition of Aggrecanases and Promotion of Bone Turnover

Arthritis & Rheumatology ◽

10.1002/art.40042 ◽

2017 ◽

Vol 69 (6) ◽

pp. 1233-1245 ◽

Cited By ~ 14

Author(s):

Michael Stock ◽

Stefanie Menges ◽

Nicole Eitzinger ◽

Maria Geßlein ◽

Renate Botschner ◽

...

Keyword(s):

Bone Turnover ◽

Growth Plate ◽

Dual Role ◽

Cartilage Matrix ◽

Osteoarthritic Cartilage ◽

Human And Mouse ◽

And Cartilage

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The role of B cells in bone turnover in rheumatoid arthritis

International Journal of Clinical Rheumatology ◽

10.2217/ijr.12.5 ◽

2012 ◽

Vol 7 (2) ◽

pp. 167-177

Author(s):

Mohsen H Elshahaly ◽

Gillian Wheater ◽

Stephen P Tuck ◽

Harish K Datta ◽

Jacob M van Laar

Keyword(s):

Rheumatoid Arthritis ◽

B Cells ◽

Bone Turnover

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Role of oestrogen in the regulation of bone turnover at the menarche

Journal of Endocrinology ◽

10.1677/joe.1.06059 ◽

2005 ◽

Vol 185 (2) ◽

pp. 223-234 ◽

Cited By ~ 87

Author(s):

Richard Eastell

Keyword(s):

Bone Turnover ◽

Cancellous Bone ◽

Bone Remodelling ◽

High Rate ◽

Mineral Density ◽

Early Puberty ◽

Increased Risk ◽

Periosteal Apposition ◽

Turnover Markers

The rise in oestrogen levels at menarche in girls is associated with a large reduction in bone turnover markers. This reduction reflects the closure of the epiphyseal growth plates, the reduction in periosteal apposition and endosteal resorption within cortical bone, and in bone remodelling within cortical and cancellous bone. Oestrogen promotes these changes, in part, by promoting apoptosis of chondrocytes in the growth plate and osteoclasts within cortical and cancellous bone. The period of early puberty is associated with an increased risk of fracture, particularly of the distal forearm, and this may be related to the high rate of bone turnover. A late menarche is a consistent risk factor for fracture and low bone mineral density in the postmenopausal period; models that might explain this association are considered.

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