Integrity of the osteocyte bone cell network in osteoporotic fracture: implications for mechanical load adaptation
Date
2010
Authors
Kuliwaba, V.
Truong, L.
Codrington, J.
Fazzalari, N.
Editors
Khalili, N.
Valliappan, S.
Li, Q.
Russell, A.
Valliappan, S.
Li, Q.
Russell, A.
Advisors
Journal Title
Journal ISSN
Volume Title
Type:
Conference paper
Citation
Proceedings of the 6th Australasian Congress on Applied Mechanics, 2010: pp.1-7
Statement of Responsibility
Conference Name
Australasian Congress on Applied Mechanics (6th : 2010 : Perth, Western Australia)
Abstract
The human skeleton has the ability to modify its material composition and structure to accommodate loads through adaptive modelling and remodelling. The osteocyte cell network is now considered to be central to the regulation of skeletal homeostasis; however, very little is known of the integrity of the osteocyte cell network in osteoporotic fragility fracture. This study was designed to characterise osteocyte morphology, the extent of osteocyte cell apoptosis and expression of sclerostin protein (a negative regulator of bone formation) in trabecular bone from the intertrochanteric region of the proximal femur, for postmenopausal women with fragility hip fracture compared to age-matched women who had not sustained fragility fracture. Osteocyte morphology (osteocyte, empty lacunar, and total lacunar densities) and the degree of osteocyte apoptosis (percent caspase-3 positive osteocyte lacunae) were similar between the fracture patients and non-fracture women. The fragility hip fracture patients had a lower proportion of sclerostin-positive osteocyte lacunae in comparison to sclerostin-negative osteocyte lacunae, in contrast to similar percent sclerostin-positive/sclerostin-negative lacunae for non-fracture women. The unexpected finding of decreased sclerostin expression in trabecular bone osteocytes from fracture cases may be indicative of elevated bone turnover and under-mineralisation, characteristic of postmenopausal osteoporosis. Further, altered osteocytic expression of sclerostin may be involved in the mechano-responsiveness of bone. Optimal function of the osteocyte cell network is likely to be a critical determinant of bone strength, acting via mechanical load adaptation, and thus contributing to osteoporotic fracture risk.
School/Discipline
Dissertation Note
Provenance
Description
Access Status
Rights
Copyright status unknown