Pregnancy can affect bone remodeling through changes in the physical and hormonal environment. Our objective was to understand the bone cell response to physical loading during different stages of pregnancy. Primary bone cells from non-pregnant, 10 days pregnant (10D: corresponding to the second pregnancy trimester) and 18 days pregnant (18D: corresponding to the third pregnancy trimester) ICR mice were obtained. Oscillatory fluid flowinduced shear stress of 1 Pa was applied to bone cells for 1 hour. Real-time RT-PCR was used to determine the changes in mRNA levels of bone resorption-related genes, receptor activator of NF-κB ligand (RANKL) and osteoprotegerin (OPG), and bone formation-related genes, type I collagen (Col I) and osteopontin (OPN). Alkaline phosphatase (ALP) protein activities were also compared. Oscillatory fluid flow did not lead to anabolic response in 10D groups unlike non-pregnant groups displaying no changes in RANKL/OPG mRNA ratio, Col I mRNA level, and OPN mRNA level. 18D groups displayed anabolic responses similar to non-pregnant groups with a significantly greater sensitivity. Our study suggests that bone cells may respond differently to physical loading depending on the different stages of pregnancy. Loading appears to be less effective during the second trimester of pregnancy. Bone cell response to loading is recovered to a much greater extent compared to non-pregnant conditions during the third trimester.
|Number of pages||6|
|Journal||Tissue Engineering and Regenerative Medicine|
|Publication status||Published - 2009 Oct|
All Science Journal Classification (ASJC) codes
- Medicine (miscellaneous)
- Biomedical Engineering