| Autor: |
Nichols RA Jr; 1 US Army Periodontic Residency Program, Dental Activity, Fort Gordon, Ga., Niagro FD; 2 Clinical Investigation Division, Dwight D. Eisenhower Army Medical Center, Fort Gordon, Ga., Borke JL; 3 Western University of Health Sciences, College of Dental Medicine, Pomona, Calif., Cuenin MF; 4 Carolina Center for Restorative Dentistry, Mount Pleasant, SC. |
| Jazyk: |
angličtina |
| Zdroj: |
The Journal of oral implantology [J Oral Implantol] 2016 Apr; Vol. 42 (2), pp. 138-44. Date of Electronic Publication: 2015 May 11. |
| DOI: |
10.1563/aaid-joi-D-14-00199 |
| Abstrakt: |
Bone to mechanical loading elicits a biological response that has clinical significance for several areas in dental medicine, including orthodontic tooth movement, tempromandibular joint disease, and endosseous dental implant osseointegration. Human orthopedic studies of failed hip implant sites have identified increased mRNA expression of several collagen-degrading matrix metalloproteinases (MMPs), while in vitro experiments have shown increases in MMP secretion after exposure to inflammatory mediators. This investigation evaluates the effects of mechanical deformation on in vitro osteoblasts by assessing changes in MMP gene expression and enzyme activity. We seeded mouse neonatal calvarial osteoblasts onto flexible 6-well plates and subjected to continuous cyclic mechanical stretching. The expression and activity of mRNA for several MMPs (2, 3, 9, and 10) was assessed. When subjected to mechanical stress in culture, only mRNA specific for MMP-9 was significantly increased compared to nonstretched controls (P < .005). Measurement of MMP activity by gelatin zymography demonstrated that none of the MMPs showed increased activity with stretching; however, MMP-2 activity decreased. Our results suggest that in response to stretch, MMP-2 responds rapidly by inhibiting conversion of a MMP-2 to the active form, while a slower up-regulation of MMP-9 may play a role in the long-term remodeling of extracellular matrix in response to continuous mechanical loading. This study suggests that the regulation of metalloproteinases at both the mRNA and protein level are important in the response of bone to mechanical stress. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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