| Co-Investigator(Kenkyū-buntansha) |
MITANI Hideo School of Dentistry, Tohoku University, Professor, 歯学部, 教授 (50014220)
SHIMIZU Yoshinobu School of Dentistry, Tohoku University, Assistant Professor, 歯学部, 助教授 (20005078)
|
|---|
| Research Abstract |
The purpose of this study was to examine the role of various heat shock proteins induced by mechanical stress in periodontium. Periodontal ligament fibroblasts (PDL) and MG-63 osteoblast-like cells were seeded into 6-well culture plates or 6-well flexible silicon plate coated with type I collagen. At the confluent phase, 1,2,4 g/cmィイD12ィエD1 of continuous compressive stress or 1 sec stretching/1 sec relaxation, maximum 15% elongation of cyclic stretching stress was applied for 72 hours. At the end of stimulation period, the cell homogenate was subjected into 10 or 15% SDS polyaclylamide gel electrophoresis and immunoblotted against anti-HSP 27, 47, 60, 70 antibody. Expressions of HSP 47, 60 were stimulated by continuous compressive stress, but HSP 70 production remained almost constant at baseline levels for 72 hours incubation. On the other hand, expression of HSP 47, 60 and 70 were stimulated by cyclic stretching stress after 12 hours of stimulation. PDL which showed low ALPase activity tended to produce HSPs remarkably. In MG-63 cells, cell proliferation was inhibited and the cell death was induced by continuous compressive stress. No apoptotic cells were detected by using TUNEL method. HSP27 production was stimulated with compressive stress after 12 hours of incubation and greater compressive stress tended to induce HSP 27 production in greater mount. HSF-1 production increased with compressive stress for 12 and 24 hours, but the expression of 95 kDa band didn't change markedly. These results indicate HSP may play an important role in the reconstruction process of a periodontium of orthodntically moving tooth, but the pattern of HSP production may be affected by the cell type and the mode of mechanical stress.
|
