TY - JOUR
T1 - Mechanical loading induced osteocyte apoptosis and connexin 43 expression in three-dimensional cell culture and dental implant model
AU - Takemura, Yoko
AU - Moriyama, Yasuko
AU - Ayukawa, Yasunori
AU - Kurata, Kosaku
AU - Rakhmatia, Yunia D.
AU - Koyano, Kiyoshi
N1 - Funding Information:
Correspondence to: Yasuko Moriyama; e-mail: kabay@dent.kyushu-u.ac.jp Contract grant sponsor: JSPS KAKENHI; contract grant number: Grant Number 26462925 Contract grant sponsor: Japan Society for the Promotion of Science; contract grant number: 26462925
Funding Information:
This study was supported in part by JSPS KAKENHI Grant Number JP26462925 from the Japan Society for the Promotion of Science.
Publisher Copyright:
© 2018 Wiley Periodicals, Inc.
PY - 2019/4
Y1 - 2019/4
N2 - Osteocytes are thought to act as stress sensors, and are known to display a gap junction-mediated stress-transfer mechanism. To demonstrate the stress-related function of osteocytes, cells of an osteocyte-like cell line derived from murine long bone osteocyte Y4 (MLO-Y4) were cultivated in a three-dimensional culture and subjected to cyclic loading from a titanium plate. This application of physiological loading using a titanium plate significantly increased connexin 43 (Cx43) expression, the number of dead and apoptotic cells, and receptor activator of nuclear factor κB ligand expression. Furthermore, the conditioned medium from the loaded osteocytes induced alkaline phosphatase activity in bone marrow cell culture. In addition, we immunohistologically determined whether bone metabolism increased as a result of the occlusal force in the bone surrounding the titanium implants in a rat model. Increased Cx43 expression and apoptotic osteocytes were observed in the loading group as well as a significantly increased number of tartrate-resistant acid phosphatase-positive cells. These findings indicate that stress from the implant adversely affected the osteocytes, which may promote osteoclastic and osteoblastic cell formation around the implants.
AB - Osteocytes are thought to act as stress sensors, and are known to display a gap junction-mediated stress-transfer mechanism. To demonstrate the stress-related function of osteocytes, cells of an osteocyte-like cell line derived from murine long bone osteocyte Y4 (MLO-Y4) were cultivated in a three-dimensional culture and subjected to cyclic loading from a titanium plate. This application of physiological loading using a titanium plate significantly increased connexin 43 (Cx43) expression, the number of dead and apoptotic cells, and receptor activator of nuclear factor κB ligand expression. Furthermore, the conditioned medium from the loaded osteocytes induced alkaline phosphatase activity in bone marrow cell culture. In addition, we immunohistologically determined whether bone metabolism increased as a result of the occlusal force in the bone surrounding the titanium implants in a rat model. Increased Cx43 expression and apoptotic osteocytes were observed in the loading group as well as a significantly increased number of tartrate-resistant acid phosphatase-positive cells. These findings indicate that stress from the implant adversely affected the osteocytes, which may promote osteoclastic and osteoblastic cell formation around the implants.
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U2 - 10.1002/jbm.a.36597
DO - 10.1002/jbm.a.36597
M3 - Article
C2 - 30578719
AN - SCOPUS:85059587544
VL - 107
SP - 815
EP - 827
JO - Journal of Biomedical Materials Research - Part A
JF - Journal of Biomedical Materials Research - Part A
SN - 1549-3296
IS - 4
ER -