[Parathyroid hormone inhibits the apoptosis of osteoblast MC-3T3E1 cells through a non-PLC-dependent protein kinase C pathway].
OBJECTIVE
To investigate the effect of the non-PLC-dependent protein kinase C (PKC) pathway of parathyroid hormone (PTH) on the apoptosis and proliferation of osteoblast MC-3T3E1 cells.


METHODS
MC-3T3E1 cells were seeded in 96-well plates at the density of 1.5×10(4) cells/mL and incubated for 3 day. The cells were then exposed to 100 nmol/L of [Gly(1), Arg(19)]hPTH(1-28), 100 nmol/L of [Gly(1), Arg(19)]hPTH(1-34), 100 nmol/L of [Gly(1), Arg(19)]hPTH(1-34)+1 µmol/L Go6983, 1 µmol/L Go6983, or deionized water (control) for 1, 24 or 48 h. After the treatments, cell counting kit-8 (CCK-8) and Caspase-Glo® 3/7 Assay (Caspase-3) were used to examine the proliferation and apoptosis of MC3T3-E1 cells.


RESULTS
CCK-8 results showed that hPTH(1-34) increased the number of MC3T3-E1 cells compared with hPTH(1-34)+Go6983 at 1 h and 24 h, but this difference was not statistically different. At 48 h, treatment with hPTH(1-34), as compared with hPTH(1-28), significantly increased the number of MC3T3-E1 cells (P<0.05), and this effect was blocked by the PKC inhibitor Go6983 (P<0.05). hPTH(1-34) did not result in significant inhibition of MC3T3-E1 cell apoptosis at 1 h and 24 h as compared with hPTH(1-34)+Go6983, but significantly inhibited the cell apoptosis as compared with hPTH(1-28) (P<0.05); this inhibitory effect was blocked by Go6983 (P<0.05).


CONCLUSIONS
s A relatively long time (for 48 h) of exposure to PTH can inhibit apoptosis and promote the proliferation of MC3T3-E1cells through a non-PLC-dependent PKC pathway.
Department of Spinal Surgery, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China. E-mail: hsywst@163.com.
Shao-Yu
SY
Hu
Guo-Jun
GJ
Tong
Yue
Y
Meng
Song
S
Hao
Wei
W
Li
Fu-Long
FL
Xu
You-Hua
YH
He
Jian-Ting
JT
Chen
De-Hong
DH
Yang
D016475:3T3 Cells; D000818:Animals; D017209:Apoptosis; D049109:Cell Proliferation; D007211:Indoles / Q000494:pharmacology; D008301:Maleimides / Q000494:pharmacology; D051379:Mice; D010006:Osteoblasts; D010281:Parathyroid Hormone / Q000494:pharmacology*; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism*; D015398:Signal Transduction
C465664:2-(1-(3-dimethylaminopropyl)-5-methoxyindol-3-yl)-3-(1H-indol-3-yl)maleimide; D007211:Indoles; D008301:Maleimides; D010281:Parathyroid Hormone; D011493:Protein Kinase C