17beta-estradiol combined with testosterone promotes chicken osteoblast proliferation and differentiation by accelerating the cell cycle and inhibiting apoptosis in vitro.
Medullary bone is a unique tissue in the long bones cavities of lay hens, and plays an important role as a calcium reservoir for egg-shell formation. Medullary bone formation requires the synergistic action of estrogen and androgen on osteoblasts during the early stage of sexual maturity. The objective of the current study was to investigate the effects of 17beta-estradiol, testosterone, and the combination on the proliferation, alkaline phosphatase (ALP) activity, apoptosis, the cell cycle of chicken osteoblasts in vitro. The proliferation of osteoblasts was examined with the MTT assay. Apoptosis and the cell cycle were assessed with flow cytometry. Either 17beta-estradiol (200 pg ml(-1)) or testosterone (100 pg ml(-1)) or the combination (100 pg ml(-1) each) significantly enhanced osteoblast proliferation and ALP activity, accelerated the osteoblast cell cycle, and stimulated osteoblast DNA synthesis in a period of 24 h. 17beta-estradiol, used alone or with testosterone, inhibited chicken osteoblast apoptosis; However, testosterone alone induced cell apoptosis. In conclusion, 17beta-estradiol combined with testosterone promoted osteoblast proliferation and ALP activity, accelerated the osteoblast cell cycle, inhibited osteoblast apoptosis.
Chen
Xiuxia
X
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China.
Deng
Yifeng
Y
Zhou
Zhenlei
Z
Tao
Qingshu
Q
Zhu
Jie
J
Li
Xiaolan
X
Chen
Jinli
J
Hou
Jiafa
J
D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D001842:Bone and Bones / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D002453:Cell Cycle / Q000187:drug effects*; D048708:Cell Growth Processes / Q000187:drug effects; D002478:Cells, Cultured; D002645:Chickens / Q000502:physiology*; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D005434:Flow Cytometry; D005562:Formazans / Q000737:chemistry; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D013739:Testosterone / Q000494:pharmacology*; D013778:Tetrazolium Salts / Q000737:chemistry
D005562:Formazans; D013778:Tetrazolium Salts; C079782:MTT formazan; D013739:Testosterone; D004958:Estradiol; D000469:Alkaline Phosphatase