Combined effects of γ-irradiation and cadmium exposures on osteoblasts in vitro.
The combined effects of γ-irradiation and cadmium (Cd) exposures on osteoblasts were observed in the present study. Osteoblasts were exposed to γ-irradiation (0.5 Gy) and Cd (0-0.5 μmol/L). Cell viability, alkaline phosphatase (ALP) activity, mineralization ability, cell apoptosis and genes expression of ALP, osteocalcin (OC) and caspase 3 were observed. Low concentrations of Cd exposure had no obvious influence on cell viability, ALP activity and apoptosis. However, low levels of Cd exposure combined with γ-irradiation induced more toxic effects on osteoblasts than those treated with Cd or irradiation alone. High concentrations of Cd combined with irradiation exposure induced more significant inhibition in cell viability, ALP activity and mineralization ability than those exposed to Cd or irradiation alone. Meanwhile, OC and ALP mRNA expression of cells treated with Cd combined with irradiation were down-regulated more significantly than those treated with Cd or irradiation alone. Cd combined with γ-irradiation could obviously enhance osteoblast apoptosis and up-regulated caspase 3 mRNA expression compared with those treated with Cd or irradiation alone. This study indicated that ionizing irradiation can enhance Cd toxic effects on osteoblast viability and differentiation and apoptosis may play an important role in this progress.
Department of Environmental Epidemiology and Bone Toxicology, Institute of Radiation Medicine, Fudan University, China.
Jing
J
Qiu
Guoying
G
Zhu
Xiao
X
Chen
Chunlin
C
Shao
Shuzhu
S
Gu
D000469:Alkaline Phosphatase / Q000235:genetics / Q000378:metabolism; D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000528:radiation effects; D019256:Cadmium Chloride / Q000633:toxicity*; D002113:Calcification, Physiologic / Q000187:drug effects / Q000528:radiation effects; D053148:Caspase 3 / Q000235:genetics; D002454:Cell Differentiation / Q000187:drug effects / Q000528:radiation effects; D049109:Cell Proliferation / Q000187:drug effects / Q000528:radiation effects; D048430:Cell Shape / Q000187:drug effects / Q000528:radiation effects; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004785:Environmental Pollutants / Q000633:toxicity*; D005720:Gamma Rays; D005786:Gene Expression Regulation / Q000187:drug effects / Q000528:radiation effects; D010006:Osteoblasts / Q000187:drug effects* / Q000378:metabolism / Q000528:radiation effects*; D015675:Osteocalcin / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats
D004785:Environmental Pollutants; D012333:RNA, Messenger; D015675:Osteocalcin; D000469:Alkaline Phosphatase; C505410:Casp3 protein, rat; D053148:Caspase 3; D019256:Cadmium Chloride