Effect of cobalt and chromium ions on human MG-63 osteoblasts in vitro: morphology, cytotoxicity, and oxidative stress.
Recent studies demonstrated that Co(2+) and Cr(3+) ions induced cell mortality, TNF-alpha secretion, and oxidation of proteins in macrophages. However, little is known about the effects of corrosion products on the osteogenic cells, which have a crucial role in controlling bone remodeling. The aim of the present study was to investigate the effect of Co(2+) (0-10 ppm) and Cr(3+) (0-150 ppm) on human MG-63 osteoblast-like cells in term of cytotoxicity and oxidative stress. Microscopic analysis demonstrated changes in shape, size, and number of cells. Co(2+) had a greater effect on these parameters than Cr(3+). Cell counting showed a significant decrease in the number of MG-63 osteoblasts in a time- and dose-dependent manner, with Co(2+) more toxic than Cr(3+). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) analysis also showed a decreased cellular activity in presence of Co(2+) and Cr(3+) ions. Oxidized and nitrated proteins, two markers of oxidative stress, were detected as single bands and revealed time- and dose-dependent protein modifications. We also studied the expression of three antioxidant enzymes. The expression of heme oxygenase-1 was increased by both ions after 24h, before decreasing gradually thereafter. Glutathione peroxidase expression was also increased in a concentration- and time-dependent manner by both Co(2+) and Cr(3+) ions. Co(2+) decreased catalase expression while Cr(3+) increased it in a dose- and time-dependent manner. In conclusion, this study demonstrated that Cr(3+) and Co(2+) have a cytotoxic effect on MG-63 osteoblasts and have the potential to modify their redox state.
Fleury
Cyrille
C
Division of Orthopaedic Surgery, McGill University, Lady Davis Institute for Medical Research, The Sir Mortimer B. Davis-Jewish General Hospital, 3775 Chemin de la Côte Sainte Catherine, Montreal, Que., Canada H3 T 1E2.
Petit
Alain
A
Mwale
Fackson
F
Antoniou
John
J
Zukor
David J
DJ
Tabrizian
Maryam
M
Huk
Olga L
OL
D002374:Catalase / Q000032:analysis / Q000378:metabolism; D002478:Cells, Cultured; D002857:Chromium / Q000633:toxicity*; D003035:Cobalt / Q000633:toxicity*; D005979:Glutathione Peroxidase / Q000032:analysis / Q000378:metabolism; D051547:Heme Oxygenase-1 / Q000032:analysis / Q000378:metabolism; D006801:Humans; D007477:Ions / Q000633:toxicity; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D013778:Tetrazolium Salts / Q000494:pharmacology; D013844:Thiazoles / Q000494:pharmacology
D007477:Ions; D013778:Tetrazolium Salts; D013844:Thiazoles; D002857:Chromium; D003035:Cobalt; D002374:Catalase; D005979:Glutathione Peroxidase; D051547:Heme Oxygenase-1; C022616:thiazolyl blue