Cadmium chloride-induced oxidative stress in skeletal muscle cells in vitro.
The effects of cadmium chloride (CdCl(2)) on oxidative stress in the skeletal muscle cell line C(2)C(12) were investigated. Myoblast cells that differentiated into myotubes were treated with CdCl(2) (1, 3, 5, 7.5, 10, and 12.5 microM) for 24, 48, and 72 h. Subsequent assay of cell homogenates for MTT (3-(4,5-dimethylthiozol-2-yl)-2,5-diphenyltetrazolium bromide) reduction, neutral red uptake and nucleic acid content showed that cadmium was toxic to C(2)C(12) cells in a concentration-dependent manner. Glutathione-S-transferase activity (nmol microg of protein(-1) min(-1)) was increased with 1 and 3 microM CdCl(2) (36.9 +/- 5.6 and 32.1 +/- 6.0, respectively) compared to control cells (21.8 +/- 1.5), but decreased at higher concentrations (7.5 microM = 15.9 +/- 3.3, 10 microM = 15.9 +/- 4.6, and 12.5 microM = 10.5 +/- 2.8). An increase in malondialdehyde content (nmol microg of protein(-1)), especially at high CdCl(2) concentrations (control = 7.3 +/- 0.5; CdCl(2): 7.5 microM = 11.2 +/- 3.1, 10 microM = 14.6 +/- 3.8, and 12.5 microM = 20.5 +/- 6.5) indicated that there was enhanced lipid peroxidation. Light and scanning electron microscopy showed that there was a concentration-dependent loss of adherent cells and the formation of vesicles indicative of cell death. These results indicated that CdCl(2) increased oxidative stress in C(2)C(12) cells, and this stress probably compromised cell adhesion and the cellular antioxidant defense mechanisms.
Yano
Claudia Lumy
CL
Departamento de Fisiologia e Biofísica e Departamento de Biologia Celular, Instituto de Biologia, Universidade Estadual de Campinas UNICAMP, CP 6109, 13083-970, Campinas, São Paulo, SP, Brazil.
Marcondes
Maria Cristina Cintra Gomes
MC
D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D019256:Cadmium Chloride / Q000494:pharmacology*; D002448:Cell Adhesion; D016923:Cell Death; D002454:Cell Differentiation; D002460:Cell Line; D002470:Cell Survival; D004305:Dose-Response Relationship, Drug; D005982:Glutathione Transferase / Q000378:metabolism; D066298:In Vitro Techniques; D015227:Lipid Peroxidation; D051379:Mice; D008855:Microscopy, Electron, Scanning; D018482:Muscle, Skeletal / Q000166:cytology* / Q000648:ultrastructure; D018384:Oxidative Stress; D015398:Signal Transduction; D013778:Tetrazolium Salts / Q000494:pharmacology; D013844:Thiazoles / Q000494:pharmacology; D013997:Time Factors
D000975:Antioxidants; D013778:Tetrazolium Salts; D013844:Thiazoles; D005982:Glutathione Transferase; C022616:thiazolyl blue; D019256:Cadmium Chloride