Cytotoxic and Oxidative Stress Caused by Cadmium and Lead on Human Skin Fibroblast Cells

Introduction: Heavy metals are important occupational andenvironmental pollutants that cause damage to various organs.Although there is no effective therapy for such a poisoning,metallothionein has been shown to play a key role in thedetoxification of cadmium (Cd). Evidence in the literature suggeststhat superoxide dismutase, glutathione peroxidase, and catalaseconstitute important defense mechanisms against oxygen toxicity inthe cells. The aim of this study was to investigate the effect ofcadmium chloride and Pb-acetate on antioxidant enzymes in thehuman skin fibroblast cells (HF2FF).Material and Methods: The human skin fibroblast (HF2FF) cellswere incubated in serum-free medium containing 20 μM CdCl2 for18 hr three times a week. The same exposure to an equimolar doseof Pb-acetate was performed. After each exposure and after threetimes exposure the cells were collected and cell viability, thecontents of superoxide dismutase (SOD), catalase, glutathioneperoxidase (GSH-Px), GSH and malondialdehyde (MDA) weremeasured.Results: Cd caused cytotoxicity and inhibition of glutathioneperoxidase (GSH-Px) and SOD activity, as well as depletion of thereduced form of glutathione (GSH) in the cell. The level of lipidperoxidation (LP) was increased, but catalase activity was notsignificantly altered. These defects were increased with repeatedexposures. The same exposure to an equimolar dose of Pb-acetateevoked only inhibition of GSH-Px and SOD. The values of GSH,catalase and LP activity remained unchanged.Conclusion: The inhibition of GSH-Px and SOD may be consideredas an important biomarker of the toxic effect of metals