Chromium (VI) can activate and impair antioxidant defense system.
The changes in glutathione-dependent cycle enzymes and catalase activities under Cr(VI)-induced oxidative stress were investigated in two distinct cell lines: L-41-human epithelial-like cells and HLF-fetal human diploid lung fibroblasts, which differ in tissue origin, proliferation, and antioxidant enzymes activities. The chromium concentrations from 1 to 5 μM cause nontoxic effects and activate antioxidant enzymes to overcome oxidative stress. In spite of some differences in the endogenous antioxidant activities, both cell lines reveal the same range of toxic concentrations (20-30 μM). The irreversible inhibition of glutathione-dependent antioxidant enzymes develops under toxic concentrations and serves as a marker of toxicity. The endogenous antioxidant activity influences time-dependent expression of Cr(VI) toxicity and the dynamics of antioxidant enzymes activity under nontoxic conditions. The cell antioxidant defense system is an important marker of the cell adaptive capacity under nontoxic and toxic conditions.
Asatiani
Nino
N
Department of Physics of Biological Systems, Andronikashvili Institute of Physics, 6, Tamarashvili St, 0177 Tbilisi, Georgia.
Kartvelishvili
Tamar
T
Abuladze
Marina
M
Asanishvili
Lali
L
Sapojnikova
Nelly
N
D000975:Antioxidants / Q000378:metabolism*; D002374:Catalase / Q000378:metabolism; D002460:Cell Line; D002857:Chromium / Q000633:toxicity*; D004789:Enzyme Activation / Q000187:drug effects; D005979:Glutathione Peroxidase / Q000378:metabolism; D005980:Glutathione Reductase / Q000378:metabolism; D006801:Humans; D018384:Oxidative Stress / Q000187:drug effects
D000975:Antioxidants; D002857:Chromium; D002374:Catalase; D005979:Glutathione Peroxidase; D005980:Glutathione Reductase