Efficacy of zinc treatment against iron-induced toxicity in rat hepatoma cell line H4-II-E-C3.
OBJECTIVE
In this study, we have attempted to explore the possible protection afforded by Zn with regard to its antioxidant potential properties in the iron-induced toxicity.


METHODS
Rat hepatoma cell line H4-II-E-C3 was treated with 150 muM ZnSO4, 200 muM FeSO4 or 150 muM ZnSO4+ 200 muM FeSO4 for 24 h. We studied the effect of metallothionein (MT), glutathione and metal (Fe and Zn) accumulation. We evaluated the levels of both MT-1 and MT-2 mRNAs, activities of antioxidant enzymes, and also determined the distribution of MT and cell death index.


RESULTS
The cotreatment produced highest levels of MT. Fe concentration was significantly lower in the Zn-Fe-treated cells compared with Fe-treated cells. In both Zn treatments, the superoxide dismutase/glutathione peroxidase ratio was similar to control. The cell death index was lower in the Zn-Fe-treated cells compared with Fe-treated cells.


CONCLUSIONS
Zn may act as antioxidant by competitive inhibition of iron uptake by the divalent metal transporter and/or by MT induction.
Formigari
A
A
Department of Biology, University of Padova, Padova, Italy. alessia.formigari@unipd.it
Santon
A
A
Irato
P
P
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D006528:Carcinoma, Hepatocellular / Q000378:metabolism*; D045744:Cell Line, Tumor; D005786:Gene Expression Regulation / Q000187:drug effects; D005978:Glutathione / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D007501:Iron / Q000633:toxicity*; D008668:Metallothionein / Q000378:metabolism; D019216:Metals, Heavy / Q000494:pharmacology; D011485:Protein Binding; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D013482:Superoxide Dismutase / Q000378:metabolism; D015032:Zinc / Q000494:pharmacology*
D000975:Antioxidants; D019216:Metals, Heavy; C491055:Mt2A protein, rat; D012333:RNA, Messenger; D008668:Metallothionein; D007501:Iron; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D005978:Glutathione; D015032:Zinc