Metallothionein synthesis induced by interferon alpha/beta in mice of various zinc status.

Abstract

We studied the ability of interferon alpha/beta (IFN) to induce metallothionein (MT) synthesis in mice. Male mice were injected intraperitoneally with mouse IFN (5 x 10(5) IU/mouse). Plasma Zn levels were reduced at 4 hr after injection, reached a minimum value at 6 hr, and then returned to the control level at 8 hr. Hepatic MT concentrations began to increase at 4 hr and reached maximum values at 6 hr. Induction of MT gene expression and protein synthesis was confirmed by Northern blot analysis and radioimmunoassay, respectively. The induction of MT synthesis in the liver by IFN was dose-dependent. The data suggest that induction of MT-mRNA and the protein in the liver by IFN occurs rapidly but is rather transient. Furthermore, MT synthesis was not induced by IFN in the liver of mice given a Zn-deficient diet, whereas IFN induced increases in the activity of 2',5'-oligoadenylate synthetase in the spleen were unaffected by Zn status. Thus, induction of hepatic MT synthesis by IFN is influenced by Zn status.