Evaluation of the protective effect of two weeks administration of zinc on protein synthesis in the liver of cadmium-treated mice

Objective: The present study was conducted to evaluate the protective effects of zinc (Zn) ions on the rate of protein synthesis and on the activities of key components of protein synthesis machinery – transfer ribonucleic acids (tRNA) and aminoacyl-tRNA synthetases (ARS) in the liver of cadmium (Cd)-treated mice. Methods: Experiments were performed with white outbred laboratory mice using intraperitoneal (i.p.) injections of CdCl2 and/or ZnSO4 solutions. The exposure-time was 14 days. The rate of protein synthesis was evaluated by incorporation of [14C]-labeled leucine into newly synthesized peptides and proteins. Activities of tRNALeu and leucyltRNA synthetase (LRS) were assessed in mice liver by aminoacylation reaction using [14C]-labeled leucine. Results: Our results showed that after 14 days of injections, the rate of protein synthesis and the activity of LRS in Zn and Zn+Cd groups were at the control level. Meanwhile, in Cd-treated group the rate of protein synthesis and the activity of LRS were increased by 27% and 25%, respectively. The acceptor activity of tRNALeu was considerably lower in all experimental groups by 49-76%. Conclusions: After 14 injections, Zn ions partly prevented the activities of tRNALeu and LRS from Cd-induced changes.