Influence of long-term cadmium ions exposure on mitotic and apoptotic activities and protein synthesis in mouse liver

Abstract

The aim of this study was to evaluate in vivo the effects of long-term exposure to cadmium ions (Cd2+) on cell death, mitotic activity and translational machinery of mouse liver cells. It was determined that after intraperitoneal injections of cadmium chloride solution (0.16 mg Cd2+ per 1 kg of body mass) for six weeks, three times per week, the number of TUNEL positive cells containing fragmented nuclei was significantly higher than in control (p < 0.0001); the median score was 1. Cadmium-induced cell death was accompanied by activation of mitosis. These data indicate an activation of liver regeneration during sub-chronic exposure to Cd2+. Examination of liver translation showed that Cd2+ reduced both the incorporation of [14C]-labeled leucine into newly synthesized peptides and proteins and the acceptor activity of tRNALeu. In comparison with the control, liver exposure to Cd2+ caused activation of leucyl-tRNA synthetase. Keywords: cadmium, mitotic index, protein synthesis, tRNA, leucyl-tRNA synthetase, apoptosis