Influence of zinc ions on lipid peroxidation in cadmium and nickel treated mice brain and red blood cells

Abstract

Introduction. Heavy metals – cadmium (Cd) and nickel (Ni) are acknowledged as human carcinogens [1, 2]. They can enter into the brain parenchyma and neurons causing neurological alterations in humans and animal models, leading to lower attention, hyper nociception, olfactory dysfunction and memory deficits [3]. Meanwhile, zinc (Zn) may be substituted by toxic metals in some of its important enzymatic and organ functions [4]. However, there is little information about intracellular mechanisms implicated in Zn-dependent protection of an organism against deleterious effects of Cd or Ni. The present study was conducted to evaluate the effects of Cd, Ni and Zn ions on lipid peroxidation in brain and in red blood cells of mice and a possible Zn antioxidant effect against Cd and Ni toxicity. Experiments were done on outbred white laboratory mice using intraperitoneal (i.p.) injections of CdCl2 (14 μmol Cd/kg body weight), NiCl2 (19 μmol Ni/kg body weight) and/or ZnSO4 (24 μmol Zn/kg body weight) solutions. The exposure-time was 14 days. Lipid peroxides were estimated by measuring thiobarbituric-acid-reactive substances and were expressed as malondialdehyde (MDA). Table 1 Experimental groups and the concentrations of used solutions. Group No 14 days of mice brain exposure to i.p. injected salt solutions 1 A single daily injection of CdCl2 (14 μmol Cd/kg body weight) 2 A single daily injection of NiCl2 (19 μmol Ni/kg body weight) 3 A single daily injection of ZnSO4 (24 μmol Zn/kg body weight) 4a) A single daily injection of ZnSO4 and CdCl2 in aforementioned doses 5a) A single daily injection of ZnSO4 and NiCl2 in aforementioned doses a) – For 14 days, mice of 4th and 5th experimental groups were daily pre-treated by i.p. injections of ZnSO4 and after 20 min they received i.p. injections of CdCl2 or NiCl2 solutions, respectively. Mice were tCadmiumed after 24 h following the last CdCl2 or NiCl2 i.p. injections.[...].