Catalase activity in mouse organs under selenium and/or aluminum ions treatment

Abstract

Abstract. Aim: Antioxidant system in the human body protects cells against reactive oxygen species-induced damage. Catalase is a common enzyme that catalyzes the decomposition of hydrogen peroxide to water and oxygen. It is a very important enzyme in protecting the cell from oxidative damage caused by reactive oxygen species. Metal ions not only cause oxidative stress, but also directly affect the functions of cell enzymes and other important compounds. The aim of this work was to evaluate the effects of selenium and aluminum ions on catalase activity in the liver of laboratory mice and to compare them with previous results of catalase activity in mouse brain under the same conditions. Methods: The experiments were carried out on outbred white laboratory mice using intraperitoneal (IP) injections of Na 2 SeO 3 and/or AlCl 3 solutions. The exposure time was either 24 hours or 14 days. Catalase activity in mouse brain and liver was evaluated on the basis of hydrogen peroxide reaction with ammonium molybdate, which gives a complex that absorbs light of 410 nm wavelength. The concentration of protein in the samples was measured by applying the Warburg-Christian method. The results were expressed as the mean ± SEM. Results: Catalase activity was evaluated in the brain and liver of laboratory mice after single (24 h) or repetitive (14 day-long) injections of SeO 3 2– , Al 3+ , and (SeO 3 2– +Al 3+ ) saline solutions into the abdominal cavity of experimental animals. The results showed that 24 hours after the IP injection of AlCl 3 (0.5 LD 50 ), Na 2 SeO 3 (0.25 LD 50 ), or their mix, catalase activity in mouse brain did not differ between the control and the experimental groups. Meanwhile, 24-hour injections of Al ions significantly reduced catalase activity in mouse liver, while the injections of Se ions increased it. The results showed that the injection of a combination of both metals had no effect on catalase activity in mouse liver cells. In further experiments, we evaluated the effect of SeO 3 2– (0.025 LD 50 ) and/or Al 3+ (0.15 LD 50 ) on catalase activity in mouse organs after 14 days of daily IP injections. In this case, the obtained results showed that Al ions caused a statistically significant increase in catalase activity in the brain and liver of laboratory mice, as compared to the control group, while Se significantly increased catalase activity in mouse liver only. Meanwhile, after 14 days or after 24 hours of exposure, the injections of (SeO 3 2– +Al 3+ ) saline solutions did not affect catalase activity in either of the studied organs. Conclusions: Our study revealed that in the liver, as well as in the brain of the experimental mice, selenium ions could counteract the effect of aluminum ions on the activity of catalase both after 24 hours and after 14 days of intoxication.