ACTIVITY OF GLUTATHIONE PEROXIDASE IN LOACH EMBRYOS UNDER THE INFLUENCE OF FLUOROQUINOLON ANTIBIOTICS

Abstract

Background. In modern biology, a search test system that would allow adequate assessment of the effect of pharmacological agents on the human and animal body remains relevant. The use of embryonic objects is promising in the study of the toxicity of low-level substances, in particular, antibiotics of the fluoroquinolone class, borocin and flumiquil. They have a wide range of action and are used to treat diseases of the central nervous system, inflammatory processes, diseases of the endocrine system. Additionally, these antibiotics can serve as anticancer and antiviral drugs. However, the degree of toxicity and the mechanism of their effect on the cell have not been fully studied. Glutathione chain enzymes, particularly glutathione peroxidase activity, can serve as a sensitive indicator for assessing the body’s response to external influences.
This study aimed at exploring the possibilities of using embryonic objects as a test system for testing the effects of harmful substances. In particular, we investigated the activity of glutathione peroxidase in loach embryos under the influence of flumiquil and borocin in concentrations of 2.5; 1.5 and 0.25 μg/mL during early embryogenesis (after 1, 3, and 5 hours of development).
Materials and Methods. The research was carried out on embryos of the loach Missgurnus fossilis L., eggs were obtained and fertilized according to A. A. Neifakh. Ovulation was stimulated by intraperitoneal injection of the human placental hormone – chorionic gonadotropin in loach females acclimatized at 18 °C. Within a period of 36–48 hours following the injection of gonadotropin, caviar was obtained and fertilized in Petri dishes with a suspension of sperm in settled tap water obtained “ex tempore” from the testes of males (caviar retains the ability to be fertilized for 5 minutes). After 1 min, the zygotes were finally washed from the excess sperm, the caviar attached to the bottom of the cup was rinsed, and in the control series they were incubated in Holtfreter’s solution at a temperature of 20–22 °C. The concentration of reduced glutathione before and after the incubation was determined colorimetrically. The basis of the development of the color reaction is the interaction of the SH-group with 5,5′ dithio-bis (2-nitrobenzoic) acid (DTNBA) with the formation of a colored product – thionitrophenyl anion (TNPA). The amount of the latter is directly proportional to the number of SH-groups that reacted with DTNBA. To find out the effect of the studied fluoroquinolones on the change in the acti­vity of the enzymes of the antioxidant system, borocin and flumiquil at concentrations of 2.5 μg/mL, 1.5 μg/mL and 0.25 μg/mL were added to the medium in which loach embryo cells were cultivated.
Results. We investigated the influence of borocin and flumiquil at concentrations of 0.25, 1.5, and 2.5 μg/mL on the development of the embryos of Misgurnus fossilis L. after 1, 3, and 5 hours of exposure. It was found that borocin and flumiquil exert an active effect on the dynamic activity of glutathione peroxidase. The overall activity dynamics under the action of borocin and flumiquil in all three cases was very similar. After 1, 3, and 5 hours of development under the action of borocin, an increase in the activity of the enzyme under study was observed. The highest activating effect was manifested at a concentration of 0.25 μg/mL.
Conclusions. It was found that borocin and flumiquil have an activating effect on the dynamics of glutathione peroxidase activity. The study of enzymes of the glutathione system showed that the GPO activity of loach embryos incubated in the studied media increased the most after 3 hours of development.