Evaluation of the state of glutathione antiperoxidant system of oral fluid in adolescent smoking girls

The powerful glutathione antiperoxidant system, which is involved in three of the four lines of defence, plays a leading role in providing antioxidant protection in the human body. It is represented by reduced glutathione and enzymes of its metabolism: glutathione peroxidase, glutathione transferase and glutathione reductase. Aim - to study the state of the glutathione antiperoxidant system of the oral fluid in adolescent smoking girls. Materials and methods. The study of indicators of the glutathione antiperoxidant system of oral fluid in 137 adolescent girls aged 18 to 24 years was conducted. The level of reduced glutathione was determined by the method of Travina O.V. (1955). The state of the system of glutathione-dependent enzymes was assessed by the activity of glutathione peroxidase - by the method of Vlasova SN et al. (1990); glutathione transferase activity - by the method of Vlasova SN et al. (1990); glutathione reductase activity - by the methods of biochemical studies edited by M.I. Prokhorova (1982). Results. In adolescent girls who smoke traditional cigarettes, the most pronounced decrease in reduced glutathione activity was observed, which was 2.1 times less than in non-smokers. In participants who regularly smoked electronic cigarettes (vapes), the average activity of reduced glutathione in oral fluid was 3.75±0.02 mlmol/l, and in people who regularly smoked tobacco heating devices (IQOS) - 3.67±0.02 mlmol/l, which was 1.5 times less compared to non-smokers. Changes in the functioning of glutathione-dependent enzymes in the oral fluid of the study participants were also found depending on the presence of a bad habit and type of smoking. The glutathione-dependent enzymes of the oral fluid were characterised by activation of glutathione peroxidase and significant deficiency of glutathione transferase and glutathione reductase. Conclusions. Thus, the changes in reduced glutathione and the system of glutathione-dependent enzymes of oral fluid in adolescent girls, which occur under the influence of smoking, depend on the type of smoking and are characterised by a decrease in the activity of reduced glutathione, glutathione transferase and glutathione reductase enzymes, as well as activation of the glutathione peroxidase enzyme. The study was conducted in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the local ethics committee of the participating institution. Informed consent was obtained from all patients. No conflict of interests was declared by the authors.