Catalytic properties of glutathione peroxidase under toxic liver damage and the administration of 6-hydroxy-2,2,4-trimethyl-1,2-dihydroquinoline in rats

Abstract

The study is devoted to clarifying the regulatory and catalytic properties of glutathione peroxidase from liver of rats with toxic liver damage and 6-hydroxy-2,2,4-trimethyl-1,2-dihydroquinoline exposure. The pathology was induced by intragastric administration of carbon tetrachloride at a dose of 0.064 cm3 per 100 g of body weight. The test compound was orally administered at a dose of 50 mg/kg., Animals were divided into 3 groupsduring the experiment: control rats, animals with toxic liver damage, and rats receiving 6-hydroxy-2,2,4-trimethyl-1,2-dihydroquinoline against the background of the pathology. For the purification of glutathione peroxidase from rat liver, chromatographic separation methods with Sephadex G-25 and DEAE-cellulose were used. Glutathione peroxidase activity was measured by a conjugate reaction with glutathione reductase using the Warburg test. The protein content was assessed using the BCA protein assay kit. The results showed that in rats treated with 6-hydroxy-2,2,4-trimethyl-1,2-dihydroquinoline against the background of the pathology induction, the pH optimum and glutathione peroxidase affinity for glutathione were changed in the controldirection. The obtained data may indicate a change in the conformational properties of the enzyme under conditions of a decrease the free radical oxidation intensity under the test compoundaction.
In addition, the introduction of 6-hydroxy-2,2,4-trimethyl-1,2-dihydroquinoline contributed to the normalization of the glutathione peroxidase regulatory properties, to respect toisocitrate, glucose-6-phosphate and Fe2+. Thus, the results of the work indicate the ability of 6-hydroxy-2,2,4-trimethyl-1,2-dihydroquinoline to have a corrective effect on the glutathione peroxidase catalytic and regulatory properties due, apparently, to the antioxidant properties manifestation by this compound.