ABSTRACT
Hypothetical, therapeutic effects of ozone were investigated in an animal model. One ml of oxygen or mixture of 40 micrograms ozone with oxygen were injected intraperitoneally to male rats for 10 days. Previously, rats had been poisoned with 50 ppm Cd2+ in drinking water for 12 weeks. Exhaustive treadmill running was applied to some animals before sacrification. Ozone injections increased iron-ascorbate-stimulated lipid peroxidation (LPO) in the liver and kidney, catalase (CAT) activity in the heart and glutathione S-transferase (GST) activity in the heart, kidney and liver. Oxygen increased GST activity in the brain and reduced glutathione peroxidase (GPX) activity in the kidney. Cadmium enhanced LPO in the liver and GST activity in the brain, heart, kidney and liver. In contrast to ozone, cadmium inhibited GPX activity in the brain, kidney and liver. Cadmium combined with ozone enhanced the changes of GPX activity in the kidney and liver, that of GST activity in the heart, kidney and liver as well as of CAT activity and LPO in kidney. The results suggest that ozone injections combined with tested factors may provoke an oxidative stress. The effects of ozone therapy can not be explained as the results of ozone action on the antioxidative enzymes in rat.
Subject(s)
Antioxidants/metabolism , Catalase/metabolism , Glutathione Peroxidase/metabolism , Glutathione Transferase/metabolism , Lipid Peroxidation/drug effects , Ozone/therapeutic use , Animals , Disease Models, Animal , Male , Rats , Rats, WistarABSTRACT
In vitro generation of thiobarbituric acid reactive substances (TBARS) is frequently used to assess organ susceptibility to lipid peroxidation. The yield of TBARS is severalfold enhanced by an addition of iron ions with reductors or chelators such as ascorbate, NADPH, ADP or pyrophosphate. The process cannot be interpreted in a simple way, since it involves several enzymatic and nonenzymatic reactions. There are no clear interpretations of the ambiguous effects of denaturating factors and chelating agents on TBARS generation. Also controversy arises from the curvilinear relationship between the homogenate concentration and the yield of TBARS. This has been modelled in the present work by combining two functions describing the sequential reaction with two limiting steps. One of them is related to catalytic action of iron and ascorbate, while the other to an enzyme, possibly phospholipase A2, as has been suggested by some investigators. Two models should be considered since it is impossible to decide which kinetic equation should predominate in the model. Nevertheless, the model reflects kinetic properties of the process. The effects of catalyst concentration and some other modification upon the yield of TBARS were also investigated experimentally. The results of experiments and modelling showed that the analytical procedures used by investigators need standardisation as the results obtained under a variety of procedures may reflect quite different properties of the living systems.
