STUDIES ON THE BIOLOGICAL EFFECTS OF OZONE - 7 - GENERATION OF REACTIVE OXYGEN SPECIES (ROS) AFTER EXPOSURE OF HUMAN BLOOD TO OZONE

The acceptance of any complementary medical approach is conditioned by the results obtained after the same scientific scrutiny applied in or thodox medicine. Otherwise any claim of efficacy remains in the realm of fiction. In the case of ozone therapy, the mechanisms of action hav e remained nebulous and in a series of publications we are trying to p resent the biochemical, immunological and morphological evidence in fa vour or against ozone therapy. We have now shown that ozone (O-3) diss olved in the water of either plasma or serum or physiological saline g enerates reactive oxygen species (ROS), of which hydrogen peroxide (H2 O2) can be unequivocally demonstrated by using specific methods for it s detection. Lipids present in plasma preferentially, those present in lipoproteins, undergo peroxidation that is somewhat O-3-dose dependen t and can be observed by the measurement of thiobarbituric acid reacti ve substances (TBARS). While the generation of H2O2 is crucial in acti vating both biochemical (hexose monophosphate shunt) and immunological (via the transcription factor NF-kB) mechanisms, the role of lipid ox idation products (LOP) remains to be investigated We have shown here t hat there is a small brit consistent induction of some cytokines (TNF- alpha, IFN-gamma and IL-2) were human blood is directly exposed to O-3 concentrations up to 100 mu g/ml per g of blood. On rite other hand i solated blood mononuclear cells (PBMC) in tissue culture medium are fa r more sensitive to the oxidant action of O-3 as shown by a progressiv e reduction of the proliferation index with comparatively far lower O- 3, concentrations On the whole, these results support the concept that much of the O-3 toxicity is neutralized by the powerful antioxidant s ystem of blood. The minimal hemolysis supports this idea but as far as platelets are concerned,we must mention that they tend to aggregate i n heparinized blood even when it is exposed to an O-3 concentration of 40 mu g/ml. In spite of the lack of side-effects after autohemotherap y, this drawback must be kept in mind and avoided in clinical practice .