Ozone oxidative preconditioning is a prophylactic approach, which favors the antioxidant-prooxidant balance for preservation of cell redox state by the increase of antioxidant endogenous systems in both in vivo and in vitro experimental models. Our aim is to analyze the effect of ozone oxidative preconditioning on serum TNF-α levels and as a modulator of oxidative stress on hepatic tissue in endotoxic shock model (mice treated with lipopolysaccharide (LPS)). Ozone/oxygen gaseous mixture which was administered intraperitoneally (0.2, 0.4, and 1.2 mg/kg) once daily for five days before LPS (0.1 mg/kg, intraperitoneal). TNF-α was measured by cytotoxicity on L-929 cells. Biochemical parameters such as thiobarbituric acid reactive substances (TBARS), enzymatic activity of catalase, glutathione peroxidase, and glutathione-S transferase were measured in hepatic tissue. One hour after LPS injection there was a significant increase in TNF-α levels in mouse serum. Ozone/oxygen gaseous mixture reduced serum TNF-α levels in a dose-dependent manner. Statistically significant decreases in TNF-α levels after LPS injection were observed in mice pretreated with ozone intraperitoneal applications at 0.2 (78%), 0.4 (98%), and 1.2 (99%). Also a significant increase in TBARS content was observed in the hepatic tissue of LPS-treated mice, whereas enzymatic activity of glutathion-S transferase and glutathione peroxidase was decreased. However in ozone-treated animals a significant decrease in TBARS content was appreciated as well as an increase in the activity of antioxidant enzymes. These results indicate that ozone oxidative preconditioning exerts inhibitory effects on TNF-α production and on the other hand it exerts influence on the antioxidant-prooxidant balance for preservation of cell redox state by the increase of endogenous antioxidant systems.

Ozone oxidative preconditioning is a prophylactic approach, which favors the antioxidant-prooxidant balance for preservation of the cell redox state by increasing antioxidant endogenous systems in both in vivo and in vitro experimental models. The aim of this study was to analyze the effect of ozone oxidative preconditioning on the level of tumor necrosis factor-alpha (TNF-alpha) in the serum of mice treated with lipopolysaccaride (LPS). Pretreatment with an ozone/oxygen gaseous mixture was administered intraperitoneally (0.2, 0.4 and 1.2 mg/kg) or by rectal application (0.2 and 0.4 mg/kg) once daily during five days before LPS (0.1 mg/kg, intraperitoneal). TNF-alpha was measured by cytotoxicity on L-929 cells. One hour after LPS injection, a significant mean increase of TNF-alpha in mouse serum was observed. Ozone/oxygen gaseous mixture reduced serum TNF-alpha levels in a dose-dependent manner. Statistically significant decreases in TNF-alpha levels after LPS injection were observed either with ozone intraperitoneal applications at 0.2 (78 %), 0.4 (98.5 %) and 1.2 (98.6 %) mg/ kg or by rectal application at 0.2 (46.2 %) and 0.4 (97.4 %) mg/kg. These results indicate that ozone oxidative preconditioning inhibits TNF-alpha production.