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The aims of our study were to evaluate the antioxidant defence mechanisms of liver tissue challenged by doxorubucin (DOX) and to compare the possible protective effects of N-acetylcysteine (NAC) (n=10), deferoxamine (DOF) (n=10), DOF+NAC (n= 10) and selenium (n=9) on doxorubicin-induced hepatotoxicity. Fifty-six male rats (Mean weight = 250 ± 50 g) randomly divided into five groups. Animals in study groups were pretreated with a single dose of Dox, which was administered intravenously. Control group (n=7) was treated with intravenous saline injection. Selenium was given intraperitoneally. Blood and urine samples were collected before sacrifice. Liver tissue samples were collected and tissue superoxide dismutase (SOD), glutathione peroxidase (GSH-px), CAT activity, MDA, Zn, iron and copper were determined. DFO decreased lipid peroxidation significantly. DFO and NAC decreased CAT activity significantly. Antioxidant regimes increase SOD activities significantly. DOF and NAC increase GSH-px activities and copper levels significantly. Beneficial effect of selenium seems to result from its stimulation of SOD but not to GSH-px. It has been found that DOF, NAC and selenium have protective effects on Dox-induced hepatocellular damage. DOF+NAC did not result additional benefit.

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Background: Sepsis is a state of augmented oxidative stress and diminished antioxidant capacity. High density lipoprotein (HDL) particles were shown to possess antioxidant and anti-inflammatory properties, as well as Paraoxonase 1 (PON1), which is an enzyme that is also protective against HDL oxidation. Previous studies suggested a possible role of decreased PON1 activity or HDL levels in sepsis patients. Aims: The present study was designed to test a hypothesis that higher PON1 activity and HDL-cholesterol levels could predict a better survival in sepsis patients. Study Design: Observational study. Methods: Venous blood samples were collected from sepsis patients for HDL-cholesterol levels, PON1 activity and cytokine assays (TNF-α and IL-6) and Acute Physiologic and Chronic Health Evaluation II (APACHE II) scores were calculated in order to weight patients' disease severity on the day of sepsis diagnosis. Patients were followed-up until the 28 th day for any cause intrahospital mortality. Data were statistically analyzed for effects of study parameters on patients' survival. Results: In total, 85 patients with sepsis were included in the study. The mean age was 65.2±17.9 years and 48 were male; at the end of the 28-day follow-up period, 46 survived. TNF-α (86.9±10.5 vs 118.6±16.4) and IL-6 levels (906.7±82.7 vs 1323.1±54.3) were significantly higher in non-survivors, while PON1 activity (140.7±42.3 vs 66.7±46.6) and HDL-cholesterol levels (43.6±8.1 vs 34.5±8.9) were significantly higher in survivors (p<0.001 for all). TNF-α (r=-0.763) and IL-6 levels (r=-0.947) showed strong negative correlations, PON1 activity (r=0.644) and HDL-cholesterol levels (r=0.477) showed positive correlations with patient survival (p<0.001 for all). Survival estimates significantly favored TNF-α (Log Rank 59.5, p<0.001) and IL-6 levels (Log Rank 53.2, p<0.001) according to PON1 activity (Log Rank 5.4, p<0.03) and HDL-cholesterol levels (Log Rank 8.3, p<0.005). Regression analyses for relative contributions of parameters to survival showed that higher IL-6 levels (t:-16.489, p<0.001) were the most significant negative factor for survival, and TNF-α levels (t:-4.417, p<0.001), whereas PON1 activity had a positive effect (t:3.210, p<0.003). Conclusion:The present study showed that although low PON1 activity and HDL-cholesterol levels were related to mortality, higher levels were not found to be as predictive as cytokine levels for survival.

Hyperbaric oxygen (HBO) therapy has been shown to attenuate renal ischemia/reperfusion (I/R) injury in rats, when applied in the early reperfusion period. The aim of this study was to elucidate possible beneficial effects of HBO therapy on renal I/R injury, when applied 24 h after ischemia. Rats were randomized into three groups: (1) control group (n ¼ 20), (2) I/R group (n ¼ 20), and (3) I/R þ HBO group (n ¼ 20). Renal I/R injury was created by interrupting renal blood flow for 30 min with a non-traumatic vascular clamp. HBO therapy was administered 24 h after I/R injury and continued for 5 days. At the end of the study, rats were sacrificed under anesthesia, blood was drawn, and right kidneys were harvested for analysis. Renal I/R injury increased serum and tissue malondialdehyde (MDA) levels and reduced superoxide dismutase (SOD) and glutathione peroxidase (GPx) levels. HBO therapy attenuated MDA levels by increasing SOD and GPx activities. HBO therapy also prevented neutrophil infiltration and tissue injury in kidneys. Taken together, HBO therapy has been found to be effective in the delayed period of I/R injury.