In this study we assessed activities of antioxidant enzymes, lipid peroxidation end-products, and nitric oxide (NO) levels in women with postmenopausal osteoporosis (PMO). Relationship between oxidative stress parameters and NO levels with bone mineral density (BMD) and clinical variables influencing bone mass and health related quality of life measures was also investigated in women with PMO. Postmenopausal women (n=87), aged 40-65, without previous diagnosis or treatment for osteoporosis and independent in daily living activities were included. BMD was measured at the lumbar spine and proximal femur using dual-X-ray absorptiometry (DXA). Erythrocyte catalase (CATe) enzyme activity, erythrocyte and plasma enzyme activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and lipid peroxidation end-product malondialdehyde (MDA) and nitrite/nitrate levels, by product of NO were studied. A total of 23 healthy non-porotic women were included as controls. Women with PMO had significantly lower erythrocyte CATe enzyme activity and higher erythrocyte malondialdehyde (MDAe) and erythrocyte nitric oxide (NOe) levels in comparison to controls whereas erythrocyte SODe and GSH-Px enzyme activity was similar. In plasma, osteoporotic women had significantly higher SOD enzyme activity and higher MDA levels whereas similar GSH-Px enzyme activity and NO levels compared to non-porotic controls. Significant correlation was found between erythrocyte SODe, CATe enzyme activity and NOe levels with proximal femur BMD. Some of the quality of life scores as pain, mental, and social functions correlated with antioxidant enzyme activities and NO levels.Consequently, oxidative stress markers may be an important indicator for bone loss in postmenopausal women. Further researches assessing the oxidative stress markers and NO in bone tissue and changes with anti-osteoporotic drugs would be valuable to better understand the role of free radicals, antioxidants, and NO in the regulation of bone mass.

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Hepatic ischemia-reperfusion (I/R) injury may be developed in some conditions, such as trauma, major hepatic resection, hemorrhagic shock or liver transplantation. I/R injury of the liver causes hepatocellular damage that may lead to hepatic failure. A considerable body of evidence indicates that reactive oxygen species (ROS) and inflammation may contribute to hepatocellular injury in liver I/R. Leflunomide is an isoxazole derivative, and a unique immunomodulatory agent. In the present study, we examined the effects of leflunomide on the neutrophil activation with oxidative stress and some antioxidant enzymes in the reperfusion following I/R in the rat liver. Thirty-two rats divided into four groups: group 1 (control); was given leflunomide 10 mg/kg, i.g.; group 2 (SHAM), animals were only laparotomized; group 3 (liver I/R), and group 4 (liver I/R + Leflunomide). In group 4, rats were pretreated with leflunomide (10 mg/kg, i.g.) two doses prior to experiment. In groups 3 and 4, occluding the hepatic pedicel for 60 min induced ischemia and reperfusion was allowed thereafter for 60 min. At the end of the reperfusion period, rats were sacrificed. superoxide dismutase, catalase, nitric oxide, xanthine oxidase, malondialdehyde, protein carbonyl and myeloperoxidase levels were determined in hepatic tissue as well as histological examination with H and E staining. Group 3 animals demonstrated severe deterioration of liver morphology and a significant liver oxidative stress. Pretreatment of animals with leflunomide markedly attenuated morphological alterations and neutrophil activation, reduced elevated oxidative stress products levels and restored the depleted hepatic antioxidant enzyme. The findings imply that ROS play a causal role in I/R-induced hepatic injury, and leflunomide exerts hepatoprotective effects probably by the anti-inflammatory effect with radical scavenging and antioxidant activities.

The purpose of this study was to test whether sulfasalazine has a protective action against interstitial inflammation and the development of renal fibrosis in obstructive nephropathy. Female rats were subjected to a sham (n = 10) or unilateral ureteral obstruction (UUO, n = 30). UUO was induced in rats by ligating the left ureter. Three days after operation, rats subjected to UUO were randomized to receive tretment with either sulfasalazine (100 mg/kg) or vehicle every day for the last 7 days of the experiment. At 10 days following UUO, the obstructed kidney exhibited tubulointerstitial injury and leukocyte infiltration (mainly monocytes) that were associated with high levels of reactive oxygen species, cytokines, transforming growth factor (TGF)-beta1, myeloperoxidase (MPO), and lipid peroxidation. Ten days after UUO, the obstructed kidney was also associated with increased nuclear factor kappa beta (NF-kappabeta) expression in saline-treated rats. Compared with sham-operated rats, UUO rat kidneys showed lower concentrations of antioxidant enzymes in the obstructed kidney tissue. All of these changes were significantly attenuated by treatment with sulfasalazine in the obstructed kidney. Sulfasalazine protected against the renal interstitial inflammation and tissue damage elicited by ureteral occlusion. Inhibition of the NF-kappabeta-dependent pathway and inflammatory response and oxidative stress inhibition is likely to be involved in the beneficial effects of sulfasalazine.

Aim: This study is designed to investigate the protective effects of propolis in ocular tissues against chronic alcohol exposure. Material and Method: Wistar albino rats were used in this study. Rats were divided into 4 groups, and each group was fed a special liquid diet which contained an equal amount of calories. The control group was fed the liquid special diet without alcohol and propolis. We added propolis (150 mg/kg) to the diet of the second group. The diet of the third group contained alcohol, the concentration of which was increased progressively. The fourth group was fed a diet including propolis and alcohol. To counterbalance caloric intake, we decreased the amount of glucose in the special liquid diet for groups 3 and 4. At the end of 30 days, the animals were sacrificed and samples were kept at –80°C until evaluation. Specimens were investigated by light microscopy for morphology and morphometry. Results: In the histological investigation of ocular tissues, alcohol caused an increase in thickness of the cornea and corneal epithelium compared to the control group (p < 0.05). This incremental tendency was significantly reduced by propolis, and values were very close to those of the control group (p > 0.05). Alcohol did not cause any significant alteration of rat retinal thickness. Conclusion: This study showed that propolis is highly effective against corneal edema secondary to chronic alcohol intake.