In this study, we investigated the concentration of serum homocysteine (Hcy) in patients with rheumatoid arthritis (RA) compared with the control group and the connection between homocysteine and parameters of inflammation and disease activity. Sixty RA patients and 20 healthy controls were included in the study, and clinical examination and investigation were performed during which disease activity was assessed. Peripheral blood samples were used for all of the assays. Levels of Hcy were 33% higher in the RA patients than in the control subjects (mean +/− SD 11.79±3.72 μmol/L versus 8.90±1.38 μmol/L; p< 0.01). A significant correlation was found between parameters of inflammation (C-reactive protein) and homocysteine in patients (r=0.322, p=0.012). Patients with high disease activity had a significantly greater increase in homocysteine (p<0.05). An increase in plasma homocysteine in RA patients is related to the parameters of inflammation and disease activity. Elevated Hcy levels occur commonly in patients with RA and may explain some of the increased cardiovascular mortality seen in RA patients.

Considering the role of von Willebrand factor (vWf) in hemostasis, and the role of oxidative stress in the development of endothelial dysfunction and atherosclerotic disease, the aim of our study was to investigate the relationship between vWf, parameters of oxidative stress and different types of acute coronary syndromes (ACS). Levels of vWf activity (vWfAct), vWf antigen (vWfAg), nitric oxide (estimated through nitrites–NO2  −), superoxide anion radical (O2  −), hydrogen peroxide (H2O2), index of lipid peroxidation (estimated through thiobarbituric acid reactive substances–TBARS), superoxide dismutase (SOD) and catalase (CAT) activity of 115 patients were compared with those of 40 healthy controls. ACS patients had significantly higher vWfAct and vWfAg levels, as well as TBARS levels, while their levels of NO2  −, H2O2, SOD and CAT activities were lower than controls'. vWfAg showed high specificity and sensitivity as a test to reveal healthy or diseased subjects. Multivariant logistic regression marked only vWfAg and TBARS as parameters that were under independent effect of ACS type. The results of our study support the implementation of vWf in clinical rutine and into therapeutic targets, and suggest that ACS patients are in need of antioxidant supplementation to improve their impaired antioxidant defence.

Our aim was to investigate the relation between fetal distress and oxidative stress. Fetal distress was associated with increased concentration of superoxide in the fetal blood and with significant increase of the level of H2O2 in both maternal and fetal blood. The activity of superoxide dismutase was increased roughly sixfold (p < 0.01) in the maternal [7330 ± 2240 U/g of hemoglobin in controls (C) and 36811 ± 16862 U/g in fetal distress (FD)] and fetal blood (C: 5930 ± 2641 U/g; FD: 41912 ± 17133 U/g). In contrast, fetal distress was related to a considerable decrease of catalase activity in both maternal (C: 26011 ± 8811 U/g; FD: 7212 ± 1270 U/g) and fetal blood (C: 37194 ± 9191 U/g; FD: 6173 ± 1965 U/g). From this we concluded that in fetal distress, the maternal and fetal bloods are exposed to superoxide- and H2O2-mediated oxidative stress, which could be initiated by hypoxic conditions in the fetal blood and placenta. A tremendous increase/decrease of the activities of superoxide dismutase/catalase in the blood of women bearing a distressed fetus in comparison to healthy subjects implies that the assessment of superoxide dismutase/catalase activity could be of use for establishing a timely and accurate ante- or intrapartum diagnosis of fetal distress.

This pilot study could be a starting point for further investigation and possible implementation of some antioxidants in the treatment of portal hypertension.