Alterations in antioxidant defense system of workers chronically exposed to arsenic, cadmium and mercury from coal flying ash.

Humans are exposed to different stress factors that are responsible for over-production of reactive oxygen species. Exposure to heavy metals is one of these factors. The aim of the study was to analyze the effect of chronic exposure to heavy metals through coal flying ash on the efficiency of antioxidative defensive mechanisms, represented by the activity of superoxide dismutase, glutathione peroxidase and ascorbic acid. Nonessential elements such as arsenic and mercury levels showed a significant increase (p > 0.001) in the power plant workers rather than in the control subjects. There were no significant differences of blood cadmium between power plant workers and control subjects. We found a significant positive correlation (p < 0.05) between BAs/SZn (r = 0.211), BAs/BSe (r = 0.287), BCd/SCu (r = 0.32) and BHg/BSe (r = 0.263) in the plant workers. Red blood cell antioxidant enzymes and plasma ascorbic acid were significantly lower in power plants workers than in the control group (p < 0.002). We can conclude that levels of mercury, arsenic and cadmium in blood, despite their concentration within the reference values, significantly affect plasma ascorbic acid concentration, superoxide dismutase and glutathione peroxidase activity, which are able to increase the risk of oxidative stress.

Correlation of Inflammation and Lipoprotein (a) with Hypercoagulability in Hemodialysis Patients.

BACKGROUND: Inflammatory and procoagulant markers are potential mediators for the cardiovascular risk in hemodialysis patients. Lipoprotein (a) [Lp(a)], is another important risk factor with inflammatory and procoagulant effects. MATERIALS AND METHODS: In 78 hemodialysis patients and 40 controls, C-reactive protein (CRP), Interleukin-6 (IL-6), lipoprotein (a) [Lp (a)], fibrinogen, D-dimer, von Wilebrand factor (vWF) and serum albumin were determined. RESULTS: CRP, IL-6, Lp(a), fibrinogen, D-dimer and vWF, were significantly higher, and serum albumin was significantly lower in patients compared to controls (24.40 mg/L vs. 6.39 mg/L, p<0.001; 1.92 pg/ml vs. 0.35 pg/ml, 28.05 mg/dL vs.16.25 mg/dL, p<0.001; 3.44 g/L vs. 2.55 g/L, p<0.01; 1.81 µgFEU /ml vs. 0.50 µgFEU /ml, p<0.01; 152.9 % vs. 85.6 %, p<0.001; 32.1 g/L vs. 40.50 g/L, p<0.001). The patients were divided into two groups: 40 patients with CRP levels over than 10 mg/L and 38 with CRP levels in normal range. These parameters showed significant differences between patients with elevated CRP and patients with normal CRP levels. CRP and IL-6 correlated positively with Lp(a), (r = 0.62, p < 0.001; r=0.54, p<0.001), fibrinogen, (r = 0.63, p < 0.001; r = 0.49, p<0.01) D dimer (r = 0.72, p<0.001; r = 0.55, p<0.01), vWF (r = 0.76, p<0.01; r = 0.63, p<0.001) and negatively with serum albumin (r = -0.80, p<0.01; r = -0.60, p<0.001), in patients with elevated CRP, but not in patients with normal CRP levels and controls. CONCLUSION: According to the results hemodialysis patients with increased inflammatory markers, have the elevated Lp(a) and procoagulant markers and the greater risk for atherosclerotic cardiovascular disease.