Kh Smolle

Oxidative stress: potential of distinct peroxide determination systems.

Abstract When reactive oxygen species attack biological structures, peroxides, which are short-lived oxidative intermediates, are generated. We evaluated the potential of two different, commercially available peroxide activity assays (Pox-Act and d-ROMS) to see whether the results were associated with the clinical condition of subjects who were participating in a routine health care program. Furthermore, we determined the total antioxidant status (TAS) and the titer of autoantibodies against oxidized low-density lipoprotein (oLAb) to verify the hydroperoxide measurements. Subjects with medical conditions (hereafter referred to as patients) had significantly increased serum peroxide levels compared to healthy subjects. The d-ROMS kit indicated that 86% of subjects had an increased level of total peroxides. Although the assays had a significant correlation (p < 0.001), 34% of the subjects had an increased total peroxide concentration in the Pox-Act assay that was clearly associated with clinical symptoms. Furthermore, the sensitivity of the Pox-Act assay was 35 times higher than that of the d-ROMS kit. In subjects with medical conditions, there was a trend toward a decreased TAS and a slightly increased oLAb titer in comparison to healthy subjects, but this was not statistically significant. The Pox-Act assay seems to be a valuable tool for the determination of total peroxides, while the results from the d-ROMS kit should be considered with caution.

Serum Total Peroxides Are Increased in Patients with Stage IV Compared to Stage IIb Peripheral Arterial Disease: Percutaneous Transluminal Angioplasty May Generate Epitopes for Autoantibodies Against Oxidized Low Density Lipoprotein

Abstract Reactive oxygen species are involved, among others, in peripheral arterial disease (PAD). During percutaneous transluminal angioplasty (PTA) vascular walls become damaged, which finally leads to ischemia/reperfusion injury. In PAD patients with Fontaine stage IIb (11 males and 6 females) and with Fontaine stage IV (7 males and 3 females) undergoing revascularisation, we correlated oxidative stress biomarkers, i.e. serum total peroxides and autoantibodies against oxidized LDL (oLAb), with the stage of PAD. Subjects with stage IV disease had significantly higher peroxide levels at baseline compared to stage IIb (510 ± 360 AU vs. 150 ± 220 AU, p < 0.05). Revascularisation was associated with a significant decrease in the oLAb titer (314 ± 240 vs. 251 ± 190 mU/mL, p < 0.05). Total peroxides may indicate the severity of PAD and the time course of oLAb titers could be used as a biomarker for revascularisation.