CLASTOGENIC ACTIVITY IN THE PLASMA OF SCLERODERMA PATIENTS - A BIOMARKER OF OXIDATIVE STRESS

Background: Scleroderma patients exhibit increased chromosomal instabi lity due to circulating clastogenic plasma factors (CP). Formation and action mechanisms of CF are mediated by superoxide, in addition, prev ious work detected inosine triphosphate (ITP) in the plasma of 2 patie nts, and the enzyme adenosine deaminase (ADA) was found to be increase d, Objective: To study correlations between CF, ITP and ADA levels, CF and disease activity, as well as other biomarkers of oxidative stress , Methods: Clastogenic activity was, evaluated by means of cytogenetic methods in 48 patients and 55 healthy subjects. ITP was detected by m ass spectrometry and electrospray ionisation, ADA was measured with a colorimetric assay and malondialdehyde using the Yagi method, Results: Clastogenic activity was significantly increased in patients' plasma compared to controls, In 10 patients CE ITP and ADA were studied simul taneously, All three parameters were increased in the 7 patients of su bgroups 2 (skin and esophagus involvement) and 3 (skin plus multiple o rgan involvement), ITP was not detected in 2 patients of subgroup 1 (s kin involvement only) with low ADA and CF values, Conclusion: ITP, the deamination product of ATP, is one of the clastogenic and superoxide generating components of CE The formation of this deamination product of ATP is probably related to the increase in ADA, CF are biomarkers o f oxidative stress and can be used for evaluation of antioxidant treat ments in scleroderma.