Background: The role of oxygen free radicals is considered important in the development of cardiovascular disease. However, until recently determination of free radicals plasma levels and the effect of antioxidant therapy on these levels has been difficult. The aim of the study was to determine the oxidative stress and the effect of the antioxidant compound AR(D) Stenovit on this stress in normal subjects and patients with intermittent claudication after oral administration for one week.
Methods: A portable, free radicals (FRs) determination system (D-Roms test, Diacron, Grosseto, Italy) was used. This test is based on the ability of transition metals to catalyse in the presence of peroxides with formation of FRs which are trapped by an alchilamine. The alchilamine reacts forming a coloured radical detectable at 505 nm. The reagents utilised are the cromogen (R1, an alchilamine) and a pH 4.8 buffer (R2). Ten microl of hemolysis-free serum are to 1 ml of R2 and to 10 microl of R1. The sample is mixed, incubated (1 min; 37 degrees C) and read for optical density. After another minute, the sample is read again. The average delta A/min is multiplied by a K factor and calculated using serum with defined value.
Results: In normal subjects the mean (+/-SD) levels of free radicals were 312+/-49 U.CARR (Carratelli units) before treatment and 218+/-33 U.CARR after treatment (p<0.05). A decrease of at least 10% was detected in every subject. In patients with peripheral vascular disease the mean (+/-SD) levels of free radicals were 404+/-42 U.CARR before treatment and 278+/-33 U.CARR after treatment (p<0.02). A decrease of at least 15% was detected in every patient (medium value 31%).
Conclusions: The D-Roms test provides a simple, inexpensive and practical method to identify subjects with a high level of oxidative stress and to demonstrate the effect of treatment. The compound AR(D) Stenovit is effective in reducing circulating free radicals. Its action on the progression of atherosclerotic disease should be assessed in future studies.