Effects of Selol 5% supplementation on the activity or concentration of antioxidants and malondialdehyde level in the blood of healthy mice.

BACKGROUND Selol is a novel organoselenium Se(IV) compound. It reveals lower potential of toxicity than sodium selenite and does not exhibit mutagenic activity. Its antioxidant and anticancer properties including overcoming cancer cell resistance to standard therapy of the drug were proven. This is the first publication describing the influence of Selol 5% on the activity of blood antioxidant status in vivo. MATERIALS AND METHODS We investigated the influence of Selol 5% short-term (24h) and long-term (28 days) administration on the activity of antioxidant enzymes, including the main selenoenzymes, in healthy mice plasma and erythrocytes. Plasma oxygen radical absorbance capacity value (ORAC) and the concentration of malonyldialdehyde (MDA) in plasma as a biomarker of oxidative stress as well as the value of selenium (Se) concentration in erythrocytes were shown. RESULTS A significant increase of the selenium dependent glutathione peroxidase (Se-GSHPx) activity in plasma and erythrocytes, plasma selenoprotein P concentration, ORAC values, and Se concentration were observed during long-term supplementation as well as after Selol 5% single-dose administration, with two distinct increases of activity a few hours after the beginning of the experiment and before its end. We found a decreased thioredoxin reductase (THRR) activity and an increased MDA level during Selol 5% long-term supplementation. Glutathione S-transferase activity (GST) remained unchanged. CONCLUSION Selol 5% supplementation in vivo affects the selenoenzymes activities as well as the antioxidant status of plasma and erythrocytes. Selol 5% is an inhibitor of thioredoxin reductase activity, which can be important in anticancer therapy.