ANTIOXIDANT PROPERTIES OF AMBROXOL

We rested whether Ambroxol, a drug which stimulates the release of sur factant by pneumocytes type II, may also possess antioxidant propertie s. To assess the reactivity of Ambroxol with reactive oxygen species, we analysed its ability to decompose hydrogen peroxide (H2O2) and to i nhibit the superoxide (O-2(.-))-dependent autooxidation of pyrogallol, hydroxyl radical ((OH)-O-.)-mediated deoxyribose oxidation, and hypoc hlorous acid (HClO)-induced chlorination of monochlorodimedon. Ambroxo l was found to be a sufficient scavenger of HClO and (OH)-O-. and also revealed the capacity to decompose H2O2 At concentrations of 25 and 7 0 mu M, it inhibited HClO-induced chlorination of monochlorodimedon by 22 +/- 13 and 59 +/- 14%, respectively. Similarly, at concentrations of 1, 2, and 10 mM, Ambroxol decreased (OH)-O-.-mediated deoxyribose o xidation by 47 +/- 11, 75 +/- 9, and 89 +/- 4%. In addition, at concen trations of 1 to 5 mM, it completely protected linoleic acid from (OH) -O-.-induced peroxidative damage. Ambroxol had a weak effect on O-2(.- )-dependent autooxidation of pyrogallol. Our results indicate that Amb roxol has antioxidant activity, which may have clinical significance i n protecting lung tissue from oxidant-induced injury.