Effects on the reactive oxygen species of erdosteine and its metabolite in vitro.

Erdosteine (CAS 84611-23-4) and its active metabolite (M1) decrease the luminol-dependent chemiluminescence (LDCL). In this study, the scavenging effects of erdosteine and M1 on each reactive oxygen species, hypochlorous acid (HOCl), hydrogen peroxide (H2O2) and superoxide anion (O2-), were investigated. M1 interacted with HOCl at high activity, whereas erdosteine exhibited low activity. Although erdosteine interacted with H2O2 only at 1 mmol/l, M1 could significantly decrease H2O2 (> 0.1 mmol/l). Erdosteine and M1 did not interact with O2-. These results suggest that M1 possesses scavenging activities against H2O2 and HOCl in vitro.