Effects of water-soluble antioxidant from spinach, NAO, on doxorubicin-induced heart injury

Doxorubicin (DOX) produces clinically restorative responses innumerous huma n cancers, butits cardiotoxicity has limited its usefulness. Because reacti ve oxygen species may affect DOX-induced antitumor activity and cardiotoxic ity, we evaluated the prophylactic effect of spinach natural antioxidant (N AO) on DOX-induced cardiotoxicity and oxidative stress in female Balb/c mic e using histological, electron microscopical and biochemical parameters. Mi ce were treated with NAO for 7 days prior to and/or for 6 days after DOX ad ministration. Pretreatment with NAO (cumulative dose: 130 mg/kg) did not hi nder the effectiveness of DOX. Light and electron microscopy of DOX-treated heart revealed myocardial degeneration. When administered combined before and after DOX, NAO conferred the most significant cardiac protection. The e ffects of NAO on the lipid peroxidation product, malondialdehyde, and on H2 O2/hydroperoxides were examined on day 6 following DOX administration; leve ls of both were elevated in DOX-treated mice, compared to control. Pretreat ment with NAO prevented these changes. Pretreatment with NAO before DOX adm inistration decreased catalase and increased superoxide dismutase activitie s compared to the DOX group. Our results suggest usage of NAO in combinatio n with DOX as a prophylactic strategy to protect heart muscle from DOX-indu ced cellular damage.