Dexrazoxane HCl (ICRF-187, ADR

Dexrazoxane (10 mM), known clinically to limit anthracycline cardiac toxicity, prevents daunorubicin-induced myocyte apoptosis, but not necrosis induced by higher anthracycline concentrations in rat cardiac myocytes. ^[1] Dexrazoxane presumably exerts its cardioprotective effects by either binding free or loosely bound iron, or iron complexed to doxorubicin, thus preventing or reducing site-specific oxygen radical production that damages cellular components. ^[2] Dexrazoxane specifically abolishes the DNA damage signal gamma-H2AX induced by doxorubicin, but not camptothecin or hydrogen peroxide, in H9C2 cardiomyocytes. Dexrazoxane also induces rapid degradation of Top2beta, which paralleles the reduction of doxorubicin-induced DNA damage. Dexrazoxane antagonizes doxorubicin-induced DNA damage through its interference with Top2beta, which could implicate Top2beta in doxorubicin cardiotoxicity. ^[3] Dexrazoxane is hydrolyzed to its active form intracellularly and binds iron to prevent the formation of superhydroxide radicals, thus preventing mitochondrial destruction. ^[4]