Viscum album L. and Quercetin Reduce Cyclophosphamide-Induced Toxicity in Mice

Cyclophosphamide (CP) is an alkylating agent and its tumor cell-killing activity is mainly due to its DNA alkylation. Phosphoramide mustard and acrolein are the two active metabolites of CP. CP metabolites can react with carboxyl (-C[O]OH), mercapto (-SH), amino (-NH2), phosphate (-PO3H2) and hydroxyl (-OH) groups, and can form cross-links with DNA and proteins (Todorova et al., 2009). The precise mechanism by which CP causes toxicity is unknown; however numerous studies have shown that CP exposure can disrupt the redox balance of tissues, suggesting that biochemical and physiological disturbances may result from oxidative stress. Accordingly, the toxic effects of CP on cardiac tissues (Mythili et al., 2005; Senthilkumar et al., 2006; Todorova et al., 2009; Motawi et al., 2010; Nagi et al., 2010) and hemorrhagic cystitis (Bhatia et al., 2006; Linares-Fernández and Alfieri, 2007; Bhatia et al., 2008; Arafa, 2009; Motawi et al., 2010; Santos et al., 2010) were demonstrated in different animal models. Furthermore, in somatic cells, CP has been shown to produce gene mutations, DNA-strand