Metabonomic study on the cumulative cardiotoxicity of a pirarubicin liposome powder

Pirarubicin (THP) is an anthracycline frequently used in the chemotherapy against acute leukemia, malignant lymphoma and several solid tumors. However, its clinical use is severely limited by the development of a progressive dose-dependent cardiomyopathy that results in irreversible congestive heart failure. To provide a strategy for constraining or minimizing the cumulative cardiotoxicity of THP, a pirarubicin liposome powder (L-THP) was appropriately prepared, and the cumulative cardiotoxicity of L-THP and free THP (F-THP) were investigated on Sprague-Dawley rats after 3 successive doses. Urinary samples for metabonomic study, serum samples for biochemical assay, and heart samples for histopathology test were collected. As a result, the metabonomics-based findings such as PLS-DA plotting showed minimal metabolic alterations in L-THP as compared to F-THP, and correlated with the changes of serum biochemical assay and cardiac histopathology as measurements of damage to heart tissue. Our results confirm that when encapsulated into liposomes, the cumulative cardiotoxicity of THP can be greatly ameliorated. Lipophilic aglycone metabolites of THP associated with redox cycling are cardiotoxic for the possibility of reactive oxygen species (ROS) formation. Also, metabonomic analysis shows that the successive doses of THP will lead to severe metabolic pathways disturbances in the cell energy production. Further, the preliminary efficacy study of L-THP on lung cancer was evaluated in the approach of in vitro cytotoxicity on A549 cells by high content screening (HCS) analysis, and L-THP was found to exhibit better therapeutic index against lung cancer than THP.