Protective Role of Silymarin in Early Doxorubicin-induced Cardiac Dysfunction in Children with Acute Lymphoblastic Leukemia

Background: Doxorubicin is a well-established chemotherapeutic agent for the treatment of childhood acute lymphoblastic leukemia (ALL), but its efficacy is often limited by its related cardiotoxicity. Protection against doxorubicin-induced cardiotoxicity can be of great value, especially for children. Silymarin has a potent antioxidant property that can be helpful in preventing cardio-toxicity. Objective: ‘To assess the possible protective role of silymarin against early doxorubicin-induced cardiotoxicity in children with ALL’. Subjects and Methods: This study was conducted on 80 children with ALL, including 40 patients under doxorubicin therapy and silymarin 420 mg/day for one week after each doxorubicin dose starting from the day of doxorubicin infusion (Group I) and 40 patients under doxorubicin therapy and placebo (Group II). ‘Conventional echo-Doppler measures of left ventricular systolic and diastolic functions and pulsed wave tissue Doppler of lateral mitral annulus were done for all patients’. Results: After doxorubicin therapy, there was a significant higher reduction of systolic function [ejection fraction (EF), fraction shortening (FS) and s wave] in Group II compared with Group I and non-significant reduction of diastolic function [E/A ratio or e/a ratio] in both Groups. Although serum troponin increases in both groups after doxorubicin therapy, the increase of troponin is significantly lower in group I compared with group II. Conclusion: Silymarin decreased early Doxorubicin-induced left ventricular systolic function disturbances and can be recommended as an adjuvant drug in patients with ALL under doxorubicin therapy. Recommendation: ‘Multicenter studies on a large number of patients with longer follow up’ periods to prove the protective role of silymarin in early and late Doxorubicin-induced cardiotoxicity.