Genistein ameliorates adverse cardiac effects induced by arsenic trioxide through preventing cardiomyocytes apoptosis

Abstract

Background/Aims: Arsenic trioxide (As 2 O 3 ) is a highly effective agent for treatment of acute promyelocytic leukemia (APL). However, consecutively administered As 2 O 3 induces serious adverse cardiac effects, including long QT syndrome (LQTs) and even sudden cardiac death. Previous studies have shown that genistein (Gen) exerts anti-oxidant, anti-inflammatory, and anti-apoptotic effects. The present study aimed to explore the potential protective effects of Gen on As 2 O 3 -induced adverse cardiac effects, and to elucidate the underlying molecular mechanisms. Methods: A rat model of As 2 O 3 -induced QT prolongation was generated by intravenous injection with As 2 O 3 . Surface electrocardiogram (ECG) and hemodynamics were employed to assess the LQTs and cardiac function. Intracellular calcium concentration ([Ca 2+ ] i ) and mitochondrial membrane potential (Δψm) were measured by confocal microscopy, and cardiomyocytes apoptosis were assessed by TUNEL assay. Western blot was applied to determine protein levels. Results: We found for the first time that treatment with Gen significantly reversed LQTs and dose-dependently improved As 2 O 3 -induced impairment of cardiac function. As 2 O 3 elevated [Ca 2+ ] i and Gen mitigated this effect. Meanwhile, Gen significantly reversed As 2 O 3 -mediated cardiomyocytes apoptosis. Furthermore, Gen dose-dependently inhibited the phosphorylated JNK and p38-MAPK (pp38-MAPK), and blocked Δψm collapse, and further decreased cleaved caspase-3. Conclusion: Gen protects against the adverse cardiac effects of As 2 O 3 partly by mitigating cardiomyocytes apoptosis induced by As 2 O 3 through attenuating intracellular calcium overload and downregulating protein expression of p-JNK and pp38-MAPK to ameliorate the damage of Δψm leading to suppression of caspase-3 activation. Gen might be used as an adjunction therapy in APL patients receiving As 2 O 3 treatment to avoid, at least to minimize, the adverse cardiac effects of As 2 O 3 . Copyright © 2013 S. Karger AG, Basel.