Bixin and lycopene modulation of free radical generation induced by cisplatin–DNA interaction

This work evaluated the modulation of reactive oxygen species (ROS) produced by the cisplatin–human DNA interaction in a cell-free experimental model by the carotenoids bixin and lycopene, extracted from natural dietary sources and purified through luminol- and Cypridina luciferin methoxy-analogue (MCLA)-enhanced chemiluminescence assays. The results showed that the ROS generation by DNA–cisplatin interaction was inhibited by both lycopene and bixin in a concentration-dependent manner. At a concentration of 100 μM, lycopene and bixin inhibited superoxide anion (O2-) generation at 90% and 82%, respectively, and the total ROS generation at 44% and 42%, respectively. The formation of significant amounts of isomers or degradation products of both carotenoids was not observed after ROS scavenging, as evaluated by high-performance liquid chromatography. Taken together, these results suggest that carotenoids can be helpful to modulate the oxidative stress found in cancer therapy with cisplatin.