High-throughput screening system for identifying phototoxic potential of drug candidates based on derivatives of reactive oxygen metabolites.

PURPOSE

The present study aimed to develop a high-throughput screening strategy for predicting the phototoxic potential of pharmaceutical substances, using a derivatives-of-reactive-oxygen-metabolites (D-ROM) assay.

METHODS

The assay conditions of the D-ROM assay were optimized with a focus on screening run time, sensitivity, solvent system, and reproducibility. The phototoxic potentials of 25 model compounds were assessed by the D-ROM assay, as well as by other screening systems for comparison, including the reactive oxygen species (ROS) assay, the DNA-photocleavage assay, and the 3T3 neutral red uptake phototoxicity test (3T3 NRU PT).

RESULTS

Some phototoxic drugs tended to yield D-ROM when exposed to simulated sunlight (250 W/m(2)), whereas D-ROM generation was negligible for non-phototoxic chemicals. Compared with the ROS assay, the assay procedure for the D-ROM assay was highly simplified with a marked reduction in screening run time. Comparative experiments also demonstrated that D-ROM data were related to the outcomes of the DNA-photocleavage assay and the 3T3 NRU PT, with prediction accuracies of 76 and 72%, respectively.

CONCLUSION

The D-ROM assay has potential for identifying the phototoxic potential of a large number of new drugs as a 1st screening system in the early stages of drug discovery.