TP508 mitigates the effects of nuclear radiation on human endothelial cells in culture restoring endothelial NO production, tube formation, and accelerating repair of radiation-induced DNA double-strand breaks. TP508 (50 μg/mL; 24 hours; HCAEC) treatment reverses radiation-induced endothelial dysfunction (ED) and loss of NO signaling by attenuating the downregulation of eNOS expression [1]. TP508 acts as an antagonist for the effects of thrombin. TP508 peptide inhibits these thrombin-induced effects through an RGD and αvβ3-related mechanism [3].

In male CD-1 mice, the treatment of TP508 (10 mg/kg; i.v.) mitigates radiation-induced endothelial cell damage, also significantly increases survival of CD-1 mice when injected 24 h after 8.5 Gy exposure [1].