Discovery of Novel Marine-Derived Phidiandine/Lipoic Acid Hybrid as a Potential Anti-Atherosclerosis Agent: Design, Synthesis and in Vitro/in Vivo Evaluation

In the present study, a novel derivative, IOP-LA, was prepared by hybridizing antioxidant lipoic acid (LA) and our recently reported antioxidative marine phidianidine B-inspired indole/1,2,4-oxadiazole derivative. Our results demonstrated that IOP-LA could protect vascular endothelial cells (VECs) from oxidized low-density lipoprotein (oxLDL)-induced oxidative stress by activating the Nrf2 pathway, inhibit the production of atherosclerotic plaque, and promote the stability of atherosclerotic plaque in apoE(-/-) mice. Moreover, the protective effect of IOP-LA was superior to LA at the same concentration. Mechanistic studies revealed that IOP-LA significantly inhibited the increase of reactive oxygen species (ROS) levels and the translocation of nuclear factor kappa-B (NF-kappa B) nuclear induced by oxLDL through the nuclear factor erythroid2-related factor 2 (Nrf2) pathway. In summary, the data demonstrate that IOP-LA, as a new antioxidant, protects VECs from oxLDL-induced oxidative stress by activating the Nrf2 pathway. It is worth noting that this study provides a promising lead compound for the prevention and treatment of atherosclerosis.