Discovery of a New Inhibitor of Myeloid Differentiation 2 from Cinnamamide Derivatives with Anti-Inflammatory Activity in Sepsis and Acute Lung Injury.
Chen G, Zhang Y, Liu X, Fang Q, Wang Z, Fu L, Liu Z, Wang Y, Zhao Y, Li X, Liang G.
Acute inflammatory diseases, including acute lung injury and sepsis, remain the most common life-threatening illness in intensive care units worldwide. Cinnamamide has been incorporated in several synthetic compounds with therapeutic potentials including anti-inflammatory properties. However, the possible mechanism and direct molecular target of cinnamamides for their anti-inflammatory effects were rarely investigated. In this study, we synthesized a series of cinnamamides and evaluated their anti-inflammatory activities. The most active compound, 2i, was found to block LPS-induced MD2/TLR4 pro-inflammatory signaling activation in vitro and to attenuate LPS-caused sepsis and acute lung injury in vivo. Mechanistically, we demonstrated that 2i exerts its anti-inflammatory effects by directly targeting and binding MD2 in Arg90 and Tyr102 residues and inhibiting MD2/TLR4 complex formation. Taken together, this work presents a novel MD2 inhibitor, 2i, which has the potential to be developed as a candidate for the treatment of sepsis, and provides a new lead structure for the development of anti-inflammatory agents targeting MD2.