Receptor binding mode and pharmacological characterization of a potent and selective dual CXCR1/CXCR2 non-competitive allosteric inhibitor
Article first published online: 16 DEC 2011
© 2011 The Authors. British Journal of Pharmacology © 2011 The British Pharmacological Society
British Journal of Pharmacology
Volume 165, Issue 2, pages 436–454, January 2012
How to Cite
Bertini, R., Barcelos, L., Beccari, A., Cavalieri, B., Moriconi, A., Bizzarri, C., Di Benedetto, P., Di Giacinto, C., Gloaguen, I., Galliera, E., Corsi, M., Russo, R., Andrade, S., Cesta, M., Nano, G., Aramini, A., Cutrin, J., Locati, M., Allegretti, M. and Teixeira, M. (2012), Receptor binding mode and pharmacological characterization of a potent and selective dual CXCR1/CXCR2 non-competitive allosteric inhibitor. British Journal of Pharmacology, 165: 436–454. doi: 10.1111/j.1476-5381.2011.01566.x
- Issue published online: 16 DEC 2011
- Article first published online: 16 DEC 2011
- Accepted manuscript online: 30 JUN 2011 01:45PM EST
- Received; 31 January 2011; Revised; 26 May 2011; Accepted; 7 June 2011
- chemokine receptors;
- non-competitive allosteric inhibitor;
- binding mode;
- leucocyte recruitment;
- experimental angiogenesis;
- ischaemia reperfusion injury
BACKGROUND AND PURPOSE DF 2156A is a new dual inhibitor of IL-8 receptors CXCR1 and CXCR2 with an optimal pharmacokinetic profile. We characterized its binding mode, molecular mechanism of action and selectivity, and evaluated its therapeutic potential.
EXPERIMENTAL APPROACH The binding mode, molecular mechanism of action and selectivity were investigated using chemotaxis of L1.2 transfectants and human leucocytes, in addition to radioligand and [35S]-GTPγS binding approaches. The therapeutic potential of DF 2156A was evaluated in acute (liver ischaemia and reperfusion) and chronic (sponge-induced angiogenesis) experimental models of inflammation.
KEY RESULTS A network of polar interactions stabilized by a direct ionic bond between DF 2156A and Lys99 on CXCR1 and the non-conserved residue Asp293 on CXCR2 are the key determinants of DF 2156A binding. DF 2156A acted as a non-competitive allosteric inhibitor blocking the signal transduction leading to chemotaxis without altering the binding affinity of natural ligands. DF 2156A effectively and selectively inhibited CXCR1/CXCR2-mediated chemotaxis of L1.2 transfectants and leucocytes. In a murine model of sponge-induced angiogenesis, DF 2156A reduced leucocyte influx, TNF-α production and neovessel formation. In vitro, DF 2156A prevented proliferation, migration and capillary-like organization of HUVECs in response to human IL-8. In a rat model of liver ischaemia and reperfusion (I/R) injury, DF 2156A decreased PMN and monocyte-macrophage infiltration and associated hepatocellular injury.
CONCLUSION AND IMPLICATIONS DF 2156A is a non-competitive allosteric inhibitor of both IL-8 receptors CXCR1 and CXCR2. It prevented experimental angiogenesis and hepatic I/R injury in vivo and, therefore, has therapeutic potential for acute and chronic inflammatory diseases.