Identification of CXCR4 inhibitors as a key therapeutic small molecule in renal fibrosis

The final stage of almost all chronic kidney diseases is renal fibrosis. Simple wounds or persistent inflammation can cause tissue inflammation, which, in the case of the kidney, results in scarring. Vascular sclerosis, tubulointerstitial fibrosis and glomerular fibrosis are all types of kidney fibrosis. Renal damage and fibrosis are caused by elevated expression of CXCR4. This study aimed to identify possible pharmacological agents which could bind to and inhibit isoform I of CXCR4 and determine their strength of interactions. The I-TASSER, Galaxyweb and Robetta were used to predict and refine the structure of the CXCR4 protein. ModBase was used to improve the loops, and then the quality was evaluated by using the ERRAT value (92.15) and Ramachandran plot. The improved 3D structure was subjected to small molecule database docking using Maestro (from Schrodinger) and the glide module. GROMACS was used to simulate molecules with the three top low glide scores and the best ADME properties. The best glide score was achieved by ligand ID 4990 (-11.5). Simulations, free energy landscape and residue decomposition analysis revealed that 4990 interacted more consistently with CXCR4 than the other two small molecules.Communicated by Ramaswamy H. Sarma.