title: Molecular mechanism of statin-mediated LOX-1 inhibition.
abstract: Statins are largely used in clinics in the treatment of patients with cardiovascular diseases for their effect on lowering circulating cholesterol. Lectin-like oxidized low-density lipoprotein (LOX-1), the primary receptor for ox-LDL, plays a central role in the pathogenesis of atherosclerosis and cardiovascular disorders. We have recently shown that chronic exposure of cells to lovastatin disrupts LOX-1 receptor cluster distribution in plasma membranes, leading to a marked loss of LOX-1 function. Here we investigated the molecular mechanism of statin-mediated LOX-1 inhibition and we demonstrate that all tested statins are able to displace the binding of fluorescent ox-LDL to LOX-1 by a direct interaction with LOX-1 receptors in a cell-based binding assay. Molecular docking simulations confirm the interaction and indicate that statins completely fill the hydrophobic tunnel that crosses the C-type lectin-like (CTLD) recognition domain of LOX-1. Classical molecular dynamics simulation technique applied to the LOX-1 CTLD, considered in the entire receptor structure with or without a statin ligand inside the tunnel, indicates that the presence of a ligand largely increases the dimer stability. Electrophoretic separation and western blot confirm that different statins binding stabilize the dimer assembly of LOX-1 receptors in vivo. The simulative and experimental results allow us to propose a CTLD clamp motion, which enables the receptor-substrate coupling. These findings reveal a novel and significant functional effect of statins.
authors.affiliation: a Department of Systems Medicine and Center of Biostatistics and Bioinformatics ; University of Rome Tor Vergata ; Rome , Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Biocca
authors.forename: Federico
authors.initials: F
authors.lastname: Iacovelli
authors.forename: Sara
authors.initials: S
authors.lastname: Matarazzo
authors.forename: Giulia
authors.initials: G
authors.lastname: Vindigni
authors.forename: Francesco
authors.initials: F
authors.lastname: Oteri
authors.forename: Alessandro
authors.initials: A
authors.lastname: Desideri
authors.forename: Mattia
authors.initials: M
authors.lastname: Falconi
mesh_terms: D000818:Animals; D001665:Binding Sites; D019556:COS Cells; D002522:Chlorocebus aethiops; D019281:Dimerization; D005456:Fluorescent Dyes / Q000737:chemistry; D057809:HEK293 Cells; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D008077:Lipoproteins, LDL / Q000737:chemistry / Q000378:metabolism; D008148:Lovastatin / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D008856:Microscopy, Fluorescence; D062105:Molecular Docking Simulation; D011485:Protein Binding; D055550:Protein Stability / Q000187:drug effects; D017434:Protein Structure, Tertiary; D051127:Scavenger Receptors, Class E / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*
chemical_list: D005456:Fluorescent Dyes; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D008077:Lipoproteins, LDL; C495137:OLR1 protein, human; D051127:Scavenger Receptors, Class E; C099252:oxidized low density lipoprotein; D008148:Lovastatin
keywords: Ato, atorvastatin; CTLD, C-type lectin-like domain; Cav-1, caveolin-1; DMEM, Dulbecco's modified Eagle's medium; DiI, 1,1′-dioctadecyl-3,3,3′,3′-tetramethyllindocarbocyanine perchlorate; Flu, fluvastatin; HEK, human embryonic kidney; HMG-CoA, 3-hydroxy-3-methylglutaryl coenzyme A; LDL, low-density lipoprotein; LDL-C, low-density lipoprotein-cholesterol; LOX-1 receptor; LOX-1, lectin-like oxidized low-density lipoprotein receptor-1; Lov, lovastatin; Mab, monoclonal antibody; Pra, pravastatin; molecular docking; molecular dynamics simulation; monomer-dimer ratio; ox-LDL, oxidized low-density lipoprotein; statin; substrate recognition