title: Hsp90 and caveolin are key targets for the proangiogenic nitric oxide-mediated effects of statins.
abstract: 3-Hydroxy-3-methylglutaryl (HMG)-coenzyme A reductase inhibitors or statins exert direct beneficial effects on the endothelium in part through an increase in nitric oxide (NO) production. Here, we examined whether posttranslational modifications of the endothelial NO synthase (eNOS) could account for the proangiogenic effects of statins. We used endothelial cells (ECs) isolated from cardiac microvasculature, aorta, and umbilical veins, as well as dissected microvessels and aortic rings, that were cultured on reconstituted basement membrane matrix (Matrigel). Tube or precapillary formation was evaluated after statin treatment, in parallel with immunoblotting and immunoprecipitation experiments. Atorvastatin stimulated NO-dependent angiogenesis from both isolated and outgrowing (vessel-derived) ECs, independently of changes in eNOS expression. We found that in macro- but not microvascular ECs, atorvastatin stabilized tube formation through a decrease in caveolin abundance and its inhibitory interaction with eNOS. We also identified the chaperone protein hsp90 as a key target for the proangiogenic effects of statins. Using geldanamycin, an inhibitor of hsp90 function, and overexpression of recombinant hsp90, we documented that the statin-induced phosphorylation of eNOS on Ser1177 was directly dependent on the ability of hsp90 to recruit Akt in the eNOS complex. Finally, we showed that statin promoted the tyrosine phosphorylation of hsp90 and the direct interaction of hsp90 with Akt, which further potentiated the NO-dependent angiogenic processes. Our study provides new mechanistic insights into the NO-mediated angiogenic effects of statins and underscores the potential of these drugs and other modulators of hsp90 and caveolin abundance to promote neovascularization in disease states associated or not with atherosclerosis.
authors.affiliation: Department of Medicine, University of Louvain Medical School, Brussels, Belgium.
authors.forename: A
authors.initials: A
authors.lastname: Brouet
authors.forename: P
authors.initials: P
authors.lastname: Sonveaux
authors.forename: C
authors.initials: C
authors.lastname: Dessy
authors.forename: S
authors.initials: S
authors.lastname: Moniotte
authors.forename: J L
authors.initials: JL
authors.lastname: Balligand
authors.forename: O
authors.initials: O
authors.lastname: Feron
mesh_terms: D000818:Animals; D000069059:Atorvastatin; D016227:Benzoquinones; D001681:Biological Assay / Q000379:methods; D002417:Cattle; D051242:Caveolin 1; D022461:Caveolins / Q000378:metabolism*; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015870:Gene Expression; D018841:HSP90 Heat-Shock Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D006538:Heptanoic Acids / Q000494:pharmacology; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000494:pharmacology*; D015151:Immunoblotting; D047029:Lactams, Macrocyclic; D051379:Mice; D008955:Models, Cardiovascular; D018919:Neovascularization, Physiologic / Q000187:drug effects*; D009569:Nitric Oxide / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000187:drug effects / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; D010766:Phosphorylation / Q000187:drug effects; D011485:Protein Binding / Q000187:drug effects; D011499:Protein Processing, Post-Translational; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt; D011758:Pyrroles / Q000494:pharmacology; D011809:Quinones / Q000494:pharmacology; D051381:Rats; D014162:Transfection
chemical_list: D016227:Benzoquinones; C495540:CAV1 protein, human; C495541:Cav1 protein, mouse; C495537:Cav1 protein, rat; D051242:Caveolin 1; D022461:Caveolins; D004791:Enzyme Inhibitors; D018841:HSP90 Heat-Shock Proteins; D006538:Heptanoic Acids; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D047029:Lactams, Macrocyclic; D011518:Proto-Oncogene Proteins; D011758:Pyrroles; D011809:Quinones; D009569:Nitric Oxide; D000069059:Atorvastatin; C496314:NOS3 protein, human; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; C496315:Nos3 protein, mouse; C496316:Nos3 protein, rat; C494918:AKT1 protein, human; C494920:Akt1 protein, rat; D017346:Protein Serine-Threonine Kinases; D051057:Proto-Oncogene Proteins c-akt; C001277:geldanamycin