title: Inhibition of serotonin-induced mitogenesis, migration, and ERK MAPK nuclear translocation in vascular smooth muscle cells by atorvastatin.
abstract: The HMG-CoA reductase inhibitors, statins, have pleiotropic effects which may include interference with the isoprenylation of Ras and Rho small GTPases. Statins have beneficial effects in animal models of pulmonary hypertension, although their mechanisms of action remain to be determined. Serotonin [5-hydroxytryptamine (5-HT)] is implicated in the process of pulmonary artery smooth muscle (PASM) remodeling as part of the pathophysiology of pulmonary hypertension. We examined the effect of atorvastatin on 5-HT-induced PASM cell responses. Atorvastatin dose dependently inhibits 5-HT-induced mitogenesis and migration of cultured bovine PASM cells. Inhibition by atorvastatin was reversed by mevalonate and geranylgeranylpyrophosphate (GGPP) supplement, suggesting that the statin targets a geranylgeranylated protein such as Rho. Concordantly, atorvastatin inhibits 5-HT-induced cellular RhoA activation, membrane localization, and Rho kinase-mediated phosphorylation of myosin phosphatase-1 subunit. Atorvastatin reduced activated RhoA-induced serum response factor-mediated reporter activity in HEK293 cells, indicating that atorvastatin inhibits Rho signaling, and this was reversed by GGPP. While 5-HT-induced ERK MAP and Akt kinase activation were unaffected by atorvastatin, 5-HT-induced ERK nuclear translocation was attenuated in a GGPP-dependent fashion. These studies suggest that atorvastatin inhibits 5-HT-induced PASM cell mitogenesis and migration through targeting isoprenylation which may, in part, attenuate the Rho pathway, a mechanism that may apply to statin effects on in vivo models of pulmonary hypertension.
authors.affiliation: Pulmonary and Critical Care Division, Tupper Research Institute, Tufts-New England Medical Center, Boston, MA 02111, USA.
authors.forename: Min
authors.initials: M
authors.lastname: Li
authors.forename: Yinglin
authors.initials: Y
authors.lastname: Liu
authors.forename: Parmesh
authors.initials: P
authors.lastname: Dutt
authors.forename: Barry L
authors.initials: BL
authors.lastname: Fanburg
authors.forename: Deniz
authors.initials: D
authors.lastname: Toksoz
mesh_terms: D000818:Animals; D000069059:Atorvastatin; D002417:Cattle; D002455:Cell Division / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects; D002467:Cell Nucleus / Q000201:enzymology; D002478:Cells, Cultured; D004247:DNA / Q000096:biosynthesis; D004347:Drug Interactions; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D006538:Heptanoic Acids / Q000494:pharmacology*; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000494:pharmacology*; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D007668:Kidney / Q000166:cytology; D008798:Mevalonic Acid / Q000494:pharmacology; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D011106:Polyisoprenyl Phosphates / Q000494:pharmacology; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D011651:Pulmonary Artery / Q000166:cytology; D011758:Pyrroles / Q000494:pharmacology*; D012701:Serotonin / Q000494:pharmacology*; D018490:Serotonin Agents / Q000494:pharmacology*; D026362:Serum Response Factor / Q000378:metabolism; D054460:rho-Associated Kinases; D020742:rhoA GTP-Binding Protein / Q000378:metabolism
chemical_list: D006538:Heptanoic Acids; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D047908:Intracellular Signaling Peptides and Proteins; D011106:Polyisoprenyl Phosphates; D011758:Pyrroles; D018490:Serotonin Agents; D026362:Serum Response Factor; D012701:Serotonin; D004247:DNA; D000069059:Atorvastatin; D017346:Protein Serine-Threonine Kinases; D051057:Proto-Oncogene Proteins c-akt; D054460:rho-Associated Kinases; D048049:Extracellular Signal-Regulated MAP Kinases; D020742:rhoA GTP-Binding Protein; C002963:geranylgeranyl pyrophosphate; D008798:Mevalonic Acid