Statins Augment Vascular Endothelial Growth Factor Expression in Osteoblastic Cells via Inhibition of Protein Prenylation

• Published in: Endocrinology (Philadelphia) 2003-02, Vol.144 (2), p.681-692
• Main Authors: Maeda, Toyonobu, Kawane, Tetsuya, Horiuchi, Noboru
• Format: Article
• Language: English
• Subjects: Animals; Atorvastatin; Biological and medical sciences; Bone Morphogenetic Protein 2; Bone Morphogenetic Proteins - genetics; Calcification, Physiologic - drug effects; Cell activation; Cell culture; Cell Line; Cerivastatin; Cholesterol; Cholesterol - metabolism; Coenzyme A; Electrophoretic mobility; Endothelial Growth Factors - genetics; Endothelial Growth Factors - secretion; Fundamental and applied biological sciences. Psychology; Gene expression; Gene Expression - drug effects; Growth factors; Hydrophobicity; Hydroxymethylglutaryl-CoA reductase; Hypolipidemic Agents - pharmacology; Hypoxia; Intercellular Signaling Peptides and Proteins - genetics; Intercellular Signaling Peptides and Proteins - secretion; Kinases; Lymphokines - genetics; Lymphokines - secretion; Metabolites; Mice; Mineralization; Molecular Sequence Data; mRNA stability; Osteoblastogenesis; Osteoblasts; Osteoblasts - cytology; Osteoblasts - physiology; Osteoblasts - secretion; Osteosarcoma; Osteosarcoma cells; Pravastatin; Protein biosynthesis; Protein Prenylation - drug effects; Proteins; Reductases; Regulatory sequences; RNA, Messenger - analysis; Simvastatin; Simvastatin - pharmacology; Skeleton and joints; Skull - cytology; Statins; Stromal cells; Transcription activation; Transcriptional Activation - drug effects; Transforming Growth Factor beta; Vascular endothelial growth factor; Vascular Endothelial Growth Factor A; Vascular Endothelial Growth Factors; Vertebrates: osteoarticular system, musculoskeletal system
• ISSN: 0013-7227; 1945-7170
• DOI: 10.1210/en.2002-220682

Statins such as simvastatin are 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors that inhibit cholesterol synthesis. We presently investigated statin effects on vascular endothelial growth factor (VEGF) expression in osteoblastic cells. Hydrophobic statins including simvastatin, atorvastatin, and cerivastatin–but not a hydrophilic statin, pravastatin–markedly increased VEGF mRNA abundance in nontransformed osteoblastic cells (MC3T3-E1). Simvastatin (10−6 m) time-dependently augmented VEGF mRNA expression in MC3T3-E1 cells, mouse stromal cells (ST2), and rat osteosarcoma cells (UMR-106). According to heterogeneous nuclear RNA and Northern analyses, 10−6 m simvastatin stimulated gene expression for VEGF in MC3T3-E1 cells without altering mRNA stability. Transcriptional activation of a VEGF promoter-luciferase construct (−1128 to +827), significantly increased by simvastatin administration. As demonstrated by gel mobility shift assay, simvastatin markedly enhanced the binding of hypoxia-responsive element-protein complexes. These results indicate that the stimulation of the VEGF gene by simvastatin in MC3T3-E1 cells is transcriptional in nature. VEGF secretion into medium was increased in MC3T3-E1 by 10−6 m simvastatin. Pretreating MC3T3-E1 cells with mevalonate or geranylgeranyl pyrophosphate, a mevalonate metabolite, abolished simvastatin-induced VEGF mRNA expression; manumycin A, a protein prenylation inhibitor, mimicked statin effects on VEGF expression. The effect of simvastatin was blocked by pretreatment with wortmannin and LY294002, specific phosphatidylinositide-3 kinase inhibitors. Simvastatin enhanced mineralized nodule formation in culture, whereas coincubation with mevalonate, geranylgeranyl pyrophosphate, LY294002, or VEGF receptor 2 inhibitor (SU1498) abrogated statin-induced mineralization. Thus, statins stimulate VEGF expression in osteoblasts via reduced protein prenylation and the phosphatidylinositide-3 kinase pathway, promoting osteoblastic differentiation.