Inhibition of intimal hyperplasia after stenting by over-expression of p15: A member of the INK4 family of cyclin-dependent kinase inhibitors

• Published in: Journal of molecular and cellular cardiology 2011-03, Vol.50 (3), p.417-425
• Main Authors: Segev, Amit, Nili, Nafiseh, Qiang, Beiping, Osherov, Azriel B, Giordano, Frank J, Jaffe, Ronen, Gauldie, Jack, Sparkes, John D, Fraser, Ashley R, Ladouceur-Wodzak, Michelle, Butany, Jagdish, Strauss, Bradley H
• Format: Article
• Language: English
• Subjects: Adenoviridae - genetics; Animals; beta-Galactosidase - biosynthesis; beta-Galactosidase - genetics; beta-Galactosidase - metabolism; Cardiovascular; Carotid Arteries - metabolism; Carotid Arteries - pathology; Cell cycle; Cell Growth Processes - physiology; Cells, Cultured; Cyclin-Dependent Kinase Inhibitor p15 - biosynthesis; Cyclin-Dependent Kinase Inhibitor p15 - genetics; Cyclin-Dependent Kinase Inhibitor p15 - metabolism; G1 Phase - genetics; Genetic Therapy - methods; Humans; Hyperplasia - etiology; Hyperplasia - metabolism; Hyperplasia - pathology; Muscle, Smooth, Vascular - cytology; Muscle, Smooth, Vascular - metabolism; Muscle, Smooth, Vascular - pathology; p15; Phosphorylation; Rabbits; Rats; Restenosis; Retinoblastoma Protein - metabolism; Smooth muscle cell; Stents - adverse effects; Transduction, Genetic; Transgenes; Tumor suppresor gene; Tunica Intima - metabolism; Tunica Intima - pathology
• ISSN: 0022-2828; 1095-8584
• DOI: 10.1016/j.yjmcc.2010.11.007

Abstract We evaluated the role of p15Ink4 , a member of the INK4 family of CDK inhibitors on vascular smooth muscle cells (VSMCs) proliferation, cell cycle progression and intimal hyperplasia after stenting. Aortic VSMCs transduced with either adenovirus encoding for p15Ink4 or β-galactosidase were assessed for DNA synthesis, cell cycle progression, and pRb phosphorylation. Rabbit carotid arteries were stented and treated with peri-adventitial delivery of saline or adenovirus encoding for p15Ink4 or β-galactosidase. p15Ink4 transgene and protein expression were evaluated at 24 h and 72 h, respectively. In-stent cell proliferation was evaluated by BrdU at day 7. Histomorphometric analysis of in-stent intimal hyperplasia was performed at 10 weeks. Human p15Ink4 DNA was detected in transduced VSMCs at 24 h. p15Ink4 over-expression reduced VSMCs DNA synthesis by 60%. Cell cycle progression was inhibited, with a 30% increase in G1 population accompanied by inhibition of pRb phosphorylation. Human p15Ink4 transgene was identified in transduced stented arteries but not in control arteries. p15Ink4 immunostaining was increased and cell proliferation significantly reduced by 50% in p15Ink4 transduced arteries. Intimal cross-sectional area (CSA) of p15Ink4 -treated group was significantly lower than the β-gal treated and non-transduced groups ( p = 0.008). There were no differences in the intimal or medial inflammatory response between groups. p15Ink4 over-expression blocks cell cycle progression leading to inhibition of VSMCs proliferation. Peri-adventitial delivery of p15Ink4 significantly inhibits in-stent intimal hyperplasia.