Inhibition of vein graft stenosis with a c-jun targeting DNAzyme in a cationic liposomal formulation containing 1,2-dioleoyl-3-trimethylammonium propane (DOTAP)/1,2- Citation

Background/Objectives—Coronary artery bypass grafting (CABG) is among the most commonly performed heart surgical procedures for the treatment of ischemic heart disease. Saphenous vein graft failure due to stenosis impedes the longer-term success of CABG. A key cellular event in the process of vein graft stenosis is smooth muscle cell (SMC) hyperplasia. In this study, we evaluated the effect of a DNAzyme (Dz13) targeting the transcription factor c-Jun in a rabbit model of vein graft stenosis after autologous transplantation in a cationic liposomal formulation containing 1,2-dioleoyl-3-trimethylammonium propane (DOTAP)/1,2-dioleoyl-snglycero-3-phosphoethanolamine (DOPE). Dz13 in DOTAP/DOPE has undergone preclinical toxicological testing, and a Phase I clinical trial we recently conducted in skin cancer patients demonstrates that it is safe and well tolerated after local administration. Methods—Effects of Dz13 in a formulation containing DOTAP/DOPE on SMC growth and cJun expression were assessed. Dz13 transfection was determined by cellular uptake of carboxyfluorescein-labeled Dz13. Autologous jugular vein to carotid artery transplantation was performed in New Zealand White rabbits to investigate the effect of the Dz13 in DOTAP/DOPE formulation on the extent of intimal hyperplasia. Results—Dz13/DOTAP/DOPE reduced SMC proliferation and c-Jun protein expression in vitro compared with an impotent form of Dz13 bearing a point mutation in its catalytic domain (Dz13.G>C). The Dz13 (500 μg)/DOTAP/DOPE formed lipoplexes that were colloidally stable for up to 1 hour on ice (0°C) or 30 minutes at 37°C, allowing sufficient uptake by the veins. Dz13 (500μg) inhibited neointima formation 28 days after end-to-side transplantation. *Address for correspondence: Levon M. Khachigian, PhD, DSc, Centre for Vascular Research, University of New South Wales, Sydney, NSW 2052, Australia, Tel: +61-2-9385 2537, Fax: +61-2-9385 1797, [email protected]. Author Contributions YL performed the work, analyzed the data and wrote the manuscript; RB designed part of the research and wrote the manuscript; LMK designed and directed the research and wrote the manuscript. LMK is an Australia Fellow of the NHMRC. Disclosures UNSW has IP interests in Dz13. NIH Public Access Author Manuscript Int J Cardiol. Author manuscript; available in PMC 2014 March 13. Published in final edited form as: Int J Cardiol. 2013 October 9; 168(4): 3659–3664. doi:10.1016/j.ijcard.2013.05.092. N IH PA Athor M anscript N IH PA Athor M anscript N IH PA Athor M anscript Conclusions—This formulation applied to veins prior to transplantation may potentially be useful in efforts to reduce graft failure.