Electroporation-mediated delivery of catalytic oligodeoxynucleotides for manipulation of vascular gene expression

1 Division of Pulmonary and Critical Care Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611; and 2 Department of Pharmacology, Physiology, and Therapeutics, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota 58203 Submitted 14 April 2003 ; accepted in final form 18 July 2003 The development of inexpensive and effective approaches to transiently decrease gene expression in vivo would be useful for the study of physiological processes in living animals. DNAzymes are a novel class of DNA oligonucleotides that can catalytically cleave target mRNAs and thereby reduce protein production. However, current methods for their delivery in vivo are limited and inefficient. In this study, we show that electroporation can be used to deliver DNAzymes to the intact mesenteric vasculature of rats. With the use of PKC- as a target, a set of wild-type and mutant control DNAzymes was designed and shown to reduce both PKC- mRNA and protein levels in cultured smooth muscle cells in a specific manner. The wild-type DNAzyme reduced PKC- protein levels by 70% at 24 h in two different cell lines without decreasing the levels of the five other PKC isoforms tested. When delivered to the intact vasculature using electroporation, the DNAzyme reduced PKC- protein levels by >60% without affecting these other PKC isoforms. Electroporation was required for oligonucleotide transfer and was able to deliver the DNAzymes to multiple cell layers in the vessel wall. Protein levels were reduced maximally by 24 h postelectroporation and returned to normal by 48 h. These results suggest that electroporation can be used to deliver DNAzymes and other DNA oligonucleotides to the vasculature in vivo and can decrease gene expression for a window of time that can be used for experimental studies. DNAzyme; protein kinase C- ; transient knockout; gene delivery Address for reprint requests and other correspondence: D. A. Dean, Div. of Pulmonary and Critical Care Medicine, Feinberg School of Medicine, Northwestern Univ., 303 E. Chicago Ave., Tarry 14-707, Chicago, IL 60611 (E-mail: dean{at}northwestern.edu ).