Inhibition of in vitro VEGF expression and choroidal neovascularization by synthetic dendrimer peptide mediated delivery of a sense oligonucleotide

Autor: M. Brankov, Istvan Toth, P. Elizabeth Rakoczy, Bradley G. Thomas, Norbert Wimmer, Philip Kearns, Robert J. Marano
Rok vydání: 2004
Předmět:
Zdroj: Experimental Eye Research. 79:525-535
ISSN: 0014-4835
DOI: 10.1016/j.exer.2004.06.023
Popis: Ocular neovascularisation is the leading cause of blindness in developed countries and the most potent angiogenic factor associated with neovascularisation is vascular endothelial growth factor (VEGF). We have previously described a sense oligonucleotide (ODN-1) that possesses anti-human and rat VEGF activity. This paper describes the synthesis of lipid-lysine dendrimers and their subsequent ability to delivery ODN-1 to its target and mediate a reduction in VEGF concentration both in vitro and in vivo. Positively charged dendrimers were used to deliver ODN-1 into the nucleus of cultured D407 cells. The effects on VEGF mRNA transcription and protein expression were analysed using RT-PCR and ELISA, respectively. The most effective dendrimers in vitro were further investigated in vivo using an animal model of choroidal neovascularisation (CNV). All dendrimer/ODN-1 complexes mediated in a significant reduction in VEGF expression during an initial 24 hr period (40-60%). Several complexes maintained this level of VEGF reduction during a subsequent, second 24 hr period, which indicated protection of ODN-1 from the effects of endogenous nucleases. In addition, the transfection efficiency of dendrimers that possessed 8 positive charges (x=81.51%) was significantly better (P=0.0036) than those that possessed 4 positive charges (x=56.8%). RT-PCR revealed a correlation between levels of VEGF protein mRNA. These results indicated that the most effective structural combination was three branched chains of intermediate length with 8 positive charges such as that found for dendrimer 4. Dendrimer 4 and 7/ODN-1 complexes were subsequently chosen for in vivo analysis. Fluorescein angiography demonstrated that both dendrimers significantly (P
Databáze: OpenAIRE