Inhibitory efficacy of hypoxia-inducible factor 1α short hairpin RNA plasmid DNA-loaded poly (D, L-lactide-co-glycolide) nanoparticles on choroidal neovascularization in a laser-induced rat model

Abstract

The aim of this study was to evaluate the possibility of poly (D, L-lactide-co-glycolide) nanoparticle (NPs) as a gene vector for functional plasmid DNA (pDNA) and to investigate its inhibitory efficacy on experimental choroidal neovascularization (CNV). We developed intravitreal administered, hypoxia-inducible factor 1a (HIF-1a) short hairpin RNA and green fluorescent protein (GFP) co-expressed pDNA-loaded NPs (pshHIF-1a NPs). CNV was induced by laser photocoagulation in 112 rats. The rats were then randomly assigned to be injected intravitreally with phosphate-buffered saline (PBS), blank NPs, naked pDNA, control pDNA NPs and pshHIF-1a NPs, respectively, and non-injection group was set as the control. Immunofluorescence staining, fluorescein fundus angiography and histologic analysis were performed to evaluate the inhibitory efficacy on CNV. The results showed that the expression of GFP preferentially localized in the retinal pigment epithelium cell layer and lasted for 4 weeks. The fluorescein leakage areas of CNV were significantly larger in the PBS, blank NPs, control pDNA NPs, non-injection group and naked pDNA group than in pshHIF-1a NPs group (Po0.01). The mean thickness of the CNV lesions in the intravitreally pshHIF1a NPs-treated group was significantly smaller than other groups (Po0.01). No signs of functional or ultrastructural destruction in retina were detected. Therefore, pshHIF-1a NPs may act as a novel therapeutic option to transfer specific pDNA and inhibit the formation of experimental CNV.

Retinal angiogenesis suppression through small molecule activation of p53

“…Laser-induced choroidal neovascularization (CNV) is an established model of pathologic ocular angiogenesis (16). Hif-1α and VEGF protein expression are significantly increased in CNV lesions, and it is conceivable that Nutlin-3-mediated antiangiogenesis also occurs through Hif-1α (17). We performed a single intravitreal injection of racemic Nutlin-3 or DMSO immediately after laser injury and demonstrated that, after 7 days, Nutlin-3 inhibits pathologic retinal angiogenesis in a dosedependent fashion, with peak effect at 10 ng/μl (17.2 μM) (Figure 8, A and B).…”

The Importance of Hypoxia-Regulated, RPE-Targeted Gene Therapy for Choroidal Neovascularization

“…Increased levels of HIF-1 have also been found in CNV lesions from both AMD patients and laser-induced CNV (Vinores et al 2006 ;Zhang et al 2007 ;Sheridan et al 2009 ) . Zhang et al have shown that inhibition of HIF-1 by shRNA can effectively reduce VEGF-induced neovascularization in the laser model (Zhang et al 2010 ) . Also, Vinores et al described that removal of the HRE (the binding site for HIF-1) from the VEGF promoter resulted in a tenfold reduction in the size of laser-induced CNV lesions in mice (Vinores et al 2006 ) .…”

Therapeutic face of RNAi:in vivochallenges

“…A mature platform in development of different versions of silencing is viroid that target specific cell lines. Adeno-associated viruses, adenoviruses (e.g., Ad5), retroviruses (e.g., MoMLV and lentiviruses) and herpes simplex virus are among widely used viral vectors [98,99]. Lentiviral and adenoviral let7 antagomiRs (also known as blockmirs or anti-miRs) has been used to target NSCLC through intranasal delivery methods in murine [73,100].…”