Inhibition of oxygen-induced ischemic retinal neovascularization with adenoviral 15-lipoxygenase-1 gene transfer via up-regulation of PPAR-γ and down-regulation of VEGFR-2 expression

PLoS One. 2014 Jan 21;9(1):e85824. doi: 10.1371/journal.pone.0085824. eCollection 2014.

Abstract

15-lipoxygenase-1 (15-LOX-1) plays an important role in angiogenesis, but how it works still remains a controversial subject. The aims of our study are focused on determining whether or not 15-LOX-1 inhibiting oxygen-induced ischemic retinal neovascularization (RNV) and the underlying regulatory mechanism involving of 15-LOX-1, peroxisome proliferator-activated receptor γ (PPAR-γ) and vascular endothelial growth factor receptor 2 (VEGFR-2) in oxygen-induced retinopathy (OIR). Recombinant adenoviral vectors that expressing the 15-LOX-1 gene (Ad-15-LOX-1-GFP) or the green fluorescence protein gene (Ad-GFP) were intravitreous injected into the OIR mice at postnatal day 12 (P12), the mice were sacrificed 5 days later (P17). Retinal 15-LOX-1 expression was significantly increased at both mRNA and protein levels after 15-LOX-1 gene transfer. Immunofluorescence staining of retinal sections revealed 15-LOX-1 expression was primarily in the outer plexiform layer (OPL), inner nuclear layer (INL) and ganglion cell layer (GCL) retina. Meanwhile, RNV was significantly inhibited indicated by fluorescein retinal angiography and quantification of the pre-retinal neovascular cells. The expression levels of PPAR-γ were significantly up-regulated while VEGFR-2 were significantly down-regulated both in mRNA and protein levels. Our results suggested 15-LOX-1 gene transfer inhibited RNV in OIR mouse model via up-regulation of PPAR-γ and further down-regulation of VEGFR-2 expression. This could be a potentially important regulatory mechanism involving 15-LOX-1, PPAR-γ and VEGFR-2 during RNV in OIR. In conclusion, 15-LOX-1 may be a new therapeutic target for treating neovascularization diseases.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenoviridae / metabolism
  • Animals
  • Arachidonate 15-Lipoxygenase / genetics
  • Arachidonate 15-Lipoxygenase / therapeutic use*
  • Disease Models, Animal
  • Down-Regulation / genetics*
  • Female
  • Genetic Therapy
  • Ischemia / genetics
  • Ischemia / pathology
  • Ischemia / therapy*
  • Mice
  • Mice, Inbred C57BL
  • Oxygen
  • PPAR gamma / genetics*
  • PPAR gamma / metabolism
  • Retina / metabolism
  • Retina / pathology
  • Retinal Neovascularization / genetics
  • Retinal Neovascularization / pathology
  • Retinal Neovascularization / therapy*
  • Up-Regulation / genetics*
  • Vascular Endothelial Growth Factor Receptor-2 / genetics*
  • Vascular Endothelial Growth Factor Receptor-2 / metabolism

Substances

  • PPAR gamma
  • Arachidonate 15-Lipoxygenase
  • Vascular Endothelial Growth Factor Receptor-2
  • Oxygen

Grants and funding

This study was funded by the National Natural Science Foundation of China (81000393; 81000395; 81270998; 302-164172). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.