Formyl Peptide Receptor 1 Inhibits Reparative Angiogenesis and Aggravates Neuroretinal Dysfunction in Ischemic Retinopathy.

PURPOSE

Ischemic retinopathy is the major cause of vision-threatening conditions. Inflammation plays an important role in the pathogenesis of ischemic retinopathy. Formyl peptide receptor 1 (FPR1) has been reported to be implicated in the regulation of inflammatory disorders. However, the role of FPR1 in the progression of ischemic retinal injury has not been fully explained.

METHODS

The activation of FPR1 was measured by real-time PCR and western blotting in the retina of OIR. The effect of FPR1 on the expression of inflammatory cytokines and relevant pro-angiogenic factors was assessed between wild-type and FPR1-deficiency OIR mice. The impact of FPR1 on retinal angiogenesis was evaluated through quantifying retinal vaso-obliteration and neovascularization between and OIR mice. At last, the neuronal effect of FPR1 on the ischemic retina was investigated by ERG between wild-type and FPR1-deficient OIR mice.

RESULTS

The expression of FPR1 significantly increased in the retina of OIR. Furthermore, FPR1 deficiency downregulated pro-inflammatory and pro-angiogenic factors. Ablation of FPR1 suppressed the retinal pathological neovascularization and promoted reparative revascularization, ultimately improving retinal neural function after ischemic injury.

CONCLUSION

In ischemic retinopathy, FPR1 aggravates inflammation and inhibits reparative angiogenesis to exacerbate neuronal dysfunction.