Research from the Centre for Vision & Vascular Science at Queen's University, Northern Ireland has reported on the potential therapeutic value of using an erythropoietin (EPO)-derived peptide for treatment of diabetic retinopathy. Despite the established pro-angiogenic effects of EPO with its potential to accelerate proliferative retinopathy, the research group believes that their approach may be capable of isolating the beneficial effects of tissue repair and suppression of inflammation associated with EPO. As such, the research may hold significant promise for clinical use in the treatment of the sight-threatening disorder.

The research used an 11 amino-acid peptide based on the EPO helix-B domain, termed "pHBSP", and delivered the construct by intraperitoneal injection into models of diabetic retinopathy at a dosage of 10ug/kg. The results demonstrated that the treatment had no impact on the hematocrit but was capable of significantly reducing the stress related response in the diabetic retina (p<0.001). In addition, diabetes-linked DNA damage was significantly reduced - up to 49% in the ganglion cell layer when compared to controls, (p<0.05) and acellular capillary formation was blocked. The research demonstrated that treatment with an EPO-derived peptide after diabetes was established was still capable of protecting against neuroglial and vascular degenerative pathology.

The authors of the study argue that the intervention strategy adopted shows that the pHBSP peptide is "highly effective at preventing clinically relevant lesions of diabetic retinopathy without exacerbating neovascularization". As such, the study appears to provide convincing data that the protective beneficial effects of EPO may be capable of being harnessed to slow or block progression of early stage diabetic retinopathy. While the angiogenic characteristics of EPO in the context of diabetic retinopathy may raise a number of concerns, no alteration of the hematocrit was observed and there were no issues of vascular thrombosis or hypertension reported. The benefits from use of pHBSP arose following 28 days of treatment in models that were diabetic for 6 months prior to treatment, further suggesting that clinical application may present a significant pharmaceutical opportunity.

Printed from the EURETINA EyeBrief on 25 May 2013