Ghrelin’s effects in diabetic retinopathy: Inhibition of choroid retinal cells migration cultured under a hyperglycemic environment.

Abstract

AbstractPurpose The purpose of this work is to investigate the effect of ghrelin in a primate choroid retinal cell line cultured under hyperglycemic conditions and its effect on the early changes of diabetic retinopathy in an animal model of type1 diabetes mellitus (DM1).Methods A RF/6a cell line was used in the in vitro assay. Cell migration was assessed using the wound healing assay under increasing (0‐300mM) glucose concentrations. To test its effect, ghrelin was added (10‐5‐10‐10nM) to the cell cultures for 24h. Positive controls had VEGF added to the medium. For the in vivo studies, diabetic Wistar rats received intravitreal injections of either ghrelin (81nM) or saline every 4 weeks for 3 months. Vascular permeability was assessed using the Evans blue assay.Results Increasing concentrations of glucose show a reduction in cell migration distance. We defined 10 mM of glucose as the basal and 250 mM as the hyperglycemic condition. At a concentration of 10‐8 nM ghrelin potentiates the reduction of migration induced by the hyperglycemic medium, and reduces the migration induced by VEGF. Regarding the in vivo model, diabetic animals treated with intravitreal ghrelin injections showed no alteration in vascular permeability, when compared with diabetic controls.Conclusion Ghrelin reduces cell migration in choroid‐retinal cells under hyperglycemic media, but appears to have no effect on the vascular permeability in a DM1 animal model.