Retinal pigment epithelium signaling in a cellular model of diabetic retinopathy

TENCONI, P.E.; VALLÉS, A.S.; GIUSTO, N.M.; SALVADOR, G.A.; MATEOS, M.V.

Mar del Plata

Congreso; LI Reunion Anual de SAIB; 2015

SAIB

Diabetic retinopathy (DR) is one of the leading causes of visual dysfunction and blindness. The aim of the present work was to set up an in vitro DR model and to study signaling events elicited by high glucose (HG) concentrations in the retinal pigment epithelium (RPE).ARPE-19 cells (human RPE cell line) were exposed to HG (16.5 and 33 mM) and to normal glucose (5 mM, NG) concentrations for 4 and 72 h in order to mimic a peak of and a sustained hyperglycemia. Osmotic controls were performed with mannitol. After 72 h of incubation, cell viability, evaluated by MTT reduction assay, was reduced by 30% in HG conditions with respect to NG. On the contrary, RPE cell viability was not affected in the osmotic controls. Western blot assays showed activation of the extracellular signal-regulated kinase (ERK1/2) and phosphorylation of protein kinase C α/βII (PKCα/βII) after 4 h exposure to both HG concentrations. Furthermore, immunocytochemistry assays showed that HG (33 mM) induced ERK1/2 and the nuclear transcription factor-κB (NF-κB) nuclear translocation.RPE is essential for the integrity and function of the retina and, in consequence, minor changes in cell viability could lead to photoreceptor damage and vision loss in vivo. Thus, elucidating HG effects in this retinal tissue could have potential implications in the discovery of new therapeutic targets for DR treatment.