Caffeic acid modulates CREB activation protecting from oxidative-stress induced senescence in retinal pigment epithelial cells

MARQUIONI-RAMELLA MD; MARAZITA M; TATE P; SUBURO AM

Mar del Plata

Congreso; LX REUNIÓN CIENTÍFICA ANUAL Sociedad Argentina de Investigación Clínica.; 2016

Age related macular degeneration (AMD) is a progressive disease which leads to irreversible loss of vision. Premature cellular senescence of the retinal pigmented epitelium (RPE) is suggested to play a central role in the etiology of AMD. Polyphenols, micronutrients present in our diet, are postulated to protect against degenerative diseases development. We have previously reported that oxidative damage, a hallmark of AMD, promotes cellular senescence in RPE cells. In addition, Caffeic acid (CAF, a polyphenol) prevented senescence induction in RPE. We now aimed to determine the signaling pathways involved in CAF mediated protection. We hypothesized that CAF modulates cAMP-response element binding protein (CREB) activation leading to reduce ROS levels and prosurvival pahtways activation. Retinal pigment epithelial cells (ARPE-19 cell line), were incubated or not with caffeic acid (12,5 μg/ml) for 2 hours and then exposed to H2O2 (150μM) for 90 minutes. Cells were collected at different time points following damage. CREB activation and BCL-2 expression were analized by Western blot. Reactive oxygen species (ROS) levels were detected using DCFH-diacetate fluorescent probe and flow-cytometry. Phosphorylation of CREB (CREB- S133) was increased (p < 0,05) at 4 and 24 h in CAF samples compared to H2O2 damaged cells without CAF. ROS levels were significatly decreased (p < 0,05) by CAF treatment at 24 h. Conversely, BCL-2 pro-survival factor was enhanced (p < 0,05) at 4 and 24 h by CAF. Conclusions: CAF mediated CREB activation might impact on downstream effectors, decreasing oxidative damage and promoting survival and proliferation, consequently, limiting induction of cellular senescence in RPE cells.