Migration of retina glial cells requires the synthesis of ceramide-1-phosphate

SIMON M.V.; VERA M; PRADO SPALM F.H.; ROTSTEIN N.P.

Buenos Aires

Congreso; II Reunión Conjunta de Sociedades de Biociencias; 2017

SAIC-SAIB-SAA-SAFE-SAB-SAFIS-SAH-SAI-SAP

MIGRATION OF RETINA GLIAL CELLS REQUIRES THE SYNTHESIS OF CERAMIDE-1-PHOSPHATE.Retina proliferative diseases are major causes of visual dysfunction. Müller glial cells (MGC), the major glial cell type in the retina, and retinal pigment epithelial (RPE) cells play a key role in these diseases. Injuries to the retina exacerbate their proliferation and migration that contribute to visual loss. The molecular cues involved in these processes are still ill defined. We demonstrated that a sphingolipid, sphingosine-1-phosphate (S1P), promotes glial migration. We now investigated whether ceramide-1-phosphate (C1P), which controls proliferation and migration in certain cell types, participates in glial and RPE cell migration. We evaluated migration in primary glial cultures, prepared from newborn rat retinas, and in a RPE cell line (ARPE19), by the wound repair assay. Addition of 10 μM C1P doubled MGC migration. To investigate whether C1P synthesis was required for glial migration, we first established by PCR that MGC expressed ceramide kinase (CerK), the enzyme catalyzing C1P synthesis. NVP231, a CerK inhibitor, completely prevented glial migration, which was not restored by C1P addition. Noteworthy, ARPE19 cell migration was also inhibited by NVP231. We then investigated the signaling pathways involved in C1P effect. Inhibiting the PI3K and the ERK/MAPK pathways, with LY294002 and U0126, respectively, decreased glial migration, both in control and C1P-treated cultures. SP6000, a Jun K inhibitor, also blocked C1P-induced glial migration. C1P activates a cytoplasmic phospholipase A2 (cPLA2) in different cell types. Pre-treatment with ATK, a cPLA2 inhibitor, markedly reduced glial migration in control and C1P-treated cultures.These results show that C1P promotes glial migration through the activation of cPLA2 and the Jun K, the PI3K and the ERK/MAPK pathways. They also imply that exogenous C1P promotes C1P endogenous synthesis to stimulate glial and epithelial cell migration, supporting C1P as a central cue for regulating migration in these cells.