title: Uptake and esterification of vitamin A by RCS rat retinal pigment epithelial cells in primary culture.
abstract: We investigated the capacity of Royal College of Surgeons (RCS) rat retinal pigment epithelial (RPE) cells to take up all-trans-retinol (ROL) (vitamin A) and to metabolize it into retinyl esters (RE). Cultures of RPE cells were established from RCS and control newborn rats. All-trans-ROL was delivered to the apical surface of the RPE monolayer. Retinoids were analyzed by high-performance liquid chromatography. The cellular retinol-binding protein type I (CRBP-I) was assessed by Western blotting. Before supplementation with ROL, RE were lower in RCS rats. After ROL supplementation, esters increased and reached values that were similar in the two strains, but the increase, expressed relative to the initial value, was higher in RCS rats. The uptake of ROL and the level of CRBP-I were greater in RCS rats. Our results provide evidence of a functional retinol esterifying enzyme in cultured RCS RPE cells and suggest that CRBP-I could play a role in the uptake and esterification of ROL in the RPE cells.
authors.affiliation: Laboratoire de Biophysique Sensorielle, Facultés de Médecine et de Pharmacie, Université d'Auvergne, Clermont-Ferrand, France. cia@st-antoine.inserm.fr
authors.forename: David
authors.initials: D
authors.lastname: Cia
authors.forename: Brigitte
authors.initials: B
authors.lastname: Bonhomme
authors.forename: Véronique
authors.initials: V
authors.lastname: Azaïs-Braesco
authors.forename: Jacques
authors.initials: J
authors.lastname: Cluzel
authors.forename: Michel
authors.initials: M
authors.lastname: Doly
mesh_terms: D000818:Animals; D015153:Blotting, Western / Q000379:methods; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004847:Epithelial Cells / Q000378:metabolism*; D004951:Esterification; D010857:Pigment Epithelium of Eye / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D012177:Retinol-Binding Proteins / Q000032:analysis; D054840:Retinol-Binding Proteins, Cellular; D014212:Tretinoin / Q000032:analysis / Q000378:metabolism* / Q000494:pharmacology
chemical_list: D012177:Retinol-Binding Proteins; D054840:Retinol-Binding Proteins, Cellular; D014212:Tretinoin