title: Modification of aquaporin expression in response to fenretinide-induced transdifferentiation of ARPE-19 cells into neuronal-like cells.
abstract: OBJECTIVE
  The goal of this study was to investigate the modifications of aquaporin (AQP) expression in ARPE-19 cells in response to fenretinide-induced transdifferentiation into neuronal-like cells
  
  
  METHODS
  ARPE-19 cells were treated daily for 7 days with 3 μm fenretinide or dimethyl sulphoxide as control. mRNA and protein expression were evaluated by real-time quantitative PCR, Western blot analysis and immunofluorescence.
  
  
  RESULTS
  Control ARPE-19 cells expressed AQP1, AQP4, AQP6 and AQP11 at the mRNA level, but only AQP4, AQP6 and AQP11 at the protein level. Fenretinide induced the transdifferentiation of ARPE-19 cells into neuronal-like cells. Indeed, fenretinide induced morphological changes similar to neurons characterized by elongated cell body and the formation of neurite branching. Moreover, ARPE-19 cells transdifferentiated to neuron-like cells were characterized by significant decrease in retinal pigmented epithelium markers, for example cytokeratin 8 and cellular retinaldehyde-binding protein, as well as an increase in neuronal markers such as synaptophysin and calretinin. AQP4 expression, at both mRNA and protein levels, and AQP6 expression, only at protein level, were significantly decreased in ARPE-19 cells transdifferentiated into neuronal-like cells.
  
  
  CONCLUSIONS
  The expression of AQP4 and AQP6 is downregulated during fenretinide-induced transdifferentiation.
authors.affiliation: Laboratory of Pathophysiological and Nutritional Biochemistry, Université Libre de Bruxelles, Brussels, Belgium.|Department of Ophthalmology, CHU Saint-Pierre and Brugmann, Brussels, Belgium.
authors.forename: Dany
authors.initials: D
authors.lastname: Salik
authors.affiliation: Laboratory of Pathophysiological and Nutritional Biochemistry, Université Libre de Bruxelles, Brussels, Belgium.|Department of Ophthalmology, CHU Saint-Pierre and Brugmann, Brussels, Belgium.
authors.forename: Elie
authors.initials: E
authors.lastname: Motulsky
authors.affiliation: Laboratory of Pathophysiological and Nutritional Biochemistry, Université Libre de Bruxelles, Brussels, Belgium.
authors.forename: Françoise
authors.initials: F
authors.lastname: Gregoire
authors.affiliation: Laboratory of Pathophysiological and Nutritional Biochemistry, Université Libre de Bruxelles, Brussels, Belgium.
authors.forename: Valérie
authors.initials: V
authors.lastname: Delforge
authors.affiliation: Laboratory of Pathophysiological and Nutritional Biochemistry, Université Libre de Bruxelles, Brussels, Belgium.
authors.forename: Nargis
authors.initials: N
authors.lastname: Bolaky
authors.affiliation: Department of Ophthalmology, CHU Saint-Pierre and Brugmann, Brussels, Belgium.
authors.forename: Laure
authors.initials: L
authors.lastname: Caspers
authors.affiliation: Laboratory of Pathophysiological and Nutritional Biochemistry, Université Libre de Bruxelles, Brussels, Belgium.
authors.forename: Jason
authors.initials: J
authors.lastname: Perret
authors.affiliation: Department of Ophthalmology, CHU Saint-Pierre and Brugmann, Brussels, Belgium.|I.R.I.B.H.M, Brussels, Belgium.
authors.forename: François
authors.initials: F
authors.lastname: Willermain
authors.affiliation: Laboratory of Pathophysiological and Nutritional Biochemistry, Université Libre de Bruxelles, Brussels, Belgium.
authors.forename: Christine
authors.initials: C
authors.lastname: Delporte
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D051401:Aquaporin 4 / Q000235:genetics* / Q000378:metabolism; D051403:Aquaporin 6 / Q000235:genetics* / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism; D015153:Blotting, Western; D002460:Cell Line; D054338:Cell Transdifferentiation / Q000187:drug effects*; D017931:DNA Primers / Q000737:chemistry; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D017313:Fenretinide / Q000494:pharmacology*; D019084:Fluorescent Antibody Technique, Indirect; D005786:Gene Expression Regulation / Q000502:physiology; D006801:Humans; D009474:Neurons / Q000166:cytology*; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D055213:Retinal Pigment Epithelium / Q000166:cytology* / Q000378:metabolism
chemical_list: C496030:AQP4 protein, human; C102226:AQP6 protein, human; D000970:Antineoplastic Agents; D051401:Aquaporin 4; D051403:Aquaporin 6; D015415:Biomarkers; D017931:DNA Primers; D012333:RNA, Messenger; D017313:Fenretinide; D004121:Dimethyl Sulfoxide
keywords: ARPE-19; aquaporin; blood-retinal barrier; fenretinide; retina; transdifferentiation