title: Fatp1 deficiency affects retinal light response and dark adaptation, and induces age-related alterations.
abstract: FATP1 is involved in lipid transport into cells and in intracellular lipid metabolism. We showed previously that this protein interacts with and inhibits the limiting-step isomerase of the visual cycle RPE65. Here, we aimed to analyze the effect of Fatp1-deficiency in vivo on the visual cycle, structure and function, and on retinal aging. Among the Fatp family members, we observed that only Fatp1 and 4 are expressed in the control retina, in both the neuroretina and the retinal pigment epithelium. In the neuroretina, Fatp1 is mostly expressed in photoreceptors. In young adult Fatp1(-/-) mice, Fatp4 expression was unchanged in retinal pigment epithelium and reduced two-fold in the neuroretina as compared to Fatp1(+/+) mice. The Fatp1(-/-) mice had a preserved retinal structure but a decreased electroretinogram response to light. These mice also displayed a delayed recovery of the b-wave amplitude after bleaching, however, visual cycle speed was unchanged, and both retinal pigment epithelium and photoreceptors presented the same fatty acid pattern compared to controls. In 2 year-old Fatp1(-/-) mice, transmission electron microscopy studies showed specific abnormalities in the retinas comprising choroid vascularization anomalies and thickening of the Bruch membrane with material deposits, and sometimes local disorganization of the photoreceptor outer segments. These anomalies lead us to speculate that the absence of FATP1 accelerates the aging process.
authors.affiliation: Inserm U1051, Institute for Neurosciences of Montpellier, CHU St Eloi, Montpellier, France.
authors.forename: Karim
authors.initials: K
authors.lastname: Chekroud
authors.forename: Laurent
authors.initials: L
authors.lastname: Guillou
authors.forename: Stephane
authors.initials: S
authors.lastname: Grégoire
authors.forename: Gilles
authors.initials: G
authors.lastname: Ducharme
authors.forename: Emilie
authors.initials: E
authors.lastname: Brun
authors.forename: Chantal
authors.initials: C
authors.lastname: Cazevieille
authors.forename: Lionel
authors.initials: L
authors.lastname: Bretillon
authors.forename: Christian P
authors.initials: CP
authors.lastname: Hamel
authors.forename: Philippe
authors.initials: P
authors.lastname: Brabet
authors.forename: Marie O
authors.initials: MO
authors.lastname: Pequignot
mesh_terms: D000375:Aging / Q000235:genetics* / Q000502:physiology; D000818:Animals; D017931:DNA Primers / Q000235:genetics; D003623:Dark Adaptation / Q000235:genetics / Q000502:physiology*; D004596:Electroretinography; D050612:Fatty Acid Transport Proteins / Q000172:deficiency / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism; D005453:Fluorescence; D006652:Histological Techniques; D008027:Light; D051379:Mice; D018345:Mice, Knockout; D046529:Microscopy, Electron, Transmission; D016133:Polymerase Chain Reaction; D012160:Retina / Q000378:metabolism / Q000528:radiation effects* / Q000648:ultrastructure; D055213:Retinal Pigment Epithelium / Q000378:metabolism; D012243:Rhodopsin / Q000378:metabolism; D018709:Statistics, Nonparametric; D019745:cis-trans-Isomerases / Q000378:metabolism; D000099178:Retinoid Isomerohydrolase
chemical_list: D017931:DNA Primers; D050612:Fatty Acid Transport Proteins; D005227:Fatty Acids; D012243:Rhodopsin; D019745:cis-trans-Isomerases; D000099178:Retinoid Isomerohydrolase; C493569:Slc27a1 protein, mouse; C493572:Slc27a4 protein, mouse