title: Taurine deficiency damages retinal neurones: cone photoreceptors and retinal ganglion cells.
abstract: In 1970s, taurine deficiency was reported to induce photoreceptor degeneration in cats and rats. Recently, we found that taurine deficiency contributes to the retinal toxicity of vigabatrin, an antiepileptic drug. However, in this toxicity, retinal ganglion cells were degenerating in parallel to cone photoreceptors. The aim of this study was to re-assess a classic mouse model of taurine deficiency following a treatment with guanidoethane sulfonate (GES), a taurine transporter inhibitor to determine whether retinal ganglion cells are also affected. GES treatment induced a significant reduction in the taurine plasma levels and a lower weight increase. At the functional level, photopic electroretinograms were reduced indicating a dysfunction in the cone pathway. A change in the autofluorescence appearance of the eye fundus was explained on histological sections by an increased autofluorescence of the retinal pigment epithelium. Although the general morphology of the retina was not affected, cell damages were indicated by the general increase in glial fibrillary acidic protein expression. When cell quantification was achieved on retinal sections, the number of outer/inner segments of cone photoreceptors was reduced (20 %) as the number of retinal ganglion cells (19 %). An abnormal synaptic plasticity of rod bipolar cell dendrites was also observed in GES-treated mice. These results indicate that taurine deficiency can not only lead to photoreceptor degeneration but also to retinal ganglion cell loss. Cone photoreceptors and retinal ganglion cells appear as the most sensitive cells to taurine deficiency. These results may explain the recent therapeutic interest of taurine in retinal degenerative pathologies.
authors.affiliation: INSERM, U-968, Insitut de la Vision Retinal Information Processing: Pharmacology and Pathologies, 17, rue Moreau, 75012 Paris, France.
authors.forename: David
authors.initials: D
authors.lastname: Gaucher
authors.forename: Emilie
authors.initials: E
authors.lastname: Arnault
authors.forename: Zoé
authors.initials: Z
authors.lastname: Husson
authors.forename: Nicolas
authors.initials: N
authors.lastname: Froger
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Dubus
authors.forename: Pauline
authors.initials: P
authors.lastname: Gondouin
authors.forename: Diane
authors.initials: D
authors.lastname: Dherbécourt
authors.forename: Julie
authors.initials: J
authors.lastname: Degardin
authors.forename: Manuel
authors.initials: M
authors.lastname: Simonutti
authors.forename: Stéphane
authors.initials: S
authors.lastname: Fouquet
authors.forename: M A
authors.initials: MA
authors.lastname: Benahmed
authors.forename: K
authors.initials: K
authors.lastname: Elbayed
authors.forename: Izzie-Jacques
authors.initials: IJ
authors.lastname: Namer
authors.forename: Pascale
authors.initials: P
authors.lastname: Massin
authors.forename: José-Alain
authors.initials: JA
authors.lastname: Sahel
authors.forename: Serge
authors.initials: S
authors.lastname: Picaud
mesh_terms: D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D004195:Disease Models, Animal; D004596:Electroretinography; D005136:Eye Proteins / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects; D005904:Glial Fibrillary Acidic Protein / Q000235:genetics* / Q000378:metabolism; D006146:Guanidines / Q000494:pharmacology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009473:Neuronal Plasticity / Q000187:drug effects; D017949:Retinal Cone Photoreceptor Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D012162:Retinal Degeneration / Q000139:chemically induced / Q000378:metabolism / Q000473:pathology*; D012165:Retinal Ganglion Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D055213:Retinal Pigment Epithelium / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D013654:Taurine / Q000037:antagonists & inhibitors / Q000172:deficiency*
chemical_list: D005136:Eye Proteins; D005904:Glial Fibrillary Acidic Protein; D006146:Guanidines; D013654:Taurine