Impact of PTEN/SOCS3 deletion on amelioration of dendritic shrinkage of retinal ganglion cells after optic nerve injury.

This study investigated the effect of PTEN/SOCS3 genetic deletion on the structural integrity of RGC dendrites and axons in the retina following optic nerve crush. Using time lapse, in vivo confocal scanning laser ophthalmoscopy to serially image dendritic and axonal arborizations of RGCs over six months after injury, RGC dendrites and axons were only preserved in Thy-1-YFP/PTEN-/- and Thy-1-YFP/PTEN-/-SOCS3-/- mice, and axons in the retina regenerated at a rate of 21.1  μm/day and 15.5  μm/day, respectively. By contrast, dendritic complexity significantly decreased in Thy-1-YFP-SOCS3-/- and control mice at a rate of 7.0%/day and 7.1%/day, respectively, and no axon regeneration in the retina was observed. RGC survival probability was higher in Thy-1-YFP/PTEN-/- and Thy-1-YFP/PTEN-/-SOCS3-/- mice compared with Thy-1-YFP-SOCS3-/- and control mice. The differential responses between the transgenic mice demonstrate that although a genetic deletion of PTEN, SOCS3, or PTEN/SOCS3 is sufficient for RGC axon regeneration in the optic nerve, a deletion of PTEN, but not SOCS3, ameliorates RGC dendritic shrinkage after optic nerve crush. This shows that the signaling pathways involved in promoting axon regeneration do not equally contribute to the preservation of dendrites, which is crucial to the translational application of neuroregenerative therapeutic alternatives for visual restoration.
PMID: 31972211 [PubMed - as supplied by publisher]

Source: Experimental Eye Research - January 19, 2020 Category: Opthalmology Authors: Mak HK, Ng SH, Ren T, Ye C, Leung CKS Tags: Exp Eye Res Source Type: research