Fig. 3: Gene therapy delivery of human NMNAT2 is strongly neuroprotective to retinal ganglion cells.
From: NMNAT2 is a druggable target to drive neuronal NAD production
A Overexpression of hNMNAT2 robustly protects against RGC loss in Nmnat2gtBay/gtE (25%) retinas maintained for 3 days ex vivo following axotomy, rescuing the RGC sensitization phenotype of these mice (Day 0: Nmnat2gtBay/gtE, n = 6; Day 3: Nmnat2gtBay/gtE, n = 6; Nmnat2gtBay/gtE + hNMNAT2, n = 5; scale bar = 20 µm). B Overexpression of hNMNAT2 in C57BL/6J mice confers complete protection against RGC loss at 3 days ex vivo (n = 6 retinas for all conditions). C In the rat ocular hypertension (OHT) model, which recapitulates many features of human glaucoma, significant RGC loss occurs following 14 days of elevated intraocular pressure (OHT) relative to controls (NT, normotensive). Transfection (3 weeks prior to OHT onset) and expression of GFP alone (AAV GFP) does not significantly alter RGC survival, but RGC survival is significantly enhanced with hNMNAT2 expression. This demonstrates that in a complex disease (with many neurodegenerative mechanisms) NMNAT2 gene therapy provides moderate neuroprotection to RGCs (NT n = 12 eyes, OHT n = 9 eyes, OHT AAV GFP n = 10 eyes, OHT hNMNAT2 n = 8 eyes). Scale bars = 25 µm in all images. For A, B and C, *P < 0.05, **P < 0.01, ***P < 0.001, NS non-significant (P > 0.05); One-way ANOVA with Tukey’s HSD. For box plots, the centre hinge represents the median with upper and lower hinges representing the first and third quartiles; whiskers represent 1.5 times the interquartile range.
