HDAC9 and retinal degeneration: As mentioned previously, class I/II HDAC inhibitors (HDACi) demonstrate neuroprotective and restorative effects on retinal morphology in mouse models of retinal degeneration.20, 58 While isoform selectivity of HDACi is a contentious issue, trichostatin A and scriptaid, two pan- or class I/II selective HDACi have potent inhibitory activity against HDAC6.59 Thus, HDAC6 inhibition may have a significant role in the neuroprotective effects of these less selective HDACi.