The treatment of cyanine dye NK-4 against photoreceptor cell apoptosis in a rat model of Retinitis Pigmentosa

NK-4 is a divalent cationic pentamethine trinuclear cyanine dye, and it has been studied over 150 years. The injection of NK-4 effectively attenuated the apoptosis of photoreceptor cells, increased the thickness of the outer nuclear layer, and exerted neuroprotective role against retinal apoptosis by promoting anti-apoptotic and anti-oxidative pathways. These findings provide new insight into molecular mechanismsby which NK-4 exhibits neuroprotective effects in RCS rats, and suggest that NK-4 might become a new neuroprotective agent for the prevention and treatment of retinal degeneration.