NGF and Retinitis Pigmentosa: Structural and Molecular Studies

Nerve growth factor (NGF) is a neuroprotective molecule performing not only on central and peripheral neurons but also on cells of the visual system. Human retinitis pigmentosa (RP) is a major cause of blindness worldwide, and a resolute therapy is still lacking. Recent studies have shown that ocular NGF administration exerts a protective action on damaged retinal cells of mammalians, including human beings, although whether NGF also protects photoreceptors is not clear.We used the Royal College of Surgeons (RCS) strain in this study. The RCS is a rodent affected by inherited retinitis pigmentosa (RP) during postnatal life. For this study, we investigated whether ocular NGF treatment reduces/stops the progression of photoreceptor degeneration of rats with RP.This study was carried out in vitro on isolated photoreceptors to further investigate the action on these cells and whether the action is direct or mediated.The results indicate that ocular NGF administration can protect photoreceptors from degeneration into a model developing inherited RP and that the NGF action is direct. In this regard, we observed that binding of NGF to its receptor modulates expression of rhodopsin, a specific biological marker for photoreceptor survival and functionality.Part of the data reported in this chapter has been published in a previous study.