Nutraceutical supplementation in inherited retinal dystrophies

Abstract

*Correspondence: rrodrigo@cipf.es; Tel: (+34 96 328 96 80)Retinitis pigmentosa (RP) is the most common inherited retinal dystrophy causing progressive vision loss. Ocular redox status is altered in RP suggesting oxidative stress could contribute to their progression. In addition, it is accompanied by chronic and sustained inflammation, including M1 microglia activation. In our group we evaluated, both the effect of a mixture of nutraceuticals with antioxidant properties (NUT) and the effect of an essential fatty acid (EFA) supplement containing specialized pro‐resolving mediators (SPMs) on retinal degeneration in rd10 mice, a model of RP.Both compounds were orally administered to mice from postnatal day (P)9 to P18. At P18, the electrical activity of the retina was examined by electroretinography (ERG) and innate behaviour in response to light were measured. Retinal degeneration was studied via histology including the TUNEL assay and microglia immunolabelling. Microglia polarization (M1/M2) was assessed by flow cytometry, qPCR and histology. Redox status was analysed by measuring antioxidant enzymes and markers of oxidative damage.Interestingly, the NUT and EFA supplements ameliorated retinal dysfunction and degeneration by improving ERG recording and sensitivity to light, and reducing photoreceptor cell loss.The supplement reduced inflammation and microglia activation attenuating M1 markers as well as inducing a shift to the M2 phenotype in rd10 mouse retinas. These supplements also reduced oxidative stress markers of lipid peroxidation and carbonylation. These findings could open up new therapeutic opportunities with oral supplementation.