Metabolic rescue of retinal degeneration

A method of diagnosing and treating a subject with retinitis pigmentosa, the method comprising:

• a) obtaining a vitreous sample from the subject;
• b) measuring one or more biomarkers in the vitreous sample, wherein the biomarkers are selected from the group consisting of rhodopsin, guanine nucleotide-binding protein alpha subunit and beta subunit, phosducin, cyclic nucleotide-gated channel beta 1, rhodopsin kinase, recoverin, and S-arrestin;
• c) determining that the subject has increased levels of the one or more biomarkers selected from the group consisting of rhodopsin, guanine nucleotide-binding protein alpha subunit and beta subunit, phosducin, cyclic nucleotide-gated channel beta 1, rhodopsin kinase, recoverin, and S-arrestin in the vitreous sample compared to reference values ranges for levels of the one or more biomarkers in a control sample, wherein the increased levels of the one or more biomarkers indicate the subject has retinitis pigmentosa;
• and
• d) administering to the subject diagnosed with retinitis pigmentosa a therapeutically effective amount of α-ketoglutarate or a derivative thereof.