Biomarkers useful in the treatment of subjects having diseases of the eye
The present invention provides biomarkers of oxidative stress in subjects with retinitis pigmentosa, age-related macular degeneration, diabetic retinopathy, Fuchs' dystrophy, diabetic macular edema (DME), geographic atrophy, Stargardt's disease, or retinal vein occlusion (RVO), and their use in identifying subjects in need of treatment and methods for staging the severity of the disease.
1. A method for determining and treating oxidative stress in the eye comprising:
a) obtaining a sample from a subject;
b) providing a control sample;
c) measuring one or more of the following: cupric reducing antioxidant capacity, GSH/GSSG ratio, and carbonyl adduct level in the sample of a) and b);
d) comparing the one or more measurements of c) in the sample from the subject to the control serum sample;
e) quantifying the oxidative stress in the eye, if the levels of cupric reducing antioxidant capacity and/or GSH/GSSG ratio is reduced relative to the control serum sample, and/or if the levels of carbonyl adduct level is elevated relative to the control serum sample, wherein the levels of protein carbonyl levels are determined by EIA (enzyme immunoassay), ELISA (enzyme linked immunosorbent assay), RIA (radioimmunoassay), indirect competitive immunoassay, direct competitive immunoassay, non-competitive immunoassay, sandwich immunoassay, agglutination assay, Western blot assay, slot blot assay, fluorescence polarization, latex agglutination, lateral flow assay, immunochromatographic assay, immunochips, dip stick immunotesting, or bead-based technology; and
f) administering an effective treatment to the subject having oxidative stress in the eye, wherein the effective treatment comprises N-Acetylcysteine Amide (NACA).
2. The method of claim 1 , wherein the sample is from the aqueous humor of the eye of the subject.
3. The method of claim 1 , wherein the sample is from the blood or plasma of the subject.
4. A method for quantifying and treating oxidative stress in an eye of a subject comprising:
a. obtaining a biological sample from the eye of the subject;
b. providing a control biological sample;
c. ratio, and carbonyl adduct level in the sample of a) and b); and
d. comparing the one or more measurements of c) in the sample from the subject to the control sample, wherein an increase in carbonyl adduct level, a ratio of GSH to GSSG is reduced, and/or a reduction in cupric antioxidant capacity is indicative of oxidative stress, wherein the levels of protein carbonyl levels are determined by EIA (enzyme immunoassay), ELISA (enzyme linked immunosorbent assay), RIA (radioimmunoassay), indirect competitive immunoassay, direct competitive immunoassay, non-competitive immunoassay, sandwich immunoassay, agglutination assay, Western blot assay, slot blot assay, fluorescence polarization, latex agglutination, lateral flow assay, immunochromatographic assay, immunochips, dip stick immunotesting, or bead-based technology; and
e. administering an effective treatment to the subject having oxidative stress in the eye, wherein the effective treatment comprises N-Acetylcysteine Amide (NACA).
5. The method of claim 4 , wherein the sample is from the aqueous humor of the eye of the subject.
6. The method of claim 4 , further comprising the step of measuring cone cell death upon a finding of an increase in carbonyl adduct level, a ratio of GSH to GSSG is reduced, and/or a reduction in cupric antioxidant capacity is indicative of oxidative stress in the subject.