Abstract
Purpose: :
Several genes involved in complement cascade, extra cellular matrix modeling, oxidative stress and cholesterol metabolism pathways have been implicated in age-related macular degeneration (AMD) The present study aimed to evaluate the expression of these genes in plasma samples in order to understand their potential role in AMD pathogenesis.
Methods: :
Plasma (3ml) were collected from patients with different stages of AMD (n=60) and age adjusted cataract controls (n=60) having no systemic history of diabetes, hypertension and any long illness with prior written informed consent, aliquoted and stored at -80°C. The concentrations of 28 proteins involved in neuro-degeneration, extracellular matrix modelling, angiogenesis and inflammatory pathways; α2-Macroglobulin, Apolipoprotein A1, Apolipoprotein C3, Apolipoprotein E, Complement Components, Prealbumin, Matrix metalloproteases and Tissue Inhibitor of Metalloproteases (TIMPs) etc. were evaluated in pre-diluted plasma samples using multiplex bead immunoassays (Luminex xMAP technology). Differences between levels of these proteins were analyzed using appropriate statistical tests.
Results: :
25 of the 28 analytes were detectable in the plasma samples. Patients with AMD exhibited significant elevations in C3 (p=0.0001), while CFH was relatively higher in the controls (p=0.023). Among the ECM-related proteins, TIMP1 exhibited a higher concentration in AMD (p=0.023). The other proteins did not exhibit significant differences in the plasma of patients and controls (p>0.05).
Conclusions: :
Significant alterations in complement and ECM components in AMD patients further corroborates contributions of the gene involved in the abnormal complement cascade and ECM modeling identified through genomic associations in the AMD pathogenesis.
Keywords: age-related macular degeneration • proteins encoded by disease genes • genetics