Abstract
Purpose: :
Diabetic retinopathy is characterized by inflammation, vascular lesions, and neuronal death and dysfunction. We have previously demonstrated duration-dependent permeability, apoptosis, and genomic retinal changes with diabetes. The aim of this study was to identify proteomic alterations associated with functional deregulation of the retina with diabetes.
Methods: :
Proteomic analysis has improved recently but no single proteomic method can examine the entire proteome. To provide the most comprehensive proteomic analysis possible multiple proteomic methods were used. Open screen methods of iTRAQ and 2DIGE as well as focused analysis (Luminex) were performed on whole retinal lysates from Sprague Dawley rats three months post-STZ induction of diabetes.
Results: :
Proteomic analysis of retinal protein identified changes associated with metabolism, cellular morphology, inflammation, and neuronal function. Specific proteins deregulated included cytoskeletal elements (Cryaa, Drp2), metabolic enzymes (Nme1, Pdh), cytokines (e.g. Fgf, IL14), and other proteins (PAF1B). Some protein expression differences were found by multiple proteomic methods while others were identified only by a single method. The coverage of the different proteomic methods was similar in that some proteins appeared across methods while others were specific to a single technical approach.
Conclusions: :
Technically, these results demonstrate the utility of a multimodal analysis for proteomic research. The use of multiple technical approaches provided a broader analysis of the retinal proteome than one single method. The protein expression changes identified add further evidence that diabetes causes changes across multiple physiological processes including microvascular, inflammatory, and neuronal processes.
Keywords: diabetes • proteomics • retina