Abstract
Purpose: :
to investigate the expression of glutamine synthase (GS), nitric oxide synthase (NOS) superoxide dismutase (SOD) and glutathione transferase (GST) in the acqueous humor of patients with primary open angle glaucoma (POAG) and controls.
Methods: :
acqueous humor proteome was analysed by antibody microarray. The expression of tested proteins was detected by protein Cy3/Cy5 labelling, column purification and hybridisation on antibody-spotted glass microarray. Fluorescent signals were detected by fluorescence laser scanning.
Results: :
acqueous humor levels of SOD as well as of GST were significantly lower (p < 0.01) among POAG patients than controls; both NOS and GS expression were significantly higher (p<0.01) among POAG patients than controls.
Conclusions: :
our data support the hypothesis that a progressive accumulation of oxidative damage in the anterior chamber of the eye and specifically at the trabecular meshwork (TM) level occurs during POAG. The overproduction of NO through inducible NOS may lead to toxic products generation by interacting with oxygen, iron, and/or copper thus changing the metabolic conditions of the TM and altering its mobility. Since the TM has a neuronal embryogenic derivation, the GS over-expression might be related to neuronal injury as well as TM damage and malfunctioning. The reduced expression of the antioxidant enzymes SOD and GST could aggravate the unbalance between both oxygen (ROS) and nitrogen (RNS) derived free radicals production and detoxification.
Keywords: oxidation/oxidative or free radical damage • aqueous • trabecular meshwork