Abstract
Abstract: :
Purpose:Eales' disease (ED) is an idiopathic retinal vasculitis with retinal angiogenesis. Patients with ED have increased oxidant challenge and lowered antioxidant defense. Epiretinal membranes removed from these subjects are found to have abundant CML-AGE (a glycoxidative marker). In addition, these membranes contain infiltrating mononuclear cells. The present study was undertaken to understand the involvement of reactive nitrogen species (RNS) by using peripheral blood mononuclear cells (PBMNC). Methods:PBMNC from patients with ED (20-40 years) and control (age -sex matched) were used for our studies. These subjects are volunteers and informed participants in this research project. Expression studies on iNOS by Western blot, SOD activity by epinephrine autoxidation, estimation of TBARS by measuring MDA, analysis of trace elements by Atomic Absorption Spectrometer and determination of protein bound 3 Nitro tyrosine (3 NTYR) by RPHPLC, were performed in these cells. Results: Results are given in table 1. All values are meanSD. p<0.05 by students t test between test and control for all the parameters shown in the table 1. Conclusion:Increased levels of Fe and Cu can stimulate iNOS expression by generating OH·. Decreased activity of SOD may be attributed to low levels of Zn. Increased iNOS and diminished SOD can lead to protein nitrosylation via peroxynitrite (RNS) as evidenced by elevated levels of 3NTYR in ED. RNS along with ROS can damage membrane lipids to produce increased TBARS. This study and our earlier findings together emphasize an oxidative mechanism for ED. Further understanding on redox regulated transcription factors, may be necessary before introducing pharmacological interventions.
Table 1
Keywords: 491 nitric oxide • 504 oxidation/oxidative or free radical damage • 566 retinal neovascularization