Erythrocyte oxidative stress is associated with cell deformability in patients with retinal vein occlusion

SummaryBackground Retinal vein occlusion (RVO) is characterized by vision loss due to hypoperfusion and hypoxia of the retina. RVO pathogenesis is not yet fully understood, although blood hyperviscosity has been observed. Erythrocyte deformability plays a key role in determining blood viscosity, and it is critical to microvascular perfusion and oxygen delivery. It has been shown that oxidative stress-induced erythrocyte membrane fluidity alterations are linked to the progression of cardiovascular diseases. Objectives The objective of the present study is to find out if erythrocytes from RVO patients show signs of oxidative stress and if this condition can modify the haemorheological profile in these patients. Patients and Methods We analyzed whole haemorheological profile and erythrocyte oxidative stress - Reactive Oxygen Species (ROS) production and membrane lipid peroxidation – in 128 RVO patients and 128 healthy subjects, matched for age and sex. Fluorescence anisotropy was used to evaluate the fluidity of erythrocyte membranes. Results In RVO patients, erythrocyte oxidative stress was present and positively correlated to whole blood viscosity and erythrocyte deformability. Multivariate linear regression analysis after adjusting for age, cardiovascular risk factors, medications, leukocyte number and mean corpuscolar volume (MCV), indicated that erythrocyte-derived ROS and erythrocyte lipid peroxidation were significantly and positively correlated with erythrocyte membrane viscosity and deformability. Moreover, in vitro experiments demonstrated that ROS display a key role in erythrocyte membrane fluidity. Conclusions Our findings indicate that erythrocyte oxidative stress plays a key role in the pathogenesis of RVO, and pave the way to new therapeutic interventions. This article is protected by copyright. All rights reserved.