Biology and Medicine

Abstract

Free-Radical Processes in Stroke Patients with Vascular Comorbidity

Ekaterina Vladimirovna Silina, Aleksandra Sergeevna Orlova, Sofia Alekseevna Rumyantseva and Sergej Brankovich Bolevich

Acute oxygen and glucose defi ciency during brain ischemia leads to the inability of neurons producing a suffi cient amount of adenosine triphosphate (ATP) using an oxidative metabolism. Energy defi ciency leads to neuronal death via different mechanisms including oxidative stress. This study aimed to evaluate the changes and main characteristics of free-radical processes in patients with acute stroke and transient ischemic attacks (TIA) in the presence of vascular comorbidity. One hundred forty-one patients with stroke (male—72, mean age—65.4813.44 years) and with a history of cardiovascular diseases (CVD). Free-radical formation was assessed in plasma based on oxidative (chemiluminescence intensity index—basal [CIIb] and zymosan-stimulated [CIIs]) and lipid-peroxidation markers (antiperoxide plasma activity [APA] and malondialdehyde [MDA]). During the follow-up period (from 6 to 72 months) the incidence of recurrent cardiovascular events, outcomes, and survival were assessed using a telephone interview. All patients who survived were rehospitalized and underwent neurologic assessment. A high level of vascular comorbidity was demonstrated. The level of imbalance of free-radical processes correlated with an acute-stroke severity with a maximal intensity of lipid peroxidation in hemorrhagic stroke and the activation of oxidative stage of free-radical processes in ischemic stroke. There was a signifi cant decrease of APA in both types of stroke, whereas TIA was characterized by maintenance of high APA levels (p  0.05). In patients with an acute-stroke free-radical imbalance increased proportional to the level of a vascular comorbidity. The decrease of APA level and increase of MDA level, which refl ect signifi cant oxidative imbalance and more extensive vascular damage, correlate with inferior recovery during the inpatient period (r 5 0.357; p  0.05 и r 5 0.234; p  0.001 respectively). It was demonstrated that low MDA and high APA level in patients with acute stroke are the prognostic markers of a good functional recovery during inpatient treatment and decreased strokeassociated mortality during long-term follow-up.