Redox status in acute ischemic stroke: correlation with clinical outcome

Abstract

Connection between oxidative stress and clinical outcome in acute ischemic stroke (AIS) has been poorly investigated. This study was aimed to assess redox state (through measurement of oxidative stress markers) of patients with acute ischemic stroke during different stages of follow-up period, and to find association between values of mentioned markers and clinical outcome. The investigation was conducted on 60 patients (both sexes, aged 75.90 ± 7.37 years) who were recruited in intensive care units at the Special Hospital for Cerebrovascular Diseases "Sveti Sava," Belgrade. After verification of AIS, patients were followed up in four interval of time: (1) at admission, (2) within 24 h after AIS, (3) within 72 h after AIS, and (4) 7 days after AIS. At these points of time, blood samples were taken for determination of oxidative stress parameters [index of lipid peroxidation (measured as TBARS), nitric oxide (NO) in the form of nitrite ([Formula: see text]), superoxide anion radical ([Formula: see text]), hydrogen peroxide (H2O2)], and enzymes of antioxidant defense system [superoxide dismutase (SOD) and catalase (CAT)] using spectrophotometer. Present study provides new insights into redox homeostasis during ischemic stroke which may be of interest in elucidation of molecular mechanisms involved in this life-threatening condition. Particular contribution of obtained results could be examination of connection between redox disruption and clinical outcome in these patients. In that sense, our finding have pointed out that [Formula: see text] and NO can serve as the most relevant adjuvant biomarkers to monitor disease progression and evaluate therapies.

Can oxidative stress markers help define stroke prognosis?

“…These authors [10] were emphatic in stating that significantly higher levels of TBARS on the seventh day following stroke onset define (or could define) a poor prognosis. These results corroborate the findings of Paspalj et al [3] in the same interval of seven days after stroke onset, although this author did not ascertain any statistical significance. Moreover, they suggest that TBARS may not be sensitive enough to indicate prognosis and clinical monitoring.…”

“…Conversely, SOD can aid in the protection of antioxidant system components in the postischemic phase [11]. This biomarker presented a slight elevation in the blood levels of cadavers, but no statistical relevance was noted [3].…”

“…The available evidence indicates that there is a decrease in protein performance in cases where there are hemolytic alterations. Paspalj et al [3] point out that the levels of catalase demonstrated a slight increase in patients who did not survive, but no statistical relevance was verified. But for Žitnanova [5], there was a statistically significant increase in catalase levels, especially on the seventh day.…”

“…Moreover, they suggest that TBARS may not be sensitive enough to indicate prognosis and clinical monitoring. However, the effects of dynamic regulation of cerebrovascular blood circulation by NO, as well as antioxidant, anticoagulant and anti-inflammatory agents have led some authors [3] to infer the possibility of a better prognosis based on NO levels in comparison with TBARS-based prognoses. Furthermore, the study verified a relation between lethality and upward trends in the levels of this biomarker between the third and seventh days after stroke onset, albeit without statistical significance.…”

“…Ischemic stroke arises from an arterialobstructive blood clot in the brain, while hemorrhagic stroke is characterized by ruptured arteries resulting from vascular or hypertensive alterations. However, in the last few years, a number of studies have shown that redox balance is altered after stroke onset [2][3][4].…”