Aims: 

Free radicals play an important role in the pathogenesis of brain injury. The purpose of this study was to evaluate the potential relationship between the peripheral oxidative stress and ischaemia/reperfusion (I/R)-induced brain.

Methods: 

We quantified: (1) lymphocyte DNA damage, (2) plasma antioxidant potential and (3) uric acid levels as well as (4) a time course of peripheral oxidative stress on reperfusion period after ischaemic attack.

Results: 

We observed that 15 min of ischaemia significantly increased lymphocyte DNA damage. In parallel, antioxidant potential was significantly elevated after 15 min of ischaemia, as well as after 3 h of reperfusion, when compared to pre-operative levels. A significant correlation can be found between the plasma uric acid and antioxidant potential of plasma after brain I/R. Evidence is presented by in vitro experiments that uric acid is the main component of increased antioxidant capacity seen in early reperfusion period. A significant decrease in total antioxidant potential was observed at 72 h reperfusion and this fall is correlated with the decrease of uric acid level.

Conclusions: 

These results indicate a close time dependent association between brain I/R-associated oxidative stress and peripheral antioxidant defence status and/or oxidative stress in animal experiments. The study also suggests for uric acid and antioxidant capacity as an independent clinical outcome predictors in stroke patients.

Supported by: VEGA 3380/06, MVTS COST B30.