Antioxidant status in acute stroke patients and patients at stroke risk

Background and Purpose: Antioxidant enzymes like copper/ zinc
superoxide dismutase (SOD), catalase and gluthatione peroxidase
(GSHPx) are part of intracellular protection mechanisms to overcome
oxidative stress and are known to be activated in vascular diseases
and acute stroke. We investigated the differences of antioxidant
capacity in acute stroke and stroke risk patients to elucidate
whether the differences are a result of chronic low availability in
arteriosclerosis and stroke risk or due to changes during acute
infarction. Methods: Antioxidant enzymes were examined in 11
patients within the first hours and days after acute ischemic
stroke and compared to risk- and age-matched patients with a
history of stroke in the past 12 months ( n = 17). Antioxidant
profile was determined by measurement of glutathione (GSH),
malondialdehyde (MDA), SOD, GSHPx and minerals known to be involved
in antioxidant enzyme activation like selenium, iron, copper and
zinc. Results: In comparison to stroke risk patients, patients with
acute ischemic stroke had significant changes of the GSH system
during the first hours and days after the event: GSH was
significantly elevated in the first hours (p < 0.01) and GSHPx
was elevated 1 day after the acute stroke (p < 0.05). Selenium,
a cofactor of GSHPx, was decreased (p < 0.01). GSHPx levels were
negatively correlated with National Institutes of Health Stroke
Scale (NIHSS) scores on admission (r = - 0.84, p < 0.001) and
NIHSS scores after 7 days ( r = - 0.63, p < 0.05). MDA levels
showed a trend for elevation in the first 6 h after the acute
stroke ( p = 0.07). No significant differences of SOD, iron, copper
nor zinc levels could be identified. Conclusions: Differences of
antioxidant capacity were found for the GSH system with elevation
of GSH and GSHPx after acute stroke, but not for other markers. The
findings support the hypothesis that changes of antioxidant
capacity are part of acute adaptive mechanisms during acute stroke.
Copyright (C) 2004 S. Karger AG, Basel.