Stroke is a serious health problem all over the world and the second, after the heart attack, cause of death and permanent disability in people. Oxidative stress plays an important role in the pathogenesis of ischemic stroke (AIS).

The aim of our study was to evaluate the temporal profile of the melatonin metabolite 6-hydroxymelatonin sulphate (6-SM) in the urine and carbonyl groups in the serum of patients with acute ischemic stroke treated with intravenous thrombolysis.

There were statistically significant differences between the values of 6-SM and carbonyls compared to the control group. Statistical differences were also found in the concentrations of the examined parameters depending on the type of stroke. The studies revealed the correlations between the concentrations of 6-SM and the carbonyl groups measured in various time intervals and between the concentration of biomarkers and mortality was also evaluated.

The obtained results may indicate an increased oxidative stress, and the intense increase in the concentration of carbonyl groups in patients with AIS may be considered a potential marker of protein damage in thrombolytic patients. Melatonin supplementation in AIS patients can also be considered, as it can effectively prevent both behavioral and neurophysiological defects caused by cerebral hypoxia and ischemia.