Investigation of oxidative DNA damage from tourniquet-induced ischemia-reperfusion injury in orthopedic patients.

Free oxygen radicals and lipid peroxidation play an important role in a number of biological processes. Reactive oxygen species (ROS) produced either endogenously or exogenously cause oxidative DNA damage. Oxidative DNA damage in cells was caused by endogenously and exogenously reactive oxygen species (ROS), involving free radicalsThirty-three orthopedic patients (age; 41.48±13.83) who applied to Gazi University Faculty of Medicine, Orthopedic and Traumatology Department for meniscopathy surgery were includedPeripheral blood lymphocytes were collected in heparinized glass tubes at the following stages of the intervention: the reference level was obtained immediately before operation. The second sample was taken after tourniquet (ischemia) and third sample was taken after the release of tourniquet (reperfusion). Oxidative DNA damage in peripheral lymphocytes was evaluated by comet assay using spesific enzymes (Endo III and FPG). We could not find statistically significant difference was not observed when all stages were compared to each other for tail intensity (7.71±2.042; 8.11±2.131 and 8.27±1.57 for basal DNA, p>0.05). We also obtained similar results when it was used Endo III and FPG (8.66±2.575; 8.5±1.99 and 8.98±2.19 for pyrimidine damage, 8.41±2.948; 9.06±2.61 and 9.29±3.54 for purine damage, respectively). Furthermore, we compared to smoker patients to non-smoker patients to detect the effect of smoking status on DNA damage. There was no statistically significant increase in smoker patients compared to non-smokers (p>0.05). When it was analyzed the effects of age and gender on DNA damage, there were no correlation observed. (r² = 0.054, r = -232, p=0.20. Spearman Correlation testOur data showed that tourniquet-induced ischemia-reperfusion injury in orthopedic patients did not cause oxidative DNA damage. It needs to be done further studies to detect mechanism of ischemia-reperfusion induced DNAKey Words : Comet assay . Tourniquet . Ischemia-Reperfusion