Deoxyribonucleic acid damage in human lymphocytes after percutaneous transluminal coronary angioplasty

OBJECTIVES; We investigated the presence of oxidative deoxyribonucleic acid (DNA) damage in the peripheral lymphocytes of patients undergoing percutaneous transluminal coronary angioplasty (PTCA) by using the micronucleus test and comet assay, which are sensitive biomarkers of DNA damage. BACKGROUND; Although it has recognized that ischemia-reperfusion can induce oxidative DNA damage, its occurrence in patients undergoing PTCA has not yet been demonstrated.

Three groups of patients were enrolled: 30 patients with documented coronary heart disease who underwent elective PTCA (group I); 25 patients who underwent elective coronary angiography for diagnostic purpose (group II); and 27 healthy, age- and gender-matched subjects (group III). For each subject, the frequency of micronucleated binucleated (MNBN) cells, DNA single-strand breaks (SSBs), endonuclease III-sensitive sites, and sites sensitive to formamidopyrimidine glycosylase (FPG) were analyzed before and after diagnostic procedures.

The mean basal values of MNBN cells (p = 0.04), DNA-SSBs (p = 0.001), endonuclease III-sensitive sites (p = 0.002), and FPG sites (p < 0.0001) were significantly higher in groups I and II than in group III. A high significant increase of MNBN cell frequency was observed in group I after the PTCA procedure (11.0 +/- 1.3 vs. 19.8 +/- 1.6, p < 0.0001), whereas no significant difference was observed in group II (10.2 +/- 1.3 vs. 12.9 +/- 1.4, p = 0.18). A significant positive correlation was observed between the increase in the MNBN cell rate and total inflation time during PTCA (R = 0.549, p = 0.0017). The levels of DNA-SSBs (11.7 +/- 1.4 vs. 26.5 +/- 3.0, p = 0.0003) and FPG sites (13.8 +/- 1.8 vs. 22.5 +/- 2.4, p = 0.01) were also higher after PTCA.

Our results provide evidence for oxidative DNA damage after PTCA, likely related to ischemia-reperfusion injury.