Assessment of DNA Damage in Leukocytes of Patients With Coronary Artery Disease by Comet Assay

Abstract

DNA damage in the peripheral blood leukocytes (PBL) of patients with coronary artery disease (CAD) was investigated using the sensitive alkaline single cell gel electrophoresis (SCGE)/comet assay.

This case-control study consisted of CAD patients (n = 200; mean age, 59.04 ± 0.75 years) undergoing treatment at local hospitals and age-, sex-, and ethnicity-matched healthy controls (n = 200; mean age, 57.88 ± 0.96 years) from the general population.

CAD patients had significantly (P < 0.001) increased DNA damage (tail DNA percent (T-DNA %) 22.45 ± 0.50 versus 5.81 ± 0.28; tail moment (TM) 89.35 ± 3.16 versus 9.98 ± 0.69; Olive tail moment (OTM) 60.50 ± 1.79 versus 10.94 ± 0.63; damage frequency (DF) 91.12 ± 0.93 versus 41.78 ± 2.04, damage index (DI) 173.68 ± 3.36 versus 48.53 ± 2.59) compared to controls. Patients with acute myocardial infarction (AMI) showed significantly higher DNA damage than patients with unstable angina (UA) (T-DNA % 24.05 ± 0.87 versus 21.06 ± 0.90; TM 100.02 ± 6.19 versus 81.61 ± 5.84; OTM 66.19 ± 3.20 versus 56.47 ± 3.33; DF 94.02 ± 0.84 versus 91.10 ± 1.16, DI 184.13 ± 5.33 versus 166.42 ± 5.89). Moreover, DNA damage was found to be significantly (P < 0.05) elevated in patients receiving ecosprin, ramipril, and metoprolol therapy compared to aspirin and nitrocontin.

The increased DNA damage in CAD patients may be the consequence of disease and/or drug therapy. These observations are of concern because unrepaired DNA can lead to malignancy, and the likelihood of increasing mortality and morbidity rates in CAD patients.