N-acetyl cysteine reduces chromosomal DNA damage in circulating lymphocytes during cardiac catheterization procedures: A pilot study

Abstract

BackgroundN-acetylcysteine (NAC) is considered a promising radio-protector for its antioxidant and anticarcinogenic properties. We examined the ability of NAC to confer protection against radiation-induced chromosomal DNA damage during cardiac catheterization procedures. MethodsSixty-five patients (52 males, age 64.4±11.9years) undergoing invasive cardiovascular procedures (peripheral transluminal angioplasty, n=45; cardiac resynchronization therapy, n=15 and ablation therapy n=5) were enrolled: 35 patients (26 males, age 63.4±11.1years) received the standard hydration protocol consisting of intravenous isotonic saline for 12h after catheterization (Group I), and 30 patients (26 males, age 65.5±12.9years) received a clinically driven double intravenous dose of NAC (6mg/kg/h diluted in 250mL of NaCl 0.9%) for 1h before and a standard dose (6mg/kg/h diluted in 500mL of NaCl 0.9%) for 12h following catheterization (Group II). Micronucleus assay (MN) was performed as biomarker of chromosomal DNA damage before, 2 and 24h after the radiation exposure. Dose-area product (DAP; Gy cm2) was assessed as physical measure of radiation load. ResultsDAP was higher in NAC-treated patients (I=54.7±23.6 vs II=126.2±79.2Gy cm2, p=0.0001). MN frequency was 13.7±4.7‰ at baseline and showed a significant rise at 2h (18.0±6.8 p=0.01) and 24h (17.6±5.9, p=0.03) in the Group I. There was no significant increase of MN in the Group II (13.7±7.0, 15.5±6.0 and 14.9±6.3 for baseline, 2h and 24h respectively, p=0.4). ConclusionNAC treatment given to prevent contrast-induced nephropathy may also reduce DNA damage induced by ionizing radiation exposure during cardiac catheterization procedures.