Tobacco consumption and benzo(a)pyrene-diol-epoxide-DNA adducts in spermatozoa: in smokers, swim-up procedure selects spermatozoa with decreased DNA damage

Abstract

Objective: To analyze the distribution of benzo(a)pyrene-diol-epoxide (BPDE)-DNA adducts in spermatozoa selected and nonselected by a swim-up procedure with relation to smoking habits.

Design: Comparative study.

Setting: Public university and public university hospital.

Patient(s): Seventy-nine men (37 smokers and 42 nonsmokers) who visited an infertility clinic for diagnostic.

Intervention(s): Tobacco and environmental exposure assessment, semen sample analysis, swim-up procedure, BPDE-DNA adduct immunolabeling.

Main outcome measure(s): BPDE-DNA adduct quantification in selected (SEL-SPZ) and nonselected (NONSEL-SPZ) spermatozoa. Data were normalized by using a normalized fluorescence value (NFV).

Result(s): The mean NFV (±SD) in SEL-SPZ was significantly higher in smokers than in nonsmokers (18.9±11.5 vs. 10.5±10.4, respectively). Within smokers, a paired analysis (SEL-SPZ and NONSEL-SPZ) showed that NFV was significantly lower in SEL-SPZ than in NONSEL-SPZ (20.0±11.3 vs. 31.5±16.0, respectively). Conversely, within nonsmokers, the mean NFV was higher in SEL-SPZ than in NONSEL-SPZ (10.3±10.6 vs 4.3±7.1, respectively).

Conclusion(s): Tobacco consumption is associated with BPDE-DNA adducts in spermatozoa. In smokers, semen processing by swim-up recovers potentially fertilizing spermatozoa that show a significantly lower amount of BPDE-DNA adducts compared with NONSEL-SPZ. Further study is needed to improve the spermatozoa selection in smoking patients requiring assisted reproductive technologies.